Exhibit 10.24  Execution Copy  COLLABORATIVE DEVELOPMENT,  COMMERCIALIZATION AND LICENSE AGREEMENT  BY AND BETWEEN  SYNTA PHARMACEUTICALS CORP.  and  SMITHKLINE BEECHAM CORPORATION  (d/b/a GLAXOSMITHKLINE)  October 8, 2007        Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.


TABLE OF CONTENTS  Page1.
  DEFINITIONS
  12.
  ADMINISTRATION
  OF THE COLLABORATION
  212.1
  Joint Steering Committee
  212.2
  Joint Development
  Committee
  242.3
  Joint Commercialization
  Committee
  272.4
  Alliance Managers
  302.5
  Joint Patent Committee
  302.6
  Interests of the Parties,
  Limitations of Powers
  322.7
  Appointment Not an
  Obligation; No Breach
  323.
  DEVELOPMENT
  OF PRODUCTS
  323.1
  Implementation of
  Development Program
  323.2
  Development Diligence and
  Compliance
  363.3
  Development Program
  Reports
  373.4
  Right of Access;
  Cooperation
  373.5
  Supply of Proprietary
  Materials; Technology Transfer
  373.6
  Development Cost-Sharing;
  Reconciliation
  374.
  REGULATORY
  394.1
  Responsibility for
  Regulatory Filings
  394.2
  Review and Preparation of
  Regulatory Filings; Regulatory Meetings Prior to Completion of Regulatory
  Filings Transfer Plan
  414.3
  Review and Preparation of
  Regulatory Filings; Regulatory Meetings After Completion of Regulatory
  Filings Transfer Plan
  405.
  COMMERCIALIZATION
  OF PRODUCT
  415.1
  Responsibility for
  Commercialization of Products
  415.2
  Exercise of
  Commercialization Opt-Out Right
  435.3
  Commercialization Plans
  435.4
  Commercialization
  Diligence and Compliance
  445.5
  Cooperation
  445.6
  Commercialization Reports
  445.7
  Pharmacovigilance; Adverse
  Event Reports
  455.8
  Labeling
  456.
  PAYMENTS
  456.1
  Up-front Fee
  456.2
  Equity Purchases.
  456.3
  Operating Income Payments
  476.4
  Milestone Payments.
  47   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.  i


6.5
  Payment of Royalties;
  Royalty Rates; Accounting and Records
  496.6
  Payment Dates and Reports
  566.7
  Records; Audit Rights
  546.8
  Overdue Payments
  546.9
  Payments; Withholding Tax
  556.10
  Foreign Currency Exchange
  556.11
  Invoices
  567.
  TREATMENT
  OF CONFIDENTIAL INFORMATION; PUBLICITY
  567.1
  Confidentiality
  567.2
  Publicity
  577.3
  Publications and
  Presentations
  577.4
  Permitted Publications
  588.
  LICENSE
  GRANTS; EXCLUSIVITY; STANDSTILL AGREEMENT
  588.1
  License
  588.2
  Right to Sublicense
  598.3
  No Other Rights
  608.4
  Exclusivity
  608.5
  Standstill Agreement
  619.
  
  INTELLECTUAL
  PROPERTY RIGHTS
  629.1
  SYNTA Intellectual
  Property Rights
  629.2
  GSK Intellectual Property
  Rights
  629.3
  Joint Technology Rights
  629.4
  Inventorship
  6310.
  FILING,
  PROSECUTION AND MAINTENANCE OF PATENT RIGHTS
  6310.1
  Patent Filing, Prosecution
  and Maintenance.
  6310.2
  Legal Actions.
  6410.3
  Trademarks, Logos, Etc
  6711.
  TERM AND
  TERMINATION
  6811.1
  Term
  6811.2
  Termination
  6911.3
  Consequences of
  Termination of Agreement
  7011.4
  Surviving Provisions
  7512.
  REPRESENTATIONS,
  WARRANTIES AND COVENANTS
  7612.1
  Mutual Representations and
  Warranties
  7612.2
  Additional Representations
  of SYNTA
  7612.3
  Additional Representations
  of GSK
  7712.4
  Covenants of GSK
  7812.5
  Covenants of Synta
  78   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.  ii


13.
  INDEMNIFICATION;
  INSURANCE
  7813.1
  Indemnification of SYNTA
  by GSK
  7813.2
  Indemnification of GSK by
  SYNTA
  7913.3
  Conditions to
  Indemnification
  7913.4
  Insurance
  7913.5
  Warranty Disclaimer
  7913.6
  No Warranty of Success
  8013.7
  Limited Liability
  8014.
  MISCELLANEOUS
  8014.1
  Arbitration
  8014.2
  Notices
  8114.3
  Governing Law
  8314.4
  Binding Effect
  8314.5
  Headings
  8314.6
  Counterparts
  8314.7
  Amendment; Waiver
  8314.8
  No Third Party
  Beneficiaries
  8314.9
  Purposes and Scope
  8314.10
  Assignment and Successors
  8414.11
  Force Majeure
  8514.12
  Interpretation
  8514.13
  Integration; Severability
  8514.14
  Further Assurances
  8514.15
  HSR Filing
  85  List of Exhibits and SchedulesExhibit A
  
  Form of
  Stock Purchase AgreementSchedule 1
  
  Description
  of STA-4783Schedule 2
  
  SYNTA
  Patent RightsSchedule 3
  
  ReservedSchedule 4
  
  Calculation
  and Mechanics for Payment of Operating Income (Loss) for the
  Co-Commercialization TerritorySchedule 5
  
  Form of
  Press ReleaseSchedule 6
  
  Material
  Terms to be Included in Co-Commercialization AgreementSchedule 7
  
  Principles
  Used for Determining Development Costs    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   iii


COLLABORATIVE DEVELOPMENT, COMMERCIALIZATION AND LICENSE AGREEMENT  This COLLABORATIVE DEVELOPMENT, COMMERCIALIZATION
AND LICENSE AGREEMENT (this Agreement) is entered into as of October 8,
2007 (the Execution Date) and effective as of the Effective Date (as defined
below), by and between Synta Pharmaceuticals Corp., a Delaware corporation with
offices at 45 Hartwell Avenue, Lexington, Massachusetts 02421 (SYNTA), and
SmithKline Beecham Corporation (doing business as GlaxoSmithKline), a
Pennsylvania corporation with offices at One Franklin Plaza, Philadelphia,
Pennsylvania 19101 (GSK).  Each of GSK
and SYNTA is sometimes referred to individually herein as a Party and
collectively as the Parties.  WHEREAS,
SYNTA has developed and Controls certain Patent Rights and Technology related
to Collaboration Compounds (as such terms are defined below); and  WHEREAS,
GSK has expertise in pharmaceutical research, development and
commercialization; and  WHEREAS,
the Parties desire to enter into a collaboration for the purpose of developing
and commercializing products containing a Collaboration Compound.  NOW,
THEREFORE, in consideration of the foregoing and the mutual covenants contained
herein, and for other good and valuable consideration, the Parties hereto agree
as follows:  1.DEFINITIONS  Whenever
used in this Agreement with an initial capital letter, the following terms
shall have the meanings specified below.  1.1Acceptance means, with respect to a
Drug Approval Application filed for a Product, (a) in the United States,
the receipt of written notice from the FDA in accordance with 21 CFR 314.101(a)(2) that
such Drug Approval Application is officially filed, (b) in the European
Union, receipt by GSK of written notice of acceptance by the EMEA of such Drug
Approval Application for filing under the centralized European procedure in
accordance with any feedback received from European Regulatory Authorities;
provided, that if the centralized filing procedure is not used, then Acceptance
shall be determined upon the acceptance of such Drug Approval Application by
the applicable Regulatory Authority in a Major European Country, and (c) in
Japan, receipt by GSK of written notice of acceptance of filing of such Drug
Approval Application from the Japanese Ministry of Health, Labour and Welfare (MHLW).  1.2Adverse Event means any unfavorable
and unintended change in the structure (signs), function (symptoms), or
chemistry (laboratory data), of the body temporally associated with the use of
a Product,whetheror not considered related to the use of the Product.Changes resulting from
normal growth and development which do not vary significantly in frequency or
severity from expected levels are not to be considered adverse experiences.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.


1.3Affiliate means, with respect to any
Person, any other Person that, directly or indirectly, controls, or is
controlled by, or is under common control with, such Person.  For purposes of this definition, control
means (a) the direct or indirect ownership of more than fifty percent (50%)
of the shares of stock entitled to vote for the election of directors in the
case of a corporation, or more than fifty percent (50%) of the equity interests
in the case of any other type of legal entity, or with respect to either of the
foregoing, such lesser maximum percentage permitted in those jurisdictions
where majority ownership by foreign entities is prohibited, (b) status as
a general partner in any partnership, or (c) any other arrangement whereby
a Person controls or has the right to control the board of directors of a
corporation or equivalent governing body of an entity other than a corporation.  1.4Aggregate Equity Purchase Price means (a) with
respect to the Initial Equity Purchase Obligation set forth in Section 6.2.1,
Twenty Five Million Dollars (US $25,000,000) and (b) with respect to the
Subsequent Equity Purchase Right set forth in Section 6.2.2, Twenty
Million Dollars (US $20,000,000).  1.5Annual Net Sales means, with respect
to any Calendar Year, the aggregate amount of the Net Sales for such Calendar
Year.  1.6API means the active pharmaceutical
ingredient known as STA-4783 and/or any other Collaboration Compound Developed
and Commercialized under this Agreement.  1.7Applicable Laws means any national,
supra-national, federal, state or local laws, treaties, statutes, ordinances, rules and
regulations, including any rules, regulations, guidance or guidelines having
the binding effect of law, or requirements of Regulatory Authorities, national
securities exchanges or securities listing organizations, government
authorities, courts, tribunals, agencies other than Regulatory Authorities,
legislative bodies and commissions that are in effect from time to time during
the Term and applicable to a particular activity hereunder.  1.8Applicable Premium means a premium
equal to [***] percent ([***]%).  1.9Average Closing Pricemeans the average of the closing prices of
SYNTA Common Stock on The NASDAQ Global Market (or, if SYNTA Common Stock is
not listed on the NASDAQ Global Market, the principal exchange or interdealer
quotation system on which the SYNTA Common Stock is listed) for the [***]
([***]) [***]to the [***] that gives rise to the Initial Equity Purchase
Obligation or the Subsequent Equity Purchase Right, as the case may be.  1.10Branding means all matters relating to
branding of any Product, including without limitation, any trademarks, brand
names, product logos, branding colors, trade dress, positioning and key
messages to be incorporated in promotional materials used for any Product.  1.11Business Day means any day other than
a Saturday or Sunday on which banking institutions in both New York, New York
and London, Englandare open for
business.  1.12Calendar Quarter means the period
beginning on the Effective Date and ending on the last day of the calendar
quarter in which the Effective Date falls, and thereafter   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application requesting
confidential treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   2


each successive period of
three (3) consecutive calendar months ending on March 31, June 30,
September 30 or December 31.  1.13Calendar Year means the period
beginning on the Effective Date and ending on December 31 of the calendar
year in which the Effective Date falls, and thereafter each successive period
of twelve (12) months commencing on January 1 and ending on December 31.  1.14Challengemeans any challenge to the validity or enforceability of any
of the SYNTA Patent Rights, including (except as provided below) by (a) filing
a declaratory judgment action in which any of the SYNTA Patent Rights is
alleged to be invalid or unenforceable; (b) citing prior art pursuant to
35 U.S.C. §301, filing a request for re-examination of any of the SYNTA Patent
Rights pursuant to 35 U.S.C. §302 and/or §311, or provoking or becoming a party
to an interference with an application for any of the SYNTA Patent Rights
pursuant to 35 U.S.C. §135; or (c) filing or commencing any
re-examination, opposition, cancellation, nullity or similar proceedings
against any of the SYNTA Patent Rights in any country; provided, that Challenge
shall not include filing requests for re-examination of SYNTA Patent Rights or
re-issue of SYNTA Patent Rights to the extent that JPC agrees that such actions
are in the best interest of the applicable SYNTA Patent Rights.  1.15Change of Control  means a transaction or series of related
transactions with a Pharmaceutical Company that results in (a) the holders
of outstanding voting securities of SYNTA immediately prior to such transaction
ceasing to represent at least fifty percent (50%) of the combined outstanding
voting power of the surviving entity immediately after such transaction; (b) such
Pharmaceutical Company becoming the beneficial owner of fifty percent (50%) or
more of the combined voting power of the outstanding securities of SYNTA; or (c) a
sale or other disposition to such Pharmaceutical Company of all or
substantially all of SYNTAs assets or business.  As used herein, Pharmaceutical Company
means any Person that, together with its Affiliates, has annual worldwide gross
sales of pharmaceutical products of at least [***] dollars ($[***]).  1.16Class 1 Covered Compoundmeans any compound that is covered by a
[***] claim of the Class 1 Patent.  1.17Class 1
Patentmeans the [***]  1.18Class 2 Covered Compoundmeans any compound that (a) is
covered by a [***] claim of the Class 2 Patent and (b) achieves its
[***].  As of the Effective Date, all
compounds covered by claims of the Class 2 Patent are Class 2 Covered
Compounds and shall remain Class 2 Covered Compounds until such time as SYNTA
can demonstrate to GSKs reasonable satisfaction that a compound covered by a
claim of the Class 2 Patent achieves its [***].  1.19Class 2 Patentmeans [***].  1.20Clinical Trialmeansa
clinical study of a Product involving the administration of Product to subjects
or patients for any Indication, and includes any Phase 1 Clinical Trial, Phase
2 Clinical Trial (including Phase 2a Clinical Trials and Phase 2b Clinical
Trials), Phase 3   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   3


Clinical
Trial, Optional Phase 4 Clinical Trial, Required Phase 4 Clinical Trial or
Collaborative Research Trial, as applicable.  1.21Collaboration means the alliance of
SYNTA and GSK established pursuant to this Agreement for the purposes of
Developing and Commercializing Products in the Territory.  1.22Collaboration Compound means,
collectively (a) STA-4783; (b) any [***] of STA-4783; (c) any
[***] of STA-4783; and (d) any other [***] STA-4783 and/or any of their
[***].  For purposes of this definition,
the term Collaboration Compound shall include all [***] not otherwise
described in Section 1.22(a)-(d) above only to the extent the Parties
agree to conduct Development of such [***] under this Agreement as set forth in
Section 8.4.4.  As used herein, an [***] of a
compound is a [***].  1.23Collaborative
Research Trial or CRTmeans an investigator-initiated pre-registrational or
post-registrational Clinical Trial of the Product in human patients that is notmandated by a Regulatory Authorityand is conducted for a purpose
other than to support an application to obtain Commercialization Regulatory
Approval for the use of a Product in a specified Indication in a country.  For purposes of clarity, a CRT may also be
known as an Investigator-Sponsored Trialor
an Investigator-Sponsored Study.  1.24Commercially Reasonable Efforts means,
with respect to activities of a Partyin
the Development, Manufacturing, Commercialization, or conduct of SYNTA
Co-Commercialization Activities or GSK Co-Commercialization Activities, as the
case may be, with respect to a particular Product, the [***] and [***] (or, if
a[***] in that [***] for other [***], by [***] and/or[***] that are [***] to
such [***]) in the [***]or [***] taking into account all relevant factors
including, as applicable and without limitation, [***]relative to [***] in the
[***] and extent of [***] (including [***] and likelihood of [***], and
[***].  For purposes of clarity,
Commercially Reasonable Efforts shall be determined on a [***] basis for a
particular Product, and it is anticipated that the [***].  1.25Commercialization or Commercialize means any and all
activities directed to the offering for sale or sale of a Product, both before
and after Commercialization Regulatory Approval has been obtained, including activities
related to marketing, promotion, distributing, Manufacturing commercial
supplies (other than Manufacturing Development or Manufacturing for use in
Development), importing, selling and offering to sell Product and/or conducting
Optional Phase 4 Clinical Trials with respect to any Indication with respect to
which Commercialization Regulatory Approval has been received or for a use that
is subject of a CRT, and interacting with Regulatory Authorities regarding the
foregoing.  When used as a verb, to
Commercialize and Commercializing means to engage in Commercialization and Commercialized
has a corresponding meaning.  1.26Commercialization
Regulatory Approval means, with respect to any Product, the
Regulatory Approval required by Applicable Laws to sell such Product for use
for an Indication in a country or region in the Territory, as well as, whether
or notrequired by Applicable Laws for the sale of
the Product, pricing approvals and government reimbursement approvals at a
level reasonably acceptable to GSK (in the Royalty-Bearing Territory) or to the    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   4


Parties
(in the Co-Commercialization Territory).For purposes of clarity, Commercialization
Regulatory Approval means (a) in the United States, final approval of an
NDA or sNDA permitting marketing of the applicable Product in interstate
commerce in the United States; (b) in the European Union, marketing
authorization for the applicable Product granted either by a Regulatory
Authority in any Major European Country or by the EMEA pursuant to Council
Directive 2001/83/EC, as amended, or Council Regulation 2309/93/EEC, as
amended, together with pricing approval and government reimbursement approval
at a level reasonably acceptable to GSK for the applicable Product granted by a
Regulatory Authority in any Major European Country; and (c) in Japan,
final approval of an application submitted to the MHLW and the publication of a
New Drug Approval Information Package permitting marketing of the applicable
Product in Japan, together with pricing approval and government reimbursement
approval at a level reasonably acceptable to GSK, as any of the foregoing may
be amended from time to time.  Pricing
and reimbursement in a particular country are conclusively deemed to have been
accepted by GSK with respect to a Product if GSK makes a First Commercial Sale
of such Product in such country.  1.27Completionmeans, with
respect to the [***], the date on which all material data reasonably expected
to be derived therefrom has been generated and the final study report with
respect thereto has been finalized.  1.28Confidential Information means (a) with
respect to SYNTA, (i) all tangible embodiments of SYNTA Technology and (ii) all
other information and Technology that is disclosed or provided by or on behalf
of SYNTA to GSK or to any of GSKs employees, consultants, Affiliates or
Sublicensees; (b) with respect to GSK, (i) all tangible embodiments
of GSK Technology and (ii) all other information and Technology that is
disclosed or provided by or on behalf of GSK to SYNTA or to any of SYNTAs
employees, consultants, Affiliates or sublicensees; and (c) with respect
to each Party, all tangible embodiments of Joint Technology; provided, that,
none of the foregoing shall be Confidential Information if: (A) as of the
date of disclosure, it is known to the receiving Party or its Affiliates as
demonstrated by contemporaneous credible written documentation, other than by
virtue of a prior confidential disclosure to such receiving Party; (B) as
of the date of disclosure it is in the public domain, or it subsequently enters
the public domain through no fault of the receiving Party; (C) it is
obtained by the receiving Party from a Third Party having a lawful right to
make such disclosure free from any obligation of confidentiality to the
disclosing Party; or (D) it is independently developed by or for the
receiving Party without reference to or use of any Confidential Information of
the disclosing Party as demonstrated by contemporaneous credible written
documentation.  Unless excluded from
Confidential Information pursuant to the proviso at the end of the preceding
sentence, any scientific, technical, manufacturing or financial information of
a Party that is disclosed at any meeting of the JSC, the JDC, the JCC or the
JPC shall constitute Confidential Information of the disclosing Party.  1.29Control or Controlled means with respect to
Technology or Patent Rights, the possession by a Party of the right to grant a
license or sublicense to such Technology or Patent Rights, or to supply
tangible embodiments of Technology as provided herein, without incurring
further obligations, or violating the terms of any agreement or arrangement
with any Third Party and without violating any Applicable Laws.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   5


1.30Co-Commercialization Territory means
the U.S. Territory if SYNTA has not exercised its Commercialization Opt-Out
Right.  1.31Co-Commercialized Product means a
Product for which the Parties are conducting SYNTA Co-Commercialization
Activities and GSK Co-Commercialization Activities, as the case may be, in the
Co-Commercialization Territory.  1.32Development or Develop means, with respect to each
Product, (a) all non-clinical, preclinical and clinical activities
designed to progress the development of Product with the objective of obtaining
Regulatory Approval of such Product in accordance with this Agreement up to and
including the obtaining of Commercialization Regulatory Approval of such
Product, including without limitation, toxicology, pharmacology and other
discovery and preclinical efforts, all activities relating to Manufacturing
Development, Clinical Trials (including Required Phase 4 Clinical Trials),
statistical analysis and all activities relating to obtaining Commercialization
Regulatory Approval.  When used as a
verb, Developing means to engage in Development and Developed has a
corresponding meaning.  For purposes of
clarity, Develop and Development shall not include the conduct of Optional
Phase 4 Clinical Trials or Collaborative Research Trials.  1.33Development Costs means the reasonable
out-of-pocket costs and internal costs incurred by a Party (or for its account
by an Affiliate or a Third Party) after the Effective Date that are consistent
with the respective Development activities of such Party in the applicable
Global Development Plan and budget and are directly attributable to the
Development of a Product and determined in accordance with Schedule 7
attached hereto.  For purposes of this
definition (a) [***] means the actual amounts paid to a [***] for specific
external Development activities applicable to a Product, including, without
limitation all [***] required for and other costs associated with, any [***]
and all expenses (including [***]) related to the [***] applicable to a Product
as provided in [***] until Commercialization Regulatory Approval is obtained; (b) internal
costs means the applicable FTE Rate multiplied by the number of FTE hours
utilized in the relevant period on activities directly relating to Development
in accordance with the Global Development Plan; and (c) the reasonable
out-of-pocket and internal costs shall include the cost of [***] for use in the
activities described in clause (a) or (b).  1.34Development Program means, with
respect to each Product, the Development activities (including the
Manufacturing Development activities) to be conducted by the Parties during the
Term with respect to such Product as set forth in the Global Development Plan.  1.35Drug Approval Application means, with
respect to each Product in a particular country or region, an application for
Commercialization Regulatory Approval for such Product in such country or
region, including without limitation: (a) an NDA, sNDA, MAA or JNDA; (b) a
counterpart of the foregoing in any country or region in the Territory; and (c) all
supplements and amendments to any of the foregoing.  1.36DMFmeansa Drug Master File maintained with the FDA or its equivalent maintained
with a RegulatoryAuthorityin
other countries within the Territory.   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.    6


1.37Effective Date means the date of
satisfaction of the HSR Conditions with respect to the transactions
contemplated by this Agreement, or if the Parties determine that an HSR Filing
is not required, then the Execution Date.  1.38EMEAmeans the
European Medicines Agency or any successor agency or authority thereto.  1.39Execution Date means the date set
forth in the Preamble.  1.40FDA means the United States Food and
Drug Administration or any successor agency or authority thereto.  1.41FDCA means the United States Federal
Food, Drug, and Cosmetic Act, as amended.  1.42First Commercial Sale means, with
respect to a Product in a country in the Territory, the first sale, transfer or
disposition for value to an end user of such Product in such country; provided,
that, the following shall not constitute a First Commercial Sale: (a) any
sale to an Affiliate or Sublicensee unless the Affiliate or Sublicensee is the
last entity in the distribution chain of the Product, (b) anyuse of a Product in Clinical Trials,
pre-clinical studies or other research or development activities, or disposal
or transfer of Products for a bona fide charitable purpose, (c) compassionate
use, (d) so called treatment IND sales and named patient sales, and (e) use
under the ATU system in France and/or the International Pharmi system in
Europe.  1.43Force Majeure means any occurrence
beyond the reasonable control of a Party that (a) prevents or
substantially interferes with the performance by such Party of any of its
obligations hereunder and (b) occurs by reason of any act of God, flood,
fire, explosion, earthquake, strike, lockout, labor dispute, casualty or
accident, or war, revolution, civil commotion, act of terrorism, blockage or
embargo, or any injunction, law, order, proclamation, regulation, ordinance,
demand or requirement of any government or of any subdivision, authority or
representative of any such government.  1.44FTE means one [***] hours of work devoted
to or in direct support of Development or Commercialization of Products in
accordance with a Global Development Plan or Product Co-Commercialization Plan
that is carried out by one or more employees or contract personnel of a Party
(other than [***]), measured in accordance with such Partys normal time
allocation practices from time to time and subject to audit by the other Party
in accordance with Section 3.5.3(b) and Schedule 6.  In no event shall an individual account for
more than one FTE year in any Calendar Year.  1.45FTE Cost means, for any period, the
FTE Rate multiplied by the number of FTEs in such period.  1.46FTE Rate means a rate of [***] dollars
($[***]) per FTE per annum for FTEs engaged in Development activities.  The FTE Rate shall be adjustedannually, commencing on [***], by the
percentage movement in theConsumer Price Index for all Urban Consumers
for the     Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   7


immediately preceding
Calendar Year, as published by the U.S. Department of Labor, Bureau of
Statistics.  1.47GAAP means United States generally
accepted accounting principles, consistently applied.  1.48Global Development Plan means, with
respect to each Product, the written plan for, and budget applicable to, the
Development activities to be conducted for such Product, as such written plan
may be amended, modified or updated in accordance with Section 3.1.2.For
purposes of clarity, it is the expectation of the Parties that the initial
Global Development Plan shall describe the Development activities to be
conducted for the three (3) year period commencing as of the Effective
Date and continuing until [***] and shall be reviewed and updated by the JSC
(and JDC with respect to the U.S. Territory) not less than once each Calendar
Year.  1.49GLP means the then current Good
Laboratory Practice Standards promulgated or endorsed by the FDA or in the case
of foreign jurisdictions, comparable regulatory standards promulgated or
endorsed by the applicable Regulatory Authority, including those procedures
expressed in or contemplated by any Regulatory Filings.  1.50GMP means current Good Manufacturing
Practices that apply to the Manufacture of API and clinical or commercial
supply of Product, including, without limitation, the United States regulations
set forth under Title 21 of the United States Code of Federal Regulations,
parts 210 and 211, as may be amended from time-to-time, as well as all
applicable guidance published from time-to-time by the FDA and the
International Conference on Harmonisation Guidelines ICHQ7A Good Manufacturing
Practice Guidance for API and/or the principles and guidelines of Good
Manufacturing Practices for Medicinal Products as defined with EC Directive
2003/94/EC and associated EC Guide to Good Manufacturing Practice.  1.51GSK Co-Commercialization Activities
means (a) with respect to the Co-Commercialized Product for the Indication
of [***], the following activities as deemed necessary by the JCC: (i) interactions
with [***]; (ii) [***] activities, including relevant [***] groups; (iii) the
conduct of [***]; (iv) interacting with and promoting Products to [***]; (v) interacting
with and promoting Products to [***]and [***]; (vi) the conduct of
operational activities with respect to Co-Commercialized Products, including
without limitation [***] management, management of [***], [***] management (for
both [***]) and [***], [***] programs, [***], [***], the maintenance of [***]
centers, [***] resource centers and [***] programs, administration matters,
[***], [***], sales [***], [***] management and [***] management; (vii) [***];
and (viii) [***] with SYNTA [***] [***] activities and (ix) taking a
role in defining the [***], [***] and [***] of the Product; and (b) with
respect to the Co-Commercialized Product for any Indication other than [***],
[***]; provided, that the activities set forth under Sections 1.51(a)(i),
(a)(iii), (a)(iv), (a)(vi), (a)(vii) and (a)(ix) shall [***] GSKs
responsibility for [***] Products in [***] Indications, subject to Section 8
of Schedule 6.  1.52GSK Decision means any [***] decision
that is not a [***] (other than as provided in Section 2.1.5)with respect to (a) the Development
and/or Commercialization of a    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   8


Product for [***]; (b) all
[***] matters with respect to the Commercialization of any Co-Commercialized
Product for any [***] Territory, including matters related to Sections
2.3.4(f), (h), (j) and (n)-(r); (c) all [***] of the Product; (d) all
[***] matters in the [***] Territory relating to [***] other than [***] and
other than the activities described in Section 3.1.3(b); provided, that
the foregoing shall become GSK Decisions at such time as the Commercialization
Regulatory Approval for the Product for the Indication of [***] is transferred
to GSK in accordance with the Regulatory Filings Transfer Plan; and provided,
further that all decisions related to the [***] portions of the Drug Approval
Application for the Product for the Indication of [***] shall be GSK Decisions
as of the Effective Date; (e) enforcement and defense of the [***]; (f) [***];
and (g) [***] of a [***] as described in Section 8.4.4 if [***] or if
the Parties are unable to [***]; provided, that any GSK Decision cannot (i) commit
SYNTA to perform any activity that conflicts with GSK Internal Policies (or
decisions of the GSK Global Clinical Safety Board) or Applicable Laws; (ii) conflict
with an approved Global Development Plan (as it relates to Development in the
U.S. Territory) or Product Co-Commercialization Plan; or (iii) be
detrimental to the global Branding applicable to a Product.  1.53GSK Development Activities means the
Development activities specified to be conducted by GSK in any Global
Development Plan.  1.54GSK Development Cost-Sharing Percentage
means [***] percent ([***]%).  1.55GSK Internal
Policies means the internal policies and procedures of GSK
applicable to the Development and/or Commercialization of Products which shall
be disclosed by GSK to SYNTA, and updated by GSK, pursuant to Section 12.4.1.  1.56GSK Operating Income (Loss) Sharing Percentage
means, forall Co-Commercialized
Products in each Calendar Year (a) [***] percent ([***]%) of the Operating
Income (Loss) for the first $[***] million of Net Sales in the
Co-Commercialization Territory in a Calendar Year and (ii) [***] percent
([***]%) of the Operating Income (Loss) for all additional Net Sales in the
Co-Commercialization Territory during such Calendar Year.  The GSK Operating Income (Loss) Sharing
Percentage shall be calculated pursuant to Section 5 of Schedule 4,
based on the weighted average percentage of either forecasted or actual (as
relevant) total Net Sales in the Co-Commercialization Territory in each
Calendar Year above and below $[***] million. 
For example, if Net Sales in a Calendar Year in the Co-Commercialization
Territory are $[***] million, then the GSK Operating Income (Loss) Percentage
for that Calendar Year would be [***]% ([***]) since [***] or [***] of the Net
Sales are below $[***] million and [***] or [***] of the Net Sales are above
$[***] million. For clarity, in any Calendar Year in which there are no Net
Sales (including Calendar Years prior to the Calendar Year in which the First
Commercial Sale occurs) in the Co-Commercialization Territory, but there are Commercialization
Expenses, the GSK Operating Income (Loss) Percentage applicable to the
resulting Operating Income (Loss) will be [***] percent ([***]%).  1.57GSK
Product Commercialization Plan means, with respect to
each Product, the written plan outlining material activities with respect to
the Commercialization of such Product by GSK in the Major Market Countries in
the Royalty-Bearing Territory.   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   9


1.58GSK Patent Rights means any Patent
Rights Controlled by GSK in the Territory during the Term that coverany aspect of the manufacture,use, sale,
offer for sale or importation of a Collaboration Compound or Product, including
without limitation any Patent Rights that claim GSK Technology.  1.59GSK Technology means any Technology,
including Program Technology other than Joint Technology, Controlled by GSK in
the Territory during the Term that is necessary or useful for the Development,
Manufacture, use or sale of any Collaboration Compound or Product.  1.60Hatch-Waxman Act means the Drug Price
Competition and Patent Term Restoration Act of 1984, as amended.  1.61HSR Actmeans the Hart-Scott-Rodino Antitrust Improvements Act of
1976, as amended.  1.62IND means (a) an Investigational
New Drug Application as defined in the FDCA and regulations promulgated
thereunder or any successor application or procedure required to initiate
clinical testing of a Product in humans in the United States; (b) a
counterpart of an Investigational New Drug Application that is required in any
other country or region in the Territory before beginning clinical testing of a
Product in humans in such country or region; and (c) all supplements and
amendments to any of the foregoing.  1.63Indication
means any human disease or condition which can be treated, prevented, cured or
the progression of which can be delayed. 
For purposes of the payment of milestones pursuant to Section 6.4.1,
with respect to SYNTAs Development Opt-Out Right (except as provided in Section 3.1.3(d))
and with respect to the definition of New Indication, the [***] for a Product
for a particular Indication, for example, the [***] of the use of a Product
from treating [***] to use as [***] treatment for [***] and/or the approval of
a Product as a [***] therapy after being approved as a [***] therapy for
treatment of the same disease or condition shall not be deemed to be separate
Indications.  1.64Initial Equity Purchase Obligation Date
means the [***] of (a) the date of determination by the JDC that the
Ongoing Clinical Trial has achieved its [***], or (b) the date of
determination by the JDC to file for Regulatory Approval in the U.S. Territory
for STA-4783 for metastatic melanoma despite not meeting the [***] in the
Ongoing[***]Clinical Trial.  For purposes
of this definition, the date of determination shall mean the date of any
meeting at which the applicable decision is made by the JDC pursuant to Section 2.2.3(b) (or
if such decision was a Disputed Matter, then the date on which the applicable
decision was finally decided).  1.65Initiation means, with respect to a
Clinical Trial, the first date that a subject or patient is dosed in such
Clinical Trial.  1.66JNDAmeans
a new drug application submitted to the MHLW to obtain Commercialization
Regulatory Approval for the marketing of a Product in Japan.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   10


1.67Joint Commercialization Committee or JCC means the committee comprised of
SYNTA and GSK representatives established pursuant to Section 2.3.  1.68Joint Development Committee or JDC means the committee composed of
SYNTA and GSKrepresentatives
established pursuant to Section 2.2.  1.69Joint
Patent Committeeor JPC
means the committee composed of SYNTA and GSK representatives established
pursuant to Section 2.5.  1.70Joint Patent Rights means Patent
Rights that contain one or more claims that cover Joint Technology.  1.71Joint Steering Committee or JSC means the committee composed of
SYNTA and GSK representatives established pursuant to Section 2.1.  1.72Joint Technology means any Program
Technology that is jointly conceived or reduced to practice by one or more
employees of or consultants to GSK and one or more employees of or consultants
to SYNTA.  1.73Knowledge or Known means, with respect to SYNTA,
the actual knowledge of the chief executive officer or any executive officer
(as defined for purposes of Section 14 of the Securities Exchange Act of
1934, as amended) of SYNTA.  1.74MAA means a Marketing
Authorization Application submitted to the EMEA to obtain European Commission
approval for the marketing of a Product in the European Union,or any
successor application or procedure required to sell a Product in the European
Union.  1.75Major Indication means each of [***].  1.76Major European Country means each of
the [***].  1.77Major Market Country means each ofthe [***].  1.78Manufacture or ManufacturingorManufacturedmeans all operations involved in the manufacture, receipt,
incoming inspections, storage and handling of materials, and the manufacture,
processing, purification, packaging, labeling, warehousing, quality control
testing (including in-process release and stability testing), shipping and
release of API or Product.  1.79Manufacturing Cost means with respect
to any Product Manufactured by or on behalf of GSK, GSKs costs of
Manufacturing such Product, which shall be the sum of the following components:
(a) direct costs, including manufacturing [***] directly used in
Manufacturing such Product by GSK or its Affiliates and allocated [***] of the
manufacturing department; (b) [***] of non-manufacturing departments (such
as quality and regulatory) attributable to such Product; (c) an allocation
of [***] used in Manufacture of Product; (d) [***] and other charges incurred
by GSK for outsourcing the Manufacture of the Product and the cost of [***]
manufacturers, and of [***] of the outsourced items, and (e) any other
[***] out-of-    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   11


pocket costs borne by GSK
for the [***] of such Product.  In the
event that GSK elects to Manufacture Product at a Manufacturing facility owned
and operated by GSK, then the costs set forth in clauses (a), (b) and (c) above
shall be pro-rated based on capacity utilized by GSK in the Manufacture of such
Product, as the case may be, or any intermediate thereof at such facility as
compared to the capacity used to Manufacture any other product or
intermediate.  For purposes of clarity (i) the
basis for all allocations under this Section shall be included in any invoice
for Manufacturing Costs and (ii) all allocations under this Section shall
be based on space occupied or head-count or other activity-based method.  1.80Manufacturing Development means, with
respect to API or Product, all activities related to the optimization of a
commercial-grade Manufacturing process for the Manufacture of API or Product
including, without limitation, test method development and stability testing,
formulation development, validation, productivity, trouble shooting and next
generation formulation, process development, Manufacturing scale-up,
development-stage Manufacturing, and quality assurance/quality control
development.  1.81Minor Indication means any Indication
that is not a Major Indication.  1.82NDA means a New Drug Application, as
defined in the FDCA and regulations promulgated thereunder or any successor
application or procedure required to sell a Product in the United States.  1.83Net Sales means the gross amount
billed or invoiced by GSK or any of its Affiliates or Sublicensees (each, a Seller)
to Third Parties throughout the Territory for sales or other dispositions or
transfers for value of Products less (a) allowances for normal and
customary [***] actually allowed and taken, (b) [***] paid by the Seller, (c) [***]
(regardless of the method for paying for such [***]), [***] pursuant to
agreements (including, without limitation, [***] agreements) or government
regulations, to the extent actually allowed, (d) [***] paid by the Seller
in relation to the Product and any other equivalent [***] imposed upon the
importation, use or sale of the Product, (e) [***] to customers on account
of retrospective price reductions affecting the Product, (f) the actual
amount of any [***] and (g)any
other [***] items actually deducted from gross invoiced sales amounts as
reported by GSK in its financial statements that are allocable to the sale or
disposition for value of Products in accordance with the International
Financial Reporting Standards (IFRS), applied on a consistent basis.  This definition of Net Sales may be updated
from time to time by GSK to reflect changes reasonably required by (i) the
adoption by GSK of accounting standards other than IFRS, due to GSKs merger
with another entity, or as required by Applicable Laws, or (ii) IFRS to
the extent GSK is utilizing IFRS as its accounting standard, from time to time;
provided, that, GSK shall promptly provide SYNTA with written notice of any
such updates.In addition,
Net Sales are subject to the following:  (A)          If the Seller or any of its Affiliates
effects a sale, disposition or transfer of a Product to a customer in a
particular country other than on customary commercial terms or as part of a
package of products and services, the Net Sales of such Product to such customer
shall be deemed to be the fair market value of such Product.  For purposes of this subsection (i), fair
market value means the value that would have been derived had such Product
been sold as a separate product to another customer in the country concerned on
customary commercial terms.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   12


(B)           In the case of pharmacy incentive
programs, hospital performance incentive program chargebacks,similar programs or discounts on products, all discounts
and the like shall be allocated among products on the basis on which such
discounts and the like were actually granted or, if such basis cannot be
determined, in proportion to the respective list prices of such products.  (C)           For purposes of clarity, (I) use
of any Product in Clinical Trials, pre-clinical studies or other research or
development activities, or disposal or transfer of Products for a bona fide
charitable purpose shall not give rise to any Net Sales and (II) use of
any Product in an early access program shall not give rise to any deemed sale
for purposes of this definition unless the Seller bills such program for such
Product at a price that exceeds [***] percent ([***]%) of the Sellers
Manufacturing Cost to supply such Product.  1.84Operating Income (Loss) has the
meaning set forth on Schedule 4 attached hereto.  1.85Ongoing Clinical Trial means the [***]which is
contained in the initial Global Development Plan.  1.86Optional Phase
4 Clinical Trial means a
post-registrational Clinical Trial of the Product in human patientsother than a registration trial or a trial
mandated by a Regulatory Authority, that is
not required as a condition to, or for the maintenance of, a Commercialization
Regulatory Approval for the use of a Product in a specified Indication in a
country.  1.87Patent Rights means the rights and
interests in and to issued patents and pending patent applications (which, for
purposes of this Agreement, include certificates of invention, applications for
certificates of invention and priority rights) in any country or region,
including all provisional applications, substitutions, continuations,
continuations-in-part, divisions, renewals, all letters patent granted thereon,
and all reissues, re-examinations and extensions thereof, and all foreign
counterparts of any of the foregoing.  1.88Permitted Transactions means any
agreement by and between a Party and (a) any Third Party pursuant to which
such Third Party conducts [***] permitted pursuant to Section 8.2.1(a) of
this Agreement or (b) any [***], which agreement provides for the [***]
under such agreement.  1.89Per Share Purchase Price means the sum
of (a) the Average Closing Price plus (b) the Applicable Premium
times the Average Closing Price.  1.90Person means an individual, sole proprietorship,
partnership, limited partnership, limited liability partnership, corporation,
limited liability company, business trust, joint stock company, trust,
incorporated association, joint venture or similar entity or organization,
including a government or political subdivision, department or agency of a
government.  1.91Pharmacovigilance
Agreement means the safety data exchange agreement relating to
the activities contemplated under this Agreement which the Parties will use
their    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   13


Commercially Reasonable Efforts to agree and enter into within [***]
([***]) days of the Effective Date of this Agreement.  1.92Phase 1 Clinical Trial means a
Clinical Trial in any country, the principal purpose of which is a preliminary
determination of safety in healthy individuals or patients that would satisfy
the requirements of 21 CFR 312.21(a), or an equivalent clinical study required
by a Regulatory Authority in a jurisdiction outside of the United States.  1.93Phase 2 Clinical
Trial means a Clinical Trial conducted in any country that is
intended to explore a variety of doses, dose response and duration of effect to
generate initial evidence of clinical safety and activity in a target patient
population, that would satisfy the requirements of 21 CFR 312.21(b), or an
equivalent clinical study required by a Regulatory Authority in a jurisdiction
outside of the United States.  1.94Phase
2a Clinical Trialmeans, as to a particular Product for any
New Indication, the portion of a Phase 2 Clinical Trial which contains a
sufficient number of subjects to generate sufficient data (if successful) to
commence a Phase 2b or a Phase 3 Clinical Trial of such Product for
such New Indication.  1.95Phase 2b Clinical Trialmeans, as to a
particular Product for any New Indication, the portion of a Phase 2 Clinical
Trial which contains a sufficient number of subjects to generate sufficient
data (if successful) to either (i) commence a Phase 3 Clinical Trial of
such Product for such New Indication or (ii) file a Drug Approval
Application for such Product for such New Indication.  1.96Phase 3 Clinical Trial meansa Clinical
Trial in any country performed after preliminary evidence of efficacy has been
obtained, which if successful, provides sufficient evidence of the safety and
efficacy of a product to support a Commercialization Regulatory Approval, and
that would satisfy the requirements of 21 CFR312.21(c),or an equivalent clinical study required by
Regulatory Authority in a jurisdiction outside of the United States.  1.97Pricing means the determination of
Product pricing at all levels, including the Product list price (also referred
to as Wholesale Acquisition Cost) and the net price in which the Product is
offered to various purchasers and payers (private sector and government
entities).  1.98Product means any pharmaceutical or
medicinal item, substance, formulation or dosage for sale by prescription, over-the-counter, or any other method, which
is comprised of or contains a Collaboration Compound (whether or not such
Collaboration Compound is the sole active ingredient).  For purposes of clarity, Product includes
Co-Commercialized Products and Royalty-Bearing Products.  1.99Product Co-Commercialization Plan
means, with respect to a Co-Commercialization Product, the written plan for the
commercialization (including the GSK Co-Commercialization Activities and SYNTA
Co-Commercialization Activities) of such Product in the Co-Commercialization
Territory (including, without limitation, expected Manufacturing requirements
and a detailed [***], budget and proposed timelines), as such plan may be
amended or updated.  Each Product
Co-Commercialization Plan shall include, without limitation, (a)    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   14


demographics and market
dynamics, market [***], a marketing plan (including advertising, detailing
forecasts, [***] pertaining to [***] and sales forecasts); (b) the
specific Commercialization objectives, projected milestones, resource
allocation requirements and activities to be performed over such period
(including, without limitation, all anticipated Clinical Trials); (c) the
Party responsible for such activities; (d) an expected non-binding
timeline for such activities, including the estimated launch date(s); (e) a
non-binding sales and expense forecast (including at least [***] ([***]) years
of estimated sales and expenses); (f) Manufacturing plans and the expected
product profile; (g) a Commercialization
Budget including a budget of the expenses expected to be
incurred in performing all activities therein contained, as well as any Third
Parties proposed to be utilized and, to the extent applicable, any proposed
Third Party arrangements; and (h) the expected Regulatory Filings to be
required and prepared, and the expected timetable for making such Regulatory
Filings.  Each Product
Co-Commercialization Plan, and each amendment, modification or update to each
Product Co-Commercialization Plan, shall be prepared by, or at the direction
of, the JCC, and approved by the JSC at such time as the JSC may from time to
time direct and in any event, on or prior to the initiation of
Commercialization activities with respect to the Product.  1.100Product Trademark means any trademark
or trade name, whether or not registered, or any trademark application or
renewal, extension or modification thereof, in the Territory, or any trade
dress and packaging applied to or used with any Product together with all
goodwill associated therewith.  1.101Program Technology means any Technology
relating to a Collaboration Compound (including, without limitation, any new
and useful process, synthesis, formulation, delivery, method of manufacture or
composition of matter) that is conceived and first reduced to practice by
either Party or jointly by both Parties in the conduct of the Collaboration.  1.102Promotional Efforts means with respect
to a Co-Commercialized Product, an interactive, personal, live, contact of a
Representative within the Co-Commercialization Territory with a medical
professional with prescribing authority, an individual who is part of the
applicable treatment team for an Indication or other individuals or entities
that have a significant impact or influence on prescribing decisions, in an
effort to influence physician prescribing preferences of such Co-Commercialized
Product for its approved uses within the Co-Commercialization Territory.  1.103Proof of Concept Clinical Trial means
a Phase 2b Clinical Trial that is designed to determine whether a Collaboration
Compound satisfies the Proof of Concept Criteria for a specific
Indication.  A Proof of Concept Clinical
Trial shall be designed to be in keeping with industry practices in terms of
number of participants, number of sites, duration of the study, number of arms
in the study and total anticipated cost of the study.  1.104Proof of Concept Criteria means the
criteria that will be determined by the JDC and used to determine if a
Collaboration Compound demonstrates a [***] in treating a specific Indication
in a Proof of Concept Clinical Trial. 
Proof of Concept Criteria may also include certain non-clinical studies
and assessments as the JDC may determine are appropriate.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   15


1.105Regulatory Approval means, with
respect to any country or region in the Territory, any approval, product and
establishment license, registration or authorization of any Regulatory
Authority required for the Manufacture, use, storage, importation, exportation,
transport or distribution of a Product in such country or region, excluding price and reimbursement approval.  1.106Regulatory Authority means any
national, supra-national, regional, state or local regulatory agency,
department, bureau, commission, council or other governmental entity with
authority over the distribution, importation, exportation, Manufacture,
production, use, storage, transport, clinical testing, pricing or sale of a
Product, including without limitation, the FDA, EMEA, European Commission and
the MHLW.  1.107Regulatory Filings means,
collectively: (a) all INDs, NDAs, MAAs, JNDAs, BLAs, establishment license
applications, DMFs, applications for designation as an Orphan Product(s)
under the Orphan Drug Act, for Fast Track status under Section 506 of
the FDCA (21 U.S.C. § 356) or for a Special Protocol Assessment under Section 505(b)(4)(B) and
(C) of the FDCA (21 U.S.C. § 355(b)(4)(B)) and all other similar filings
(including, without limitation, counterparts of any of the foregoing or
Scientific Advice in any country or region in the Territory); and (b) all
supplements and amendments to any of the foregoing.  1.108Required Phase 4 Clinical Trialmeans
a post-registrational Clinical Trial of Products in human patients that is
required as a condition to, or for the maintenance of, a Commercialization
Regulatory Approval for the use of Product in a specified Indication in a
country.  1.109ROW Territory means all of the
countries and territories of the world other than the U.S. Territory.  1.110Royalty-Bearing Product means any
Product that is sold by GSK in the Royalty-Bearing Territory.  1.111Royalty-Bearing Territory means (a) the
ROW Territory and (b) the U.S. Territory in the event that SYNTA exercises
the Commercialization Opt-Out Right with respect to a Product or otherwise
loses the right to conduct SYNTA Co-Commercialization Activities with respect
to a Product under this Agreement.  1.112Royalty Term means with respect to
each Royalty-Bearing Product in each country in the Royalty-Bearing Territory,
the period beginning on the date of First Commercial Sale of such
Royalty-Bearing Product in such country and ending on the later to occur of (a) the
expiration of the last to expire Valid Claim of the SYNTA Patent Rights or
Joint Patent Rights in such country that covers the composition of matter,
sale, import or use of the Collaboration Compound contained in such
Royalty-Bearing Product, and (b) [***] years from the date of the First
Commercial Sale of such Royalty-Bearing Product in such country.  1.113Share Purchase Number means (a) with
respect to the Initial Equity Purchase Obligation, the number of shares of
SYNTA Common Stock as shall equal Twenty Five Million Dollars (US $25,000,000)
divided by the Per Share Purchase Price and (b) with respect to the    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   16


Subsequent Equity Purchase
Right, the number of shares of SYNTA Common Stock as shall equal Twenty Million
Dollars (US $20,000,000) divided by the Per Share Purchase Price.  1.114sNDA means a Supplemental New Drug
Application, as defined in the FDCA and applicable regulations promulgated
thereunder.  1.115STA-4783 means the compoundControlled by SYNTA and described more
fully on Schedule 1 attached hereto.  1.116Sublicensee means any Third Party to
which a Party grants a sublicense in accordance with Section 8.2.  1.117Subsequent Equity Purchase Right Date
means the date on which written notification of Regulatory Approval for an NDA
or MAA is first received in one of either the United States, the European Union
or two Major European Countriesfor
the first to occur of either (a) the second Indication for a Product or (b) the
first Indication for the second Product.  1.118SYNTA
Co-Commercialization Activities means, (i) with respect to
the Co-Commercialized Product for the Indication of metastatic melanoma, the
following activities as deemed necessary by the JCC: (a) the lead role in
the conduct of interactions with [***]; (b) the lead role in interacting
with [***] organizations and the [***]; (c) the lead role in defining the
market [***], [***] management and [***] of the Product to be presented to the
JCC; (d) establishing and maintaining relationships with [***] groups; (e) the
responsibility for coordinating Optional Phase 4 Clinical Trials and
Collaborative Research Trials; (f) fielding a Medical Science Liaisons
(MSL) group; and (g) sponsoring and/or co-sponsoring with GSK [***]
activities and (ii) with respect to the Co-Commercialized Product for any
Indication other than metastatic melanoma, such [***].  1.119SYNTA Decisionmeans any decision that is not a [***]
with respect to [***] matters relating to the Development or Commercialization
of any Co-Commercialized Product for any Indication in the Co-Commercialization
Territory, including matters related to Sections 2.3.4(e) and (g), but
excluding decisions relating to the [***] portion of the Drug Approval
Application for the Product for the Indication of [***] in the U.S. Territory;
provided, that any SYNTA Decision cannot (a) result in an increase of more
than [***] percent ([***]%) in any annual budget applicable to a Product; (b) commit
GSK to perform any activity that conflicts with GSK Internal Policies (or
decisions of the GSK Global Clinical Safety Board) or Applicable Laws; (c) conflict
with an approved Global Development Plan or Product Co-Commercialization Plan;
or (d) be detrimental to the global Branding applicable to a Product.  1.120SYNTA Development Activities means the
Development activities specified to be conducted by SYNTA in any Global
Development Plan.  1.121SYNTA Development Cost-Sharing Percentage
means [***] percent ([***]%).  1.122SYNTA
Operating Income (Loss) Sharing Percentage means, with respect
to each Co-Commercialized Product, the result, expressed as a percentage,
obtained by subtracting    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   17


the GSK Operating Income (Loss) Percentage
applicable to that Co-Commercialized Product from one hundred percent (100%).  1.123SYNTA Patent
Rights means any Patent Rights Controlled by SYNTA in the
Territory during the Term that cover any aspect of the manufacture,use, sale,
offer for sale or importation of a Collaboration Compound or Product, including
without limitation any Patent Rights that claim SYNTA Technology.  The SYNTA Patent Rights existing as of the
Execution Date include, without limitation, the Patent Rights listed on Schedule
2 attached hereto, and shall, unless otherwise determined by the JPC, be
updated by SYNTA not less than [***]; provided, that such updates will be
provided not less than [***] following the First Commercial Sale of a Product.  1.124SYNTA Technology means any Technology,
including Program Technology other than Joint Technology, Controlled by SYNTA
in the Territory during the Term that is necessary or useful for purposes of
the Development, Manufacture, use or sale of any Collaboration Compound or
Product.  1.125Technology means, collectively,
inventions, discoveries, improvements, trade secrets, tangible chemical,
biological or physical materials and proprietary methods, whether or not
patentable, including without limitation: (a) methods of Manufacture or
use of, and structural and functional information pertaining to, chemical
compounds and (b) compositions of matter, data, formulations, processes,
techniques, know-how and results (including any negative results).  1.126Technology Transfermeans the
provision by one Party of technical assistance, manufacturing and analytical
know-how, and material specifications to enable the transfer of Technology
necessary for the other Party or its contract manufacturers to commence
Manufacture of commercial supply requirements of API and Product to meet the
relevant specifications, applicable legal and regulatory requirements in
accordance with mutually agreed transfer protocols and acceptance criteria.  1.127Territory means all countries and
territories of the world.  1.128Third Party means a Person other than
GSK and SYNTA and their respective Affiliates and Sublicensees.  1.129Third
Party Agreementsmeans the (a) [***] and SYNTA, dated
[***] and (b) the [***] and SYNTA, dated [***].  1.130Third Party Data Providermeans IMS Health and/or any other Third
Party approved by the JSC that performs market analyses and provides sales data
for the biotechnology or pharmaceutical industry.  1.131Unanimous Decisionmeans (a) any SYNTA Decision that
would result in an increase of more than [***] percent ([***]%) in any annual
Development or Commercialization budget applicable to a Product; (b) a GSK
Decision or SYNTA Decision that would (i) commit either Party to perform
any activity that conflicts with the GSK Internal Policies (including without
limitation decisions of the GSK Global Clinical Safety Board) or Applicable
Laws; (ii)    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   18


conflict with an approved
Global Development Plan (as it relates to Development in the U.S. Territory) or
Product Co-Commercialization Plan; or (iii) be detrimental to the global
Branding applicable to a Product; (c) any dispute with respect to the
negotiation and execution by the Parties of the Co-Commercialization Agreement
pursuant to Section 5.1.1(b); and (d) any decision with respect to
any of the following matters: (i) [***] for Products in the U.S.
Territory, (ii) [***] of a [***] [***] as described in Section 8.4.4
except as set forth in Section 1.52(g), (iii) decisions pertaining to
Section 2.2.4(i), Sections 2.3.4(a)-(b), Section 2.3.4(c) except
as it pertains to the matters under Section 2.3.4(f) which are GSK
Decisions, Section 2.3.4(d), Section 2.3.4(i) and Section 2.3.4(s)-(t),
(iv) approval of the initial [***], (v) the conduct of [***], [***]
or [***], (vi) the conduct of the [***] proposed by SYNTA and the protocol
design for the [***], (vii) the conduct of the  [***] proposed by SYNTA, the protocol design
for each [***] proposed by SYNTA, the protocol design for the [***], (ix) any
decision to progress [***] as set forth in Sections 3.1.3(b)-(c), (x) the
conduct of Development in a [***] pursuant to Section 3.1.3(c), the
protocol design for each new [***] and (xi) decisions regarding the
prosecution, maintenance and filing of [***] derived from the initial utility
application from which the Class 1 Patent and the Class 2 Patent were
derived, and (xii) a determination that the [***] of STA-4783 has been
identified. For clarity, in the event that the Parties do not unanimously agree
to progress Development into Phase 3, then GSK shall be permitted to continue
on its own subject to Section 3.1.3(d), or terminate such Development.  1.132U.S. Territorymeans the fifty states of the United
States of America and the District of Columbia.  1.133Valid Claim means any claim of a
pending patent application (only if the claim at issue has been pending for
less than [***] years from the date of the first official action) or an issued
unexpired patent that (a) has not been finally (i) cancelled, (ii) withdrawn,
(iii) abandoned or (iv) rejected by any administrative agency or
other body of competent jurisdiction, (b) has not been permanently
revoked, held invalid, or declared unpatentable or unenforceable in a decision
of a court or other body of competent jurisdiction that is unappealable or
unappealed within the time allowed for appeal, (c) has not been rendered
unenforceable through terminal disclaimer or otherwise, and (d) is not
lost through an interference proceeding that is unappealable or unappealed
within the time allowed for appeal.  Additional Definitions.  In addition, each of the following
definitions shall have the respective meanings set forth in the section of this
Agreement indicated below:  Definition
  
  SectionAAA
  
  14.1Abandoning
  Party
  
  10.1.4Action
  
  10.2.1(a)(ii)Agreement
  
  PreambleAlliance
  Manager
  
  2.4Annual
  Estimate
  
  Schedule
  4Applicable
  Reversion Royalty Rate
  
  11.3.1(b)Appointing
  Party
  
  2.7
   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   19


Definition
  
  SectionArbitration
  Matter
  
  14.1Assuming
  Party
  
  10.1.4Audited
  Party
  
  Schedule
  4Auditing
  Party
  
  Schedule
  4Change
  of Control Notice
  
  14.10Claims
  
  13.1Co-Commercialization
  Agreement
  
  5.1.1(b)Co-Commercialization
  Net Sales
  
  Schedule
  4Combination
  Product
  
  6.5.1(c)(iii)Commercialization
  Activities Transition Notice
  
  Schedule
  6Commercialization
  Opt-Out Date
  
  5.1.1(c)Commercialization
  Opt-Out Right
  
  5.1.1(c)Commercialization
  Transition Plan
  
  Schedule
  6Competing
  Drug
  
  6.5.1(c)(iv)Co-Commercialization
  Trademarks
  
  10.3.1Cost
  Audited Party
  
  3.6.2(b)Cost
  Auditing Party
  
  3.6.2(b)Development
  Opt-Out Notice
  
  3.1.3(d)Development
  Opt-Out Right
  
  3.1.3(d)Disputed
  Matter
  
  2.1.5Estimate
  
  Schedule
  4Estimated
  Loss
  
  Schedule
  4Estimated
  Operating Income Payment
  
  Schedule
  4Execution
  Date
  
  PreambleGSK
  
  PreambleGSK
  Indemnitees
  
  13.2GSK
  Manufacturing Know-How
  
  11.3.1(d)GSKs
  Brand
  
  10.3.4HSR
  Conditions
  
  14.15.2HSR
  Filing
  
  14.15.1Indemnified
  Party
  
  13.3Indemnifying
  Party
  
  13.3Infringement
  
  10.2.1(a)(i)Initial
  Co-Commercialization Period
  
  Schedule
  4Initial
  Equity Purchase Obligation
  
  6.2.1Initial
  Product Co-Commercialization Plan
  
  5.3(a)Losses
  
  13.1MHLW
  
  1.1MTD
  
  3.1.3(b)MTD
  Study
  
  3.1.3(b)Negotiation
  Period
  
  5.1.1(b)New
  Indication
  
  3.1.3(b)New
  Phase 2a Clinical Trial
  
  3.1.3(b)New
  Phase 2b Clinical Trial
  
  3.1.3(b)
   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   20


Definition
  
  Sectionnon-Appointing
  Party
  
  2.7Operating
  Income Payments
  
  Schedule
  4Opt-Out
  Indication
  
  3.1.3(d)Other
  Products
  
  6.5.1(c)(ii)Party/Parties
  
  PreamblePhase
  2a Success Criteria
  
  3.1.3(b)(i)Phase
  2b Success Criteria
  
  3.1.3(b)(ii)Publication
  Committee
  
  7.3Recipient
  Party
  
  3.5.1Region
  
  11.2.1(a)(ii)Regulatory
  Filings Transfer Plan
  
  4.1Representative
  
  Schedule
  6Reverted
  Royalty-Bearing Product
  
  11.3.1(b)Stock
  Purchase Agreement
  
  6.2.1Subsequent
  Equity Purchase Right
  
  6.2.2SYNTA
  
  PreambleSYNTA
  Common Stock
  
  6.2.1SYNTA
  Indemnitees
  
  13.1SYNTAs
  Brand
  
  10.3.4Term
  
  11.1Transferring
  Party
  
  3.5.1True-Up
  Operating Income Payment
  
  Schedule
  4Valid
  Safety Issue
  
  11.2.1(a)(iii)
  2.ADMINISTRATION OF THE COLLABORATION  2.1           Joint
Steering Committee.  2.1.1Establishment.As soon as practicable but in any event
within [***] Business Days after the Effective Date, SYNTA and GSK shall
establish the JSC.  The JSC shall have
and perform the responsibilities set forth in Section 2.1.4.  2.1.2Membership.Each of SYNTA and GSK shall
designate in writing an equal number (not less than [***]) of representatives
to the JSC, who shall be senior level personnel.For
the one (1) year period beginning on the establishment of the JSC, a SYNTA
representative to the JSC shall serve as the chairperson of the JSC.  For each subsequent one-year period,
representatives of the Parties shall alternate as the chairperson of the
JSC.Each Party shall have the
right at any time to substitute individuals, on a permanent or temporary basis,
for any of its previously designated representatives to the JSC by giving
written notice to the other Party.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   21


2.1.3        Meetings.  (a)           Schedule of Meetings; Agenda.  The first meeting of the JSC shall take place
within [***] days of the Effective Date. 
Thereafter, the JSC shall meet on a [***] basis, or more or less
frequently as agreed, taking into account, without limitation, the planning
needs of the Development Program and the Commercialization of Products and the
responsibilities of the JSC.  Special
meetings of the JSC may be convened by either Party upon not less than [***]
days (or, if such meeting is proposed to be conducted by teleconference, upon
not less than [***] days) written notice to the other members; provided, that
notice of any such special meeting may be waived at any time if mutually agreed
by the Parties.  Regular and special meetings
of the JSC may be held in person or by teleconference or videoconference;
provided, that, meetings held in person shall alternate between the respective
offices of the Parties in Lexington, Massachusetts and Philadelphia,
Pennsylvania or at other locations mutually agreeable to the JSC members.  The Alliance Manager from the opposing Party
to the chairperson shall be the designated secretary at meetings of the JSC and
shall be responsible for preparing and circulating to each JSC member an agenda
for each JSC meeting not later than [***] prior to such meeting.  (b)           Quorum; Voting; Decisions.  At each JSC meeting, (i) the presence in
person of at least [***] designated by each Party shall constitute a quorum and
(ii) the representatives of a Party shall have [***] on all matters before
the JSC at such meeting.  All decisions
of the JSC shall be made by [***] vote. 
Alternatively, the JSC may act by written consent signed by at least
[***] designated by each Party.  Whenever
any action by the JSC is called for hereunder during a time period in which the
JSC is not scheduled to meet, the chairperson shall cause the JSC to take the
action in the requested time period by calling a special meeting or by
circulating a written consent. 
Representatives of each Party or of its Affiliates who are not members
of the JSC (including, without limitation, members of the JPC, financial
representatives and Alliance Managers) may attend JSC meetings as non-voting
observers as appropriate for the agenda.  (c)           Minutes.  The designated secretary shall keep minutes
of all meetings that record all decisions and all actions recommended or taken
in reasonable detail.  Drafts of the
minutes shall be prepared and circulated to the members of the JSC within a
reasonable time after the meeting, not to exceed [***] Business Days.  Each member of the JSC shall have the
opportunity to provide comments on the draft minutes.  Final minutes of each meeting shall be
approved as the first order of business at the subsequent JSC meeting.  (d)           Expenses.  SYNTA and GSK shall each bear all expenses of
their respective JSC representatives related to their participation on the JSC
and attendance at JSC meetings and shall not be Development Costs or
Commercialization Expenses for purposes of this Agreement.  2.1.4Responsibilities.The JSC shall be responsible
for overseeing the conduct and progress of the global Development Program, and
specifically the Development and Commercialization of Products in the U.S.
Territory.  In addition, the JSC will
receive updates from GSK with respect to Development and Commercialization of
Products in the ROW    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   22


Territory; provided that
such updates are meant to be informational only and not subject to the JSCs
approval.  Without limiting the
generality of the foregoing, the JSC shall have the following responsibilities:  (a)           overseeing the
activities and performance by each of the JDC and the JCC of its respective
responsibilities;  (b)           reviewing the GSK
Internal Policies applicable to the Development and/or Commercialization
activities being conducted under the Agreement, as in effect on the Effective
Date and as updated by GSK from time to time;  (c)           reviewing data,
reports or other information submitted to it by the JDC or the JCCfrom time to time;  (d)           reviewing on a [***]
basis updates of material activities conducted by or on behalf of GSK with
respect to the Development and Commercialization of Products in each Major
Market Country in the ROW Territory;  (e)           reviewing and
approving each Global Development Plan and budget, the Product
Co-Commercialization Plan and Commercialization Budget and the Regulatory
Filings Transfer Plan;  (f)            resolving all JDC
or JCC matters that are in dispute; and  (g)           making such other
decisions as may be delegated to the JSC pursuant to this Agreement or by
mutual written agreement of the Parties during the Term.  2.1.5Dispute
Resolution.  The JSC
members shall use reasonable efforts to reach agreement on any and all
matters.  If, despite such reasonable
efforts, agreement on a particular matter cannot be reached by the JSC within
[***] days after the JSC first meets to consider such matter or such later date
as may be mutually acceptable to the Parties (each such matter, a Disputed
Matter), then the JSC shall refer such Disputed Matter to the Chairman,
Research & Development or Chief Operational Officer, Pharmaceuticals
(or their respective designees), for GSK and the Chief Executive Officer (or
his designee) for SYNTA who shall promptly initiate discussions in good faith
to resolve such Disputed Matter.  If the
Disputed Matter is not resolved by the aforementioned senior executives within
[***] days of the date the Disputed Matter is first referred to the senior
executives for resolution, then (a) if the Disputed Matter involves a SYNTA
Decision, the Chief Executive Officer of SYNTA shall have the right to make the
final decision on such Disputed Matter, but shall only exercise such right in
good faith after full consideration of the positions of both Parties and shall
not be submitted to arbitration for resolution pursuant to Section 14.1; (b) if
the Disputed Matter involves a GSKDecision,
the Chairman, Research & Development or Chief Operational Officer,
Pharmaceuticals (or their respective designees), of GSK (as appropriate) shall have
the right to make the final decision on such Disputed Matter, but shall only
exercise such right in good faith after full consideration of the positions of
both Parties and shall not be submitted to arbitration for resolution pursuant
to Section 14.1; (c) if the Disputed Matter involves a Unanimous
Decision,such Disputed Matter must
be resolved promptly by consensus of the JSC or the    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   23


foregoing
officers and shall not be submitted to arbitration for resolution pursuant to Section 14.1;
and (d) if the Disputed Matter involves any other matter, such Disputed
Matter shall be submitted to arbitration for resolution pursuant to Section 14.1.
If a Unanimous Decision set forth in Section 1.131(d)(ii) (subject to
Section 1.52(g)) or Section 1.131(d)(ix) cannot be resolved by
the JSC or the officers as described in Section 2.1.5(c) within [***]
days of referral thereto, then such Unanimous Decisions will be finally decided
by GSK. Notwithstanding the foregoing, where, as a result of Disputed Matters
that have been decided pursuant to Section 2.1.5(a) or (b), the Party
who was not responsible for making such decision reasonably believes the other
Partys decision would result in a material breach of this Agreement, then, the
non-deciding Party may, after providing the deciding Party with written notice
describing such reasonable belief, provide the deciding Party with a notice of
breach pursuant to Section 11.2.2 or seek a declaratory judgment that such
decision would result in a breach of this Agreement.  2.2           Joint
Development Committee.  2.2.1Establishment;
Term.As soon as
practicable but in any event within [***] Business Days after the Effective
Date, SYNTA and GSK shall establish the JDC. 
The JDC shall have and perform the responsibilities set forth in Section 2.2.4.  Unless otherwise agreed by the Parties, the
term for the JDC shall commence on the date it is established by the Parties
and continue until the JSC determines to discontinue the JDC as a result of the
completion of all Development activities for Products.  2.2.2Membership.Each of SYNTA and GSK shall
designate in writing an equal number (not less than [***]) of representatives
to the JDC.For a one (1) year period beginning on the establishment of the
JDC, a SYNTA representative to the JSC shall serve as the chairperson of the
JDC.  For each subsequent one-year
period, representatives of the Parties shall alternate as the chairperson of
the JDC.  Each Party shall have the
right at any time to substitute individuals, on a permanent or temporary basis,
for any of its previously designated representatives to the JDC by giving
written notice to the other Party.  2.2.3        Meetings.  (a)           Schedule of
Meetings; Agenda.  The first meeting
of the JDC shall take place within [***] days of the Effective Date.  Thereafter, the JDC shall meet on a [***]
basis, or more or less frequently as agreed, taking into account, without
limitation, the planning needs of the Development Program and the
responsibilities of the JDC.  Special
meetings of the JDC may be convened by either Party upon not less than [***]
days (or, if such meeting is proposed to be conducted by teleconference, upon
not less than [***] days) written notice to the other members; provided, that
notice of any such special meeting may be waived at any time if mutually agreed
by the Parties.  Regular and special
meetings of the JDC may be held in person or by teleconference or
videoconference; provided, that, meetings held in person shall alternate
between the respective offices of the Parties in Lexington, Massachusetts and
Philadelphia, Pennsylvania or at other locations mutually agreeable to the JDC
members.  A designated secretary from the
opposing Party to the chairperson shall be responsible for preparing and circulating
to each JDC member an agenda for each JDC meeting not later than [***] prior to
such meeting.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   24


(b)           Quorum; Voting;
Decisions.  At each JDC meeting, (i) the
presence in person of at least[***] designated by each Party
shall constitute a quorum and (ii) the representatives of a Party shall
have [***] on all matters before the JDC at such meeting.  All decisions of the JDC, shall be made by
[***] vote.  Alternatively, the JDC may
act by written consent signed by at least [***]designated by
each Party.  Whenever any action by the
JDC is called for hereunder during a time period in which the JDC is not
scheduled to meet, the chairperson shall cause the JDC to take the action in
the requested time period by calling a special meeting or by circulating a
written consent.  Representatives of each
Party or of its Affiliates who are not members of the JDC (including, without
limitation, members of the JPC, financial representatives and Alliance
Managers) may attend JDC meetings as non-voting observers.  In the event that the JDC is unable to
resolve any matter before it, such matter shall be resolved in accordance with Section 2.2.5.  (c)           Minutes.  The designated secretary shall keep minutes
of all meetings that record all decisions and all actions recommended or taken
in reasonable detail.  Drafts of the
minutes shall be prepared and circulated to the members of the JDC within a
reasonable time after the meeting, not to exceed [***] Business Days.  Each member of the JDC shall have the
opportunity to provide comments on the draft minutes.  Final minutes of each meeting shall be
approved as the first order of business at the subsequent JDC meeting.  (d)           Expenses.  SYNTA and GSK shall each bear all expenses of
their respective JDC representatives related to their participation on the JDC
and attendance at JDC meetings and such expenses shall not be Development Costs
or Commercialization Expenses for purposes of this Agreement.  2.2.4        Responsibilities.  The JDC shall be responsible for overseeing
the conduct and progress of the Development Program and theDevelopmentof Products in the U.S. Territory.  For purposes of clarity, where this Agreement
provides for the JDC to have oversight over any Development applicable to the
U.S. Territory, but not conducted in the U.S. Territory, such oversight shall
be solely limited to the conduct of the Ongoing Clinical Trial or any other
Clinical Trial in the ROW Territory intended to support registration in the
U.S. Territory.  The JDC shall have the
following responsibilities:  (a)           preparing, or
directing the preparation by the Parties of, that portion of each Global
Development Plan applicable to the Development of Products in the U.S.
Territory, including the budget with respect thereto;  (b)           preparing, or
directing the preparation by the Parties of, each amendment to any Global
Development Plan for the Development of Products applicable to the U.S.
Territory or the budget with respect thereto;  (c)           monitoring the
progress of the Development Program under each Global Development Plan for the
Development of Products applicable to the U.S. Territory and of each Partys
activities thereunder;    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   25


(d)           providing a forum
for consensual decision making with respect to the Development of Products
applicable to the U.S. Territory;  (e)           reviewing and
circulating to the Parties data, reports or other information submitted by
either Party with respect to work conducted under the Development Program;  (f)            overseeing the
conduct of Clinical Trials  for the
Development of Products applicable to the U.S. Territory, including without
limitation the conduct of the Ongoing Clinical Trial;  (g)           allocating
responsibility between the Parties for the Development of Products, including responsibility
for the conduct of Clinical Trials for [***], 
assigning activities and tasks and allocating FTEs between the Parties;  (h)           reviewing and [***]
any material agreement entered into by a Party with a Third Party pursuant to Section 8.2.1
related to Development (except for [***]) applicable to the U.S. Territory;  (i)            in conjunction with
the JCC, approving the overall strategy for publications and presentations in
support of Products in the U.S. Territory as determined by the Publication
Committee;  (j)            making such other
decisions as may be delegated to the JDC pursuant to this Agreement or by the
JSC or by mutual written agreement of the Parties during the Term;  (k)           establishing [***]
applicable to Development of the Products in the U.S. Territory as described in
Section 3.1.3(c);  (l)            in conjunction with
the JCC, reviewing and approving any proposals for [***] of existing
Co-Commercialized Products, including, without limitation, [***] and [***];  (m)          reconciling issues between the Parties
with respect to the Parties respective share of Development Costs with respect
to Products;  (n)           subject to Sections 12.4.1 and
12.5.2, reviewing adherence of the Development of Product applicable to the
U.S. Territory to GSK Internal Policies;  (o)           designing (i) the protocol for
the [***] Study, (ii) the protocols for the [***](s), and (iii) the
protocol for the [***];  (p)           establishing the [***] thereof;  (q)           discussing the program for [***]
conducted by SYNTA to [***] of STA-4783 as described in Section [***] and
reviewing the results thereof;    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   26


(r)            establishing any
sub-committees or teams as deemed necessary; and  (s)           resolving any other
disputes raised to the JDC.  2.2.5        Dispute Resolution.  The JDC members shall use reasonable efforts
to reach agreement on any and all matters.Inthe event that, despite such reasonable efforts, agreement on a
particular matter cannot be reached by the JDC within [***] days after the JDC
first meets to consider such matter, then the matter shall be referred to the
JSC for resolution pursuant to Section 2.1.5.  2.3           Joint
Commercialization Committee.  2.3.1Establishment;
Term.As soon as
practicable but in any event within [***] Business Days of the Effective Date,
SYNTA and GSK shall establish the JCC. The JCC shall have and perform the
responsibilities set forth in Section 2.3.4.  Unless otherwise agreed by the Parties, the
term for the JCC shall commence at such time as the JSC determines and continue
for so long as SYNTA Co-Commercialization Activities and GSK
Co-Commercialization Activities are being conducted with respect to a
Co-Commercialized Product under the terms of a Co-Commercialization Agreement.  2.3.2Membership.Each of SYNTA and GSK shall designate in
writing an equal number (not less than [***]) of representatives to the
JCC.For a one (1) year period beginning on the establishment of the
JCC, a SYNTA representative to the JSC shall serve as the chairperson of the
JCC.  For each subsequent one-year
period, representatives of the Parties shall alternate as the chairperson of
the JCC.  Each Party shall have the
right at any time to substitute individuals, on a permanent or temporary basis,
for any of its previously designated representatives to the JCC by giving
written notice to the other Party.  2.3.3        Meetings.  (a)           Schedule of
Meetings; Agenda.  The first meeting
of the JCC shall take place within [***] days after the establishment of the
JCC.  The JCC shall meet on a quarterly
basis, or more or less frequently as agreed, taking into account, without
limitation, the planning needs for the conduct of SYNTA Co-Commercialization
Activities and GSK Co-Commercialization Activities for Co-Commercialized
Products and the responsibilities of the JCC. 
Special meetings of the JCC may be convened by any member upon not less
than [***] days (or, if such meeting is proposed to be conducted by
teleconference, upon [***] days) written notice to the other members; provided,
that notice of any such special meeting may be waived at any time if mutually
agreed by the Parties.  Regular and
special meetings of the JCC may be held in person or by teleconference or
videoconference; provided, that, meetings held in person shall alternate
between the respective offices of the Parties in Lexington, Massachusetts and
Philadelphia, Pennsylvania or at other locations mutually agreeable to the JCC
members.  A designated secretary from the
opposing Party to the chairperson shall be responsible for preparing and
circulating to each JCC member an agenda for each JCC meeting not later than
[***] week prior to such meeting.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   27


(b)           Quorum; Voting;
Decisions.  At each JCC meeting, (i) the
presence in person of at least[***] designated by each
Party shall constitute a quorum and (ii) the representatives of a Party
shall have [***] on all matters before the JCC at such meeting.  All decisions of the JCC, shall be made by
[***] vote.  Alternatively, the JCC may
act by written consent signed by at least [***]designated by
each Party.  Whenever any action by the
JCC is called for hereunder during a time period in which the JCC is not
scheduled to meet, the chairperson shall cause the JCC to take the action in
the requested time period by calling a special meeting or by circulating a written
consent.  Representatives of each Party
or of its Affiliates who are not members of the JCC (including, without
limitation, members of the JPC, financial representatives and Alliance
Managers) may attend JCC meetings as non-voting observers upon advance written
notice.  In the event that the JCC is
unable to resolve any matter before it, such matter shall be resolved in
accordance with Section 2.3.5.  (c)           Minutes.  The designated secretary shall keep minutes
of all meetings that record all decisions and all actions recommended or taken
in reasonable detail.  Drafts of the
minutes shall be prepared and circulated to the members of the JCC within a
reasonable time after the meeting, not to exceed [***] Business Days.  Each member of the JCC shall have the
opportunity to provide comments on the draft minutes.  Final minutes of each meeting shall be
approved as the first order of business at the subsequent JCC meeting.  (d)           Expenses.  SYNTA and GSK shall each bear all expenses of
their respective JCC representatives related to their participation on the JCC
and attendance at JCC meetings and such expenses shall not be Development Costs
or Commercialization Expenses for purposes of this Agreement.  2.3.4        Responsibilities.  The JCC shall be responsible for overseeing
the conduct and progress of the SYNTA Co-Commercialization Activities and GSK
Co-Commercialization Activities for each Co-Commercialized Product in the
Co-Commercialization Territory.  Without
limiting the generality of the foregoing, the JCC shall have the following
responsibilities:  (a)           preparing, or
directing the preparation by the Parties of, each Product Co-Commercialization
Plan for Co-Commercialized Products in the Co-Commercialization Territory,
including the budgets with respect thereto;  (b)           preparing, or
directing the preparation by the Parties of, each amendment to any Product
Co-Commercialization Plan for Co-Commercialized Products in the
Co-Commercialization Territory or the related budget with respect thereto;  (c)           reviewing and approving
[***] matters for Co-Commercialized Products in the Co-Commercialization
Territory;  (d)           reviewing and
approving [***] matters for Co-Commercialized Products in the
Co-Commercialization Territory, including Co-Commercialization Trademarks;  (e)           reviewing and
approving [***] of Co-Commercialized Products in the Co-Commercialization
Territory, including [***];     Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.  28


(f)            reviewing and
approving [***], including [***] for Co-Commercialized Products in the
Co-Commercialization Territory;  (g)           determining the
appropriate use of [***] in support of the Co-Commercialized Products;  (h)           determining the
format and quantities of promotional sales, marketing and educational materials
for the Co-Commercialized Products;  (i)            in conjunction with
the JDC, reviewing and approving any proposals for [***] of existing
Co-Commercialized Products, including, without limitation, [***] after First
Commercial Sale and [***];  (j)            agreeing upon the
design and implementation of all Co-Commercialized Product [***] activities;  (k)           monitoring the
progress of Commercialization of Co-Commercialized Products in the
Co-Commercialization Territory under each Product Co-Commercialization Plan and
of each Partys activities thereunder;  (l)            reviewing and circulating
to the Parties data, reports or other information submitted by either Party
with respect to the Commercialization of Co-Commercialized Products in the
Co-Commercialization Territory;  (m)          reconciling issues
between the Parties with respect to the Parties respective share of Operating
Income (Loss) with respect to Co-Commercialized Products in the
Co-Commercialization Territory;  (n)           preparing or
directing the preparation by the Parties of short-term and long-term sales
forecasts for Co-Commercialized Products;  (o)           determining
appropriate targets for sales force staffing and territory mapping purposes,
determining the appropriate level for, and allocation of Promotional Efforts
to, each Party and coordinating the conduct of Promotional Efforts and sales
training of both Parties with respect to Co-Commercialized Products;  (p)           overseeing all
recalls, market withdrawals and any other corrective actions agreed to by the
Parties related to Co-Commercialized Products;  (q)           receiving and
providing to the Parties sales reports pertaining to Co-Commercialized
Products;  (r)            subject to Sections
12.4.1 and 12.5.2, monitoring compliance of marketing activities throughout the
U.S.  Territory with Applicable Laws and
GSK Internal Policies, and the corporate governance codes and policies of SYNTA
to the extent they do not conflict with GSK Internal Policies and Applicable
Laws;   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.  29


(s)           reviewing and
approving the Commercialization Transition Plan;  (t)            in conjunction with
the JDC, approving the overall strategy for [***] in support of Products in the
U.S. Territory as determined by the Publication Committee;  (u)           making such other
decisions as may be delegated to the JCC pursuant to this Agreement or by the
JSC or by mutual written agreement of the Parties during the Term;  (v)           establishing any subcommittees or teams as deemed
necessary; and  (w)          resolving any other disputes raised to the JCC.  2.3.5Dispute
Resolution.  The JCC
members shall use reasonable efforts to reach agreement on any and all
matters.Inthe event
that, despite such reasonable efforts, agreement on a particular matter cannot
be reached by the JCC within [***] days after the JCC first meets to consider
such matter, then the matter shall be referred to the JSC for resolution
pursuant to Section 2.1.5.  2.4           Alliance
Managers.Each Party
shall appoint, within [***] Business Days after the Effective Date, a person
who shall oversee interactions between the Parties for all matters related to
the Development and Commercialization of Products between meetings of the JSC,
the JDC, and the JCC (each, an Alliance Manager).  The Alliance Managers shall attend all
meetings of the JSC and shall have the right to attend all meetings of the JDC,
the JCC, and the JPC as the case may be, as non-voting participants at such
meetings.  Each Party may replace its
Alliance Manager at any time or may designate different Alliance Managers with
respect to Development and Commercialization, respectively, by notice in
writing to the other Party.  2.5           Joint
Patent Committee.  2.5.1Establishment;
Term.As soon as
practicable but in any event within [***] ([***]) Business Days after the
Effective Date, SYNTA and GSK shall establish the JPC. The JPC shall have and
perform the responsibilities set forth in Section 2.5.4.  Unless otherwise agreed by the Parties, the
term for the JPC shall commence at such time as the JSC determines and continue
for the Term.  2.5.2Membership.Each of SYNTA and GSK shall designate in
writing an equal number (not less than [***]) of representatives to the
JPC.For a one (1) year period beginning on the establishment of the
JPC, a SYNTA representative to the JSC shall serve as the chairperson of the
JPC.  For each subsequent one-year
period, representatives of the Parties shall alternate as the chairperson of
the JPC.  Each Party shall have the
right at any time to substitute individuals, on a permanent or temporary basis,
for any of its previously designated representatives to the JPC by giving
written notice to the other Party.  2.5.3        Meetings.  (a)           Schedule of
Meetings; Agenda.  The JPC shall meet
as needed, taking into account, without limitation, the planning needs for
protecting Patent Rights and   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   30


Technology
and the responsibilities of the JPC. 
Special meetings of the JPC may be convened by any member upon not less
than [***] days (or, if such meeting is proposed to be conducted by
teleconference, upon [***] days) written notice to the other members; provided,
that notice of any such special meeting may be waived at any time, if mutually
agreed by the Parties.  Regular and
special meetings of the JPC may be held in person or by teleconference or
videoconference; provided, that, meetings held in person shall alternate
between the respective offices of the Parties in Lexington, Massachusetts and
Philadelphia, Pennsylvania or at other locations mutually agreeable to the JPC
members.  The chairperson shall be responsible
for preparing and circulating to each JPC member an agenda for each JPC meeting
not later than one (1) week prior to such meeting.  (b)           Quorum; Voting;
Decisions.  At each JPC meeting, (i) the
presence in person of at least[***] designated by each
Party shall constitute a quorum and (ii) the representatives of a Party
shall have [***] on all matters before the JPC at such meeting.  All decisions of the JPC, shall be made by
[***] vote.  Alternatively, the JPC may
act by written consent signed by at least [***]designated by
each Party.  Whenever any action by the
JPC is called for hereunder during a time period in which the JPC is not
scheduled to meet, the chairperson shall cause the JPC to take the action in
the requested time period by calling a special meeting or by circulating a written
consent.  Representatives of each Party
or of its Affiliates who are not members of the JPC (including, without
limitation, the Alliance Managers) may attend JPC meetings as non-voting
observers.  In the event that the JPC is
unable to resolve any matter before it, such matter shall be resolved in
accordance with Section 2.5.5.  (c)           Minutes.  If the JPC deems it necessary to take minutes
at the meeting of the JPC, then the chairperson shall designate a secretary at
each meeting of the JPC and such designated secretary shall keep minutes of its
meetings that record all decisions and all actions recommended or taken in
reasonable detail.  Drafts of the minutes
shall be prepared and circulated to the members of the JPC within a reasonable
time after the meeting, not to exceed [***] Business Days.  Each member of the JPC shall have the
opportunity to provide comments on the draft minutes.  Final minutes of each meeting, if taken at such
meeting, shall be approved as the first order of business at the subsequent JPC
meeting.  (d)           Expenses.  SYNTA and GSK shall each bear all expenses of
their respective JPC representatives related to their participation on the JPC
and attendance at JPC meetings and such expenses shall not be Development Costs
and Commercialization Expenses for purposes of this Agreement.  2.5.4        Responsibilities.  Subject to Article 10, the JPC shall be
responsible for developing a strategy to
protect Program Technology and to develop and coordinate strategy with respect
to theif,filing, maintenance, prosecution,
enforcement and defense of SYNTA Patent Rights, Joint Patent Rights and GSK
Patent Rights.  2.5.5Dispute Resolution.  The JPC members shall use reasonable efforts
to reach agreement on any and all matters.Inthe event that, despite such
reasonable efforts, agreement on a particular matter cannot be reached by the
JPC within [***] days after the JPC first meets to consider such matter, then
the matter shall be decided by the Party who has responsibility for such matter
in accordance with Articles 9 and 10 of this Agreement.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.  31


Notwithstanding the
foregoing, disputes related to (a) the [***] of the Class 1 and Class 2
Patents, or (b) the enforcement and defense of (i) the SYNTA Patent
Rights derived from the [***] from which the [***] were derived, (ii) any
of the [***] with respect to the Products and (iii) [***] shall be [***]
selected by the JPC and, unless otherwise agreed by the Parties, [***] was not
at any time during the past [***] prior to such dispute, [***] for either of
the Parties, and if such [***] for either Party in the previous [***] years,
such Party will inform the other of the nature of such [***].  Any final decision regarding (a) above
will be a [***] based upon such [***], and any final decision regarding (b) above
will be a [***] based upon such [***].  2.6           Interests
of the Parties, Limitations of Powers.  All decisions made and all actions taken by
the JSC, the JDC, the JCC, the JPC, the Publication Committee or the officersofthe Parties
pursuant to Section 2.1.5 shall be made or taken with due interest of both
Parties considered in good faith.  The
JSC, the JDC, the JCC, the JPC, the Publication Committee, the Alliance
Managers and any other committees established pursuant to this Agreement or as
determined by the foregoing committees, will have only such powers as are
specifically delegated to it in this Agreement, and will have no power to amend
this Agreement or waive a Partys rights or obligations under this Agreement.  2.7           Appointment
Not an Obligation; No Breach. 
The appointment of members of the JSC, JDC, JCC, the JPC, the
Publication Committee and Alliance Managers is a right of each Party and not an
obligation and shall not be a deliverable as defined in EITF Issue No. 00-21.  Each Party shall be free to determine not to
appoint members to the JSC, JDC, JCC, JPC, Publication Committee and not to
appoint an Alliance Manager.  If a Party
(the non-Appointing Party) does not appoint members of the JSC, JDC, JCC,
JPC, Publication Committee or an Alliance Manager, it shall not be a breach of
this Agreement, nor shall any consideration be required to be returned, and the
other Party (the Appointing Party) shall have the votes and the
decision-making power of the non-Appointing Party unless and until such members
are appointed by the non-Appointing Party.  3.             DEVELOPMENT OF PRODUCTS  3.1           Implementation of Development Program.  3.1.1        Objectives of the Development Program.  The objectives of the Development Program
shall be the Development of Products in order to obtain Commercialization
Regulatory Approval of Products in the Territory pursuant to the Global
Development Plan.  3.1.2        Preparation of Global Development Plan.A high level initial Global Development
Plan for the period commencing on the Effective Date and continuing until [***]
has been prepared and agreed upon by the Parties and shall be developed further
by the JDC after the Effective Date.  In
addition to the Ongoing Clinical Trial and certain other studies to be
conducted by SYNTA, the initial Global Development Plan may also include
material studies to be performed by GSK for the ROW Territory.  The inclusion of these studies shall be for
informational and planning purposes only to permit the JDC to assist in global
Development, but the design and conduct of such studies shall not be subject to
JDC approval.  On [***] basis, or    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   32


more frequently as agreed by the Parties, the JDC shall
review and update the Global Development Plan with respect to Development of
any Products applicable to the U.S. Territory. 
The JDC may make amendments to the Global Development Plan as it applies
to Development in the U.S. Territory as necessary for the day-to-day management
of such Development, taking into consideration technical, scientific and
commercial factors that may affect the course of Development; provided, that
any such amendments will be materially aligned with the goals of the initial
Global Development Plan unless mutually agreed by the Parties.During the Term, the Parties
may agree to conduct further Development of the Products not covered in the
initial Global Development Plan as more fully described below in Section 3.1.3(b)-(c),
and in such case, the Parties will prepare additional Global Development Plans
for such Development at the direction of the JDC and submit such Global
Development Plans to the JDC for approval (with respect to Development in the
U.S. Territory) as provided in Section 2.2.4(a) at least [***] days
before the meeting at which it will be considered; provided, thatthe Parties shall manage the preparation
of each such Global Development Plan in a manner designed to accommodate the
Parties internal annual planning cycles, and shall obtain JDC approval no later
than [***] 30 of each Calendar Year unless otherwise agreed by the
Parties.  Each Global Development Plan
shall: (a) set forth (i) the Development objectives, including
pre-clinical studies, Clinical Trials and other activities, priorities,
timelines, budget and resources for the Calendar Years covered by such Global
Development Plan with reasonable specificity, (ii) which activities are
SYNTA Development Activities and/or GSK Development Activities and (iii) with
respect to such Development Activities, the number of FTEs to be allocated to
perform such activities and the corresponding FTE Cost; and (b) be
consistent with the other terms of this Agreement and it is the expectation of
the Parties that all Development in the Co-Commercialization Territory shall be
a joint responsibility of the Parties and that SYNTA shall conduct a portion of
the Development activities under the Global Development Plan.  3.1.3        Responsibility for Development of Products.  (a)           Global
Development Plans.  SYNTA shall be
responsible for the conduct of the SYNTA Development Activities set forth in
the Global Development Plans, which, with respect to the initial Global
Development Plan includes the conduct of the Ongoing Clinical Trial and all
Development to be undertaken pursuant to Section 3.1.3(b).  GSK shall be responsible for the conduct of
the GSK Development Activities set forth in the Global Development Plans which
shall include the Development of Products for all Indications in the ROW
Territory.  The JDC shall allocate activities
to each Party for the Development of Products for each New Indication in the
U.S. Territory (with the understanding that Development for the U.S. Territory
may include conducting some activities in countries outside of the U.S.
Territory, which activities shall be considered to be Development related to
the U.S. Territory), except as may be covered in the initial Global Development
Plan.  Each Party shall have the right to
engage Third Party contractors to perform some of its Development Activities in
connection with the Development of Products hereunder, subject to the execution
by each such Third Party contractor of an agreement containing provisions with
respect to confidentiality and assignment of Technology that are consistent
with, and comparable in scope to, Articles 9 and 10 of this Agreement.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   33


(b)           Additional SYNTA
Development Work Prior to [***] 
Prior to the [***] of the [***], SYNTA shallcommence the conduct of the following, as more fully
described below: (A) one Phase 1 Clinical Trial designed to [***] STA-4783
(the [***] Study), (B) one (1) [***], and at SYNTAs sole election
one (1) or more additional [***]), (C) one (1) [***], which the
Parties have agreed shall be [***], and (D) [***] undertaken to [***] of
STA-4783.  SYNTA shall be solely
responsible for all [***] associated with the conduct of the foregoing
activities until completion of such activities. 
New Indication shall mean an Indication other than metastatic
melanoma.  (i)            SYNTAshallprovide the JDC with written notice
specifying a proposal for the conduct of each of the [***] Study and the [***]If the JDC approves such proposals,
then the JDC shall design the protocols for the [***] Study and the [***](s),
and shall establish the criteria that must be achieved in each [***] to
progress Development of the Product into [***]).  Upon achievement of the [***] in a [***] with
respect to a particular Product, progression of all further Development of such
Product in a [***] shall be determined by the JDC.  The Parties shall be responsible for
Development Costs associated with Development in such [***] in accordance with Section 3.6.1.  For clarity, the [***] referenced in the
foregoing sentence is not the [***] described in Section 3.1.3(b)(ii).  Notwithstanding the foregoing, the decision
of the JDC to progress Development of a Product upon achievement of the [***]
may be deferred, [***], until [***]  (ii)           SYNTAshallprovide the JDC with written notice
specifying a proposal for the conduct of the [***]. If the JDCapproves such proposal, then the JDC shall design the protocol for the
[***] and shall establish criteria that must be achieved in such [***] to
progress Development of the Product into [***] 
Upon achievement of the [***] in such New [***] with respect to a
particular Product in a New Indication, progression of Development in a [***]
in such New Indication shall be determined by the JDC.  The Parties shall be responsible for
Development Costs associated with Development in such Phase 3 Clinical Trial in
accordance with Section 3.6.1. 
Notwithstanding the foregoing, the decision of the JDC to progress
Development of a Product upon achievement of the [***] may be deferred, [***],
until [***].  (iii)          SYNTA shall be responsible for the [***]
STA-4783.  (c)Additional
Development Work After [***]either Partymayidentify New
Indications that it wishes to pursue with respect to Development of Products,
and shall provide the JDC withwritten notice specifying
such New Indication and a proposal and budget for the Development of the
Product in the New Indication through Proof of Concept.  If the JDCapproves
such Development, then the JDC shall design the protocol for the Proof of
Concept Clinical Trial, and shall establish Proof of Concept Criteria that must
be achieved in such Proof of Concept Clinical Trial to progress Development of
the Product into a Phase 3 Clinical Trial. 
Upon achievement of the Proof of Concept Criteria in such Proof of
Concept Clinical Trial in such New Indication, progression of Development in a
Phase 3 Clinical Trial in such New Indication shall be determined by the
JDC.  The Parties shall be responsible
for Development Costs associated with Development in such New Indication through
Completion of the applicable Proof of Concept Clinical Trial and any further
Phase 3 Clinical Trials if SYNTA    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   34


does not
exercise its Development Opt-Out Right with respect to such Phase 3 Clinical
Trials, in accordance with Section 3.6.1. 
For the avoidance of doubt, if there is not a Unanimous Decision to
conduct Development under this Section 3.1.3(c), then [***] shall have the
final say on whether or not to conduct such Development and may either prohibit
further Development in a New Indication or conduct Development in a New
Indication under this Section 3.1.3(c) without SYNTAs participation,
and in the latter case, the provisions of Section 3.1.3(d) shall
apply.  (d)           SYNTA Opt-Out of Development on
New Indication-by-New Indication Basis. 
With respect to any New Indication under Development, SYNTA shall have
the right (the Development Opt-Out Right), on a New Indication-by-New
Indication basis, to opt not to participate in such Development commencing with
the applicable [***] for such New Indication. 
SYNTA shall exercise its Development Opt-Out Right upon written notice
to GSK (the Development Opt-Out Notice) which shall be delivered to GSK no
later than [***] days after the final proposal and budget prepared by the JDC
for such Phase 3 Clinical Trial in a particular New Indication is delivered to
SYNTA (which shall be at least [***] days prior to the proposed date of
Initiation of such [***]), and such Development Opt-Out Right shall become
effective immediately upon receipt of the Development Opt-Out Notice by
GSK.  If SYNTA exercises its Development
Opt-Out Right for a New Indication (each, an Opt-Out Indication), then from
and after the effective date of the Development Opt-Out Right (i) SYNTA
shall have no further right to conduct any Development of any Product in the
Opt-Out Indication anywhere in the Territory (unless GSK permits otherwise in
its sole discretion or unless such Development relates to the [***] Study, the
[***] described in Section 3.1.3(b)), and GSK shall be solely responsible
for any such Development in its sole discretion, (ii) SYNTA shall have no
further right to conduct any SYNTA Co-Commercialization Activities for any
Product in the Opt-Out Indication anywhere in the Territory (unless GSK permits
otherwise in its sole discretion), (iii) GSK shall have all
decision-making authority for all Development and Commercialization matters in
the Opt-Out Indication, including matters that would otherwise be SYNTA
Decisions or Unanimous Decisions for all Products in the Opt-Out Indication,
including those Products for which SYNTA participated in Development and bore
its share of Development Costs as set forth in Section 3.6.1 related
thereto, (iv) all decisions related to the Commercialization matters set
forth in Sections 2.3.4(a)-(d) for all Products in all Indications shall
be GSK Decisions, and any SYNTA Decisions with respect to Development of
Products in all Indications shall become Unanimous Decisions, (v) with
respect to Products in Indications for which SYNTA participated in Development
in a [***] and bore its share of Development Costs as set forth in Section 3.6.1
related thereto, SYNTA shall have no further right to conduct SYNTA
Co-Commercialization Activities except that SYNTA may continue to detail such
Products to group purchasing organizations, the Veterans
Administration/Department of Defense, hospitals and oncology clinics as
otherwise provided in this Agreement and any additional activities as GSK may
decide [***], it being acknowledged that the Parties will work in good faith to
reasonably allocate activities between the Parties to minimize the impact on
the Product;(vi) the JDC and
JCC shall be terminated unless SYNTA is conducting the SYNTA
Co-Commercialization Activities described in Section 3.1.3(d)(v) with
respect to an Indication other than the Opt-Out Indication or is conducting
Development of Products in an Indication other than the Opt-Out Indication, (vii) GSK
shall keep the JSC periodically informed of Development and Commercialization
of Products in the Territory in the Opt-Out Indication if the JDC or JCC is
terminated, (viii) GSK shall be entitled to recoup the Development Costs
that SYNTA would otherwise have borne   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   35


pursuant to Section 3.6.1(b) for
Development of Products in the Opt-Out Indication by adjusting the milestones
payable under Section 6.4.1(a) as set forth below, so long as such
milestones have not been paid previously (and, if all such Development Costs
are not recovered by the following adjustments to milestone payments, or where
all milestones have been paid previously, GSK shall be entitled to deduct the
remaining amount from Operating Income (Loss) or royalties otherwise payable
under this Agreement, by retaining up to [***] percent ([***]%) of Operating
Income (Loss) or royalties due to SYNTA on a [***] basis): (A) GSKs
obligation to pay milestones for both [***] for any Product for the Opt-Out
Indication and [***] for any Product for the Opt-Out Indication shall be
reduced by [***] percent ([***]%), (B) GSKs obligation to pay any
milestone for [***] for any Product for the Opt-Out Indication shall be reduced
by [***] percent ([***]%), and(ix) with
respect to all Products under Development in or being Commercialized for the
Opt-Out Indication: (A) the SYNTA Development Cost-Sharing Percentage
shall be [***] percent ([***]%), (B) the GSK Development Cost-Sharing
Percentage shall be [***] percent ([***]%) and (C) if SYNTA has not borne
the SYNTA Development Cost Sharing Percentage for at least [***] of the
aggregate Development Costs for all New Indications and metastatic melanoma
under Development in [***] (or that are being Commercialized), then the GSK
Operating Income (Loss) Percentage shall be [***] percent ([***]%) and the
SYNTA Operating Income (Loss) Sharing Percentage shall be [***] percent
([***]%) (and shall not be subject to further adjustment pursuant to Section 1.56)except that, as additional New Indications
enter [***], if SYNTA bears the SYNTA Development Cost Sharing Percentage for
more than [***] of the aggregate Development Costs for all New Indications and
metastatic melanoma under Development in [***] (or that are being
Commercialized), then the GSK Operating Income (Loss) Percentage shall be
calculated in accordance with Section 1.56 and the SYNTA Operating Income
(Loss) Sharing Percentage shall be calculated in accordance with Section 1.122.  For the avoidance of doubt, the determination
of the GSK Operating Income (Loss) Sharing Percentage and SYNTA Operating
Income (Loss) Sharing Percentage as set forth in Section 3.1.3(d)(ix)(C) is
intended to adjust from [***] to [***] depending upon SYNTAs share of
aggregate Development Costs at such time.  (e)           Metastatic Melanoma Development
Opt-Out.  If, after Completion of the
Ongoing Clinical Trial, the JDC (or GSK) wishes to conduct further Development
in the Indication of metastatic melanoma, then any further Development will not
be considered to be Development in a New Indication.  Notwithstanding the foregoing, SYNTA may
exercise its Development Opt-Out Right described in Section 3.1.3(d) with
respect to any additional Development in metastatic melanoma, and the
provisions of Section 3.1.3(d) shall apply, except that SYNTA shall
continue to have the right to conduct SYNTA Co-Commercialization Activities for
the Product in the Indication of metastatic melanoma that was Developed and/or
launched in such Indication prior to SYNTAs exercise of the Development
Opt-Out Right as set forth in this Section 3.1.3(e).  3.2           Development
Diligence and Compliance. 
Each Party shall (a) use Commercially Reasonable Efforts during the
Term to Develop Products, (b) conduct its Development Activities with
respect to the Products as set forth in the Global Development Plansand (c) commit such resources (including
employees, consultants, contractors, facilities, equipment and materials) as it
deems necessary to conduct such Development Activities.  Each Party shall perform its obligations
under each Global Development Plan in good scientific    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   36


manner and in compliance in
all material respects with all Applicable Laws and with all applicable GSK
Internal Policies.  For purposes of
clarity, with respect to each activity performed under a Global Development Plan
that will or would reasonably be expected to be submitted to a Regulatory
Authority in support of a Regulatory Filing or Drug Approval Application, the
Party performing such activity shall comply in all material respects with GLPs,
GMPs or Good Clinical Practices (or, if and as appropriate under the
circumstances, International Conference on Harmonization (ICH) guidance or
other comparable regulation and guidance of any Regulatory Authority in any
country or region in the Territory).  3.3           Development
Program Reports.  The Parties
shall keep the JDC regularly informed of the progress of its efforts to Develop
Products in the U.S. Territory and GSK shall keep the JSC regularly informed of
the progress of its efforts to Develop Products in the ROW Territory.  Without limiting the generality of the
foregoing, each Party shall, on at least a [***] basis, provide the JDC with
reports in reasonable detail regarding the status of all material [***] studies
and activities (including [***] and [***] studies), [***] and other activities
conducted under the Development Program in the U.S. Territory, together with
all [***] and results generated in each such [***] study, activity and/or [***]
and such additional information that it has in its possession as may be
reasonably requested from time to time by the JDC.  3.4Right of Access; Cooperation.Each Party shall cooperate in the performance
of the Development Program, and, subject to the terms of this Agreement and any
confidentiality obligations to Third Parties, promptly provide the other Party
(at such Partys reasonable request) with access to all Technology, material
and relevant data, results and information produced in connection with the
conduct of such Partys Development Activities as set forth in the applicable
Development Plan in its original format, without translation where possible, as
necessary to perform its obligations and exercise of its rights under this
Agreement, free of charge.  The Parties
shall permit each other to have the right to
[***] Regulatory Filings, Drug Approval Applications, Regulatory Approvals and
Commercialization Regulatory Approvals for the purpose of obtaining
Commercialization Regulatory Approvals for the Product in the Territory.The scope, timing and procedure for transfer of all other
tangible embodiments of Program Technology reasonably necessary or useful for
the Parties to perform their obligations hereunder or to Develop and
Commercialize any Product, which is not existing on the Effective Date, shall
be further defined by the Parties from time to time, as needed.  3.5           Supply
of Proprietary Materials; Technology Transfer.  3.5.1        Proprietary
Materials.  From time to
time during the Term, either Party (the Transferring Party) may supply the
other Party (the Recipient Party) with proprietary materials of the
Transferring Party for use in the Development Program.  In connection therewith, each Recipient Party
hereby agrees that (a) it shall not use such proprietary materials for any
purpose other than exercising its rights or performing its obligations
hereunder and in accordance with the Development Plan; (b) it shall use
such proprietary materials only in compliance with all Applicable Laws; (c) it
shall not transfer any such proprietary materials to any Third Party without
the prior written consent of the Transferring Party, except for (i) the
transfer of Products for use in Clinical Trials or (ii) in a Permitted
Transaction or as otherwise expressly permitted hereby; (d) the Recipient
Party shall not acquire any right, title or interest in   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   37


or to such proprietary
materials as a result of such supply by the Transferring Party; and (e) upon
the expiration or termination of the Development Program, the Recipient Party
shall, if and as instructed by the Transferring Party, either destroy or return
any such proprietary materials that are not the subject of the grant of a
continuing license hereunder.  3.5.2        Technology
Transfer.  Promptly after
the Effective Date, SYNTA shall effect a Technology Transfer to GSK in such a
manner to enable GSK to manage and conduct all activities related to (a) commercial
supply of API and Product after the Effective Date, and (b) clinical
supply of API and Product after Commercialization Regulatory Approval is
obtained by SYNTA for the Product in the metastatic melanoma Indication.  To the extent necessary, the Parties will
enter into appropriate clinical trial supply agreements for supply of API for
Development of the Product.  3.6           Development
Cost-Sharing; Reconciliation.  3.6.1Development Cost-Sharing.The
Parties agree to cooperate to identify and implement opportunities that could
reasonably improve the value of the Collaboration for both Parties, including
opportunities to reduce the costs through the use of GSKs preferred supply
arrangements and GSKs procurement expertise.  (a)           SYNTA
Responsibility.  SYNTA shall be [***]
responsible for funding [***] percent ([***]%) of all Development Costs
associated with the [***], the [***] Study, the one or more New [***] and the
[***] described in Section 3.1.3(b).  (b)Shared Costs.  For all other Development for which SYNTA has
not exercised its Development Opt-Out Right,(i) SYNTA shall be
responsible for funding the SYNTA Development Cost-Sharing Percentage of all
Development Costs applicable thereto and (ii) GSK shall be responsible for
funding the GSK Cost-Sharing Percentage of all Development Costs applicable
thereto.  3.6.2        Reconciliation
of Development Costs.  (a)Reports;
Reconciliation Payments.  With
respect to Development Costs incurred by the Parties in accordance with Section 3.6.1(b),
within [***] days following the end of each [***] during the Term, each of
SYNTA and GSK shall submit to the JDC a written report setting forth in
reasonable detail all Development Costs incurred by each such Party over such
[***] applicable to the conduct of the Development Program.Within [***] days following
the receipt by the JDC of such written reports, the JDC shall prepare and
submit to each Party a written report setting forth in reasonable detail (i) the
calculation of all such Development Costs incurred by both Parties over such
[***] and any deviations from the applicable budget and (ii) the
calculation of the net amount owed by GSK to SYNTA or by SYNTA to GSK in order
to ensure the appropriate sharing of such Development Costs in accordance with Section 3.6.1(b).The
Party that is due for reimbursement of Development Costs in the preceding [***]
shall invoice the other Party.  Such
payments by one Party to reimburse the other Partys expenditures for
Development Costs for the purposes of cost sharing under this Agreement shall
be paid within [***] Business Days following receipt of the invoice.    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   38


In the event that the Parties disagree with the reported costs and any
over/underspend, approval shall be required by the JSC following receipt of the
report by the JSC.  A decision by the JSC
shall be required within [***] Business Days following receipt of the reports.  Where the JSC does not so agree with the
reported costs or over/underspend, any such unapproved spend shall be borne
solely by the Party incurring them. If the total budget for the Ongoing
Clinical Trial as set out in the initial Global Development Plan is exceeded,
then such overage shall be allocated in accordance with Sections 1.54 and
1.121.  If GSK incurs any Development
Costs associated with the Ongoing Clinical Trial, then any payments due to GSK
by SYNTA shall be paid after Completion of the Ongoing Clinical Trial and
within [***] Business Days after receipt of an invoice therefor.  (b)           Records; Audit Rights.  Each Party shall keep and maintain for [***]
years complete and accurate records of all Development Costs incurred in the
Development of Products in sufficient detail to allow confirmation of same by
an independent certified public accountant. 
Each Party (the Cost Auditing Party) shall have the right for a period
of [***] after such Development Costs are incurred, to appoint at its expense
an independent certified public accountant reasonably acceptable to the other
Party (the Cost Audited Party) to audit the relevant records of the Cost
Audited Party or its Affiliates to verify that the amount of Development Costs
incurred have been correctly determined. 
The Cost Audited Party or its Affiliates shall each make its records
available for audit by the independent certified public accountant during
regular business hours at such place or places where such records are
customarily kept, upon [***] days written notice from the Cost Auditing
Party.  Such audit right shall not be
exercised by a Cost Auditing Party more than [***] in any Calendar Year and no
twelve (12) month period may be audited more than [***].  The independent certified public accountant
will only disclose the results (any sums either over/under paid) of such audit
to the Cost Auditing Party and no other details.  In the event there was an error in the amount
of such Development Costs reported by the Cost Audited Party hereunder, (a) if
the effect of the error resulted in an underpayment, the Cost Audited Party
shall promptly, on receipt of an invoice, make payment to the Cost Auditing
Party of the underpayment amount and (b) if the effect of the error
resulted in an overpayment, the Cost Auditing Party shall promptly on receipt
of an invoice make payment to the Cost Audited Party of the overpayment
amount.  The Cost Auditing Party shall
bear the full cost of such audit unless such audit discloses an error by the
Cost Audited Party of at least [***] percent ([***]%) of the aggregate amount
of the Development Costs in any Calendar Year subject to such audit, in which
case the Cost Audited Party shall reimburse the Cost Auditing Party for all
costs incurred by the Cost Auditing Party in connection with such audit.  4.             REGULATORY  4.1           Responsibility
for Regulatory Filings. 
SYNTA shall be responsible for preparing and filing Regulatory Filings
and Drug Approval Applications for the Product in the U.S. Territory for
metastatic melanoma in its own name and shall initially own Regulatory
Approvals and Commercialization Regulatory Approvals issuing therefrom, and GSK
shall be responsible for preparing and filing all Regulatory Filings and Drug
Approval Applications for Products in the ROW Territory in its own name and
shall be the owner of all Regulatory Approvals and Commercialization Regulatory
Approvals issuing therefrom.  As soon as
possible    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   39


after the Effective Date,
the Parties shall prepare and submit to the JSC for its approval a transition
plan (the Regulatory Filings Transfer Plan) pursuant to which SYNTA will
transfer to GSK ownership of (a) all Regulatory Filings, Drug Approval
Applications, Regulatory Approvals and Commercialization Regulatory Approvals
owned by SYNTA on the Effective Date that are applicable to Products in the ROW
Territory or applicable to the conduct of the Ongoing Clinical Trial at sites
in the ROW Territory, as soon as possible and (b) all Regulatory Approvals
and Commercialization Regulatory Approvals applicable to the Product in the
U.S. Territory issued to SYNTA during the Term, as soon as possible after
issuance thereof.  For clarity, transfer
of ownership from SYNTA to GSK of Regulatory Filings and Drug Approval Applications
in the U.S. Territory for the Product for metastatic melanoma shall not occur
prior to receipt of Regulatory Approval for metastatic melanoma in the U.S.
Territory.  If deemed necessary by GSK
that a separate IND should be opened, GSK shall be allowed to open such IND
with right of reference to the original IND application held by SYNTA.  Upon receipt of the first Commercialization
Regulatory Approval, the JSC shall have the responsibility of deciding if and
when the original IND is transferred from SYNTA to GSK.  The Parties acknowledge that SYNTA will be
conducting Development of the Product in the ROW Territory to support U.S.
registration of the Product under certain circumstances, and as a result, SYNTA
shall work with GSK to ensure a consistent global regulatory strategy.  4.2           Review
and Preparation of Regulatory Filings; Regulatory Meetings Prior to Completion
of Regulatory Filings Transfer Plan.  4.2.1        GSK
Review of SYNTA Filings. 
SYNTA shall use reasonable efforts to provide GSK with at least [***]
days advance notice (or, if [***] days is not possible, then the maximum
amount of notice possible) of any meeting with the FDA or EMEA or other
Regulatory Authority in the U.S. Territory or the European Union regarding a
Drug Approval Application relating to, or Regulatory Approval or
Commercialization Regulatory Approval for, the Product for which it is
responsible prior to transfer to GSK in accordance with the Regulatory Filings
Transfer Plan and GSK may provide advice to SYNTA with respect to such meeting
and elect to send one person to participate as an observer (at GSKs sole cost
and expense) in such meeting.  In
addition, subject to any Third Party confidentiality obligations, SYNTA shall (a) provide
GSK with drafts of each material Regulatory Filing or other material document
including 15 day alert reports and material correspondence pertaining to a
Product and prepared for submission to the FDA or other Regulatory Authority
sufficiently in advance of submission so that GSK may review and comment on the
substance of such Regulatory Filing or other document or correspondence in
accordance with the mutually agreed timeframe;
provided that if GSK does not respond within such timeframe to a 15 day alert
report SYNTA shall be free to submit such report;and (b) promptly
provide GSK with copies of any document or other correspondence received from
the FDA or other Regulatory Authority pertaining to any Product.  SYNTA shall also provide cover letters of
routine Regulatory Filings and GSK may request to receive copies of attachments
to such Regulatory Filings.  SYNTA shall
consider all comments of GSK in good faith, taking into account the best
interests of the Development and/or Commercialization of the Product on a
global basis.  4.2.2        SYNTA
Review of GSK Filings. 
GSK shall use reasonable efforts to provide SYNTA with at least [***]
days advance notice (or, if [***] days is not possible, then   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   40


the maximum amount of notice
possible) of any meeting with the FDA or other Regulatory Authority in the U.S.
Territory regarding a Drug Approval Application relating to, or Regulatory
Approval or Commercialization Regulatory Approval for, the Product for which it
is responsible and/or any meeting with any Regulatory Authority in the ROW
Territory with which SYNTA has filed a Regulatory Filing for the Product until
such Regulatory Filing is transferred to GSK pursuant to Section 4.1 and
SYNTA may provide advice to GSK with respect to such meeting and elect to send
one person to participate as an observer (at SYNTAs sole cost and expense) in
such meeting.  Without limiting the
foregoing, subject to any Third Party confidentiality obligations, GSK shall (a) provide
SYNTA with drafts of each Regulatory Filing or other material document and
material correspondence pertaining to a Product and prepared for submission to
the FDA or other Regulatory Authority in the ROW Territory sufficiently in
advance of submission so that SYNTA may review and comment on the substance of
such Regulatory Filing or other document or correspondence in accordance with
the mutually agreed timeframe and (b) promptly provide SYNTA with copies
of any document or other correspondence received from the FDA or other
Regulatory Authority in the ROW Territory pertaining to any Product.  GSK shall also provide cover letters of
routine Regulatory Filings and SYNTA may request to receive copies of
attachments to such Regulatory Filings. 
GSK shall consider all comments of SYNTA in good faith, taking into
account the best interests of the Development and/or Commercialization of the
Product on a global basis.  4.3           Review
and Preparation of Regulatory Filings; Regulatory Meetings After Completion of
Regulatory Filings Transfer Plan.  GSK shall keep SYNTA reasonably and regularly
informed of the status of the preparation of all material Regulatory Filings or
Drug Approval Applications or other document or correspondence pertaining to a
Product and prepared for submission to Regulatory Authorities in the ROW
Territory, and the issuance of Regulatory Approvals and Commercialization
Regulatory Approvals obtained by GSK for Products in the ROW Territory.  GSK shall consider all comments of SYNTA in
good faith, taking into account the best interests of the Development and/or
Commercialization of the Product on a global basis.  5.             COMMERCIALIZATION OF PRODUCT  5.1           Responsibility
for Commercialization of Products.  5.1.1        Co-Commercialization Territory;
Co-Commercialization Agreement; Opt-Out Right.  (a)           SYNTA and GSK shall be responsible
for conduct of the SYNTA Co-Commercialization Activities and the GSK
Co-Commercialization Activities, respectively, for the Co-Commercialized
Product in the Co-Commercialization Territory, subject to SYNTAs right to
opt-out of Commercialization in the Co-Commercialization Territory as described
below.  It is anticipated that, with
respect to the Co-Commercialization Territory with respect to Co-Commercialized
Products approved in the metastatic melanoma Indication (i) SYNTA shall
conduct the SYNTA Co-Commercialization Activities, (ii) GSK shall conduct
the GSK Co-Commercialization Activities and shall book all sales of
Co-Commercialized Product, (iii) the Parties shall discuss in good faith
the allocation of Commercialization Activities for Indications   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   41


other than metastatic
melanoma with respect to Co-Commercialized Products, and (iv) all such
Commercialization Activities shall be performed in accordance with the Product
Co-Commercialization Plan and the Co-Commercialization Agreement (as defined below),
under the direction of the JCC.  (b)           Within [***] days of the expiration
of the Commercialization Opt-Out Date, theParties shall(i) commence the preparation of a
co-commercialization agreement (the Co-Commercialization Agreement) which
shall (A) set forth the terms applicable to the conduct of the SYNTA
Co-Commercialization Activities and the GSK Co-Commercialization Activities for
such Product in the Co-Commercialization Territory; (B) conform in all
material respects with the terms and conditions set forth in Schedule 6
attached; and (C) include such additional provisions as are usual and
customary for inclusion in a co-commercialization agreement between companies
in the pharmaceutical and biotechnology industries of comparable sizes to the
respective Parties; and (ii) negotiate and execute the
Co-Commercialization Agreement within [***] days (the Negotiation Period).  For purposes of clarity, any additional terms
negotiated by the Parties for inclusion in the Co-Commercialization Agreement
shall supplement and shall not materially expand, limit or change the terms set
forth on Schedule 6.  If the
Parties fail to execute and deliver the Co-Commercialization Agreement within
the Negotiation Period, the Parties shall use reasonable efforts to complete
such negotiations and to execute and deliver the Co-Commercialization Agreement
as soon as possible and shall each produce a list of issues on which they have
failed to reach agreement and submit its list to the JSC to be resolved in
accordance with Section 2.1.5.  (c)SYNTA may opt to not engage in the SYNTA Co-Commercialization Activities
as described above with GSK (the Commercialization Opt-Out Right) by
delivering written notice to GSK, on a Collaboration Compound-by-Collaboration
Compound basis, at any time on or before [***] (the Commercialization Opt-Out
Date).  If SYNTA exercises its
Commercialization Opt-Out Right with respect to a Collaboration Compound, then
the provisions of Section 5.2 will apply to all Products containing such
Collaboration Compound.  Notwithstanding
the foregoing, SYNTAs Commercialization Opt-Out Right may be exercised with
respect to an [***] of a Product (or alternatively, an [***] of a Product)
containing STA-4783 without also exercising the Commercialization Opt-Out Right
for an [***] of a Product (or alternatively, an [***] of a Product) containing
STA-4783, and may exercise its Commercialization Opt-Out Right for both [***]
of a Product containing STA-4783.  5.1.2        Royalty-Bearing Territory. GSK
shall have the sole right and responsibility for (a) all aspects of the
Commercialization of Products for all Indications in the Royalty-Bearing
Territory in accordance with the applicable GSK Product Commercialization Plan,
including without limitation the sole responsibility for booking sales of
Product and for Manufacturing all Product for use in the Royalty-Bearing
Territory, (b) the conduct of all pre-marketing, marketing, Branding,
promotion, sales, distribution, import and export activities (including
securing reimbursement, sales and marketing and conducting any post-marketing
trials or post-marketing safety surveillance or maintaining databases)
applicable to the Commercialization of Products for all Indications in the
Royalty-Bearing Territory, and (c) all of the activities described in Section 5.1.2(a) and
(b) in the U.S. Territory for any Product for which SYNTA exercises its
Commercialization Opt-Out Right as described in Sections 5.1.1(c) and    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   42


5.2, pursuant to the
applicable GSK Product Commercialization Plan. Notwithstanding the foregoing,
SYNTA shall have the right to import Product from, and export Product to, the
Royalty-Bearing Territory to the extent necessary to conduct the Ongoing
Clinical Trial and any other Clinical Trial for which it is responsible.  5.2           Exercise
of Commercialization Opt-Out Right.  If SYNTA exercises its Commercialization
Opt-Out Right as described in Section 5.1.1(c) with respect to a
particular Collaboration Compound by the Commercialization Opt-Out Date, (a) SYNTA
shall have no further obligation under this Agreement to fund any
Commercialization Expenses incurred with respect to the Commercialization of
any Product containing such Collaboration Compound on and after the
Commercialization Opt-Out Date; (b) GSK shall be [***] responsible for
funding [***] percent ([***]%) of the Commercialization Expenses incurred with
respect to the Products containing such Collaboration Compound in the
Territory; (c) the JCC shall be terminated as soon as practicable
thereafter unless SYNTA is conducting SYNTA Co-Commercialization Activities for
another Co-Commercialized Product with GSK; (d) GSK shall provide SYNTA
with [***] updates and reports with respect to its Commercialization activities
in the U.S. Territory with respect to Products containing such Collaboration
Compound in accordance with Section 5.6; (e) the Products for which
SYNTA exercised its Commercialization Opt-Out Right shall be deemed to be
Royalty-Bearing Products for purposes of this Agreement on and after the
Commercialization Opt-Out Date; (f) the amount of any agreed external
program expenses set forth in the applicable Commercialization Budget incurred
by SYNTA with respect to pre-marketing activities from the Effective Date shall be added to the payment to SYNTA from GSK for
achievement of the applicable [***] milestone, as set forth in Section 6.4.1(a),
so long as GSK determines that it is commercially reasonable to launch such
Products; (g) SYNTA will, in lieu of receiving any portion of the
Operating Income Payments with respect to such Products, receive the royalty
payments on Net Sales of such Products that occur in the U.S. Territory after
the Commercialization Opt-Out Date at the rates set forth in Section 6.5.1(b);
and (h) GSK shall have all decision-making authority for all
Commercialization matters with respect to such Products, including matters that
would otherwise be SYNTA Decisions or Unanimous Decisions in all Indications.  5.3           Commercialization
Plans.  (a)           Product Co-Commercialization Plan.  The Product Co-Commercialization Plans shall
be prepared and updated by [***]of
each [***] by, or at the direction of, the JCC, and approved by the JSC at such
time as the JSC may from time to time direct and in any event, on or prior to
the initiation of Commercialization activities with respect to the
Product.  Notwithstanding the foregoing,
the initial Product Co-Commercialization Plan shall be prepared within [***]
days after the Effective Date and shall cover at least the first [***] years of
Commercialization activities with respect to STA-4783 for the treatment of
metastatic melanoma, as well as a Commercialization Budget for such [***] years
(the plan and budget collectively referred to as Initial Product
Co-Commercialization Plan).  The Product
Co-Commercialization Plan shall be updated and approved at such times as the
JCC may determine, not less than annually.   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.  43


(b)           GSK Product Commercialization Plan.
Not later than [***] of each [***], GSK will provide SYNTA with a review and
update of the GSK Product Commercialization Plan applicable to the following
[***] and will give good faith consideration to SYNTAs comments on such GSK
Product Commercialization Plan.  The
first GSK Product Commercialization Plan shall be provided to SYNTA not later
than [***], 2008.  GSK will review the
GSK Product Commercialization Plan with SYNTA at one or more meetings of the
JSC and will provide SYNTA with annual updates of its progress with respect to
such GSK Product Commercialization Plan via the JSC.  GSK shall ensure that the GSK Product
Commercialization Plan is not inconsistent with the strategy agreed to by the
Parties in the Product Co-Commercialization Plan for the Co-Commercialization
Territory.  5.4           Commercialization
Diligence and Compliance. 
Each Party shall (a) use Commercially Reasonable Efforts during the
Term to Commercialize Products and conduct GSK Co-Commercialization Activities
or SYNTA Co-Commercialization Activities, as the case may be, (b) conduct the
activities as set forth in the applicable GSK Product Commercialization Plan
and/or the Co-Commercialization Agreement, and (c) commit such resources
(including employees, consultants, allowed contractors, facilities, equipment
and materials) as it deems necessary to conduct the activities described
above.  Each Party shall perform its
obligations under each Product Co-Commercialization Plan and
Co-Commercialization Agreement, and GSK shall perform its obligations under
each GSK Product Commercialization Plan in compliance in all material respects
with all Applicable Laws and with all applicable GSK Internal Policies.  5.5           Cooperation.  SYNTA and GSK shall cooperate in the
performance of any Product Co-Commercialization Plan and the
Co-Commercialization Agreement, subject to the terms of this Agreement and any
confidentiality obligations to Third Parties, and shall exchange such data,
information and materials as is reasonably necessary for the other Party to
perform its obligations under any Product Co-Commercialization Plan and the
Co-Commercialization Agreement.  5.6           Commercialization
Reports.Each Party shall
keep the JCC regularly informed of the conduct of the SYNTA
Co-Commercialization Activities and GSK Co-Commercialization Activities, as
applicable, for Co-Commercialized Products in the Co-Commercialization
Territory through periodic updates to the JCC. 
Without limiting the generality of the foregoing, each Party shall
provide the JCC with [***] written updates, which shall (a) summarize such
Partys conduct of SYNTA Co-Commercialization Activities and GSK
Co-Commercialization Activities, as applicable, for Co-Commercialized Products
in the Co-Commercialization Territory, (b) identify the Regulatory Filings
and Drug Approval Applications with respect to such Co-Commercialized Product
that such Party or any of its Affiliates have filed, sought or obtained in the
prior [***] month period or reasonably expect to make, seek or attempt to
obtain in the following [***] month period in the Co-Commercialization
Territory, and (c) summarize all Optional Phase 4 Clinical Trial data
generated by such Party with respect to such Co-Commercialized Product in the
Co-Commercialization Territory.  GSK
shall keep SYNTA regularly informed of the progress of its efforts to
Commercialize Products in the Royalty-Bearing Territory through [***] updates
to the JSC.   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.  44


5.7           Pharmacovigilance;
Adverse Event Reports.Within [***] days of the Effective Date, the Parties
will enter into the Pharmacovigilance Agreement, setting forth guidelines and
procedures for the receipt, investigation, recording, review, communication,
reporting and exchange between the Parties of adverse event reports (which, for
purposes of information exchange between the Parties, shall include Adverse
Events, as well as claims of lack of efficacy), technical complaints and any
other information concerning the safety of the Product.  Notwithstanding the foregoing, it is
contemplated that SYNTA shall maintain a unified worldwideAdverse Event
database for the Product, and be primarily responsible for reporting Adverse
Events to the applicable Regulatory Authorities until such time as the
Regulatory Filings, Drug Approval Applications, Regulatory Approvals and
Commercialization Regulatory Approvals for the U.S. Territory are transferred
to GSK pursuant to the Regulatory Filings Transfer Plan and this Agreement, and
thereafter, GSK shall maintain the unified worldwide Adverse Event database for
the Product, unless otherwise agreed by the Parties.  Costs associated with designing, maintaining
and installing the system supporting such database shall not be included in
Development Costs and shall be the responsibility of SYNTA.  5.8           Labeling.  All product labels and Promotional Materials
for Co-Commercialized Products shall include, in equal prominence, the names
and logos of both SYNTA and GSK to the extent feasible under Applicable
Laws.  GSK agrees that, to the extent
feasible under Applicable Laws and to the extent such statements are accurate
at the time of the sale of the Product, product labels for Co-Commercialized
Product will identify SYNTA as conducting Promotional Efforts for such
Co-Commercialized Product with GSK. The JCCshall have the responsibility of deciding whether changes in
the particular appearance in labeling of packaging and containers of
Co-Commercialized Products or in the product information is required.  6.             PAYMENTS  6.1           Up-front
Fee.  As partial
consideration for the licenses granted to GSK by SYNTA under the terms of this
Agreement, GSK will pay to SYNTA a non-refundable, non-creditable up-front fee
equal to eighty million dollars (US $80,000,000) within [***] Business Days of
the Effective Date, and upon receipt of an invoice from SYNTA, payable by wire
transfer of immediately available funds in accordance with wire transfer
instructions of SYNTA that shall be provided in writing to GSK prior to the
Effective Date.  6.2           Equity
Purchases.  6.2.1        Initial Equity Purchase Obligation.  In partial consideration of the rights
granted by SYNTA to GSK hereunder, on the Initial Equity Purchase Obligation
Date, GSK shall have the [***] (the Initial Equity Purchase Obligation) to
purchase from SYNTA, provided, that SYNTA may opt to [***] to GSK in its [***],
a number of shares of Common Stock, $.0001 par value per share, of SYNTA (SYNTA
Common Stock), as shall equal the applicable Share Purchase Number for the
Aggregate Equity Purchase Price, pursuant to the terms and subject to the
conditions set forth in a stock purchase agreement substantially in the form
attached hereto as Exhibit A (the Stock Purchase Agreement).  Notwithstanding the foregoing, in no event
shall (a) the aggregate number of shares of SYNTA Common Stock    Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   45


issuable under this Section 6.2.1
exceed [***]% of the total outstanding shares of SYNTA Common Stock or voting
power of SYNTA immediately prior to the execution of the Stock Purchase
Agreement or (b) GSK, individually or as part of a group, beneficially
own, or obtain the right to acquire, more than [***]% of the total outstanding
shares of SYNTA Common Stock or voting power of SYNTA immediately after the
issuance of SYNTA Common Stock under this Section 6.2.1; in the case of
(b), the Share Purchase Number and the Aggregate Equity Purchase Price shall be
reduced so that GSKs ownership percentage of outstanding shares of SYNTA
Common Stock does not exceed [***]%.  6.2.2        Subsequent Equity Purchase Right.  In partial consideration of the rights
granted by SYNTA to GSK hereunder, on the Subsequent Equity Purchase Right
Date, GSK shall have the [***] (the Subsequent Equity Purchase Right), which
it may opt to [***] in its [***], to purchase from SYNTA, provided, that SYNTA
may opt to [***] to GSK in its [***], a number of shares of SYNTA Common Stock
as shall equal the applicable Share Purchase Number for the Aggregate Equity
Purchase Price, pursuant to the terms and subject to the conditions set forth
in the Stock Purchase Agreement. 
Notwithstanding the foregoing, in no event shall (a) the aggregate
number of shares of SYNTA Common Stock issuable under this Section 6.2.2,
when taken together with the aggregate number of shares of SYNTA Common Stock
issued under Section 6.2.1, exceed [***]% of the total outstanding shares
of SYNTA Common Stock or voting power of SYNTA immediately prior to the
execution of the Stock Purchase Agreement or (b) GSK, individually or as
part of a group, beneficially own, or obtain the right to acquire, more than
[***]% of the total outstanding shares of SYNTA Common Stock or voting power of
SYNTA immediately after the issuance of SYNTA Common Stock under this Section 6.2.2;
in the case of (b), the Share Purchase Number and the Aggregate Equity Purchase
Price shall be reduced so that GSKs ownership percentage of outstanding shares
of SYNTA Common Stock does not exceed [***]%.   Portions of this Exhibit were omitted and have been filed separately
with the Secretary of the Commission pursuant to the Companys application
requesting confidential treatment under Rule 24b-2 of the Securities Exchange
Act of 1934.   46


Indication Based
  Milestone Events
  
  First Minor Indication
  ($ Million)
  
  Second Minor Indication($ Million)
  
  First Major Indication
  ($ Million)
  
  Second Major Indication($ Million)[***]
  for [***] in the[***] of [***] as[***] in [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  of the [***]for a [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***]The earlier of (a) the [***]by the [***] that
  the [***], or (b) the[***] by the [***] to [***] in the [***]for [***]
  for [***] in the [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  for a [***] in the [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***] for a [***] in the [***] for a [***] or any
  [***] if [***]not [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  for a [***] in [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  in the [***]for a [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  in the [***]or [***] for a[***]
  
  [***]
  
  [***]
  
  [***]
  
  [***][***]
  in [***] for a [***]
  
  [***]
  
  [***]
  
  [***]
  
  [***]Total
  
  [***]
  
  [***]
  
  [***]
  
  [***]  6.3           Operating
Income Payments.If the
Parties are conducting SYNTA Co-Commercialization Activities and GSK
Co-Commercialization Activities, as applicable, for a Co-Commercialization
Product in the Co-Commercialization Territory, then the Parties will share
Operating Income pursuant to the terms set forth in Schedule 4 hereto;
provided, that if SYNTA exercises its Commercialization Opt-Out Right pursuant
to Section 5.1.1(c), the provisions of Section 5.2 shall apply.  6.4           Milestone
Payments.  6.4.1        Milestones.  (a)           Development and
Regulatory Milestones. As partial consideration for the
licenses granted to GSK by SYNTA under the terms of this Agreement, GSKshall make the following non-refundable,
non-creditable (except as provided in Section 6.4.2(d) and Section 3.1.3(d))
payments to SYNTA:   Other Milestone Events
  
  MilestonePayment($ Millions)First [***] of the following [***] events to
  occur: the [***]by the [***] that [***] the [***] for [***] the [***]
  the[***] in the [***]
  
  [***] for each event, for a total of [***][***]
  of [***]
  
  [***][***]
  of [***] in a [***]
  
  [***][***]
  by the [***] that the [***] the [***]
  
  [***][***] of [***] of [***] and [***]
  
  [***]Total
  
  [***]   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   47


(b)           Sales Milestones.  In addition to the milestone payments
contemplated by Section 6.4.1(a), GSKshall
make the following non-refundable payments to SYNTA:  Milestone Event
  
  Milestone
  Payment[***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***][***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***][***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***][***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***][***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***][***] of [***] in the [***] in a [***] of
  [***]
  
  $
  [***]  6.4.2        Notice and Payment of
Milestones.  (a)           Notice
of Milestone Events.  Either Party
shall provide the other Party with prompt written notice upon each occurrence
of a milestone event set forth in Section 6.4.1, but in no event will such
notice be given to such other Party later than [***] Business Days after the
notifying Party becomes aware of the achievement of any milestone.  The milestones will be paid within [***]
Business Days of the date on which GSK receives an invoice from SYNTA with
respect to such milestone.  If,
notwithstanding the fact that GSKhas
not given SYNTA notice of the achievement of a milestone, SYNTA believes any
such milestone event has occurred, it shall so notify GSKin writing and shall provide to GSKdata, documentation or other information
that supports its belief.  Any dispute
under this Section 6.4.2 that relates to whether or not a milestone event
has occurred shall first be referred to the JSC to be resolved in accordance
with Section 2.1.5.  (b)           Skipped
Milestones.  If, at the time any
given milestone payment set forth in Section 6.4.1 is due and one or more
preceding milestone payments for antecedent milestone events have not been
paid, then such unpaid antecedent milestone payments shall be paid at such time
as well.  For example, if a milestone
payment is made for the [***] of an [***]    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   48


to a [***] for the second Major Indication but no [***] [***] with
[***] to that [***] for the second Major Indication, the milestone payment
associated with the [***] of the [***] for a [***] for that [***] will be paid
concurrently with the milestone payment for the [***] of an [***] for the
second Major Indication.  (c)           Changes to Status
of [***] Indications.  If a Product
that is approved for a [***] Indication achieves Annual Net Sales in such [***]
Indication in the Territory of at least [***] dollars ($[***]), GSK shall pay
the difference between the total milestones paid for such [***] Indication and
the milestones payable for a [***] for a [***] within [***] Business Days of
the date on which GSK receives an invoice from SYNTA (after notification from
GSK that such sales threshold has been met), so long as the milestones payable
for [***] set forth in Section 6.4.1(a) have not been paid with
respect to the [***].  If some, but not
all milestone payments have been made for either one or both [***], this
payment will reflect the difference between the [***] for a [***] and the [***]
for the [***] ([***] Milestones [***] [***]). 
By way of illustration, if [***] for the [***] Minor Indication [***]
for a Product approved for the Indication of [***], [***] for the [***] Minor
Indication [***] for a Product approved for the Indication of [***], [***] for
the [***] for a [***] for the [***], and [***] for the [***], then on
achievement of [***] of the [***] for the [***] of at least [***] dollars
($[***]), then a payment of $[***] shall be due to SYNTA, representing the
difference between the [***] of $[***] for a Product approved for a [***] and
[***] of $[***] for a Product approved for a Minor Indication and already paid
to SYNTA for the [***] in [***].  For the
avoidance of doubt, if [***] for the [***] [***] prior to the [***] for the
[***] achieving [***] of [***] dollars ($[***]), then the [***] described in
the foregoing example [***].  (d)Single
Milestone Payments.  For purposes
of clarity, GSK shall make a milestone payment corresponding to each of the
foregoing milestone events [***] under  Section 6.4.1,
[***] of the [***] for such Product or the [***] for which such Product is
Developed or Commercialized.  For example,in theevent that a [***] for an Indication for a Product and Development of
such Product for suchIndicationis subsequently terminated, such [***] shall be [***] for a [***]for the [***]
or for the [***] for [***] of whether such [***] is a [***] or [***].  (e)           [***] Clinical
Trials.  The payment by GSK of a
milestone for the achievement of the [***] Criteria in either the [***] Trial
as set forth above shall only be paid to the extent that SYNTA [***] associated
with such [***] Trials.  6.5           Payment of Royalties; Royalty Rates; Accounting and
Records.  6.5.1             Payment of Royalties.  (a)           Royalties
Applicable in ROW Territory.  (i)            Subject to the adjustments, if any,
on a country-by-country and Royalty-Bearing Product-by-Royalty-Bearing Product
basis set forth in Section 6.5.1(c) below, GSKshall pay SYNTA a royalty on Annual Net
Sales of all Royalty-Bearing Products in the Royalty-Bearing Territory in each
Calendar Year (or partial Calendar Year) for the Royalty Term applicable to
each Royalty-Bearing Product in each country, at the following rates:    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   49


Annual Net Sales
  Increment on All
  Products in ROW Territory
  
  Royalty
  Rate (%)Up to and including $[***]
  
  [***]%Above $[***], and up to
  and including $[***]
  
  [***]%Above $[***]
  
  [***]%
  (ii)           The following hypothetical example
illustrates the calculation of royalties under Section 6.5.1(a)(i): if, in
any Calendar Year during the Term, Annual Net Sales of a Royalty-Bearing
Product in the Royalty-Bearing Territory are $[***], the applicable royalty
would be $[***], [***]% of Net Sales for Net Sales up to $[***], and [***]% of
Net Sales for Net Sales of $[***].  The
following hypothetical example illustrates a further calculation of royalties
under Section 6.5.1(a)(i): if, in any Calendar Year during the Term,
Annual Net Sales of two (2) Royalty-Bearing Products in the
Royalty-Bearing Territory are $[***] and $[***] respectively, thereby totaling
$[***] for all Products, the applicable royalty would be $[***], [***]% of Net
Sales for Net Sales up to $[***], and [***]% of Net Sales for Net Sales of
$[***]  (b)           Royalties
Applicable in U.S. Territory.  (i)            If SYNTA exercises its
Commercialization Opt-Out Right with respect to a Product on or before the
Commercialization Opt-Out Date, (A) such Product shall thereafter be a
Royalty-Bearing Product for purposes of this Agreement; and (B) subject to
the adjustments, if any, on a Royalty-Bearing Product-by-Royalty-Bearing
Product basis set forth in Section 6.5.1(c) below, GSKshall pay SYNTA a royalty based on Annual
Net Sales of all such Royalty-Bearing Products in each Calendar Year (or
partial Calendar Year) for the Royalty Term (which commences upon the First
Commercial Sale of such Royalty-Bearing Product in the U.S. Territory after the
Commercialization Opt-Out Date) applicable to such Royalty-Bearing Product in
the U.S. Territory, at the following rates:  Annual
  Net Sales Increment on All
  Products in U.S. Territory
  
  Royalty Rate (%)Up
  to and including $[***]
  
  [***]%Above
  $[***], and up to and including $[***]
  
  [***]%Above
  $[***]
  
  [***]%
  (c)           Adjustments to
Royalties.  (i)            No Patent Coverage; Joint Patent
Coverage.  Notwithstanding anything
to the contrary in Section 6.5.1(a) or (b), if any Royalty-Bearing
Product is sold in a country and is not covered by a Valid Claim that is
included in SYNTA Patent Rights in such country, or is only covered by a Valid
Claim that is included in Joint Patent    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    50


Rights, then the royalty
rates in such country shall be reduced by [***] percent ([***]%) of the rates
set forth in Section 6.5.1(a) and/or (b) above, continuing until
the last day of the applicable Royalty Term with respect to such
Royalty-Bearing Product.  If the royalty
rate on a Royalty-Bearing Product is reduced in a country under this Section 6.5.1(c)(i) and
is subsequently covered by a Valid Claim under the SYNTA Patent Rights in such
country, the full royalty rates otherwise applicable under Section 6.5.1(a) or
(b), as the case may be, shall be reinstated for so long as such Valid Claim
covers the Royalty-Bearing Product during the remainder of the applicable
Royalty Term.  In addition, if a
particular Royalty-Bearing Product is covered by a Valid Claim of a pending
patent application included in the SYNTA Patent Rights or Joint Patent Rights,
but is not covered by a Valid Claim of an issued patent included in the SYNTA
Patent Rights or Joint Patent Rights at the time of the First Commercial Sale
of such Royalty-Bearing Product in a particular country,then the
royalty rates for such Royalty-Bearing Product in such country shall be reduced
by [***] percent ([***]%) of the royalty rates set forth in Section 6.5.1(a) and/or
6.5.1(b) (as adjusted in this Section 6.5.1(c)(i) with respect
to coverage by Valid Claims of Joint Patent Rights only) for the applicable
Royalty Term; provided, that any such pending application shall no longer
qualify under this Section 6.5.1(c)(i) ifit has been finally
withdrawn, abandoned or rejected by any administrative agency or other body of
competent jurisdiction from which no appeal can be taken, or(ii) it is
pending for more than [***] years from the date of the first official
action.The payments representing
the remaining [***] percent ([***]%) that would otherwise have been payable to
SYNTA if the pending patent application was an issued patent included within
the SYNTA Patent Rights or Joint Patent Rights shall be deposited into a Third
Party escrow account to be maintained by GSK on behalf of SYNTA.  Upon the issuance of a patent based upon the
pending patent application described above with a Valid Claim covering the
Royalty-Bearing Product in such country, prior to expiration of the applicable
Royalty Term for such Royalty-Bearing Product, the remaining [***] percent
([***]%), plus interest accrued to such escrow account, shall be promptly paid
to SYNTA.  If a patent does not issue
from such pending patent application during the applicable Royalty Term, then
GSK shall retain all such amounts paid into escrow, plus interest accrued to
such escrow account.  In addition, if, and for so
long as Competing Products are sold in the applicable country as described in Section 6.5.1(c)(iv) or
reductions in royalty payments are taken in accordance with Section 6.5.1(c)(v) with
respect to such Royalty-Bearing Product in such country, then GSK shall apply
the applicable reduction on the escrowed portion and the applicable reduction
on the non-escrowed portion such that, together, the escrowed portion and the
non-escrowed portion of royalties represent the appropriate overall reduction
as set forth in Section 6.5.1(c)(iv) and Section 6.5.1(c)(v),
subject to the limitation set forth in Section 6.5.1(c)(vi).  (ii)           Acknowledgment.  The Parties hereby acknowledge and agree that
royalties that are payable for a Royalty-Bearing Product for which no Patent
Rights exist shall be in consideration of (A) SYNTAs expertise and
know-how concerning its development of the SYNTA Technology and its other
development activities conducted prior to the Effective Date; (B) the
performance by SYNTA of the [***]; (C) the disclosure by SYNTA to GSKof results obtained in the Development
Program; (D) the licenses granted to GSKhereunder with respect to SYNTA Technology and Joint Technology
that are not within the claims of any Patent Rights Controlled by
SYNTA; (E) the restrictions on SYNTA in Section 8.4.1; (G) the head
start afforded to GSKby each of
the foregoing; and (H) SYNTAs conduct of [***] of [***] in the [***].    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   51


(iii)          Combination Products.  In the event that a Royalty-Bearing Product
is sold as part of a Combination Product, where Combination Product means any
unified dose (e.g. not a kit of two separate and distinct drug dosage forms) of
a pharmaceutical product which is comprised of Royalty-Bearing Product and one
or more other compound(s) and/or ingredients having independent
therapeutic effect (collectively the Other Products), Net Sales of
Royalty-Bearing Product, for the purposes of determining royalty payments,
shall be determined by multiplying the Net Sales of the Combination Product by
the fraction, [***] where A is the weighted average sale price of the
Royalty-Bearing Product when sold separately in finished form, and B is the
weighted average sale price of the Other Products when sold separately in
finished form, in each case in the country of sale of the Combination
Product.  In the event that no such
separate sales are made of either the Royalty-Bearing Product or the Other
Products, the reasonably estimated commercial value thereof will be used
instead of the sale price.  For purposes
of this Section 6.5.1(c)(iii), (A) weighted average sale price and reasonably
estimated commercial value, as the case may be, for a Royalty-Bearing Product
and Other Products shall be calculated once at the commencement of each
Calendar Year and such amount shall be used during all applicable royalty
reporting periods for the entire following Calendar Year, (B) the weighted
average sale price shall be calculated by dividing the Net Sales in the ten
countries with the highest Net Sales or such other countries as collectively
comprise [***] percent ([***]%) or more of Net Sales by the units of active
ingredient sold during the twelve (12) months (or the number of months sold in
a partial Calendar Year) of the preceding Calendar Year for the respective
Product or Other Products, and (C) reasonably estimated commercial value
shall be determined by agreement of the Parties using criteria to be mutually
agreed upon by the Parties; provided, that if the Parties do not agree, such
dispute shall be resolved in accordance with Section 2.1.5 hereof.  For purposes of clarity, in the first
Calendar Year of sale, a forecasted weighted average sale price will be used
for the Royalty-Bearing Product and Other Products, if applicable, and any over
or under payment due to a difference between forecasted and actual weighted
average sale prices will be paid or credited in the first royalty payment of
the following Calendar Year.  (iv)          Competing Drugs.  In the event that one or more Third Parties
sell a Competing Drug (as defined below) in any country in which a
Royalty-Bearing Product is then being sold by GSK, then, (A) during any
Calendar Quarter in which sales of the Competing Drug by such Third Parties are
equal to or greater than [***] percent ([***]%) but less than [***] percent
([***]%) of aggregate unit sales of Royalty-Bearing Products and Competing
Drugs in such country (as measured by prescriptions or other similar information
available from a Third Party Data Provider and applicable to such country) the
applicable royalties in effect with respect to such Royalty-Bearing Product in
such country as specified in Section 6.5.1(a) or (b) or 6.5.1(c)(i) shall
be reduced by [***] percent ([***]%) and (B) during any Calendar Quarter
in which sales of the Competing Drug by such Third Parties are equal to or
greater than [***] percent ([***]%) of aggregate unit sales of Royalty-Bearing
Products and Competing Drugs in such country (as measured by prescriptions or
other similar information available from a Third Party Data Provider and
applicable to such country) the applicable royalties in effect with respect to
such Royalty-Bearing Product in such country as specified in Section 6.5.1(a) or
(b) or 6.5.1(c)(i) shall be reduced by [***] percent ([***]%).  Notwithstanding the foregoing, (I) GSKs
obligation to pay royalties at [***] percent ([***]%) of the applicable royalty
rates shall be reinstated on the first day of the Calendar Quarter    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   52


immediately following the
Calendar Quarter in which sales of such Competing Drugs account for less than
[***] percent ([***]%) but more than [***] percent ([***]%) of aggregate unit
sales of Royalty-Bearing Products and Competing Drugs in such country and (II) GSKs
obligation to pay royalties at the full royalty rates shall be reinstated on
the first day of the Calendar Quarter immediately following the Calendar
Quarter in which sales of such Competing Drugs account for [***] percent
([***]%) or less of aggregate unit sales of Royalty-Bearing Products and
Competing Drugs in such country.  For
purposes of this Section 6.5.1(c)(iv), a Competing Drug means
[***].  For purposes of this Section 6.5.1(c)(iv),
the amount of royalties owing to SYNTA under Sections 6.5.1(a)(i), 6.5.1(b)(i) or
6.5.1(c)(i) for Annual Net Sales of any Royalty-Bearing Product in a given
country (prior to any [***]% adjustment provided for herein) shall be deemed to
be that amount which would be owed if Annual Net Sales of such Royalty-Bearing
Product in such country subject to each of the royalty rates under Sections
6.5.1(a)(i), 6.5.1(b)(i) or 6.5.1(c)(i) were proportional to Net
Sales of such Royalty-Bearing Product in all countries subject to royalties
under Sections 6.5.1(a)(i), 6.5.1(b)(i) or Section 6.5.1(c)(i),
whichever is applicable.  For purposes of
clarity, an example of the application of the preceding sentence is as
follows:  If sales in a Calendar Year in
the United Kingdom are $[***] and no Competing Drug is sold in the United
Kingdom and sales in a Calendar Year in Germany are $[***] and sales of a
Competing Drug in Germany are greater than [***] percent ([***]%) of aggregate
unit sales of Royalty-Bearing Products and Competing Drugs in Germany, the
royalties will be $[***], calculated as follows: ($[***] x [***]% + [***] x
[***]%) + ($[***] x [***]% + [***] x [***]%) = $[***].  (v)           Third Party Royalties.The
amount of royalties payable to SYNTA under Section 6.5.1(a), Section 6.5.1(b) and/or
Section 6.5.1(c)(i), in each case, for any Royalty-Bearing Product in any
country, shall be reduced by [***] percent ([***]%) of the amount of royalties
incurred by GSK or any of its Affiliates or Sublicensees to any Third Party in
consideration for the license of Patent Rights that are required for the
commercial success of the Royalty-Bearing Product (i.e. there is no reasonable
commercially viable alternative to the license of such Patent Rights, or such
Patent Rights are not merely useful for the commercial success of the
Royalty-Bearing Product) in such country and if, at the time of sale of the
Royalty-Bearing Product, such Patent Rights would be infringed by the sale of
the Royalty-Bearing Product in such country in the absence of such a license;
provided, that royalties payable to SYNTA with respect to sales in any country
shall not be reduced by greater than [***] percent ([***]%) of the royalty
rates set forth in Sections 6.5.1(a), 6.5.1(b) or 6.5.1(c), as the case
may be.  For purposes of clarity, an
example of the application of the preceding sentence is as follows:  If sales in a Calendar Year in countries in
the ROW Territory without royalty owed to Third Parties are $[***] and sales in
countries in the ROW Territory with a [***] percent ([***]%) royalty owed to
Third Parties are $[***], the royalties will be $[***], calculated as
follows:  ($[***] x [***]% + [***] x
[***]%) + ($[***] x [***]% + [***] x [***]%) = $[***].  Notwithstanding the foregoing, any royalties
(or any other payments) to be paid to Third Parties under the Third Party
Agreements shall be the sole responsibility of SYNTA.  (vi)          Limit on Royalty Reductions.  Notwithstanding anything to the contrary in Section 6.5.1(c),
in no event shall the royalties owed under Section 6.5.1(a)(i) or Section 6.5.1(b)(i) with
respect to a Royalty-Bearing Product in a country, as adjusted pursuant to
Sections 6.5.1(c)(i) and 6.5.1(c)(iii), be reduced by operation of Section 6.5.1(c)(v),
together     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   53


with Section 6.5.1(c)(iv),
by more than [***] percent ([***]%). For clarity, if the royalty on a
particular Royalty-Bearing Product in a given country was payable at [***]%,
[***]% and [***]% under Section 6.5.1(a)(i), then the royalty rate in such
country for such Royalty-Bearing Product could not be reduced below [***]%,
[***]% and [***]%, pursuant to the aggregate application of both Sections
6.5.1(c)(iv) and 6.5.1(c)(v).  For
further clarity, if the royalty on a particular Royalty-Bearing Product in a
given country was payable at [***]%, [***]% and [***]% under Section 6.5.1(a)(i) as
adjusted by Section 6.5.1(c)(i), then the royalty rate in such country for
such Royalty-Bearing Product could not be reduced below [***]%, [***]% and
[***]%, pursuant to the aggregate application of both Sections 6.5.1(c)(iv) and
6.5.1(c)(v).  6.6           Payment
Dates and Reports. 
Royalty payments shall be made by GSK within [***] days after the end of
each Calendar Quarter, commencing with the Calendar Quarter in which the First
Commercial Sale of a Royalty-Bearing Product occurs.  GSK shall also provide, at the same time each
such payment is made, a report showing: (a) the [***] of each
Royalty-Bearing Product by type of Royalty-Bearing Product and country in the
Territory; (b) the [***] for Royalty Bearing Product in each country in
the Territory after applying any reductions set forth above; and (c) a
calculation of the amount of royalty due to SYNTA.  6.7           Records;
Audit Rights.  GSK, its
Affiliates and Sublicensees shall keep and maintain for [***] years from the
date of each payment of royalties hereunder complete and accurate records of
gross sales and Net Sales by GSK, its Affiliates and Sublicensees of each
Royalty-Bearing Product, in sufficient detail to allow royalties to be determined
accurately by an independent certified public accountant.  SYNTA shall have the right for a period of
[***] years after receiving any such payment to appoint at its expense an
independent certified public accountant reasonably acceptable to GSK to audit
the relevant records of GSK and its Affiliates and Sublicensees to verify that
the amount of such payment was correctly determined.  GSK, its Affiliates and Sublicensees shall
each make its records available for audit by the independent certified public
accountant during regular business hours at such place or places where such
records are customarily kept (for clarity these records may be kept at local
business sites and not centrally in one location), upon [***] days written
notice from SYNTA.  Such audit right
shall not be exercised by SYNTA more than once in any Calendar Year or more
than [***] with respect to sales of a particular Royalty-Bearing Product in a
twelve (12) month period.  The
independent certified public accountant will only disclose the results (any
sums either over/under paid) of such audit to SYNTA and no other details.  All records made available for audit shall be
Confidential Information of GSK.  In the
event there was an underpayment by GSK or overpayment to SYNTA hereunder, then
the relevant Party shall promptly (but in any event no later than [***] days
after GSKs receipt of the report so concluding) make payment to the other
Party of any amount due.  SYNTA shall
bear the full cost of such audit unless such audit discloses an underreporting
by GSK of at least [***] percent ([***]%) of the aggregate amount of royalties
payable in any Calendar Year, in which case GSK shall reimburse SYNTA for all
costs incurred by SYNTA in connection with such audit.  6.8           Overdue
Payments. All royalty
payments not made within the time period set forth in Section 6.6,
including underpaymentsdiscovered
during an audit, and all milestone payments not made within the time period
specified in Section 6.4.2(a), shall bear interest at a rate of [***]
percent ([***]%) per month from the due date until paid in full or, if less,
the     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   54


maximum interest rate
permitted by Applicable Laws.  Any such
overdue royalty or milestone payment shall, when made, be accompanied by, and
credited first to, all interest so accrued. 
Such interest will not accrue on payments that are the subject of a
Disputed Matter or if delay in payment is outside the reasonable control of the
paying Party.  6.9           Payments;
Withholding Tax.  6.9.1        Payments
in U.S. Dollars.  All
payments made by a Party under this Article 6 shall be made by wire
transfer in U.S. Dollars in accordance with instructions given in writing from
time to time by the other Party.  6.9.2        Withholding
Taxes.  Any taxes, levies
or other duties paid or required to be withheld or deducted underthe
appropriate Applicable Laws by one of the Parties on account of monies payable
to the other Party under this Agreement shall be deducted from the amount of
monies otherwise payable to the other Party under this Agreement.  The withholding Party shall secure and send
to the other Party within a reasonable period of time, proof of any such taxes,
levies or other duties paid or required to be withheld by the withholding Party
for the benefit of the other Party.  The
Parties shall cooperate reasonably with each other to ensure that any amounts
required to be withheld by either Party are reduced in an amount to the fullest
extent permitted by Applicable Laws.  Any
interest, penalties or other charges imposed by a governmental authority as a
result of a failure by the withholding party to pay such taxes, levies or other
duties shall be the responsibility of the withholding party.  The other Party will give the withholding
Party any information necessary to determine such taxes, levies or other
duties.  No deduction shall be made, or a
reduced amount shall be deducted, if the other Party furnishes a document from
the appropriate governmental authorities to the withholding Party certifying
that the payments are exempt from such taxes, levies or other duties or subject
to reduced tax rates, according to the applicable convention for the avoidance
of double taxation.  6.10         Foreign
CurrencyExchange.  All payments to be made by GSK to SYNTA under
this Agreement shall be made in United States dollars and may be paid by check
made to the order of SYNTA or bank wire transfer in immediately available funds
to such bank account in the United States as may be designated in writing by
SYNTA from time to time.  If, in any
Calendar Quarter, Net Sales are made in any currency other than United States
Dollars, such Net Sales shall be converted into United States Dollars as
follows:  (A/B), where  A = foreign Net Sales
(as defined above) in such Calendar Quarter expressed in such foreign currency;
and  B
= foreign exchange conversion rate, expressed in local currency of the foreign
country per United States Dollar.  The
rate of exchange to be used in computing the amount of currency equivalent in
United States Dollars owed to SYNTA under this Agreement will be made in
accordance with GSKs policy for foreign exchange.  GSK will use the average exchange rates as
calculated and utilized by GSKs group reporting system and published
accounts.  The current GSK policy uses
spot exchange rates sourced from   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    55


Reuters/Bloomberg
and if changed, GSK will notify SYNTA of the revised method in advance of it
being applied.  6.11         Invoices.  All invoices provided to GSK hereunder should
include the payees bank details and SYNTAs contact name for issue resolution,
and be sent to Corporate Accounting and Licensing at GSK.  Additional details regarding the method of
sending invoices to GSK, contact names and addresses will be provided to SYNTA
by GSK promptly after the Execution Date.  7.             TREATMENT OF CONFIDENTIAL INFORMATION; PUBLICITY.  7.1           Confidentiality.  7.1.1        Confidentiality
Obligations.  SYNTA and
GSK each recognizes that the other Partys Confidential Information constitutes
highly valuable assets of such other Party. 
SYNTA and GSK each agrees that, subject to Sections 7.1.2 and 9.3, (i) it
will not disclose, and will cause its Affiliates and Sublicensees not to
disclose, any Confidential Information of the other Party and (ii) it will
not use, and will cause its Affiliates and Sublicensees not to use, any
Confidential Information of the other Party except as expressly permitted
hereunder; provided, that, such obligations shall apply during the Term and for
an additional [***] years thereafter.  7.1.2        Limited
Disclosure.  SYNTA and GSK
each agrees that disclosure of its Confidential Information may be made by the
other Party to any employee, consultant or Affiliate of such other Party or
Third Party subcontractor engaged by a Party pursuant to Section 8.2.1 to
enable such other Party to exercise its rights or to carry out its
responsibilities under this Agreement; provided, that, any such disclosure or
transfer shall only be made to such employees, consultants, Affiliates or Third
Party subcontractors who are bound by written obligations of confidentiality as
described in Section 7.1.3.  In
addition, SYNTA and GSK each agrees that the other Party may disclose its
Confidential Information, pursuant to written obligations of confidentiality as
described in Section 7.1.3, (a) to its licensees as expressly
permitted pursuant to Section 8.2 hereof, (b) on a need-to-know basis
to such other Partys legal and financial advisors, (c) as reasonably
necessary in connection with an actual or potential (i) permitted
sublicense of such other Partys rights hereunder, (ii) debt or equity
financing of such other Party or (iii) merger, acquisition, consolidation,
share exchange or other similar transaction involving such Party and any Third
Party and (d) to any Third Party that is or may be engaged by a Party to
perform services in connection with the Development Program, the SYNTA
Co-Commercialization Activities, the GSK Co-Commercialization Activities or the
Commercialization of Products as necessary to enable such Third Party to
perform such services.  In addition, each
Party agrees that the other Party may disclose such Partys Confidential
Information (A) as reasonably necessary to file, prosecute or maintain
Patent Rights, or to file, prosecute or defend litigation related to Patent
Rights, in accordance with this Agreement; or (B) as required by
Applicable Laws (which shall be determined by the disclosing Party in its
reasonable discretion); provided, that, in the case of any disclosure under
this clause (B), the disclosing Party shall (1) if practicable, provide
the other Party with reasonable advance notice of and an opportunity to comment
on any such required disclosure and (2) if requested by the other Party,
cooperate in all reasonable respects with the other Partys efforts to obtain   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    56


confidential treatment or a
protective order with respect to any such disclosure, at the other Partys
expense.  7.1.3        Employees
and Consultants.  SYNTA
and GSK each hereby represents that all of its employees and consultants, and
all of the employees and consultants of its Affiliates, who have access to
Confidential Information of the other Party are or will be bound, prior to
their participation or access, by written obligations to maintain such
Confidential Information in confidence. 
Each Party agrees to use, and to cause its Affiliates to use, reasonable
efforts to enforce such obligations and to prohibit its employees and
consultants from using such information except as expressly permitted
hereunder.  Each Party will be liable to
the other for any disclosure or misuse by its employees of Confidential
Information of the other Party.  7.2           Publicity.  Notwithstanding anything to the contrary in Section 7.1,
the Parties, upon the execution of this Agreement, shall jointly issue a press
release with respect to this Agreement in the form attached hereto as Schedule
5, and either Party may make subsequent public disclosures of the contents
of such press release without further approval of the other Party. After
issuance of such press release, except as required by Applicable Laws
(including those relating to disclosure of material information to investors),
neither Party shall issue a press or news release or make any similar public
announcement (it being understood that publication in scientific journals,
presentation at scientific conferences and meetings and the like are intended
to be covered by Section 7.3 and not subject to this Section 7.2)
related to the Development Program without the prior written consent of the
other Party, and shall provide such other Party with a copy of the proposed
press or news release or similar public announcement for review in advance;
provided, that notwithstanding the foregoing, either Party shall be expressly permitted
to publicly announce the presentation of data pursuant to Section 7.3 with
respect to Collaboration Compounds at any scientific or medical meeting or
conference, the Initiation or completion of any Clinical Trial with respect to
a Collaboration Compound, the occurrence of any milestone event and, if
determined by SYNTA to be material to SYNTA, the amount of any milestone
payment under Section 6.4.1 and any other event that such Party reasonably
believes is material to it and the other Party shall not unreasonably withhold,
condition or delay its consent to any such request to make such public
announcement by the other Party.  7.3           Publications
and Presentations.  The
Parties acknowledge that scientific and medical publications and presentations
will be made in a manner consistent with (a) Third Party agreements in
effect as of the Effective Date and (b) subject to subsection (a), GSK
Internal Policies, but must be strictly monitored to prevent any adverse effect
from premature publication or dissemination of results of the activities
hereunder.  The Parties will form a
publication committee (the Publication Committee) as soon as reasonably
practicable after the Effective Date, with representation from patent counsel
as deemed necessary, which shall work together on publication strategy with the
JDC and JCC to coordinate strategy with respect to the U.S. Territory, with
coordination by GSK of strategy on a ROW Territory basis, and shall establish rules and
procedures for scientific and medical publications and presentations relating
to the Development and Commercialization activities conducted under the
Collaboration.  Such rules and
procedures will include requirements for reasonable advance notice and
expeditious review    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   57


of proposed publications and
presentations, both before and after Commercialization Regulatory Approval is
obtained.  Except for disclosures
permitted pursuant to Section 7.2, the rules and procedures to be
developed by the Publication Committee will require that (i) either Party,
its employees or consultants wishing to make a publication shall deliver to the
other Party a copy of the proposed written publication or an outline of an oral
disclosure in advance of submission for publication or presentation in
accordance with the timelines set forth in GSK Internal Policies or applicable
Third Party agreements in effect as of the Effective Date, (ii) the
reviewing Party shall have the right to require a delay in submission for
publication or presentation in accordance with the timelines set forth in GSK
Internal Policies or applicable Third Party agreements in effect as of the
Effective Date in order to enable patent applications protecting each Partys
rights in such information to be filed, and (iii) each Party shall have
the right to prohibit disclosure of any of its Confidential Information in any
such proposed publication or presentation. 
In any permitted publication or presentation by a Party, the other Partys
contribution shall be duly recognized, and co-ownership shall be determined in
accordance with GSK Internal Policies. 
In negotiating agreements with Third Parties, each Party shall use
Commercially Reasonable Efforts to obtain the agreement of such Third Party to
the timelines for review and delay of submission as set forth in GSK Internal
Policies.  7.4           Permitted
Publications.  GSK shall
be permitted, to the extent required by Applicable Laws and/or the GSK Internal
Policies, to publish summaries of the results of all Clinical Trials conducted
by either Party on GSKs Clinical Trial Register.  Either Party shall be permitted to include in
a public disclosure or in a scientific or medical publication or presentation,
any information which has previously been approved by the Parties for public disclosure
or included in a public disclosure or scientific or medical publication that
has been approved pursuant to Section 7.2 or reviewed pursuant to Section 7.3
or published or publicly disclosed by the other Party that, in any case, does
not materially alter the message of the previous disclosure.  8.             LICENSE GRANTS; EXCLUSIVITY;
STANDSTILL AGREEMENT  8.1           Licenses.  8.1.1        SYNTA
License Grants.Subject
to the other terms of this Agreement, SYNTA hereby grants to GSK, during the
Term, an exclusive (subject to SYNTAs retention of certain rights as set forth
below) royalty-bearing, worldwide license or sublicense (with respect to SYNTA
Technology and SYNTA Patent Rights licensed by third parties to SYNTA), with
the right to grant sublicenses solely as provided in Section 8.2, under
SYNTA Technology, SYNTA Patent Rights and SYNTAs interest in Joint Patent
Rights and Joint Technology to make, have made, use, sell, offer for sale and
import Products in the Territory. 
Notwithstanding the foregoing, SYNTA shall retain the right under SYNTA
Technology and SYNTA Patent Rights to conduct SYNTA Development Activities as
part of the Development Program and SYNTA Co-Commercialization Activities for
Co-Commercialized Products in the Co-Commercialization Territory.  For clarity, the retention of rights by SYNTA
described in the foregoing sentence shall terminate on a [***] basis (a) with
respect to SYNTA Development Activities if SYNTA exercises its Development
Opt-Out Right in accordance with Section 3.1.3(d) and/or (b) with
respect to conduct of the SYNTA Co-Commercialization Activities for
Co-Commercialized    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   58


Products if SYNTA exercises
its Commercialization Opt-Out Right as set forth in Section 5.1.1(c).  8.1.2        GSK
License Grants.Subject
to the other terms of this Agreement, GSK hereby grants to SYNTA, during the
Term, an exclusive (except as to GSK), royalty-free license, with the right to
grant sublicenses solely as provided in Section 8.2.1, under GSK
Technology, GSK Patent Rights and GSKs interest in Joint Technology and Joint
Patent Rights for the sole purpose of conducting SYNTA Development Activities
as part of the Development Program in the U.S. Territory and to conduct SYNTA
Co-Commercialization Activities for Co-Commercialized Products in the
Co-Commercialization Territory.  8.1.3Sublicenses Under Third Party Agreements.If the JPC determines that a sublicense to the
Technology and Patent Rights licensed to SYNTA under either or both of the
Third Party Agreements is desirable for the Development or Commercialization of
Products hereunder, GSK shall so notify SYNTA in writing, whereupon the Patent
Rights and Technology under the applicable Third Party Agreements specified in
such notice shall become SYNTA Patent Rights and SYNTA Technology
hereunder.  In such event, SYNTA shall be
responsible for any and all milestone and royalty payments due to the licensors
under the Third Party Agreements.For
clarity, the Patent Rights and Technology licensed to SYNTA under the Third Party
Agreements shall not be included in the licenses granted to GSK hereunder
unless and until GSK provides the foregoing written notice to SYNTA.  8.2           Right
to Sublicense.  8.2.1        Development. Notwithstanding anything contained
herein to the contrary, either Party shall have the right to grant sublicenses
under the license granted to it under Sections 8.1.1 and 8.1.2, respectively,
solely to Third Party subcontractors engaged by such Party to perform
designated functions related to the conduct of SYNTA Development Activities or
GSK Development Activities, as the case may be, under the Development Program
or to Affiliates; provided,that (a) such Party
[***] to each material sublicense grant, such approval [***]; (b) such
Party shall remain responsible for the satisfactory accomplishment of such work
in accordance with the terms and conditions of this Agreement; and (c) each
such Third Party subcontractor shall enter into a written agreement containing
such provisions as are normal and customary for similar types of
agreements.  For the avoidance of doubt,
GSK shall not be required to obtain approval of the JDC with respect to
sublicenses granted to its Affiliates, or sub-contracting out its Manufacturing
activities in the Territory.  8.2.2        Commercialization.  GSK shall have the right to grant
sublicenses to Sublicensees under the license granted to it under Section 8.1.1
with respect to Royalty-Bearing Products for sale in the Royalty-Bearing
Territory; provided, that, (a) to the extent any such sublicense is with
respect to[***] except that GSK
may utilize a contract sales organization in the Royalty-Bearing Territory and
in the Co-Commercialization Territory if both GSK and SYNTA are unable to
provide their respective requirements of Representatives necessary to conduct
the GSK Co-Commercialization Activities or SYNTA Co-Commercialization
Activities, as the case may be, in its discretion upon prior notice to SYNTA; (b) it
shall be a condition of any such sublicense that such Sublicensee agrees to be
bound by all terms of this Agreement   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   59


applicable to the
Commercialization of Royalty-Bearing Products in the Royalty-Bearing Territory
(including, without limitation, Article 7); (c) GSK shall provide
written notice to SYNTA of any such proposed sublicense at least [***] days
prior to such execution and provide material terms or redacted copies, at GSKs
option, to SYNTA of each such sublicense within [***] days of its execution; (d) if
GSK grants a sublicense to a Sublicensee, GSK shall be deemed to have
guaranteed that such Sublicensee will fulfill all of GSKs obligations under
this Agreement applicable to the subject matter of such sublicense; (e) GSK
shall not be relieved of its obligations pursuant to this Agreement as a result
of such sublicense.  For the avoidance of
doubt, GSK shall not be required to obtain approval of SYNTA with respect to
sublicenses granted to its Affiliates, or sub-contracting out its Manufacturing
activities in the Territory.  8.3           No
Other Rights.  GSK shall
have no rights to use or otherwise exploit SYNTA Technology or SYNTA Patent
Rights, and SYNTA shall have no rights to use or otherwise exploit GSK
Technology or GSK Patent Rights, in each case, except as expressly set forth
herein.  8.4           Exclusivity.  8.4.1        SYNTA.  During the Term of this Agreement, SYNTA
shall not, and shall cause each of its Affiliates to not, conduct any activity,
either on its own, or with, for the benefit of, or sponsored by any Third
Party, that is designed to develop or commercialize, or grant any license or
other rights to any Third Party to utilize any Technology or Patent Rights
Controlled by SYNTA or GSK, or any of their Affiliates for the express purpose
of developing or commercializing any [***] or [***] except hereunder in the
Development Program, or the Development or Commercialization of Products and in
connection with the conduct of any Permitted Transactions.  8.4.2        GSK.
During
the Term of this Agreement,  GSK shall
not, and shall cause each of its Affiliates to not, conduct any activity,
either on its own, or with, for the benefit of, or sponsored by any Third
Party, that is designed to develop or commercialize, or grant any license or
other rights to any Third Party to utilize any Technology or Patent Rights
Controlled by GSK or SYNTA or any of their Affiliates for the express purpose
of  developing or commercializing any
[***] or [***] except hereunder in the Development Program or the Development
or Commercialization of Products and in connection with the conduct of any
Permitted Transactions.  8.4.3        Permitted Transactions.  If either Party enters into an agreement for
a Permitted Transaction, all Technology and Patent Rights granted to such Party
under the Permitted Transaction shall be included without further action in the
licenses granted to the other Party by Section 8.1.1 or 8.1.2.  8.4.4        Exceptions to Exclusivity.  Notwithstanding Sections 8.4.1 through 8.4.3,
and subject to Sections 1.131(d)(ii) and 1.52(g), the Parties agree that
GSK shall have the exclusive right, but not the obligation, to Develop pursuant
to this Agreement, [***] or [***] that are not, as of the Effective Date,
[***].  At any time during the Term of
the Agreement,GSK may inform the
JDC of its interest in Developing a [***] or a [***], and may request from     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   60


SYNTA all
material data and other relevant information Controlled by SYNTA reasonably
required for GSK to make a determination to Develop such [***] or [***], which
SYNTA will promptly provide to GSK. GSK shall have [***] days to review
such data and information and inform the JDC of its intention to progress
Development of such [***] or [***] following the approval of same by the
JDC.  If the Parties agree to conduct
such Development on such [***] or [***], then such [***] or [***] will
thereafter be deemed a [***] for purposes of this Agreement, including for
purposes of all payment provisions in this Agreement, the provisions of
Sections 8.4.1 through 8.4.3 shall not apply to such [***] or [***] and the
license grants to GSK under Section 8.1.1 and SYNTA under Section 8.1.2
shall automatically be expanded to include Patent Rights and Technology
Controlled by SYNTA and/or GSK related to the making, having made, using,
selling, offering for sale and importing such [***] or [***], including the
[***] or [***], as applicable.  8.5           Standstill
Agreement.  (a)           Standstill
Obligation.  Except as permitted by Section 8.5(b) or
Section 8.5(c), during the [***] ([***]) years after the Effective Date of
this Agreement, without the prior written consent of the Board of Directors of
SYNTA, GSKand its Affiliates will
not (and will not assist or encourage others to) directly or indirectly in any
manner: (i) acquire, announce an intention to acquire, or agree to acquire,
directly or indirectly, alone or in concert with others, by purchase, gift or
otherwise, any direct or indirect beneficial ownership (within the meaning of Rule 13d-3
under the Exchange Act) or interest in any securities or direct or indirect
rights, warrants or options to acquire, or securities convertible into or
exchangeable for, any securities of SYNTA; (ii) make, or in any way
participate in, directly or indirectly, alone or in concert with others, any solicitation
of proxies to vote (as such terms are used in the proxy rules of the SEC
promulgated pursuant to Section 14 of the Exchange Act) any securities of
SYNTA with respect to any business combination, restructuring, recapitalization
or similar transaction; (iii) form, join or in any way participate in a group
within the meaning of Section 13(d)(3) of the Exchange Act with
respect to any voting securities of SYNTA; (iv) acquire, announce an
intention to acquire, or agree to acquire, directly or indirectly, alone or in
concert with others, by purchase, exchange or otherwise, (v) any of the
assets, tangible or intangible, of SYNTA or (vi) direct or indirect
rights, warrants or options to acquire any assets of SYNTA, other than in the
ordinary course of business; (vii) enter into any arrangement or
understanding with others to do any of the actions restricted or prohibited
under clauses (i), (ii), (iii) or (iv) of this Section 8.5(a);
or (viii) otherwise act in concert with others, to seek to offer to SYNTA
or any of its stockholders any business combination, restructuring,
recapitalization or similar transaction to or with SYNTA.  (b)           The provisions of Section 8.5(a) shall
not apply (i) in the event that SYNTA announces publicly that it is
seeking, or considering seeking, purchasers for SYNTA or that it is otherwise
exploring, or considering exploring, strategic options, (ii) upon the
commencement by a Third Party of a tender or exchange offer for more than fifty
percent (50%) of the voting power of the outstanding voting securities of
SYNTA, and (iii) if SYNTA publicly announces a transaction, or an
intention to effect any transaction, which would result in (A) the sale by
SYNTA or one or more of its subsidiaries to a Third Party of assets
representing more than fifty percent (50%) of the consolidated earning power or
assets of SYNTA and its    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   61


subsidiaries, (B) the
common shareholders of SYNTA immediately prior to such transaction owning less
than fifty percent (50%) of the outstanding common stock of the acquiring
entity or, in the case of a merger transaction, the surviving corporation (or,
if the surviving corporation is a subsidiary of a parent company, the parent
company) or (C) a Third Party acquiring beneficial ownership of more than
[***] percent ([***]%) of the outstanding common stock of SYNTA. For purposes
of clarity, the foregoing provisions shall prohibit GSK from acquiring shares
of SYNTA Common Stock pursuant to a public tender offer for all outstanding
SYNTA Common Stock in consideration for cash unless one of the exceptions in
the preceding sentence applies.  (c)           Nothing in Section 8.5(a) or
otherwise in the Agreement shall prevent GSK or its Affiliates (or in the case
of Section 8.5(c)(iv) their employees) from (i) making an offer
to SYNTA to acquire SYNTAs rights to Collaboration Compounds and/or Products, (ii) purchasing
the shares of Common Stock as contemplated by this Agreement or the Stock
Purchase Agreement, (iii) acquiring securities of SYNTA issued in
connection with distributions, stock splits or recapitalizations and the like, (iv) purchasing
securities of SYNTA for (A) a pension plan established for the benefit of
employees of GSK or its Affiliates, (B) any employee benefit plan of GSK
or its Affiliates, (C) any stock portfolios not controlled by GSK or any
of its Affiliates that invest in SYNTA among other companies, or (D) any
account of an officer, director or employee of GSK or its Affiliates in such
individuals personal capacity, or (v) acquiring securities of another
biotechnology, pharmaceutical or consumer healthcare company that beneficially
owns any of the securities of SYNTA, provided that any securities of SYNTA so
acquired shall be subject to the provisions of Section 8.5(a).  (d)           The provisions of
this Section 8.5 shall terminate immediately upon a Change of Control of
SYNTA that occurs during the first [***] years after the Effective Date.  9.             INTELLECTUAL
PROPERTY RIGHTS  9.1           SYNTA
Intellectual Property Rights. 
SYNTA shall have sole and exclusive ownership of all right, title and
interest, or exclusive license to, on a worldwide basis in and to any and all
SYNTA Technology and SYNTA Patent Rights.  9.2           GSK
Intellectual Property Rights. 
GSK shall have sole and exclusive ownership of all right, title and
interest on a worldwide basis in and to any and all GSK Technology and GSK
Patent Rights.  9.3           Joint
Technology Rights.  GSK
and SYNTA shall jointly own all Joint Technology and Joint Patent Rights.  Notwithstanding anything to the contrary
contained herein or under Applicable Laws, the Parties hereby agree that either
Party may use or license or sublicense to Affiliates or Third Parties all or
any portion of its interest in Joint Technology, Joint Patent Rights or jointly
owned Confidential Information for any purpose other than the discovery,
development, manufacture, use, sale or importation of Class 1 Covered
Compounds or Class 2 Covered Compounds, subject to Section 8.4.4,
without the prior written consent of the other Party, without restriction and
without the obligation to provide compensation to the other Party.    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   62


9.4           Inventorship.  The JPC shall initially determine
inventorship of Program Technology under U.S. patent law.  In case of a dispute at the JPC over
inventorship and, as a result, whether any particular Technology is SYNTA
Technology, GSK Technology or Joint Technology, such dispute shall be resolved
according to U.S. patent law by patent counsel selected by the JPC and, unless
otherwise agreed by the Parties, who (and whose firm) is not at the time of the
dispute, and was not at any time during the past [***] ([***]) year prior to
such dispute, performing services for either of the Parties, and if such patent
counsel (and firm) have performed services for either Party in the previous
[***] ([***]) years, such Party will inform the other of the nature of such
services.  Expenses of such patent
counsel shall be shared equally by the Parties.  10.          FILING, PROSECUTION AND MAINTENANCE OF PATENT RIGHTS  10.1         Patent
Filing, Prosecution and Maintenance.  10.1.1      SYNTA
Prosecution Rights.Subject
to Section 10.1.3,SYNTA,
acting through patent counsel or agents of its choice, shall be solely
responsible for the preparation, filing, prosecution and maintenance of the
SYNTA Patent Rights and Joint Patent Rights. 
GSK shall cooperate with and assist SYNTA in all reasonable respects, in
connection with SYNTAs preparation, filing, prosecution (including review and
comments regarding responses to office actions and/or official actions from
worldwide patent offices) and maintenance of SYNTA Patent Rights and Joint
Patent Rights.  The costs and expenses
incurred by SYNTA in connection with the preparation, filing, prosecution and
maintenance of SYNTA Patent Rights and Joint Patent Rights with respect to a
Product shall be Development Costs until Commercialization Regulatory Approval
is obtained with respect to such Product, thereafter such costs will be borne
[***] by [***] in the Royalty-Bearing Territory (if the Product covered by such
SYNTA Patent Rights or Joint Patent Rights is a Royalty-Bearing Product in the
Royalty-Bearing Territory) and shall be [***] if the Product covered by such
SYNTA Patent Rights or Joint Patent Rights is a Co-Commercialized Product in
the Co-Commercialization Territory.  10.1.2      GSK
Prosecution Rights.GSK,
acting through patent counsel or agents of its choice, shall be responsible for
the preparation, filing, prosecution and maintenance of all GSK Patent
Rights.  At GSKs request, subject to Section 10.1.3,SYNTA shall cooperate with and assist GSK
in all reasonable respects, in connection with GSKs preparation, filing,
prosecution and maintenance of GSK Patent Rights.  The costs and expenses incurred by GSK in
connection with the preparation, filing, prosecution and maintenance of GSK
Patent Rights with respect to a Product shall be Development Costs until
Commercialization Regulatory Approval is obtained with respect to such Product,
thereafter such costs will be borne [***] by [***] in the Royalty-Bearing
Territory (if the Product covered by such GSK Patent Rights is a
Royalty-Bearing Product in the Royalty-Bearing Territory) and shall be [***] if
the Product covered by such GSK Patent Rights is a Co-Commercialized Product in
the Co-Commercialization Territory.  10.1.3      Information
and Cooperation.  Each
filing Party shall (a) promptly notify the other Party, through the JPC,
of any Program Technology and the JPC shall discuss the filing of any patent
application with respect thereto; (b) regularly provide the other Party
with copies of all patent applications filed hereunder for any Program Technology
and other material    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    63


submissions and
correspondence with the patent offices, in sufficient time to allow for review
and comment by the other Party; provided, that SYNTA shall consider in good
faith all comments of GSK with respect to the SYNTA Patent Rights and shall
include all of GSKs comments with respect to the [***] and [***] unless
otherwise agreed by the JPC; (c) provide the other Party and its patent
counsel with an opportunity to consult with the Party and its patent counsel
regarding the filing and contents of any such application, amendment,
submission or response, and the advice and suggestions of the other Party and
its patent counsel shall be taken into consideration in good faith by such
Party and its patent counsel in connection with such filing; and (d) execute
any documents that may be necessary to perfect the filing Partys rights in and
to any Program Technology and, in the event that the filing Party is unable for
any reason to secure the signature of the other Party to any lawful and
necessary document required to perfect its rights in and to any such Program
Technology, the other Party hereby designates the filing Party as its agent,
and hereby grants to the filing Party a power of attorney with full power of
substitution, which power of attorney shall be deemed coupled with an interest,
for the sole purpose of effecting the foregoing.  Each filing Party shall pursue in good faith
all reasonable claims requested by the other Party in the prosecution of any
Patent Rights under this Section 10.1.  10.1.4      Abandonment.  If either Party decides to cease prosecution
or to allow to lapse any of the Patent Rights covering any Product, such Party
(the Abandoning Party) shall inform the other Party (the Assuming Party) of
such decision promptly and, in any event, so as to provide the Assuming Party a
reasonable amount of time to meet any applicable deadline to establish or
preserve such Patent Rights in such country or region.  The Assuming Party shall have the right to
assume responsibility for continuing the prosecution of such Patent Rights in
such country or region and paying any required fees to maintain such Patent
Rights in such country or region or defending such Patent Rights, all at the Assuming
Partys sole expense, through patent counsel or agents of its choice.  The Assuming Party shall not become an
assignee of any such Patent Rights as a result of its assumption of any such
responsibility.  Upon transfer of the
Abandoning Partys responsibility for filing, prosecuting and maintaining any
of the Patent Rights to the Assuming Party under this Section 10.1.4, the
Abandoning Party shall promptly deliver to the Assuming Party copies of all
necessary files related to the Patent Rights with respect to which
responsibility has been transferred and shall take all actions and execute all
documents reasonably necessary for the Assuming Party to assume such filing,
prosecution and maintenance.  10.2         Legal
Actions.  10.2.1      Third
Party Infringement.  (a)           In General.  (i)            Notice.  In the event either Party becomes aware of (A) any
suspected infringement or misappropriation of 
any SYNTA Patent Rights, Joint Patent Rights, GSK Patent Rights or
Program Technology through the Development or Commercialization of a
Collaboration Compound or Product or (B) the submission by any Third Party
of an abbreviated NDA under the Hatch-Waxman Act for a product comprising a
Collaboration Compound (each, an Infringement), that Party shall promptly
notify the other Party and provide it with all details     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   64


of such Infringement of
which it is aware.  The JPC shall
promptly meet to discuss the Infringement and strategy for enforcement.  (ii)           GSK Right to Enforce.  Unless otherwise determined by the JSC as
part of its consideration of an overall intellectual property strategy for
Patent Rights or Program Technology involving Products, GSK shall have the
first right, but not the obligation, to address such Infringement in the
Territory by taking reasonable steps, which may include the institution of
legal proceedings or other action (an Action), and to compromise or settle
such Action; provided, that: (A)GSK shall keep SYNTA fully informed about such Action and SYNTA shall
provide all reasonable cooperation to GSK in connection with such Action; (B) GSK
shall not take any position with respect to, or compromise or settle, such
Action in any way that is reasonably likely to directly and adversely affect
the scope, validity or enforceability of the SYNTA Patent Rights, Joint Patent
Rights, SYNTA Technology or Joint Technology without the prior consent of
SYNTA, which consent shall not be unreasonably withheld; and (C) if GSK
does not intend to prosecute or defend an Action, or ceases to diligently
pursue such an Action, it shall promptly inform SYNTA in such a manner that
such Action will not be prejudiced and Section 10.2.1(a)(iii) shall
apply.  (iii)SYNTA Right to
Enforce.If (A) GSK informs SYNTA that it does not intend to prosecute an
Action in respect of Joint Patent Rights, SYNTA Patent Rights, Joint Program
Technology or SYNTA Technology, (B) within [***] days after notice of
Infringement GSK has not commenced any such 
Action, or (C) if GSK thereafter ceases diligently to pursue such
Action and only if GSK has not informed SYNTA that it is not proceeding on the
opinion of competent counsel in accordance with Section 2.5.5 (and where
GSK is relying on such opinion, GSK will have a discussion with SYNTA
concerning such opinion to the extent legally permitted to do so), then SYNTA
shall have the right, at its own expense, upon notice to GSK to take
appropriate action to address such Infringement, including by initiating its
own Action or taking over prosecution of any Action initiated by GSK.  In such event, SYNTA shall keep GSK fully
informed about such Action and shall consult with GSK before taking any major
steps during the conduct of such Action. 
GSK shall provide all reasonable cooperation to SYNTA in connection with
such Action.  SYNTA shall not take any
position with respect to, or compromise or settle, such Action in any way that
is reasonably likely to directly and adversely affect the scope, validity or
enforceability of the Joint Patent Rights or Joint Technology without GSKs
prior written consent, which consent shall not be unreasonably withheld.  (b)           Right to
Representation.  Each Party shall
have the right to participate and be represented by counsel that it selects, in
any Action instituted under Section 10.2.1(a)(ii) or (iii) by
the other Party.  If a Party with the
right to initiate an Action under Section 10.2.1(a) to eliminate an
Infringement lacks standing to do so and the other Party has standing to
initiate such Action, then the Party with the right to initiate an Action under
Section 10.2.1(a) may name the other Party as plaintiff in such
Action or may require the Party with standing to initiate such Action at the
expense of the other Party; provided, that if GSK has informed SYNTA that it
would not proceed with such Action on the opinion of competent counsel, SYNTA
may not require GSK to initiate such Action.    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   65


(c)           Cooperation.  In any Action instituted under this Section 10.2.1,
the Parties shall cooperate with and assist each other in all reasonable
respects.  Upon the reasonable request of
the Party instituting such Action, the other Party shall join such Action and
shall be represented using counsel of its own choice, at the requesting Partys
expense; provided, thatif
GSK has informed SYNTA that it would not proceed with such Action on the
opinion of competent counsel, SYNTA may not require GSK to join such Action.  (d)           Allocation of
Proceeds.  (i)            Co-Commercialized Products.  Any amounts recovered by either Party
pursuant to Actions under Section 10.2.1(a)(ii) or (iii) with
respect to any Infringement through the Development or Commercialization of a
Product or Collaboration Compound in the Co-Commercialization Territory prior
to the exercise by SYNTA of its Commercialization Opt-Out Right, whether by
settlement or judgment, shall be allocated in the following order: (A) first,
to reimburse GSK and SYNTA for their reasonable out-of-pocket expenses in
making such recovery (which amounts shall be allocated pro rata if insufficient
to cover the totality of such expenses); and (B) then, to GSK and SYNTA
[***] as the [***] and [***].  (ii)           Royalty-Bearing Products.  Any amounts recovered by either Party
pursuant to Actions under Sections 10.2.1(a)(ii) or (iii) with
respect to any Infringement through the Development or Commercialization of a
Product or Collaboration Compound in the ROW Territory or in the U.S. Territory
on and after the date of exercise by SYNTA of its Commercialization Opt-Out
Right, whether by settlement or judgment, shall be allocated in the following
order: (A) first, to reimburse GSK and SYNTA for their reasonable
out-of-pocket expenses in making such recovery (which amounts shall be
allocated pro rata if insufficient to cover the totality of such expenses); and
(B) then, to GSK and SYNTA [***] as [***] on [***] of the [***] by the
[***] to [***] to [***] in respect of such [***], in each case as determined by
the JSC in good faith.  10.2.2Orange Book; Patent Registry.After completion of the activities
contemplated by the Regulatory Filings Transfer Plan, GSKwill have soledecision-making authority with respect to the determination of whether
or not to submit SYNTA Patent Rights, Joint Patent Rights or GSK Patent Rights
to the applicable regulatory authorities for listing in the Orange Book as
required under the Hatch-Waxman Act.  In
furtherance of this responsibility, SYNTA will permit GSK, within [***] days
after the Effective Date, to audit the SYNTA Patent Rights to ensure that such
SYNTA Patent Rights satisfy GSKs internal standards for determining, among
other things, validity of such SYNTA Patent Rights and lack of fraud on any
patent offices in the Territory.  In
addition to the foregoing, GSK shall have sole decision-making authority with
respect to Patent Rights to be listed on the Canadian Patent Registry.  10.2.3      Defense
of Claims.  In the event
that any action, suit or proceeding is brought against either Party or an
Affiliate or Sublicensee of either Party alleging the infringement of the
Technology or Patent Rights of a Third Party by the Development or
Commercialization, including, without limitation, the Manufacture, use or sale,
of any Product or Collaboration Compound, such Party shall notify the other
Party within [***] days of the earlier     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   66


of (a) receipt of
service of process in such action, suit or proceeding, or (b) the date
such Party becomes aware that such action, suit or proceeding has been
instituted and the JPC shall meet as soon as possible to discuss the overall
strategy for defense of such matter.  GSK
shall have the right, but not the obligation, to defend such action, suit or
proceeding in the Territory.  SYNTA or
its Affiliates or Sublicensees shall have the right to separate counsel at its
or their own expense in any such action, suit or proceeding, and the Parties
shall cooperate with each other in all reasonable respects in any such action,
suit or proceeding.  If SYNTA has not
exercised its Commercialization Opt-Out Right, all such expenses with respect
to any such action, suit or proceeding in the Co-Commercialization Territory
shall be Commercialization Expenses and all such expenses in the U.S. Territory
if SYNTA exercises its Commercialization Opt-Out Right and the ROW Territory
shall be borne solely by GSK.  Each Party
shall promptly furnish the other Party with a copy of each communication
relating to the alleged infringement that is received by such Party including
all documents filed in any litigation. 
In no event shall either Party settle or otherwise resolve any such
action, suit or proceeding brought against the other Party or any of its
Affiliates or Sublicensees without the other Partys prior written consent.  10.3         Trademarks,
Logos, Etc.  10.3.1Determination
of Trademarks, Logos, Etc.The Product Trademark(s), trade dress, logos,
slogans, designs and copyrights used on and in connection with the
Co-Commercialized Products under which each Co-Commercialized Product shall be
marketed in the Co-Commercialization Territory (such Product Trademarks
hereinafter referred to as the Co-Commercialization Trademarks) shall be
developed by the Parties and reviewed and approved by the JCC.GSK shall be responsible for
developing and selecting all other Product Trademarks applicable to Royalty-Bearing
Products in the Territory.  To the extent
possible, the same Product Trademark(s) will be used throughout the
Territory.  GSK shall own all trade
dress, logos, slogans, designs and copyrights described above.  10.3.2      Registration,
Maintenance, Enforcement and Defense.  GSK shall be responsible for the registration
of the Product Trademark(s) to be used with Royalty-Bearing Products in
the Royalty-Bearing Territory and the Co-Commercialization Trademarks, and
shall be the exclusive owner of all Product Trademarks, including the
Co-Commercialization Trademarks throughout the Territory, and any domain names
incorporating such Product Trademarks, and all goodwill associated
therewith.  GSK shall take all such
actions as are required to continue and maintain in full force and effect and
enforce and defend all Product Trademarks and registrations thereof, including
the Co-Commercialization Trademarks, against infringement and misappropriation
in the Territory, and shall be solely responsible for all expenses incurred in
connection therewith, which shall be Commercialization Expenses to the extent
they relate to a Co-Commercialization Trademark.  The Parties shall conduct the Promotional
Efforts for each Co-Commercialized Product in the Co-Commercialization Territory
exclusively under the Co-Commercialization Trademarks.  GSK shall consult with SYNTA with respect to
material matters relating to the Co-Commercialization Trademarks, including any
misappropriation or infringement thereof, and consider SYNTAs input in good
faith and shall provide SYNTA with updates on material issues associated with
Product Trademarks in the Territory as reasonably requested by SYNTA, but not
more frequently than annually.    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    67


10.3.3      Use
of Trademark.  In primary
and secondary packages and labels and all marketing and promotional literature
relating to Products, SYNTA shall be presented and described as the Party from
whom GSK licensed the Product and, to the extent practicable, the SYNTA name
and logo shall appear in the same in size and prominence as the GSK name and
logo on all Product primary and secondary packages and labels and all marketing
and promotional literature used in the Territory, unless prohibited by
Applicable Laws.  10.3.4      Licenses.  SYNTA shall grant to GSKthe non-exclusive, royalty-freeright to
use the SYNTA name and corporate logo (SYNTAs Brand) in the Territory solely
for the purpose of GSKs Commercialization of the Product in accordance with
the terms of this Agreementand GSK shall grant to SYNTA(a) an exclusive
(except as to GSK), royalty-free license to use Co-Commercialization Trademark(s) in
the Co-Commercialization Territory and (b) the non-exclusive, royalty-free
right to use the GSK name and corporate logo (GSKs Brand) in the
Co-Commercialization Territory in each case solely for the conduct of SYNTA
Co-Commercialization Activities for the Co-Commercialized Product so long as
SYNTA does not exercise its Commercialization Opt-Out Right.  Except as provided herein, neither Party
shall have any rights in or to the other Partys name or corporate logo or the
goodwill pertaining thereto.  SYNTA
hereby acknowledges GSKs exclusive right, title and interest in and to GSKs
Product Trademark(s), including the Co-Commercialization Trademarks and GSKs
Brand and agrees that neither it nor its Affiliates will at any time do, or
cause to be done, any act or thing contesting or in any way intending to impair
the validity of and/or GSKs exclusive right, title and interest in and to GSKs
Product Trademark(s) and GSKs Brand. 
SYNTA shall not in any manner represent that it owns the Product
Trademarks, including the Co-Commercialization Trademarks or GSKs Brand, and
SYNTA hereby acknowledges that use of the Co-Commercialization Trademarks and
GSKs Brand shall not create any rights, title or interest in or to the same in
SYNTAs favor, but that all such use shall inure to the benefit of GSK.  GSK hereby acknowledges SYNTAs exclusive
right, title and interest in and to SYNTAs Brand and agrees that neither it
nor its Affiliates will at any time do, or cause to be done, any act or thing
contesting or in any way intending to impair the validity of and/or SYNTAs
exclusive right, title and interest in and to SYNTAs Brand.  GSK shall not in any manner represent that it
owns the SYNTA Brand, and GSK hereby acknowledges that use of SYNTAs Brand
shall not create any rights, title or interest in or to the same in GSKs
favor, but that all such use shall inure to the benefit of SYNTA.  11.          TERM AND TERMINATION  11.1Term.This Agreement shall commence
on the Effective Date and shall continue in full force and effect, unless
otherwise terminated pursuant to Section 11.2, (a) in the U.S.
Territory, if SYNTA has not exercised its Commercialization Opt-Out Right with
respect to a Co-Commercialized Product, for as long as such Co-Commercialized
Product is being sold by either Party in the Co-Commercialization Territory
and, if SYNTA has exercised its Commercialization Opt-Out Right with respect to
a Product, until the expiration of the applicable Royalty Term with respect to
such Product and (b) in the ROW Territory, until the expiration of all
applicable Royalty Terms with respect to Royalty-Bearing Products(the Term).
Upon the    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   68


expiration of this Agreement
as set forth in this Section 11.1, the license rights granted to GSK
hereunder shall be converted to perpetual and fully paid-up licenses.  11.2         Termination.  Subject to Section 14.1(d), this
Agreement may be terminated by either Party as follows:  11.2.1      Unilateral
Right to Terminate Agreement.  (a)           GSK Rights to
Terminate.  (i)            Termination
of Agreement. GSK shall have the
right to terminate this Agreement in its entirety at any time after the
Effective Date by providing [***] prior written notice to SYNTA at any time
prior to the date of First Commercial Sale of a Product and [***] prior written
notice at any time on and after the date of First Commercial Sale of a Product.  Upon delivery of termination notice by GSK,
GSK shall not be obligated to initiate any new Clinical Trials or
non-clinical studies, make any further filings for Regulatory Approval or
Commercialization Regulatory Approval, or launch the Product in any further
countries in order to meet its obligations to use Commercially Reasonable
Efforts with respect to the Collaboration Compounds and Products pursuant to
the terms of this Agreement as of the date on which GSK delivered its
termination notice as set forth above.  (ii)Termination in
Selected Regions.  In the
event that GSK reasonably determines, in its sole discretion, that the
Commercialization of all Products in a Region is not commercially viable or
feasible, it shall provide [***] written notice to SYNTA at any time prior to
the date of First Commercial Sale and [***] written notice at any time on and
after the date of First Commercial Sale, which shall set forth in reasonable
detail its written justification for, and supporting evidence with respect to,
such determination.For purposes of this Section 11.2.1(a)(ii), Region
shall mean either (A) [***], (B) [***], or (C) the [***] if GSK
opts not to Commercialize a Product in at least [***] of the [***].  (iii)Termination for
Safety Reasons.  GSK may terminate this Agreement immediately upon written notice
following the withdrawal of Product from any market as a result of bona fide
concerns that the Product is unsafe for administration to humans (a Valid
Safety Issue).  For the avoidance of
doubt, the [***] notice period applicable to termination under Sections
11.2.1(a)(i) and (ii) shall not apply in the case of termination for
a Valid Safety Issue.  (b)           SYNTA Right to
Terminate.  Except to the extent the
following is unenforceable under the Applicable Laws of a particular jurisdiction
where a patent application within the SYNTA Patent Rights is pending or a
patent within the SYNTA Patent Rights is issued, SYNTA may terminate this
Agreement immediately upon written notice to GSK in the event that GSK or any
of its Affiliates or Sublicensees Challenges any SYNTA Patent Right or assists
a Third Party in initiating a Challenge of any SYNTA Patent Right.  11.2.2      Termination
for Breach.  Except as set
forth herein, either Party may terminate this Agreement, effective immediately
upon written notice to the other Party for a material breach by the other Party
of any term of this Agreement that remains uncured [***]    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   69


days ([***] days in the
event that the breach is a failure of a Party to make any payment required
hereunder) after the non-breaching Party first gives written notice to the
other Party of such breach (providing detail regarding such breach) and its
intent to terminate this Agreement if such breach is not cured; provided, that (a) the
[***] day cure period may be extended for a period not to exceed [***] days if
the JSC unanimously determines that the breaching party is in the process of
attempting in good faith to cure such breach and (b) in the event the
breaching Party disputes in good faith the existence of the breach, including a
payment breach, the obligation of such Party to cure shall be stayed pending
resolution of such dispute.  11.2.3      Termination
for Insolvency.  In the
event that either Party makes an assignment for the benefit of creditors,
appoints or suffers appointment of a receiver or trustee over all or
substantially all of its property, files a petition under any bankruptcy or
insolvency act or has any such petition filed against it which is not
discharged within [***] days of the filing thereof, then the other Party may
terminate this Agreement effective immediately upon written notice to such
Party.  In connection therewith, all
rights and licenses granted under this Agreement are, and shall be deemed to
be, for purposes of Section 365(n) of the United States Bankruptcy
Code, licenses of rights to intellectual property as defined under Section 101(56)
of the United States Bankruptcy Code.  11.3         Consequences
of Termination of Agreement. 
In the event of the termination of this Agreement pursuant to Section 11.2,
the following provisions shall apply, as applicable.  11.3.1      Termination
by SYNTA under 11.2.1(b), 11.2.2 or 11.2.3 or by GSK under Section 11.2.1(a)(i).  If this Agreement is terminated by GSK
pursuant to Section 11.2.1(a)(i) or by SYNTA pursuant to Section 11.2.1(b),  11.2.2 or 11.2.3:  (a)           All licenses and
rights granted to GSK under this Agreement shall immediately terminate and
SYNTA shall no longer be subject to any obligations under Section 8.4.1.  (b)           SYNTA shall
have an exclusive, perpetual license, with the right to sublicense, under the
GSK Patent Rights, GSK Technology, Product Trademarksother than
Product Trademarks incorporating the GSK Brand, and GSKs rights to Joint Patent Rights and Joint Technology directly
related to, and used by GSK with respect to the Development and/or
Commercialization of, any Product as of the effective date of termination,
solely for the purpose of making, using, selling, offering for sale and
importing such Product throughout the Territory; provided, that if this
Agreement is terminated by GSK pursuant to Section 11.2.1(a)(i) or by
SYNTA pursuant to Section 11.2.2 or 11.2.3, (i) SYNTA will pay GSK a royalty
based on Annual Net Sales of any such Product
that is being actively Developed and/or Commercialized by GSK as of the
effective date of such termination (each, a Reverted Royalty-Bearing Product),
commencing on the date of First Commercial Sale of such Product by SYNTA and
ending upon the last day of the applicable Royalty Term for such Reverted
Royalty-Bearing Product, at a rate equal to the
Applicable Reversion Royalty Rate, and (ii) the remaining terms of
Sections 6.5.1(c), 6.6, 6.7, 6.8, 6.9 and 6.10 shall apply mutatis mutandis to each such Reverted
Royalty-Bearing Product.  For purposes of this Section 11.3.1(b),
the term Applicable Reversion Royalty Rate means, on a country-by-country
basis, (a) if this Agreement is terminated by GSK pursuant to Section 11.2.1(a)(i),
(i) [***] percent ([***]%) if, as of the   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   70


effective
date of termination, there has not been a Drug Approval Application filed for
such Reverted Royalty-Bearing Product; (ii)[***] percent ([***]%) if, as of the effective date of termination, there has
been a Drug Approval Application filed for such Reverted Royalty-Bearing
Product; and (iii) [***] percent ([***]%) if, as of the effective date of termination, a Commercialization Regulatory
Approval has been received for such Reverted Royalty-Bearing Product or the
First Commercial Sale of such Reverted Royalty-Bearing Product has occurred;
and (b) if this Agreement is terminated by SYNTA pursuant to Section 11.2.2
or 11.2.3, on a country-by-country basis (i) [***] percent ([***]%) if, as of the effective date of termination, there has
not been a Drug Approval Application filed for such Reverted Royalty-Bearing
Product; (ii) [***] percent ([***]%) if, as of the effective date of termination, there has been a Drug Approval
Application filed for such Reverted Royalty-Bearing Product; and (iii) [***]
percent ([***]%) if, as of the effective date
of termination, a Commercialization Regulatory Approval has been received for
such Reverted Royalty-Bearing Product or the First Commercial Sale of such
Reverted Royalty-Bearing Product has occurred.  (c)           Each Party shall
promptly return all Confidential Information of the other Party that is not
subject to a continuing license hereunder; provided, that, each Party may
retain one copy of the Confidential Information of the other Party in its
archives solely for the purpose of establishing the contents thereof and
ensuring compliance with its obligations hereunder.  (d)           Upon request of
SYNTA, which shall be provided to GSK within [***] days of the date on which
the applicable Party delivers its termination notice, GSK shall promptly, and
in any event within [***] days after SYNTAs request (which request may specify
any or all of the actions in clauses (i) through (x)): (i) transfer
to SYNTA all of its right, title and interest in all Regulatory Filings, Drug
Approval Applications and Regulatory Approvals then in its name applicable to
Products, if any; (ii) notify the applicable Regulatory Authorities and
take any other action reasonably necessary to effect such transfer; (iii) provide
SYNTA with copies of all material correspondence between GSK and such
Regulatory Authorities relating to such Regulatory Filings, Drug Approval
Applications and Regulatory Approvals; (iv) unless expressly prohibited by
any Regulatory Authority, transfer sponsorship and control to SYNTA of all
Clinical Trials of Products being conducted as of the effective date of
termination and continue to conduct such trials after the effective date of
termination to enable such transfer to be completed without interruption of any
such trial for such mutually agreed reasonable period of time, at [***]; (v) cooperate
with SYNTA, cause its Affiliates to cooperate with SYNTA and use Commercially
Reasonable Efforts to require any Third Party with which GSK has an agreement
with respect to the conduct of Clinical Trials for Products or the Manufacture
of Products (including, without limitation, agreements with contract
manufacturing organizations, contract research organizations, clinical sites
and investigators), to cooperate with SYNTA in order to accomplish the transfer
to SYNTA of similar rights as held by GSK under its agreements with such Third
Parties; (vi) provide SYNTA, at the [***], with all supplies of
Collaboration Compounds and Products in the possession of GSK or any Affiliate
or contractor of GSK; (vii) provide SYNTA with copies of all material
reports and material data generated or obtained by GSK or its Affiliates,
subject to any confidentiality obligations to Third Parties, pursuant to this
Agreement that relate to any Product that have not previously been provided to
SYNTA; and (viii) grant to SYNTA the right to use and disclose in
connection with the Development and Commercialization of Products all GSK
Confidential Information Controlled by GSK that is     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   71


necessary
for, and relates directly to, the Development and Commercialization of Products
as such Products were being Developed or Commercialized hereunder as of the
effective date of termination of this Agreement and agree that all such GSK
Confidential Information shall be subject to clause (i) of the second
sentence of Section 7.1.1 as if it were SYNTA Confidential Information but
shall not be subject to clause (ii) of the second sentence of Section 7.1.1,
(ix) if GSK has Manufactured, is Manufacturing or is having manufactured
such Product or any intermediate of such Product as of the date of termination,
(A)transfer copies of all documents and materials Controlled byGSKand embodyingGSKTechnology
and/orGSKPatent Rights that are at the time ofsuch terminationbeing used byGSKor its Third
Party manufacturers to Manufacture a Collaboration Compound or Product, including but
not limited to all suppliers, analytical methods, quality standards,
specifications,commercial API formula, process chemistry,
Manufacturing process descriptions, process flows, cycle times, process
parameters, process equipment type and sizes, cleaning methods,commercial API
samples, master safety data sheets, and stability reports (the GSKManufacturing
Know-How) solely to enable the Manufacture of a Collaboration Compound orProductbySYNTA, its
Affiliates or any Third Party manufacturer of SYNTA; (B) promptly make
available to SYNTA or any suchThird Partymanufacturer a
reasonable number of appropriately trained personnel to provide, [***], on a
mutually convenient timetable, technical assistance in the transfer of GSK
Manufacturing Know-How to SYNTA; (C) cooperate with SYNTA, cause its
Affiliates to cooperate with SYNTA and use Commercially Reasonable Efforts to
require its Third Party manufacturers of a Collaboration Compound or Product to
cooperate with SYNTA in order to accomplish the transfer to SYNTA of similar
rights as held by GSK under its Third Party manufacturer agreements; and (D) solely
in the event that such Third Party manufacturers do not agree to such transfer
of rights to SYNTA referred to in 11.3.1(d)(ix)(C), or GSK is Manufacturing
Product or API and/or intermediate in its own facilities at the effective date
of termination, supply SYNTA with its requirements of such Product or
intermediate for up to [***] months following such termination at a transfer
price equal to the Manufacturing Cost plus [***] percent ([***]%) for the
supply of such Product or intermediate; and (x) enter into negotiations
with SYNTA and agree upon and implement a plan for the orderly transition of
Development and Commercialization from GSK to SYNTA in a manner consistent with
Applicable Laws and standards of ethical conduct of human Clinical Trials and will
seek to replace all GSK personnel engaged in any Development or
Commercialization activities, in each case, as promptly as practicable.  (e)           If GSK delivers notice of termination
pursuant to Section 11.2.1(a)(i), or SYNTA delivers notice of termination
pursuant to Section 11.2.2, in either case prior to Completion of the
Ongoing Clinical Trial, then during the period
commencing on the date of such notice and continuing until the Completion of
the Ongoing Clinical Trial, GSK shall be required to observe its obligations
hereunder regarding certain milestones and other payments, as described in this
Section 11.3.1(e):  (i)GSK shall
make [***] equivalent to the [***] for the following [***] to the extent they
have not been [***] previously:(A) [***] for [***] in
the [***] of [***] as [***] in [***], (B) [***]of [***], (C) [***] of
[***] in a [***], and (D) [***] of [***] of [***] and [***].    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   72


(ii)           If the total budget for the Ongoing
Clinical Trial as set forth in the initial Global Development Plan (which the
Parties acknowledge is $[***] as of the Execution Date) is exceeded, then GSK
shall pay its share of the overage in accordance with Section 1.54;
provided, that GSK shall not be required to pay
for any overage due to any changes to the Ongoing Clinical Trial as SYNTA may
request or deem necessary after the date on which GSK delivered its termination
notice.  (iii)          GSK
shall make any True-Up Operating Income Payment as described in Section 5
of Schedule 4 based on Commercialization Expenses incurred through
Completion of the Ongoing Clinical Trial to the extent applicable.  11.3.2      Termination
by GSK.  If this Agreement
is terminated by GSK pursuant to Section 11.2.2 or 11.2.3:  (a)           All licenses granted
by SYNTA to GSK pursuant to Section 8.1.1 (including any additional
licenses required to Manufacture API), shall survive the termination in each
case subject to GSKs continued payment of certain milestones related to the
Ongoing Clinical Trial (as further described below) and royalty paymentsunder and in accordance with this
Agreement with respect thereto.  (b)           SYNTA shall grant to
GSK the right to use and disclose in connection with the Development and
Commercialization of Products all SYNTA Confidential Information Controlled by
SYNTA that is necessary for, and relates directly to, the Development and
Commercialization of Products as such Products were being Developed or
Commercialized hereunder as of the effective date of termination of this
Agreement and the Parties agree that all such SYNTA Confidential Information
shall be subject to clause (i) of the second sentence of Section 7.1.1
as if it were GSK Confidential Information but shall not be subject to clause (ii) of
the second sentence of Section 7.1.1.  (c)           All licenses granted
by GSK to SYNTA pursuant to Section 8.1.2 shall terminate, and in the case
of termination by GSK pursuant to Section 11.2.2, SYNTA shall continue to
be subject to the obligations set forth in Section 8.4.1 for [***]
following such termination.  (d)           SYNTAs rights to
conduct SYNTA Co-Commercialization Activities for the Co-Commercialized Product
under Section 5.1.1(a) and/or under any Co-Commercialization
Agreement shall terminate and all Co-Commercialized Products shall thereafter
become Royalty-Bearing Products.  (e)           Each Party shall
promptly return all Confidential Information of the other Party that is not
subject to a continuing license hereunder; provided, that, each Party may
retain one copy of the Confidential Information of the other Party in its
archives solely for the purpose of establishing the contents thereof and
ensuring compliance with its obligations hereunder.  (f)            If GSK delivers notice of
termination pursuant to either Section 11.2.2 or 11.2.3 prior to
Completion of the Ongoing Clinical Trial, then during the period    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   73


commencing
on the date of such notice and continuing until the Completion of the Ongoing
Clinical Trial, GSK shall be required to observe its obligations hereunder
regarding certain milestones and other payments, as described in this Section 11.3.2(f):  (i)            GSK
shall make a [***] equivalent to an appropriate [***] of the following [***] to
the extent they have not been [***]
previously, such [***] to be negotiated by the Parties in good faith:(A) [***]
for [***] in the [***] of [***] as [***] in [***],(B) [***] of [***], (C) [***]
of [***] in a [***], and (D) [***] of [***] of [***] and [***].  (ii)           If the total budget for the Ongoing
Clinical Trial as set forth in the initial Global Development Plan (which the
Parties acknowledge is $[***] as of the Execution Date) is exceeded, then GSK
shall pay its share of the overage in accordance with Section 1.54;
provided, that GSK shall not be required to pay
for any overage due to any changes to the Ongoing Clinical Trial as SYNTA may
request or deem necessary after the date on which GSK delivered its termination
notice.  (iii)          GSK
shall make any True-Up Operating Income Payment as described in Section 5
of Schedule 4 based on Commercialization Expenses incurred through
Completion of the Ongoing Clinical Trial to the extent applicable.  11.3.3      Termination
by GSK of Selected Regions. 
If GSK terminates its rights and obligations under this Agreement with
respect to all Products in a Region as described in Section 11.2.1(a)(ii),
then such Region shall, without any further action of either Party, be removed
from the Territory for purposes of all such Products.  In such event: (a) the licenses granted
to GSK under Article 8 to Commercialize such Products in the Region shall
immediately terminate; (b) the licenses granted to SYNTA under Article 8
to Commercialize such Products in the Region shall continue and survive;
provided, that, (i) such license shall thereafter be exclusive (even as to
GSK) as to the Products that are the subject of the termination, and shall
include the right to grant sublicenses; (ii) SYNTA
will pay GSK a royalty based on Annual Net Sales of any Reverted Royalty-Bearing Products that are being
Developed and/or Commercialized by GSK in such Region as of the effective date
of such termination commencing on the First Commercial Sale by SYNTA and
ending upon the last day of the applicable Royalty Terms for such Reverted
Royalty-Bearing Products, at a rate equal to
the Applicable Reversion Royalty Rate and (iii) the remaining terms
of Sections 6.5.1(c), 6.6, 6.7, 6.8, 6.9 and 6.10 shall apply mutatis mutandis to each such Reverted
Royalty-Bearing Product; (c) upon request of SYNTA (which request may
specify any or all of the actions in clauses (i) through (iv) below),
GSK shall promptly, and in any event within [***] days after SYNTAs request,
which shall be made within the applicable notice period prior to the effective
date of termination: (i) provide SYNTA with a right of access, a right of
reference, and a right to use and incorporate all data, results and information
in all Regulatory Filings and Regulatory Approvals then in its name applicable
to the Commercialization of such Products in any such Region and all material aspects
of Confidential Information Controlled by it as of the date such Region is
removed from the Territory relating to such Regulatory Filings and Regulatory
Approvals for SYNTA to use to seek Regulatory Approvals in such Region; (ii) provide
SYNTA with copies of all correspondence between GSK and such Regulatory
Authorities relating to such Regulatory Filings and Regulatory Approvals; (iii) assign
to SYNTA all agreements between GSK and any     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   74


Third Party with respect to
the conduct of Clinical Trials for such Products in the Region, including,
without limitation, agreements or contracts with contract research
organizations, clinical sites and investigators, unless expressly prohibited by
any such agreement; and (iv) provide SYNTA with copies of all reports and
data obtained by GSK or its Affiliates pursuant to this Agreement that relate
to the Commercialization of such Products in any such Region; (v) if GSK
has Manufactured, is Manufacturing or is having Manufactured such Products or
any intermediate of such Products as of the date such Region is removed from
the Territory, upon the request of SYNTA, GSK shall supply SYNTA with its
requirements of such Products or intermediate for up to [***] months following
such removal at a transfer price equal to GSKs Manufacturing Cost plus [***]
percent ([***]%) for the supply of such Products or intermediate and thereafter
at commercially reasonable terms to be negotiated in good faith between the
Parties and (vi) GSK shall transition the
GSK Co-Commercialization Activities to SYNTA, if applicable; provided,
that SYNTA agrees that certain GSK Co-Commercialization Activities must be
transitioned [***] as follows: (A) [***] of the Products must be
transitioned with management of [***], [***] (for both [***] and [***]) and
[***], and (B) market [***] must be transitioned with [***] and [***];
provided, that if GSK is [***] the Products or providing any other GSK
Co-Commercialization Activities as of the date of termination notice, then GSK
may, at SYNTAs request and for a period not to exceed [***] months from the
effective date of termination, continue such [***] activities or such other GSK
Co-Commercialization Activities at cost.  For purposes of this Section 11.3.3, the
term Applicable Reversion Royalty Rate means, on a country-by-country basis
(1) [***] percent ([***]%) if, as of the
effective date of termination, there has not been a Drug Approval Application
filed for a particular Reverted Royalty-Bearing Product in such country in the
terminated Region; (2) [***] percent ([***]%) if, as of the effective date of termination, there has
been a Drug Approval Application filed for a particular Reverted
Royalty-Bearing Product in such country in the terminated Region; and (3) [***]
percent ([***]%) if, as of the effective date
of termination, a Commercialization Regulatory Approval has been received for a
particular Reverted Royalty-Bearing Product or the First Commercial Sale of
such Reverted Royalty-Bearing Product has occurred, in either case, in such
country in the terminated Region.  11.4         Surviving
Provisions.  Termination
or expiration of this Agreement for any reason shall be without prejudice to:  (a)           Survival of rights
specifically stated in this Agreement to survive;  (b)           The rights and obligations of the
Parties provided in Sections 3.6.2(b), 6.7, 6.8, 6.9, 6.10, 7.1, 8.3, 10.1.1,
10.1.3 (with respect to Joint Patent Rights only), and Articles 1, 9, 11, 13
(except for 13.4) and 14 (including all other Sections or Articles referenced
in any such Section or Article), all of which shall survive such
termination except as provided in this Article 11; and  (c)           any other rights or
remedies provided at law or equity which either Party may otherwise have.    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   75


12.          REPRESENTATIONS, WARRANTIES AND COVENANTS  12.1         Mutual
Representations and Warranties. 
SYNTA and GSK each represents and warrants to the other, as of the
Execution Date, as follows:  12.1.1      Organization.  It is a corporation duly organized, validly existing
and in good standing under the laws of the jurisdiction of its organization,
and has all requisite power and authority, corporate or otherwise, to execute,
deliver and perform this Agreement.  12.1.2      Authorization.  The execution and delivery of this Agreement
and the performance by it of the transactions contemplated hereby have been
duly authorized by all necessary corporate action and will not violate (a) such
Partys certificate of incorporation or bylaws, (b) any agreement,
instrument or contractual obligation to which such Party is bound in any
material respect, (c) any requirement of any Applicable Laws, or (d) any
order, writ, judgment, injunction, decree, determination or award of any court
or governmental agency presently in effect applicable to such Party.  12.1.3      Binding
Agreement.  This Agreement
is a legal, valid and binding obligation of such Party enforceable against it
in accordance with its terms and conditions.  12.1.4      No
Inconsistent Obligation. 
It is not under any obligation, contractual or otherwise, to any Person
that conflicts with or is inconsistent in any respect with the terms of this
Agreement or that would impede the diligent and complete fulfillment of its
obligations hereunder.  12.2         Additional
Representations of SYNTA.  SYNTA further represents and warrants to GSK,
as of the Execution Date, as follows:  12.2.1      Validity
of Patent Rights.  All
SYNTA Patent Rights listed on Schedule 2 are existing and, to SYNTAs
Knowledge, no issued patents which are part of SYNTA Patent Rights listed on Schedule
2 are invalid or unenforceable.  All
SYNTA Patent Rights that (a) contain one or more claims that cover any
Collaboration Compound or Product (including its Manufacture or its formulation
or a method of its delivery or of its use); (b) are necessary for GSK to
exercise the licenses granted to it pursuant to Section 8.1.1, and (c) are
existing on the Execution Date are listed on Schedule 2.  The patent applications included in the SYNTA
Patent Rights have been duly filed.  12.2.2      No Litigation.There are no claims, judgment or
settlements against SYNTA pending, or to SYNTAs Knowledge, threatened, that
invalidate or seek to invalidate the SYNTA Patent Rights.  There is no litigation pending against SYNTA
or any Affiliate of SYNTA that alleges that any of SYNTAs activities relating
to the Collaboration Compounds or Products have violated, or by Developing the
Collaboration Compounds or Products would violate, any of the intellectual
property rights of any Third Party (nor has it received any written
communication threatening such litigation). 
To SYNTAs Knowledge, no litigation has been threatened against SYNTA or
any Affiliate of SYNTA which alleges that any of its activities relating to the
Collaboration Compounds or Products have violated, or by Developing the    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    76


Collaboration Compounds or
Products would violate, any of the intellectual property rights of any Third
Party.  12.2.3      No
Assignment.  SYNTA has not
previously assigned, transferred, conveyed or otherwise encumbered its right,
title and interest in the SYNTA Patent Rights and SYNTA Technology in manner
inconsistent with the terms hereof.  12.2.4      Ownership.  SYNTA is the sole and exclusive owner of, or
solely Controls, the SYNTA Patent Rights, and no other person, corporate or
other private entity, or governmental entity or subdivision thereof, has or
shall have any claim of ownership with respect to the SYNTA Patent Rights.  SYNTA has the right to grant the license
granted to GSK on the terms set forth herein.  12.2.5      Assignment
of Rights.  SYNTA has
obtained the assignment of all interests and all rights of any and all Third
Parties (including but not limited to employees) involved in the creation of
the SYNTA Technology on behalf of SYNTA, and SYNTA has taken reasonable
measures to protect the confidentiality of the SYNTA Technology to the extent
that a failure to do so would have a material adverse effect on GSKs ability
to Develop and Commercialize Products as contemplated by this Agreement.  12.2.6      No
Misappropriation.  To
SYNTAs Knowledge, there is no use, infringement or misappropriation of the
SYNTA Technology in derogation of the rights granted to GSK in this Agreement.  12.2.7      No
Investigations.  To SYNTAs
Knowledge, there are no investigations, inquiries, actions or other proceedings
pending before any Regulatory Authority or other government agency with respect
to the Collaboration Compounds or the Products. 
SYNTA has not received written notice threatening any such investigation,
inquiry, action or other proceeding.  12.2.8      Compliance
with Applicable Laws.  The
Development, testing, Manufacture, labeling, storage, and distribution of the
Collaboration Compounds and Products have been conducted by SYNTA and its
Affiliates and, to SYNTAs Knowledge, its Third Party contractors, in
compliance in all material respects with all Applicable Laws, including with
respect to investigational use, Good Clinical Practices, GLPs, GMPs, record
keeping, security and filing of reports; and neither SYNTA nor its Affiliates,
and to SYNTAs Knowledge, its Third Party contractors, have received any notice
in writing which have led SYNTA to believe that any of the regulatory
submissions relating to the Collaboration Compounds or Products are not currently
in good standing with the FDA.  12.2.9      No
Breach.  SYNTA has
disclosed in writing to GSK all licenses granted to SYNTA by Third Parties with
respect to SYNTA Patent Rights and SYNTA Technology and SYNTA is not in breach
or default under any such agreement and has not received from any licensor any
notice of breach or default.  12.2.10    All
Material Data.  SYNTA has
made available to GSK for its review a complete and accurate record of all
material information and data relating to the results of all     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   77


material
pre-clinical studies and Clinical Trials of Collaboration Compounds or Products
conducted by or on behalf of SYNTA, and all such information and data is
complete and accurate in all material respects.  12.2.11         [***].The Patent Rights and Technology covered by the [***] are not
required to Manufacture or use a Product comprising a Collaboration Compound as
contemplated by this Agreement.  12.3         Additional
Representation of GSK.GSK hereby further represents and
warrants to SYNTA as of the Execution Date that it has not used any SYNTA
Confidential Information or other information provided to GSK by SYNTA to file
or prosecute any patent application covering STA-4783 or the Manufacture or use
thereof at any time prior to the Execution Date.  12.4         Covenants
of GSK.  12.4.1           Internal Policies.GSK shall provide to SYNTA a current copy
of the GSK Internal Policies applicable to the Development and
Commercialization activities ongoing under this Agreement at such time and
shall promptly provide SYNTA with updates to such GSK Internal Policies to the
extent any material changes are made that affect SYNTAs obligations under this
Agreement.  GSK shall be responsible for
its employees adherence to GSK Internal Policies applicable to the Development
and Commercialization of Products under this Agreement.  12.4.2           Patent Application.GSK hereby
covenants that it shall not, during the Term of this Agreement, file or
prosecute any patent application covering STA-4783 or the Manufacture or use
thereof except as provided in this Agreement.  12.5         Covenants
of SYNTA.  12.5.1           Third Party Agreements.  SYNTA shall (a) notify GSK as soon as
reasonably practicable if it intends to terminate a Third Party Agreement, and
the JPC shall promptly discuss and agree on such termination, and (b) at
GSKs written request, grant a sublicense under any Third Party Agreement to
GSK.  12.5.2           Adherence to GSK Policies.  SYNTA shall be responsible for its employees
adherence to GSK Internal Policies applicable the Development and
Commercialization of Products under this Agreement as provided to SYNTA under Section 12.4.1.  13.          INDEMNIFICATION; INSURANCE  13.1         Indemnification
of SYNTA by GSK.  GSK
shall indemnify, defend and hold harmless SYNTA, its Affiliates, their
respective directors, officers, employees and agents, and their respective
successors, heirs and assigns (collectively, the SYNTA Indemnitees), against
all liabilities, damages, losses and expenses (including, without limitation,
reasonable attorneys fees and expenses of litigation) (collectively, Losses)
incurred by or imposed upon the SYNTA Indemnitees, or any of them, as a direct
result of claims, suits, actions, demands or judgments of    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    78


Third Parties, including,
without limitation, personal injury and product liability claims (collectively,
Claims), arising out of the Manufacture, use or sale by GSK or any of its
Affiliates, Sublicensees, distributors or agents of any Product, except with
respect to any Claim or Losses that result from a breach of this Agreement
(including without limitation any representation or warranty made pursuant to Section 12)
by, or the gross negligence or willful misconduct of, SYNTA.  13.2         Indemnification
of GSK by SYNTA.  SYNTA
shall indemnify, defend and hold harmless GSK, its Affiliates, their respective
directors, officers, employees and agents, and their respective successors,
heirs and assigns (collectively, the GSK Indemnitees), against all Losses
incurred by or imposed upon the GSK Indemnitees, or any of them, as a direct
result of Claims arising out of the Manufacture, use or sale by SYNTA or any of
its Affiliates, Sublicensees, distributors or agents of any Product, except
with respect to any Claim or Losses that result from a breach of this Agreement
(including without limitation any representation or warranty made pursuant to Article 12)
by, or the gross negligence or willful misconduct of, GSK.  13.3         Conditions
to Indemnification.  A
Person seeking recovery under this Article 13 (the Indemnified Party) in
respect of a Claim shall give prompt notice of such Claim to the Party from
which indemnification is sought (the Indemnifying Party); provided, that, the
Indemnifying Party is not contesting its obligation under this Article 13,
shall permit the Indemnifying Party to control any litigation relating to such
Claim and the disposition of such Claim; provided, that, the Indemnifying Party
shall (a) act reasonably and in good faith with respect to all matters relating
to the settlement or disposition of such Claim as the settlement or disposition
relates to such Indemnified Party and (b) not settle or otherwise resolve
such claim without the prior written consent of such Indemnified Party (which
consent shall not be unreasonably withheld, conditioned or delayed).  Each Indemnified Party shall cooperate with
the Indemnifying Party in its defense of any such Claim in all reasonable
respects and shall have the right to be present in person or through counsel at
all legal proceedings with respect to such Claim.  13.4         Insurance.  Not later than thirty (30) days before the
date on which GSK or any Affiliate or Sublicensee of GSK, or SYNTA or any
Affiliate or Sublicensee of SYNTA shall, on a commercial basis, make, use, or
sell any Products, and at all times thereafter until the expiration of all
applicable statutes of limitation pertaining to any such Manufacture,
marketing, possession, use, sale of other disposition of any Products, GSK
will, at its expense, and SYNTA will, at its expense, with respect to
Co-Commercialized Products, obtain and maintain in full force and effect,
comprehensive general liability insurance, including product liability
insurance and clinical trial insurance with a minimum coverage of $[***] per
occurrence and $[***] annual aggregate. 
Such insurance shall name the other Party as an additional insured and
shall provide for at least [***] days notice to the other Party of any
cancellation or termination. 
Notwithstanding the foregoing, GSK may elect to self-insure with respect
to any insurance coverage it is required to obtain hereunder as part of a
comprehensive self-insurance program adopted by GSK.  13.5         Warranty
Disclaimer.  EXCEPT AS
OTHERWISE EXPRESSLY PROVIDED IN THIS AGREEMENT, NEITHER PARTY MAKES ANY
WARRANTY WITH RESPECT TO ANY TECHNOLOGY, GOODS, SERVICES, RIGHTS OR OTHER
SUBJECT MATTER     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   79


OF THIS AGREEMENT AND EACH
PARTY HEREBY DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT
LIMITATION, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT.  13.6         No
Warranty of Success. 
Nothing contained in this Agreement shall be construed as a warranty,
either express or implied, on the part of either Party that (a) the
Development Program will yield a Product or otherwise be successful or meet its
goals, time lines or budgets, or (b) the outcome of the Development
Program will be commercially exploitable in any respect.  13.7         Limited
Liability. 
NOTWITHSTANDING ANYTHING TO THE CONTRARY IN THIS AGREEMENT, NEITHER
PARTY SHALL BE LIABLE TO THE OTHER PARTY OR ANY OF ITS AFFILIATES FOR (A) ANY
SPECIAL, PUNITIVE, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING,
WITHOUT LIMITATION, LOST PROFITS OR LOST REVENUES, OR (B) COST OF
PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, WHETHER UNDER ANY
CONTRACT, WARRANTY, NEGLIGENCE, STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE
THEORY; PROVIDED,THAT THIS LIMITATION WILL NOT LIMIT THE
INDEMNIFICATION OBLIGATION OF A PARTY UNDER THE PROVISIONS OF ARTICLE 13 FOR
SUCH DAMAGES CLAIMED BY A THIRD PARTY.  14.          MISCELLANEOUS  14.1Arbitration.In the event of any dispute,
difference or question arising between the Parties in connection with this
Agreement, the construction thereof, or the rights, duties or liabilities of
either Party hereunder (each, an Arbitration Matter), the arbitration
proceeding shall be conducted in accordance with the Commercial Arbitration Rules and
Supplementary Procedures for Large Complex Disputes of the American Arbitration
Association (the AAA) and otherwise as follows:  (a)The arbitration shall be conducted by either a single
arbitrator or a panel of three (3) persons who are experienced in the
biotechnology or pharmaceutical business; provided, that the Parties shall
agree in advance as to the number of arbitrators and hereby agree that a panel
of three (3) arbitrators shall be used if the Arbitration Matter is
sufficiently complex such that the best resolution is more likely to be
achieved with a group of experts, but that in general, the Parties shall work
to reduce the time and cost associated with each Arbitration Matter by using a
single arbitrator where appropriate.  The
Parties shall cooperate to attempt to select the arbitrators by agreement
within [***] days of the initiation of arbitration.  If agreement cannot be reached with such
[***] days, then that AAA will submit a list of [***] qualified arbitrators
from which each Party shall strike unacceptable entries; provided that each
Party shall not strike more than [***] percent ([***]%) of the names without
cause, and rank the remaining names.  The
AAA shall appoint the arbitrators with the highest combined ranking(s).  If these procedures fail to result in
selection of the required number of arbitrators, the AAA shall appoint the
arbitrator(s), allowing each side challenges for cause.The place of arbitration
shall be [***] and all proceedings and communications shall be in English.     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   80


(b)           Either Party may
apply to the arbitrators for interim injunctive relief until the arbitration
decision is rendered or the Arbitration Matter is otherwise resolved.  Either Party also may, without waiving any
right or remedy under this Agreement, seek from any court having jurisdiction
any injunctive or provisional relief necessary to protect the rights or
property of that Party pending resolution of the Arbitration Matter pursuant to
this Section 14.1.  The arbitrators
shall have no authority to award punitive or any other type of damages not
measured by a Partys compensatory damages. 
Each Party shall bear its own costs and expenses and attorneys fees,
and the Party that does not prevail in the arbitration proceeding shall pay the
arbitrators fees and any administrative fees of arbitration.  (c)           Except to the extent
necessary to confirm an award or decision or as may be required by Applicable
Laws, neither a Party nor an arbitrator may disclose the existence, content, or
results of an arbitration without the prior written consent of both
Parties.  In no event shall arbitration
be initiated after the date when commencement of a legal or equitable
proceeding based on the Arbitration Matter would be barred by the applicable
[***] statute of limitations.  (d)           The Parties agree
that, in the event of an Arbitration Matter involving the alleged breach of
this Agreement (including, without limitation, whether a Party has satisfied
its diligence obligations hereunder), neither Party may terminate this
Agreement until resolution of the Arbitration Matter pursuant to this Section 14.1,
and any time period for cure will only commence after such resolution.  (e)           The Parties hereby
agree that any disputed performance or suspended performance pending the
resolution of an Arbitration Matter that the arbitrators determine to be
required to be performed by a Party must be completed within a reasonable time
period following the final decision of the arbitrators.  (f)            The Parties hereby
agree that any monetary payment to be made by a Party pursuant to a decision of
the arbitrators shall be made in United States dollars, free of any tax or
other deduction.  (g)           The Parties further
agree that the decision of the arbitrators shall be the sole, exclusive and
binding remedy between them regarding determination of Arbitration Matters
presented.  14.2         Notices.  All notices and communications shall be in
writing and delivered personally or by internationally-recognized overnight
express courier providing evidence of delivery or mailed via certified mail,
return receipt requested, addressed as follows, or to such other address as may
be designated from time to time:  If to GSK:
  
  GlaxoSmithKlineGreenford RoadGreenfordMiddlesexUB6 0HEUnited Kingdom
   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   81


Attention: Vice President,Worldwide Business Development - TransactionsTel.: [***]Fax: [***]With a copy to:GlaxoSmithKline2301 Renaissance BoulevardMailcode RN0220King of Prussia, PA 19406-2772Attention: Vice President and Associate General
  Counsel,Business Development TransactionsTel.: [***]Fax: [***]If to SYNTA:
  Synta Pharmaceuticals Corp .45 Hartwell Ave.Lexington, MA 02421Attention: Martin D. Williams, ChiefBusiness OfficerTel: [***]Fax: [***]With copies to:Synta Pharmaceuticals Corp.45 Hartwell Ave.Lexington, MA 02421Attention: General CounselTel: [***]Fax: [***]Mintz, Levin, Cohn, Ferris, Glovskyand Popeo, P.C.One Financial CenterBoston, Massachusetts 02111Attention: Jeffrey M. Wiesen, Esq.Tel: [***]Fax: [***]   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   82


In addition, all notices to the JSC, JDC, JPC or JCC shall be sent to
each Partys designated members of such committees at such Partys address
stated above or to such other address as such Party may designate by written
notice given in accordance with this Section 14.2.  Except as otherwise expressly provided in this
Agreement or mutually agreed in writing, any notice, communication or document
(excluding payment) required to be given or made shall be deemed given or made
and effective upon actual receipt or, if earlier, (a) [***] Business Days
after deposit with an internationally-recognized overnight express courier with
charges prepaid, or (b) [***] Business Days after mailed by certified,
registered or regular mail, postage prepaid, in each case addressed to a Party
at its address stated above or to such other address as such Party may
designate by written notice given in accordance with this Section 14.2.  14.3         Governing Law.  This Agreement shall be governed by and
construed in accordance with the laws of theState
of New York(U.S.A.), without
regard to the application of principles of conflicts of law.  Notwithstanding the foregoing, with respect
to any dispute relating to the determination of
scope, validity or enforceability of any Patent Rights, the Parties consent to
the exclusive jurisdiction of the courts of the country the Applicable Laws of
which cause that Patent Right to come into being and where such courts have
jurisdiction, the dispute shall be determined according to the laws of that
country.  14.4         Binding
Effect.  This Agreement
shall be binding upon and inure to the benefit of the Parties and their
respective legal representatives, successors and permitted assigns.  14.5         Headings.  Section and subsection headings are
inserted for convenience of reference only and do not form a part of this
Agreement.  14.6         Counterparts.  This Agreement may be executed simultaneously
in two or more counterparts, each of which shall be deemed an original and both
of which, together, shall constitute a single agreement.  14.7         Amendment;
Waiver.  This Agreement
may be amended, modified, superseded or canceled, and any of the terms of this
Agreement may be waived, only by a written instrument executed by each Party
or, in the case of waiver, by the Party or Parties waiving compliance.  The delay or failure of either Party at any
time or times to require performance of any provisions shall in no manner
affect the rights at a later time to enforce the same.  No waiver by either Party of any condition or
of the breach of any term contained in this Agreement, whether by conduct, or
otherwise, in any one or more instances, shall be deemed to be, or considered
as, a further or continuing waiver of any such condition or of the breach of
such term or any other term of this Agreement.  14.8         No
Third Party Beneficiaries. 
Except as set forth in Sections 13.1 and 13.2, no Third Party
(including, without limitation, employees of either Party) shall have or
acquire any rights by reason of this Agreement.  14.9         Purposes
and Scope.  The Parties
hereto understand and agree that this Collaboration is limited to the
activities, rights and obligations as set forth in this Agreement and the Stock
Purchase Agreement, and as agreed by the Parties pursuant to a written document     Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   83


executed by the Parties
specifically referencing this Agreement. 
Nothing in this Agreement shall be construed (a) to create or imply
a general partnership between the Parties, (b) to make either Party the
agent of the other for any purpose, (c) to alter, amend, supersede or
vitiate any other arrangements between the Parties with respect to any subject
matters not covered hereunder, (d) to give either Party the right to bind
the other, (e) to create any duties or obligations between the Parties
except as expressly set forth herein, or (f) to grant any direct or
implied licenses or any other right other than as expressly set forth herein.  14.10       Assignment
and Successors.  Neither
this Agreement nor any obligation of a Party hereunder may be assigned by
either Party without the consent of the other which shall not be unreasonably
withheld, except that each Party may assign this Agreement and the rights,
obligations and interests of such Party, (a) in whole or in part, to any
of its Affiliates, or (b) in whole, but not in part, to any purchaser of
all of its assets or all of its assets to which this Agreement relates or
shares representing a majority of its common stock voting rights or to any
successor corporation resulting from any merger, consolidation, share exchange
or other similar transaction. 
Notwithstanding the foregoing, if SYNTA enters into an agreement that
results or, if the transaction contemplated thereby is completed, would result,
in a Change of Control, SYNTA shall provide GSK with prompt written notice
describing such Change of Control in reasonable detail (the Change of Control
Notice).  The Change of Control Notice
shall be provided by SYNTA prior to execution of such agreement, if permitted
under Applicable Laws and not prohibited by the terms of any agreement between
SYNTA and any Third Party; provided, that SYNTA will use reasonable efforts to
exclude any such prohibition in such agreement with a Third Party, and
otherwise as soon as practicable thereafter and, in any event, not later than
promptly following the consummation of the transaction contemplated by such
agreement.  Within [***] days after such
Change of Control Notice is provided by SYNTA, GSK shall have the right to
provide written notice to SYNTA, in its sole discretion, terminating SYNTAs
rights to participate in the Co-Commercialization activities as described
below.  If GSK should fail to give such
notice to SYNTA within such [***] day period, GSK shall have no further rights
under this Section 14.10 as a result of the Change of Control described in
the Change of Control Notice and the terms of this Agreement shall continue in
full force and effect following such Change of Control.  If GSK gives such notice to SYNTA within such
[***] day period and a Change of Control is consummated, the following shall
apply: (i) SYNTA shall have no further right to conduct any Development of
any Product in any Indication anywhere in the Territory and GSK shall be solely
responsible for any such Development in its sole discretion,(ii) SYNTA shall have no further
right to conduct SYNTA Co-Commercialization Activities for any
Co-Commercialized Product in any Indication anywhere in the Territory, and any
on-going SYNTA Co-Commercialization Activities shall be transitioned to GSK in
an orderly manner that does not result in a negative impact to sales of the Product,
or availability of Product to patients, (iii) unless otherwise designated
by SYNTA in writing within [***] days of its receipt of such notice from GSK,
all Co-Commercialized Products shall remain as Co-Commercialized Products
solely for purposes of Section 6.3 and the Parties shall continue to share
Operating Income as calculated in accordance with Schedule 4, with
respect thereto pursuant to Section 6.3, (iv) GSK shall have all
decision-making authority for all further Development and Commercialization and
all other matters, including matters that would otherwise be SYNTA Decisions or
Unanimous Decisions in all Indications including metastatic melanoma, (iv) the
JDC and JCC shall be terminated as soon as practicable, (v) if the Product
is    Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.    84


in Development at the time
of the Change of Control, the Parties would continue to share Development Costs
as set forth in Section 3.6.1, and (vi) GSK shall keep SYNTA
periodically informed of material updates with respect to Development and
Commercialization of Products.  14.11       Force
Majeure.  Neither GSK nor
SYNTA shall be liable for failure of or delay in performing obligations set
forth in this Agreement, and neither shall be deemed in breach of its
obligations, if such failure or delay is due to a Force Majeure.  In event of such Force Majeure, the Party
affected shall use reasonable efforts to cure or overcome the same and resume
performance of its obligations hereunder.  14.12Interpretation.The Parties hereto acknowledge and
agree that: (a) each Party and its counsel reviewed and negotiated the
terms and provisions of this Agreement and have contributed to its revision; (b) the
rule of construction to the effect that any ambiguities are resolved
against the drafting Party shall not be employed in the interpretation of this
Agreement; and (c) the terms and provisions of this Agreement shall be
construed fairly as to each Party and not in a favor of or against either
Party, regardless of which Party was generally responsible for the preparation
of this Agreement.  In addition, (a) unless
a context otherwise requires, wherever used, the singular shall include the
plural, the plural the singular, the use of any gender shall be applicable to
all genders, the word or is used in the inclusive sense (and/or) and the word
including is used without limitation and means including without limitation and (b) whenever
a defined term itself contains another defined term, the definition of this
compounded defined term shall govern in the case of any ambiguity or conflict
between the defined terms.  14.13       Integration;
Severability.  Except as
agreed by the Parties pursuant to a written document executed by the Parties
specifically referencing this Agreement, this Agreement, and the Stock Purchase
Agreement set forth the entire agreement with respect to the subject matter
hereof and thereof and supersede all other agreements and understandings
between the Parties with respect to such subject matter.  If any provision of this Agreement is or
becomes invalid or is ruled invalid by any court of competent jurisdiction or
is deemed unenforceable, it is the intention of the Parties that the remainder
of this Agreement shall not be affected.  14.14       Further
Assurances.  Each of SYNTA
and GSK agrees to duly execute and deliver, or cause to be duly executed and
delivered, such further instruments and do and cause to be done such further
acts and things, including, without limitation, the filing of such additional
assignments, agreements, documents and instruments, as the other Party may at
any time and from time to time reasonably request in connection with this
Agreement or to carry out more effectively the provisions and purposes of, or
to better assure and confirm unto such other Party its rights and remedies
under, this Agreement.  14.15       HSR
Filing.  14.15.1Responsibilities of the Parties.If required by Applicable Law, each of SYNTA
and GSK shall, within ten (10) days after the Execution Date, file with
the United States Federal Trade Commission and the Antitrust Division of the
United States Department of Justice, any notification and report form required
of it in the reasonable opinion of both Parties under the HSR Act with respect
to the transactions contemplated hereby (an HSR Filing).The Parties    Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.    85


will cooperate with one
another to the extent necessary in the preparation of any such HSR Filing.  Each Party will be responsible for its own
costs and expenses, and GSK shall be responsible for all filing fees associated
with any HSR Filing. Notwithstanding the foregoing, neither Party
shall be required to divest products or assets or materially change its
business if doing so is a condition of the transactions contemplated by this
Agreement.  14.15.2       Effective Date. If the Parties determine that an HSR Filing is
required, thenthe
Effective Date shall not occur until such time as the waiting period under the
HSR Act shall have expired or earlier been terminated; provided, that, (a) no
injunction (whether temporary, preliminary or permanent) prohibiting
consummation of the transactions contemplated by this Agreement or any material
portion hereof shall be in effect; and (b) no requirements or conditions
shall have been imposed in connection therewith that are not otherwise
reasonably satisfactory to the Parties (collectively, the HSR Conditions).This Section 14.15
shall bind the Parties upon the Execution Date but the remaining provisions of
this Agreement shall not become effective until the Effective Date.  If the
Effective Date does not occur on or prior to [***] months from the Execution
Date, either Party may terminate this Agreement on not less than [***] days
written notice.  [Remainder of page intentionally left blank.]      Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   86


IN
WITNESS WHEREOF, the Parties have caused this Agreement to be executed by their
duly authorized representatives.  SYNTA
  PHARMACEUTICALS CORP.By:
  /s/ SAFI R. BAHCALLName: Safi R. BahcallTitle:
  President and Chief Executive OfficerSMITHKLINE BEECHAM CORPORATION(d/b/a GlaxoSmithKline)By:
  /s/
  [***]Name:
  [***]Title:
  Vice President & Secretary        Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    87


EXHIBIT A  FORM OF STOCK PURCHASE AGREEMENT   STOCK PURCHASE AGREEMENT  by and between  SYNTA PHARMACEUTICALS CORP.  and  SMITHKLINE BEECHAM CORPORATION  (d/b/a GLAXOSMITHKLINE)   Dated as of
[          ]     Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Exhibit A-1


STOCK PURCHASE AGREEMENT  THIS STOCK PURCHASE AGREEMENT
dated as of [          ] (the
Agreement) is made by and between Synta Pharmaceuticals Corp., a Delaware
corporation (the Company), and SmithKline Beecham Corporation (doing business
as GlaxoSmithKline), a Pennsylvania corporation (the Purchaser).  WHEREAS, the Company desires to
issue and sell to the Purchaser, and the Purchaser desires to purchase, shares
of the Companys common stock, par value $.0001 per share (Common Stock), as
provided in Section [4.2.1/4.2.2] of that certain Collaborative
Development and Commercialization Agreement between the Company and the
Purchaser dated October 5, 2007;  NOW, THEREFORE, in consideration
of the premises and mutual agreements set forth herein and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
mutually acknowledged, and intending to be legally bound hereby, the parties
hereto agree as follows:  SECTION 1Definitions  1.1           For purposes of this
Agreement, the following terms shall have the meanings set forth below:  (a)           Actshall mean the Securities Act
of 1933, as amended, or any similar federal statute and the rules, regulations
and policies of the Commission thereunder, all as the same shall be in effect
at the time.  (b)Affiliate
shall mean an individual, trust, business trust, joint venture, partnership,
corporation, limited liability company, association or any other entity which
(directly or indirectly) is controlled by, controls or is under common control
with the Company or the Purchaser, as the case may be.  For the purposes of this definition, the term
control (including, with correlative meanings, the term controlled by and under
common control with) as used with respect to the Company or the Purchaser, as
the case may be, means the possession of the power to direct or cause the
direction of the management and policies of an entity, through the ownership of
the outstanding voting securities or by contract or otherwise.  (c)By-laws
shallmeanthe Restated
By-Laws of the Company, as amended from time to time.  (d)           Certificate of
Incorporation shall mean the Companys Restated Certificate ofIncorporationon file with
the Secretary of State of the State of Delaware, as amended from time to time.  (e)           Closing and ClosingDateshall have the meanings
specified in Section 2.2 hereof.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.  Exhibit A-2


(f)            Commission shallmeanthe Securities
and Exchange Commission or any other federal agency at the time administering
the Act.  (g)           Common Stock shallhavethe meaning
specified in the recitals.  (h)           Exchange Act shallhavethe meaning
specified in Section 3.8(a) hereof.  (i)            Purchase Price shall have the
meaning specified in Section 2.1 hereof.  (j)            SEC Documents shall mean each
report, registration statement and definitive proxy statement filed by the
Company with the Commission since [INSERT DATE THAT IS ONE YEAR BEFORE DATE OF
THIS AGREEMENT], and all amendments or supplements thereto.  (k)           Sharesshall have the meaning
specified in Section 2.1 hereof.  1.2           Certain other words
and phrases are defined or described elsewhere in this Agreement (and the
Exhibits and Schedules hereto, if any).  1.3           Wherever used in
this Agreement:  (l)            the words include or including shall be construed as
also incorporating but not limited to and without limitation;  (m)          the word day means a calendar day unless
specified otherwise; and  (n)           the word law (or laws) means any statute, ordinance, regulation or
code.  1.4           Unless specified to
the contrary, references to Articles, Sections Schedules and/or Exhibits mean
the particular Article, Section, Schedule or Exhibit in or to this
Agreement.  1.5           References to this
Agreement shall include this Agreement as varied or modified from time to time
by the parties.  1.6           Unless the context
requires otherwise, words in the singular number include the plural and vice
versa.  1.7           All Schedules and
Exhibits hereto are hereby incorporated herein and made a part hereof.  SECTION 2 Authorization, Purchase and Sale of the Shares  2.1           Purchase and Sale of the Shares.  At the Closing (as defined in Section 2.2
hereof), and subject to the terms and conditions hereof and in reliance upon
the representations,    Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-3


warranties
and agreements contained herein, the Company shall issue and sell to the
Purchaser and the Purchaser shall purchase from the Company
[          ] shares of Common
Stock (the Shares) at a purchase price of
$[          ] per share for a
total purchase price of
$[          ] (the Purchase Price).  2.2           Closing.  The purchase and sale of the Shares being
purchased by the Purchaser shall take place at the offices of Mintz, Levin,
Cohn, Ferris, Glovsky and Popeo, P.C., One Financial Center, Boston, MA  02111, at 10:00 a.m., local time, on
[          ], or at such other
location, date and time as may be agreed upon among the Purchaser and the
Company (such closing being called the Closing
and such date and time being called the Closing Date).  At the Closing, the Company shall issue and
deliver to the Purchaser a certificate in definitive form, registered in the
name of the Purchaser, representing the Shares being purchased by the Purchaser
at the Closing.  As payment in full for
the Shares being purchased by it under this Agreement, and against delivery of
the certificate therefor as aforesaid, on the Closing Date, the Purchaser shall
transfer such amount to the account of the Company by wire transfer of
immediately available funds to the bank account designated by the Company in
writing to the Purchaser at least two business days before the Closing Date.  SECTION 3 Representations and Warranties and Certain Covenants of the Company  Except
as set forth in the SEC Documents or in any disclosure schedules delivered
herewith (which shall be numbered to correspond with the sections of this Section 3),
the Company hereby represents and warrants to and covenants to the Purchaser as
follows:  3.1           Organization, Qualifications and
Corporate Power.  The Company is a
corporation duly incorporated, validly existing and in good standing under the
laws of the State of Delaware and the Company is duly licensed or qualified to
transact business as a foreign corporation and is in good standing in each
jurisdiction in which the nature of the business transacted by it or the
character of the properties owned or leased by it requires such licensing or
qualification, except where failure to qualify would not have a material
adverse effect on the business or financial condition of the Company.  The Company has the corporate power and
authority to own and hold its properties and to carry on its business as now
conducted, to execute, deliver and perform this Agreement and any other
agreements, documents or instruments contemplated hereby to which it is a
party, to issue, sell and deliver the Shares.  3.2           Authorization of Agreements, Etc.  (a)           The execution and
delivery by the Company of this Agreement, the performance by the Company of
its obligations hereunder, and the issuance, sale and delivery of the Shares
have been duly authorized by all requisite corporate action and will not
violate any provision of law, any order of any court or other agency of
government specifically naming the Company, the Certificate of Incorporation,
or the By-laws or any material provision of any indenture, agreement or other
instrument to which the Company is a party or by which it or its assets are
bound, or conflict with, result in a breach of or constitute (with due notice
or lapse of   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-4


time
or both) a default under any such indenture, agreement or other instrument,
which violation, conflict or default could have a material adverse effect on
the Company, or result in the creation or imposition of any material lien,
charge, restriction, claim or encumbrance upon any of the properties or assets
of the Company.  (b)           The Shares have been
duly authorized and the Shares, when issued in accordance with this Agreement,
will be validly issued, fully paid and nonassessable and free of all liens,
charges, restrictions, claims and encumbrances imposed by or through the Company.  None of the issuance, sale or delivery of the
Shares is subject to any preemptive right of stockholders of the Company or to
any right of first refusal or other right in favor of any person which has not
been waived.  3.3           Validity.  This Agreement has been duly executed and
delivered by the Company.  This Agreement
constitutes the legal, valid and binding obligations of the Company,
enforceable in accordance with its terms subject to bankruptcy, insolvency,
reorganization, moratorium and other similar laws affecting the rights of
creditors and to general principles of equity.  3.4           Consents.  All consents, approvals, orders, or
authorizations of, or registrations, qualifications, designations,
declarations, or filings with any federal or state governmental authority, any
party to a contract to which the Company or its assets are bound or any other
third party on the part of the Company required in connection with the
consummation of the transactions contemplated by this Agreement shall have been
obtained prior to, and be effective as of, the Closing (other than such filings
under the blue sky law of any state governmental authority and any federal
securities law filings that may be made after the Closing, which such filings
shall be timely made).  3.5           Subsidiaries.  The Company has no subsidiaries other than as
disclosed in the SEC Documents.  3.6           Capitalization.  The authorized and outstanding shares of
capital stock and options, warrants and other rights to purchase capital stock
of the Company is as set forth in the latest periodic report that comprises a
part of the SEC Documents.  All issued
and outstanding shares of the Companys capital stock have been duly authorized
and validly issued, are fully paid and nonassessable, and were issued in
compliance with all applicable state and federal laws concerning the issuance
of securities.  3.7           Litigation.  There is no (i) action, suit, claim,
proceeding or investigation pending or, to the best of the Companys knowledge,
threatened against the Company, at law or in equity, or before or by any
federal, state, municipal or other governmental department, commission, board,
bureau, agency or instrumentality, domestic or foreign, (ii) arbitration
proceeding relating to the Company pending under collective bargaining agreements
or otherwise or (iii) governmental inquiry pending or, to the best of the
Companys knowledge, threatened against the Company (including without
limitation any inquiry as to the qualification of the Company to hold or
receive any license or permit), and to the best of the Companys knowledge
there is no basis for any of the foregoing.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-5


3.8           SEC Documents and Financial
Statements.  (a)           As of their
respective dates, the SEC Documents (i) were prepared in accordance with
the requirements of the Act or the Securities Exchange Act of 1934, as amended
(the Exchange Act), as
the case may be, and the rules and regulations of the Commission
thereunder applicable to such SEC Documents, and (ii) did not at the time
they were filed (or if amended or superseded by a filing prior to the date of
this Agreement, then on the date of such filing) contain any untrue statement
of a material fact or omit to state a material fact required to be stated
therein or necessary in order to make the statements therein, in the light of
the circumstances under which they were made, not misleading.  [The certifications and statements required
by (A) Rule 13a-14 under the Exchange Act and (B) 18 U.S.C.
§1350 (Section 906 of the Sarbanes-Oxley Act) relating to the SEC
Documents are accurate and complete and comply as to form and content with all
applicable legal requirements.]  (b)           The financial
statements (including any related notes) of the Company and its consolidated
subsidiaries contained in the SEC Documents: (i) complied as to form in
all material respects with the published rules and regulations of the
Commission applicable thereto; (ii) were prepared in accordance with
United States generally accepted accounting principles applied on a consistent
basis throughout the periods covered (except as may be indicated in the notes
to such financial statements or, in the case of unaudited statements, as
permitted by Form 10-Q of the Commission and except that unaudited
financial statements may not contain footnotes and are subject to normal and
recurring year-end audit adjustments which will not, individually or in the
aggregate, be material in amount), and (iii) fairly presented the
consolidated financial position of the Company and its consolidated
subsidiaries as of the respective dates thereof and the consolidated results of
operations and cash flows of the Company and its consolidated subsidiaries for
the periods covered thereby.  3.9           Taxes.  The Company has accurately prepared in all
material respects and timely filed all federal, state, county and local tax
returns required to be filed by it, and the Company has paid all taxes required
to be paid by it pursuant to such returns as well as all other taxes,
assessments and governmental charges which have become due or payable, including,
without limitation all taxes which the Company is obligated to withhold from
amounts owing to employees, creditors and third parties. All such taxes with
respect to which the Company has become obligated pursuant to elections made by
the Company in accordance with generally accepted practice have been paid and
adequate reserves have been established for all taxes accrued but not payable.  3.10         Intellectual Property.  The Company owns or possesses adequate
licenses or other rights to use all patents, patent applications, trademarks,
trademark applications, service marks, service mark applications, trade names,
copyrights, manufacturing processes, formulae, trade secrets, customer lists
and know how (collectively, Intellectual Property)
necessary to the conduct of its business as conducted consistent with the
description of the Companys business as set forth in the SEC Documents.  Without diminishing the representation set
forth in the preceding sentence, the Company further represents that it has
taken commercially reasonable steps to ensure that all right, title and
interest in any Intellectual Property which has been   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.  Exhibit A-6


developed
by key employees or founders of the Company in their capacity as either
employees or consultants to the Company which is necessary for the conduct of
the Companys business as conducted has been unconditionally assigned to the
Company.  3.11         Brokers.  The Company has no contract, arrangement or
understanding with any broker, finder or similar agent with respect to the
transactions contemplated by this Agreement.  3.12         Insurance.  The Company will use its commercially
reasonable efforts to maintain insurance with financially sound and reputable
insurance companies or associations, in such amounts and covering such risks as
are adequate and customary for the type and scope of its properties and
business as currently conducted and as planned to be conducted in the
foreseeable future.  3.13         Offering Valid.  Assuming the accuracy of the representations
and warranties of Purchaser contained in Section 4 hereof, the offer, sale
and issuance of the Shares will be exempt from the registration requirements of
the Act, and will have been registered or qualified (or are exempt from
registration and qualification) under the registration, permit or qualification
requirements of all applicable state securities laws.  SECTION 4 Representations and Warranties of Purchaser  The
Purchaser represents and warrants to the Company as follows:  4.1           Experience.  The Purchaser: (a) is an accredited
investor within the definition of Regulation D promulgated under the Act; (b) is
experienced in evaluating and in investing in developing biotechnology
companies such as the Company and can afford a loss of its entire investment;
and/or (c) has a pre-existing personal or business relationship with the
Company and/or certain of its officers, directors or controlling persons of a
nature and duration that enable it to be aware of the character, business
acumen and financial circumstance of such persons.  4.2           Investment.  The Purchaser is acquiring the Shares for
investment for its own account and not with the view to, or for resale in
connection with, any distribution thereof. 
It understands that the Shares have not been registered under the Act by
reason of specified exemptions form the registration provisions of the Act.  4.3           Rule 144.  The Purchaser acknowledges that the Shares
must be held indefinitely unless they are subsequently registered under the Act
or an exemption from such registration is available.  It has been advised or is aware of the
provisions of Rule 144 promulgated under the Act, which permit limited
release of shares purchased in a private placement subject to the satisfaction
of certain conditions, and is aware that such Rule may not become
available for resale of the Shares.  4.4           Access to Data.  The Purchaser has had an opportunity to
discuss the Companys business, management and financial affairs with the
Companys management and has had the opportunity to review the Companys
facilities.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.  Exhibit A-7


4.5           Brokers.  The Purchaser has no contract, arrangement or
understanding with any broker, finder or similar agent with respect to the
transactions contemplated by this Agreement.  4.6           Foreign Purchaser.  The Purchaser hereby represents that it is
satisfied as to the full observance of the laws of its jurisdiction in
connection with any purchase of the Shares or any use of this Agreement,
including (i) the legal requirements of its jurisdiction for the purchase
of the Shares, (ii) any foreign exchange restrictions applicable to such
purchase, (iii) any governmental or other consents that may need to be
obtained, and (iv) the income tax and other tax consequences, if any,
which may be relevant to the purchase, holding, redemption, sale, or transfer
of the Shares.  The Purchasers purchase
of, and its continued beneficial ownership of, the Shares will not violate any
applicable securities or other laws of its jurisdiction.  4.7           Authorization.  The Purchaser has full power and authority to
enter into and to perform this Agreement in accordance with its terms. All
action (corporate or otherwise) on the part of the Purchaser necessary for the
authorization, execution, delivery and performance by the Purchaser of this
Agreement and the consummation of the transactions contemplated herein has been
taken. This Agreement is valid and binding obligation of the Purchaser,
enforceable in accordance with its terms, subject to bankruptcy, insolvency,
reorganization, moratorium and other similar laws affecting the rights of
creditors and to general principles of equity.  SECTION 5 Other Agreements of the Parties  5.1           Transfer Restrictions.  (a)           The Purchaser
covenants that the Shares will only be disposed of pursuant to an effective
registration statement under, and in compliance with the requirements of, the
Act or pursuant to an available exemption from the registration requirements of
the Act, and in compliance with any applicable state securities laws.  In connection with any transfer of the Shares
other than pursuant to an effective registration statement or to the Company,
the Company may require the Purchaser to provide to the Company an opinion of
counsel selected by the Purchaser, the form and substance of which opinion
shall be reasonably satisfactory to the Company, to the effect that such
transfer does not require registration under the Act.  Notwithstanding the foregoing, the Company
hereby consents to and agrees to register on the books of the Company and with
its transfer agent, without any such legal opinion, except to the extent that
the transfer agent requests such legal opinion, any transfer of the Shares by
the Purchaser to an Affiliate of the Purchaser, provided, that the transferee
certifies to the Company that it is an accredited investor within the
definition of Regulation D promulgated under the Act and, provided, further,
that such Affiliate does not request any removal of any existing legends on any
certificate evidencing the Shares.  (b)           The Purchaser agrees
to the imprinting of the following legend on any certificate evidencing any of
the Shares:  THESE
SECURITIES HAVE NOT BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION
OR THE SECURITIES   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-8


COMMISSION
OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM REGISTRATION UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE SECURITIES ACT), OR ANY APPLICABLE
STATE SECURITIES LAWS AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT
PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR
PURSUANT TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO,
THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN COMPLIANCE WITH
APPLICABLE STATE SECURITIES LAWS OR BLUE SKY LAWS.  Certificates
evidencing the Shares shall not be required to contain such legend or any other
legend (i) while a registration statement covering the resale of the
Shares is effective under the Act, (ii) following any sale of such Shares
pursuant to Rule 144, (iii) the Shares are eligible for sale under Rule 144(k),
or (iv) if legend is not required under applicable requirements of the Act
(including controlling judicial interpretations and pronouncements issued by
the Staff of the Commission).  5.2           Furnishing of Information.  Until the date that the Purchaser may sell
all of the Shares under Rule 144(k) of the Act (or any successor
provision), the Company covenants to use its commercially reasonable efforts to
timely file (or obtain extensions in respect thereof and file within the
applicable grace period) all reports required to be filed by the Company after
the date hereof pursuant to the Exchange Act. 
Until the date that the Purchaser may sell all of the Shares under Rule 144(k) of
the Act (or any successor provision), the Company further covenants that it
will take such further action as the Purchaser may reasonably request to make
available the information specified in paragraph (c) of Rule 144.  5.3           Integration.  The Company shall not, and shall use its
commercially reasonably efforts to ensure that no Affiliate of the Company
shall, sell, offer for sale or solicit offers to buy or otherwise negotiate in
respect of any security (as defined in Section 2 of the Act) that would be
integrated with the offer or sale of the Shares in a manner that would require
the registration under the Act of the sale of the Shares to the Purchaser or
that would be integrated with the offer or sale of the Shares for purposes of
the rules and regulations of The NASDAQ Global Market (of, if the Common
Stock is not listed on The NASDAQ Global Market, the principal exchange or
interdealer quotation system on which the Common Stock is listed).  SECTION 6 Purchasers Conditions to Closing  The
Purchasers obligation to purchase Shares at the Closing is subject to the
fulfillment to its satisfaction on or prior to the Closing Date of each of the
following conditions:  6.1           Representations and Warranties.  The representations and warranties contained
in Section 3 shall be true, complete and correct on and as of the Closing
Date with the same effect as though such representations and warranties had
been made on and as of such date.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-9


6.2           Performance.  The Company shall have performed and complied
with all covenants, agreements and conditions contained herein required to be
performed or complied with by it prior to or at the Closing Date.  6.3           Legal Investment.  At the time of the Closing, the purchase of
the Shares shall be legally permitted by all laws and regulations to which the
Purchaser and the Company are subject.  6.4           Proceedings and Documents.  All corporate and other proceedings in
connection with the transactions contemplated hereby and all documents and
instruments incident to such transactions shall be reasonably satisfactory in
form and substance to the Purchaser and its counsel. Prior to the Closing, the
Company shall have obtained all consents or waivers, if any, necessary to
execute and deliver this Agreement, issue the Shares and to carry out the
transactions contemplated hereby and thereby, and all such consents and waivers
shall be in full force and effect.  6.5           Qualifications.  All other authorizations, approvals or
permits if any, of any governmental authority or regulatory body of the United
States or any state that are required prior to and in connection with the
lawful issuance and sale of the Shares pursuant to this Agreement shall be
effective on and as of the Closing Date.  SECTION 7 Companys Conditions to Closing  The
Companys obligation to sell the Shares at the Closing is subject to the
fulfillment on or prior to the Closing Date of each of the following
conditions:  7.1           Representations and Warranties.  The representations and warranties made by
the Purchaser pursuant to Section 4 hereof shall be true and correct when
made and shall be true and correct on the Closing Date.  7.2           Performance.  The Purchaser shall have performed and
complied with all covenants, agreements and conditions contained herein
required to be performed or complied with by it prior to or at the Closing
Date.  7.3           Legal Investment.  At the time of the Closing, the purchase of
the Shares shall be legally permitted by all laws and regulations to which the
Purchaser and the Company are subject.  7.4           Payment of Purchase Price.  The Purchaser shall have delivered to the
Company a wire transfer of immediately available funds to the account of the
Company in the full amount of the Purchase Price.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-10


SECTION 8 Miscellaneous  8.1           Governing Law.  This Agreement shall be governed in all
respects by the laws of the State of Delaware without giving effect to
principles of conflicts of law thereunder.  8.2           Survival.  The representations, warranties, covenants
and agreements made herein shall survive the closing of the transactions
contemplated hereby.  All statements as
to factual matters contained in any certificate or other instrument delivered
by or on behalf of the Company pursuant hereto in connection with the
transactions contemplated hereby shall be deemed to be representations and
warranties by the Company hereunder solely as of the date of such certificate
or instrument.  8.3           Successors and Assigns.  Except as otherwise expressly provided
herein, the provisions hereof shall inure to the benefit of, and be binding
upon, the successors, assigns, heirs, executors and administrators of the
parties hereto.  Nothing in this
Agreement, express or implied, is intended to confer upon any party other than
the parties hereto or their respective successors and assigns any rights,
remedies, obligations, or liabilities under or by reason of this Agreement,
except as expressly provided in this Agreement. Subject to the terms of this Agreement,
no party hereby may assign its rights or obligations hereunder (whether by
operation of law or otherwise, including by merger, asset sale, sale of stock
or otherwise) without the prior written consent of the other parties hereto.  8.4           Entire Agreement; Amendment and
Waiver.  This Agreement (including
the Schedules and Exhibits hereto, if any) and the other documents delivered
pursuant hereto constitute the full and entire understanding and agreement
between the parties with regard to the subjects hereof and thereof.  Neither this Agreement nor any term hereof
may be amended, modified, waived or terminated, except by a written instrument
signed by the Company and the Purchaser.  8.5           Notices.  Unless otherwise provided, all notices,
requests, consents and other communications hereunder shall be in writing,
shall be addressed to the receiving partys address set forth below or to such
other address as a party may designate by notice hereunder, and shall be either
(i) delivered by hand, (ii) made by telecopy, facsimile transmission
or other electronic transmission, (iii) sent by overnight courier, or (iv) sent
by registered or certified mail, return receipt requested, postage prepaid.  If to the Company:
  
  Synta Pharmaceuticals Corp.45 Hartwell Ave.Lexington, MA 02421Attention: Martin D. Williams, ChiefBusiness OfficerTel: [***]Fax: [***]   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-11


With copies to:
  Synta Pharmaceuticals Corp.45 Hartwell Ave.Lexington, MA 02421Attention: General CounselTel: [***]Fax: [***]Mintz, Levin, Cohn, Ferris, Glovskyand Popeo, P.C.One Financial CenterBoston, Massachusetts 02111Attention: Jeffrey M.
  Wiesen, Esq.Tel: [***]Fax: [***]If to the Purchaser: :
  GlaxoSmithKlineGreenford RoadGreenfordMiddlesexUB6 0HEUnited KingdomAttention: Vice President,Worldwide Business Development - TransactionsTel.: [***]Fax: [***]With a copy to: :
  GlaxoSmithKline2301 Renaissance BoulevardMailcode RN0220King of Prussia, PA 19406-2772Attention:
  Vice President and Associate General Counsel, Business
  Development TransactionsTel.: [***]Fax: [***]  or,
in any such case, at such other address or addresses as shall have been furnished
in writing by such party to the others.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-12


All
notices, requests, consents and other communications hereunder shall be deemed
to have been given either (i) if by hand, at the time of the delivery
thereof to the receiving party at the address of such party set forth above, (ii) if
made by telecopy, facsimile transmission or other electronic transmission, at
the time that receipt thereof has been acknowledged by electronic confirmation
or otherwise, (iii) if sent by overnight courier, on the next business day
following the day such notice is delivered to the courier service, or (iv) if
sent by registered or certified mail, on the fifth business day following the
day such mailing is made.  8.6           Delays or Omissions.  No delay or omission to exercise any right,
power or remedy accruing to any holder of any shares upon any breach or default
of the Company under this Agreement shall impair any such right, power or
remedy of such holder nor shall it be construed to be a waiver of any such
breach or default, or an acquiescence therein, or in any similar breach or
default occurring thereafter; nor shall any waiver of any single breach or
default be deemed a waiver of any other breach or default theretofore or
thereafter occurring. Any waiver, permit, consent or approval of any kind or
character on the part of any holder or any breach or default under this
Agreement, or any waiver on the part of any holder of any provisions or
conditions of this Agreement must be made in writing and shall be effective
only to the extent specifically set forth in such writing. All remedies, either
under this Agreement or by law or otherwise afforded to any holder, shall be
cumulative and not alternative.  8.7           Severability.  If one or more provisions of this Agreement
are held to be unenforceable under applicable law, such provision shall be
excluded from this Agreement and the balance of the Agreement shall be
interpreted as if such provision were so excluded and shall be enforceable in
accordance with its terms.  8.8           Interpretation.  The parties hereby acknowledge and agree
that:  (i) each party and its
counsel reviewed and negotiated the terms and provisions of this Agreement and
have contributed to its revision; (ii) the rule of construction to
the effect that any ambiguities are resolved against the drafting party shall
not be employed in the interpretation of this Agreement; and (iii) the
terms and provisions of this Agreement shall be construed fairly as to all
parties hereto and not in a favor of or against any party, regardless of which
party was generally responsible for the preparation of this Agreement.  8.9           Further Assurances.  From and after the date of this Agreement,
the Company and the Purchaser shall execute and deliver such instruments,
documents or other writings as may be reasonably necessary or desirable to
confirm and carry out and to effectuate fully the intent and purposes of this
Agreement.  8.10         Headings.  The headings and subheadings used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.  8.11         Counterparts.  This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. One or more counterparts
of this Agreement may be delivered electronically with the intention that they
shall each have the same effect as an original counterpart hereof.   Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.    Exhibit A-13


[Remainder of Page Intentionally Left Blank]       Portions of this Exhibit were omitted and have
been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-14


IN
WITNESS WHEREOF, the parties have duly executed this Stock Purchase Agreement
as of the date first above written.  COMPANY:SYNTA
  PHARMACEUTICALS CORP.By:Name:Title:PURCHASER:SMITHKLINE
  BEECHAM CORPORATION(d/b/a
  GLAXOSMITHKLINE)By:Name:Title:    Portions of this Exhibit were omitted and
have been filed separately with the Secretary of the Commission pursuant to the
Companys application requesting confidential treatment under Rule 24b-2 of the
Securities Exchange Act of 1934.   Exhibit A-1


SCHEDULE 1  DESCRIPTION OF STA-4783    CHEMICAL
  NAME[***],STRUCTURAL
  FORMULA[***]MOLECULAR FORMULA
  [***]MOLECULAR WEIGHT
  [***]SYNTA
  CODE DESIGNATION
  STA-4783CAS
  REGISTRY NUMBER
  [***]    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 1-1


SCHEDULE 2  SYNTA PATENT RIGHTS  Country
  
  Application No.
  
  Patent No.
  
  Grant Date
  
  Status
  
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  Title
  
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  [***]   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    Sched. 2-1


[***]
  
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  [***]
  
  [***]   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 2-2


[***]
  
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  [***]   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    Sched. 2-3


SCHEDULE 3  RESERVED         Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    Sched. 3-1


SCHEDULE 4  CALCULATION AND MECHANICS FOR PAYMENT OF OPERATING
INCOME (LOSS) FOR THE CO-COMMERCIALIZATION TERRITORY  Advertising means the advertising and promotion of the
Co-Commercialized Products in the Co-Commercialization Territory through any
means, including, without limitation, (i) television and radio
advertisements; (ii) advertisements appearing in journals, newspapers,
magazines, the internet or other media; (iii) seminars and conventions; (iv) packaging
design; (v) professional education programs; (vi) visual aids and
other selling materials; (vii) hospital formulary committee presentations;
and (vii) presentations to state and other governmental formulary
committees; provided, however, that Advertising shall exclude Promotional
Efforts and General Public Relations. 
With regard to advertising and promotion that include products other
than Co-Commercialized Products, the JCC shall determine the percentage of such
advertising and promotion that will be deemed Advertising for the purposes of
this Agreement.  Commercialization Expense means the sum of (a) [***]; (b) any
reasonable internal and out-of-pocket costs, expenses and fees incurred in
prosecuting, maintaining, enforcing and defending the [***] covering a
Co-Commercialized Product in the Co-Commercialization Territory after receipt
of Commercialization Regulatory Approval; (c) [***]; (d) [***], and (e) any
other out-of-pocket cost or expense expressly stated to be a Commercialization
Expense in this Agreement or under the Product Co-Commercialization Plan.  Where an item of Commercialization Expense
has applicability to both the Co-Commercialization Territory and the
Royalty-Bearing Territory, it will be allocated by the JCC in good faith.  Cost of Goods means Manufacturing Costs attributable to the
Manufacture of a Co-Commercialized Product (including the cost of API) for sale
in the Co-Commercialization Territory and/or the cost of purchase of a
Co-Commercialized Product for sale in the Co-Commercialization Territory.  Promotional Efforts has the meaning provided in Section 1.  Distribution Fees means a distribution fee equal to [***]
percent ([***]%) of Net Sales in consideration of GSKs performance of the
physical distribution of the Product in the Co-Commercialization Territory.  General Public Relations means any public relations
activity (including a press release or image piece) which (i) promotes
generally the business of a company or deals in a general manner with the
activities of such company in a general pharmaceutical market; and (ii) mentions
in an incidental manner the fact that such company or its Affiliates markets or
sells one or more of the Co-Commercialized Products or provides other
incidental information concerning one or more of the Co-Commercialized
Products.  Announcements related to this
Agreement or that concern primarily the relationship of either Party to each
other are not General Public Relations and must be agreed upon by both Parties
in writing prior to release.   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 4-1


License Feesmeans all
upfront payments, milestone payments, license fees, royalties or other
payments, payable to any Third Party by either Party under any Third Party
license agreement related to the Manufacture or sale of a Co-Commercialized
Product to the extent such payments are attributable to sale of a
Co-Commercialized Product in the Co-Commercialization Territory.  With respect to milestone or other payments
(but not royalties, which are calculated on a country-by-country basis) made
pursuant to any Third Party license agreement which confers rights attributable
to products other than Co-Commercialized Products or sales of Products in the
ROW Territory, then only an equitable portion of any amounts payable under it
shall be allocated to Co-Commercialized Products as License Fees, as determined
by the Parties in good faith. Notwithstanding the foregoing, upfront payments,
milestone payments, license fees, royalties or other payments made pursuant to
the Third Party Agreements will not be included in this definition of License
Fees.  Net Sales has the meaning provided in Section 1.  Operating Income (Loss) means, with respect to a
Co-Commercialized Product, Net Sales in the Co-Commercialization Territory
minus the sum of (a) Cost of Goods of such Co-Commercialized Product and (b) Commercialization
Expense applicable to the Co-Commercialized Product, in each case, incurred in
a given Calendar Quarter for that Co-Commercialized Product.  Product Trademark has the meaning provided in Section 1.  Representative means anFTE employed by either Party who engages in Promotional Efforts,and is trained
by SYNTA or GSK.  Sales and Marketing Expense means all reasonable
out-of-pocket costs including, without limitation, costs of outsourcing any of the
following functions (as agreed upon by the JCC, but it is understood that SYNTA
shall not outsource Representatives and medical science liaisons) and all
internal costs on an allocated FTE basis at an agreed upon FTE rate for those
individuals dedicated or allocated to the Co-Commercialized Product incurred by
the Parties that are directly attributable to the following functions for the
sale, promotion and marketing of a Co-Commercialized Product in the
Co-Commercialization Territory:  (a) [***]
on such Co-Commercialized Product, (b) [***] of Co-Commercialized Products
(including, without limitation, [***] targeted specifically at Products, [***]
for the development of promotional materials and printing of promotional
materials), (c) [***] materials for the Co-Commercialized Products (d) [***]
accounts, (e) [***], (f) [***] in the Co-Commercialization Territory
for Co-Commercialized Products (including, without limitation, [***] costs for
any Co-Commercialized Product utilized in such [***] programs), (l) [***]
costs applicable to a Co-Commercialized Product.  For the avoidance of doubt, Sales and
Marketing Expense shall include that percentage of the agreed upon FTE rate
proportionate to the amount of Promotional Effort a particular Representative
contributes solely to the Co-Commercialized Product.  For example, if the equivalent of
[***] percent ([***]%) of each Representative of either Partys field force
conducts SYNTA Co-Commercialization Activities or GSK Co-Commercialization
Activities, as the case may be, for the Co-Commercialized Product, then only
[***] percent ([***]%) of the FTE rate applicable to each such Representative
shall be a Sales and Marketing Expense. Sales  Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 4-2


and
Marketing Expense shall not include any General Public Relations or any other
activities that promote the business of a Party as a whole without specifically
referencing any Co-Commercialized Product.  In
calculating the Operating Income (Loss) the following principles shall apply:  1.There shall be
no double counting of any costs or expenses or of any revenues, and to the
extent a cost or expense has been included in one category or sub-category, it
shall not be included in another; similarly, to the extent any revenue has been
taken into account in one category or sub-category it shall not be taken into
account in another.  2.When allocating
costs and expenses under this Agreement, each Party shall utilize the same
policies and principles as it utilizes consistently within its group and
business units when making internal cost allocations, as previously discussed
and agreed with the JCC.  3.To the extent
an item of income or revenue is received by a Party or a cost or expense is
incurred by a Party, and is necessary and specifically and directly
identifiable, attributable and allocable to the Commercialization of
Co-Commercialized Product and is not otherwise accounted for in the calculation
of Operating Income, such Party shall credit such income or revenue and shall
be permitted to charge such cost or expense to the Operating Income upon
approval of the JCC.  4.All costs and
expenses shall be determined, and all calculations shall be made, in accordance
with [***], as applicable.  5.Operating Income Payments.  (a)           In General. GSK shall pay to SYNTA the SYNTA
Operating Income (Loss) Sharing Percentage of the Operating Income (Loss)
attributable to each Co-Commercialized Product in the Co-Commercialization
Territory or SYNTA shall pay to GSK the SYNTA Operating Income (Loss) Sharing
Percentage of the Operating Loss attributable to each Co-Commercialized Product
in the Co-Commercialization Territory for as long as the Parties are conducting
SYNTA Co-Commercialization Activities and GSK Co-Commercialization Activities,
as the case may be, for such Co-Commercialized Product in the
Co-Commercialization Territory (such payments, the Operating Income Payments)
as described in this Section 5.  For
purposes of clarity, it is acknowledged that Commercialization Expenses will be
incurred prior to Commercialization Regulatory Approval of any
Co-Commercialized Product, and that such Commercialization Expenses will result
in an Operating Loss which will be borne by the Parties as set forth in this
Schedule 4.  (b)           Within [***] Business Days after the end of each [***]
SYNTA shall submit to GSK a report setting forth in reasonable detail its
estimated Operating Expenses with respect to each Co-Commercialized Product
attributable to such [***].   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 4-3


(c)           Within [***] Business Days following the end of each
[***], GSK shall submit a report setting forth in reasonable detail the
calculation of the amount of estimated Operating Income Payments payable to
SYNTA or Loss payable by SYNTA, determined by calculating the SYNTA Operating
Income (Loss) Sharing Percentage and GSK Operating Income (Loss) Percentage of
Operating Income (Loss) for that Co-Commercialized Product, attributable to
such [***].  Each Party shall pay any
Operating Income Payments payable to the other Party within [***] days of
receipt of the report described in this Subsection 5(c).  (d)           Within [***] Business Days following the end of each
[***], each of SYNTA and GSK shall submit to the JSC and the other Party the
actual Commercialization Expenses incurred by it with respect to, as well as
for GSK, the actual Net Sales of, Co-Commercialized Products in the
Co-Commercialization Territory, over that [***]. Within [***] days following
the receipt by GSK of SYNTAs written report, GSK shall prepare and submit to
SYNTA and the JSC a written report setting forth in reasonable detail (A) the
calculation of all such actual Commercialization Expenses incurred by each
Party and, with respect to GSK, the Net Sales received by GSK over such [***]
and (B) the calculation of the amount of Operating Income Payments payable
to SYNTA or Loss payable by SYNTA in accordance with the SYNTA Operating Income
(Loss) Sharing Percentage and GSK Operating Income (Loss) Percentage for that
Co-Commercialized Product, determined on the basis of the difference between
the Estimated Operating Income Payments paid in accordance with Section 5(c) and
the actual Commercialization Expenses incurred and Net Sales received by both
Parties over such [***] (the True-Up Operating Income Payment).  The amount of the True-Up Operating Income
Payments payable by either Party shall be paid within [***] days of receipt of
the report described in this Section 5(d).  (e)           All payments not made within the time period set forth
above in Section 5, including material underpayments discovered during an
audit, shall bear interest at a rate of [***] percent ([***]%) per month from
the due date until paid in full or, if less, the maximum interest rate
permitted by Applicable Laws. Such interest will not accrue on payments that
are the subject of a Disputed Matter or delay in payment is outside the paying
Partys reasonable control.  By
way of illustration, the following chart shows a calculation of monies due
under this mechanism (numbers represent millions of dollars):  Total
  Product
  P&L
  
  GSK P&L
  
  SYNTA P&LNet
  Sales
  
  [***]
  
  [***]
  
  [***]Cost
  of Goods
  
  [***]
  
  [***]
  
  [***]Commercialization
  Expenses:[***]
  
  [***]
  
  [***]
  
  [***][***]
  
  [***]
  
  [***]
  
  [***][***]
  
  [***]
  
  [***]
  
  [***][***]
  
  [***]
  
  [***]
  
  [***]Operating
  Income
  
  [***]
  
  [***]
  
  [***]Share
  of Operating Income (Loss) Due
  
  
  
  [***]
  
  [***]Payment
  to SYNTA
  
  
  
  [***]
  
  [***]Net
  Amount Retained/Received
  
  
  
  [***]
  
  [***]
   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 4-4


6.             Audit
Rights.Each Party shall
keep and maintain for [***] years complete and accurate records of all
Commercialization Expenses incurred in connection with the Co-Commercialized
Products and of Net Sales of Co-Commercialized Products (Co-Commercialization
Net Sales) in the Co-Commercialization Territory in sufficient detail to allow
confirmation of same by an independent certified public accountant.  Each Party (the Auditing Party) shall have
the right for a period of [***] years after such Commercialization Expenses and
Co-Commercialization Net Sales are reconciled in accordance with the applicable
section of the Co-Commercialization Agreement, to appoint at its expense an
independent certified public accountant reasonably acceptable to the other
Party (the Audited Party) to audit the relevant records of the Audited Party
and its Affiliates to verify that the amount of such Commercialization Expenses
and Co-Commercialization Net Sales are correctly determined.  The Audited Party or its Affiliates shall
each make its records available for audit by the independent certified public
accountant during regular business hours at such place or places where such
records are customarily kept, upon [***] days written notice from the Auditing
Party.  Such audit right shall not be
exercised by an Auditing Party more than [***] in any Calendar Year and no
twelve (12) month period may be audited more than [***].  The independent certified public accountant
will only disclose the results (any sums either over/under paid) of such audit
to the Auditing Party and no other details. 
In the event there was an error in the amount of such Commercialization
Expenses and Co-Commercialization Net Sales reported by the Audited Party
hereunder, (a) if the effect of the error resulted in an underpayment, the
Audited Party shall promptly, on receipt of an invoice, make payment to the
Auditing Party of the underpayment amount and (b) if the effect of the
error resulted in an overpayment, the Auditing Party shall promptly on receipt
of an invoice make payment to the Audited Party of the overpayment amount.  The Auditing Party shall bear the full cost
of such audit unless such audit discloses an error by the Audited Party of at
least [***] percent ([***]%) of the aggregate amount of the Operating Income
(Loss) in any Calendar Year subject to such audit, in which case the Audited
Party shall reimburse the Auditing Party for all costs incurred by the Auditing
Party in connection with such audit.   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 4-5


SCHEDULE 5  FORM OF PRESS RELEASE    GSK and Synta Pharmaceuticals Announce Development and
Commercialization Collaboration for STA-4783 in Oncology  LONDON, UK and LEXINGTON, MA  October 10, 2007
GlaxoSmithKline (GSK) (LSE: GSK; NYSE: GSK) and Synta Pharmaceuticals Corp.
(NASDAQ: SNTA) today announced the execution of a global collaboration
agreement for the joint development and commercialization of STA-4783, a
first-in-class, small-molecule, oxidative stress inducer that is entering Phase
3 clinical development for the treatment of metastatic melanoma.  Under
the terms of the agreement, the companies will share responsibility for
development and commercialization of STA-4783 in the U.S. and GSK will have
exclusive responsibility for development and commercialization of STA-4783
outside the U.S.  Synta will receive an
upfront cash payment of $80 million. 
Synta will also be eligible to receive potential milestone payments of
up to $135 million for events leading to approval of STA-4783 in metastatic
melanoma, further development and regulatory milestones of up to $450 million
across various indications and up to $300 million in potential commercial
milestone payments based on achieving certain net sales thresholds.Synta
will continue to fund all development for metastatic melanoma in the US and the
companies will share responsibility and costs for development of STA-4783 in
other indications.  Synta and GSK willjointly
commercialize STA-4783 in the U.S. with Synta receiving a tiered profit share
based on levels of annual net sales.The parties will share development costs outside of the
US and Synta will receive double-digit tiered royalties on net sales.  In addition, GSK may, subject to Syntas
agreement, purchase, up to $45 million of Syntas common stockupon thefuture achievement of specified development and
regulatory milestones.  The
agreement is subject to antitrust clearance by the U.S. government under the
Hart-Scott-Rodino Act.Common stock purchases may be subject to approval of
Syntas shareholders if required under the rules and regulations of The
NASDAQ Stock Market.  GSK
is an established global leader in the pharmaceutical industry with a strong
commitment to oncology as a franchise, said Safi Bahcall, Ph.D., President and
Chief Executive Officer, Synta.  GSK and
Synta have a shared vision for the development and commercialization of
STA-4783 in a range of potential indications, beginning with metastatic
melanoma where a phase 2b study with STA-4783 in combination with paclitaxel
has shown doubling of progression free survival    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 5-1


compared
to paclitaxel alone.  We are confident
that this agreement will allow STA-4783 to achieve its full potential as a
novel therapeutic option for treating cancer.  This
agreement confirms GSKs growing status as a world leader in the development of
new oncology medicines for use in the treatment, prevention and supportive care
of cancer patients.  It further
strengthens our late stage oncology pipeline, which currently includes ten
Phase 3 programs, and also demonstrates our commitment to identifying compounds
that have the potential to deliver real benefit to patients, said Moncef
Slaoui, Chairman R&D, GSK.  The data
we have seen from the Phase 2 trials conducted by Synta have given us
confidence in the potential of STA-4783 as a novel means of treating metastatic
melanoma, a disease for which there is high unmet medical need.  We
are pleased to establish this alliance with GSK, a company with a long history
of success in launching and marketing important and innovative new drugs, said
Martin Williams, Senior Vice President and Chief Business Officer, Synta.  GSK shares our enthusiasm and commitment to
developing this first-in-class compound. 
Together we expect to bring STA-4783 more quickly to more patients and
to build a U.S. sales and marketing organization at Synta in collaboration with
a world leader.  Conference Call [details
to be added]  About
STA-4783 STA-4783
is a novel, injectable, investigational drug candidate that kills cancer cells
by elevating oxidative stress levels beyond a breaking point, triggering
programmed cell death. In preclinical models STA-4783 showed potent killing of
a broad range of cancer cell types at high doses, and an ability to strongly
enhance the efficacy of certain chemotherapy agents, with minimal additional
toxicity, at moderate doses.  In
a recent 21-center, double-blind, randomized, controlled Phase 2b clinical
trial in 81 patients with metastatic melanoma, STA-4783 in combination with
paclitaxel met the primary endpoint - doubling the median time patients
survived without their disease progressing - compared to paclitaxel alone
(p=0.035). STA-4783 is now entering a pivotal, confirmatory Phase 3 clinical
trial in metastatic melanoma.  Phase 2 trials in other indications, and in
combination with other agents, are planned.  STA-4783 has received Fast
Track designation from the FDA for development in metastatic melanoma.  About
Metastatic Melanoma Melanoma, the most
deadly form of skin cancer, arises from melanocytes, the pigment-producing
cells of the skin. According to the American Cancer Society, melanoma accounts
for approximately five percent of all skin cancers but causes about 75% of all
skin cancer-related deaths. An estimated 60,000 people will be diagnosed and
nearly 8,200 people will die from melanoma this year in the U.S. alone. If
diagnosed and surgically removed while localized in the outermost skin layer,
melanoma is potentially curable; however, for patients with metastatic disease
the prognosis is poor, with limited available treatments and an expected
survival of only six to nine months.  The incidence of
melanoma has increased more rapidly than any other cancer during the past ten
years. The FDA has not approved a novel, small molecule drug for the treatment
of metastatic melanoma in over 30 years.   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    Sched. 5-2


About
Oxidative Stress and Apoptosis Oxidative stress in cells is the presence of elevated levels of reactive
oxygen species (ROS) such as oxygen radicals and hydrogen peroxide. ROS can be
generated by many stimuli, including ordinary cell metabolism, exposure to heat
or radiation, or attack by bacteria or viruses. 
Normal cells have a strong anti-oxidant capacity that regulates the
levels of ROS.  Cancer cells, however,
typically operate at a much higher level of oxidative stress than normal cells
and have a greatly diminished anti-oxidant capacity. This diminished capacity
to clear ROS leaves them vulnerable to further increases in oxidative
stress.   When ROS levels exceed a
critical threshold, continued survival of the cell becomes unsustainable and
programmed cell death (apoptosis) is initiated.  In a series of in vitro and in vivo experiments, STA-4783 has been shown
to rapidly cause a dramatic increase in the level of ROS inside cancer cells
and induce apoptosis.  At similar doses
and exposure, STA-4783 has little to no impact on non-cancer cells.  Elevated oxidative stress induces apoptosis through the mitochondrial
pathway.  In addition to potent induction
of oxidative stress and apoptosis in cancer cells as a single agent, STA-4783
has been shown to enhance the activity of other anti-cancer agents that act
through the mitochondrial pathway.  These
include commonly used chemotherapies such as paclitaxel and docetaxel.  Oxidative stress induction represents a novel anti-cancer strategy  a
novel way of differentiating, and selectively killing, cancer cells vs. normal
cells.  About
GSK GlaxoSmithKline, one of the worlds leading research-based pharmaceutical
and healthcare companies, is committed to improving the quality of human life
by enabling people to do more, feel better and live longer.   For information about GSK visit the company
website at www.GSK.com  About Synta Pharmaceuticals Synta Pharmaceuticals Corp. is a biopharmaceutical
company focused on discovering, developing, and commercializing small molecule
drugs to extend and enhance the lives of patients with severe medical
conditions, including cancer and chronic inflammatory diseases. Synta has a
unique chemical compound library, an integrated discovery engine, and a diverse
pipeline of clinical- and preclinical-stage drug candidates with distinct
mechanisms of action and novel chemical structures. All Synta drug candidates
were discovered and developed internally. For more information, please see
www.Syntapharma.com.  Synta
Safe Harbor Statement This
media release contains forward-looking statements including statements relating
to the potential value of payments that may be received pursuant to the
agreement with GSK, the potential equity investments by GSK, and the
anticipated progress and development of STA-4783, including the timing of
clinical trials. Such forward-looking statements can be identified by the use
of forward-looking terminology such as will, would, should, expects, anticipates,
intends, plans, believes, may, estimates, predicts, projects, or
similar expressions intended to identify forward-looking statements. Such
statements, reflect our current views with respect to future events and are
based on assumptions and subject to risks and uncertainties    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 5-3


that
could cause actual results to differ materially from those expressed or implied
by such forward-looking statements, including those described under Risk
Factors in our Annual Report on Form 10-K for the year ended December 31,
2006 as filed with the Securities and Exchange Commission. Synta undertakes no
obligation to publicly update forward-looking statements, whether because of
new information, future events or otherwise, except as required by law.  GSK
Safe Harbor Statement  ###   Contacts Synta:Synta
  Pharmaceuticals Corp.
  
  Synta
  PR Agency   Contacts GSK:GSK   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 5-4


SCHEDULE 6  MATERIAL TERMS TO BE INCLUDED IN CO-COMMERCIALIZATION AGREEMENT  The Co-Commercialization
Agreement to be negotiated by the Parties shall contain the following material
terms.  Capitalized terms used in this Schedule
6and not otherwise defined have the meanings given to them in the
Agreement.  1.             Co-Commercialization Rights.  (a)           SYNTA and GSK hereby acknowledge and
agree that the overall objectives of conducting SYNTA Co-Commercialization
Activities and GSK Co-Commercialization Activities in the Co-Commercialization
Territory are to reach a broad customer audience, ensure consistency of the
marketing message for Co-Commercialized Products, and maximize the commercial
opportunity for the Co-Commercialized Products. 
All Promotional Efforts shall be conducted in such markets as the JCC
reasonably considers to be appropriate to maximize the success of such
Co-Commercialized Product based on objective, quantifiable information and
market research data with the objectives of allocating to each of SYNTA and GSK
target audience and accounts from which each such Party will have the
opportunity to maximize Net Sales.  (b)           Until the first to occur of: (i) [***]
Calendar Years after [***] in the [***] of [***]; (ii) achievement of
[***] in the [***] of at least [***] dollars ($[***]); (iii) in [***], the
[***] of a [***] in the [***]; or, (iv) [***], the [***] by [***] of a
[***] with the [***] as a [***] (the Initial Co-Commercialization Period),
GSK shall be responsible for promoting such Co-Commercialized Product to [***]
in the Co-Commercialization Territory and SYNTA shall be responsible for
promoting such Co-Commercialized Product to [***], unless otherwise agreed
between the Parties.  After such Initial
Co-Commercialization Period, SYNTA may provide up to [***] percent ([***]%) of
the promotional effort, with GSK providing the balance.  As these responsibilities are split, the
objective of the Parties will be to ensure there is clarity in accountability
(for example, SYNTA may take responsibility for [***] or GSK may take
responsibility for [***]).  The
allocation of promotional effort between the Parties for [***] Indications
shall be determined by the JCC, depending upon the Indications that have
obtained Commercialization Regulatory Approval. 
Neither Party shall engage a Third Party to perform activities with
respect to its promotional responsibilities unless the other Party has already
declined to assume such extra effort and obtain reimbursement therefor.  Notwithstanding the foregoing, if GSK launches
more than [***] other [***] products in the same [***] month period during
which the [***] of a Co-Commercialized Product in the [***] occurs, then,
[***], SYNTA may be permitted to provide further Promotional Efforts for
certain target audiences.  (c)           SYNTA and GSK shall use a coordinated
sales force to conduct Promotional Efforts for each Co-Commercialized
Product.  In connection therewith,
neither Party will, without the other Partys prior written consent, [***] for
a Co-Commercialized Product if [***] is [***] that is [***] to be [***] with
the [***] of the Co-Commercialized   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 6-1


Product.
For clarity, the Parties acknowledge that a [***] of the [***] as a
Co-Commercialized Product may be [***] by the [***] of its [***] or [***].  SYNTA and GSK hereby agree that each Party
shall be responsible for ensuring that its Representatives conduct Promotional
Efforts with respect to Co-Commercialized Products in a manner consistent with
the Product Co-Commercialization Plan and/or the decisions of the JCC.  Notwithstanding the foregoing, in performing
their respective Promotional Efforts hereunder, each of the Parties agrees to (i) [***]
with an [***] for the [***] and [***] as described in the Product Co-Commercialization
Plan and (ii) [***] its [***] and [***] for its [***].  All SYNTA Representatives will have been
recruited by SYNTA [***], and all GSK representatives will have been recruited
by GSK [***].  2.             Commercialization Efforts.  Each Party shall use Commercially Reasonable
Efforts to execute its obligations under each Product Co-Commercialization
Plan, consistent with the applicable Commercialization Budget and in accordance
with all Applicable Laws, and to cooperate diligently with each other in
carrying out such Product Co-Commercialization Plan.  3.             Product Co-Commercialization
Plan and Commercialization Budget.  (a)           Preparation of Annual Plan and
Budget.  The Parties will jointly
prepare the Product Co-Commercialization Plan for each Co-Commercialized Product
for all cancer Indications for the Co-Commercialization Territory.  Each such Product Co-Commercialization Plan
shall be reviewed and approved by the JCC; provided, that, each such Product
Co-Commercialization Plan shall be consistent with the Partys rights under the
Agreement. Each Product Co-Commercialization Plan and Commercialization Budget
shall be submitted to the JCC for review and approval by a date to be
established by the JCC, taking into account GSKs and SYNTAs annual budget
planning calendars, but no later than [***] of each Calendar Year.  It is contemplated that each Product
Co-Commercialization Plan and Commercialization Budget will become more
comprehensive as the Commercialization of the applicable Co-Commercialized
Product evolves.  (b)           Changes to Plans/Budgets.  Any significant change in a Product
Co-Commercialization Plan or Commercialization Budget during the course of the
year will be communicated promptly to the JCC. 
In addition, the Parties will jointly provide an update on each Product
Co-Commercialization Plan and Commercialization Budget for all Indications to
the JCC no less frequently than semi-annually.  4.             Control
Over Advertising and Promotional Efforts.  (a)           The
JCC shall determine which Party shall be responsible for the creation,
preparation, production and reproduction of all promotional materials, pursuant
to procedures and timelines to be mutually agreed upon, consistent with the
Product Co-Commercialization Plan.  (b)           Neither
Party shall engage in any Advertising or use any label, package, literature or
other written material (other than [***]) in connection with a
Co-Commercialized Product in the Co-Commercialization Territory, unless the
specific form and content thereof is approved by the JCC.    Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 6-2


(c)           General Public Relations on the part
of either Party need not be [***] by the [***], but all representations and
statements pertaining to Co-Commercialized Products that appear in [***] of
SYNTA or GSK and include subject matter not previously approved by the JCC shall
be subject to the approval of the JCC.  (d)           All Advertising and Promotional
Efforts undertaken by either Party hereto shall be undertaken in good faith
with a view towards maximizing the sales of the applicable Co-Commercialized
Product.  (e)           Except with the prior written consent
of the other Party, neither Party shall use the name of the other Party or any
Affiliate of the other Party in Advertising, Promotional Efforts or General
Public Relations except in materials approved by the JCC.  (f)            [***]
recommendations will be developed by the JCC and approved by the JSC.GSK shall have the sole
responsibility for conducting all billing and collections for Co-Commercialized
Products.  (g)           GSK shall have sole responsibility
for arranging for the [***] and [***] of Co-Commercialized Products.  (h)           Each Party shall [***] certify to the
other Party that its field force (including persons responsible for managing
the field force) is properly trained with respect to both Product information
and compliance with Applicable Laws.  5.             Sales Efforts in the
Co-Commercialization Territory.  (a)           As part of each Product
Co-Commercialization Plan for the Co-Commercialization Territory, the JCC shall
determine the targeted level of sales of the applicable Co-Commercialized Product
for the Commercialization target audience for the Calendar Year covered by such
Product Co-Commercialization Plan.  (b)           The Product Co-Commercialization Plan
shall include the total number of Representatives and the allocation between
the Parties of such Representatives required to provide Promotional Efforts to
the defined target audience.  The
Co-Commercialized Product shall be included in each Partys respective sales
incentive bonus program for the corresponding Representatives, with specified
links to sales performance.  6.             Training Program.  GSK shall (a) develop a training program
for the promotion of all Co-Commercialized Products and (b) train all
Representatives of both Parties to be used for the conduct of Promotional
Efforts for Co-Commercialized Products in the Co-Commercialization Territory
prior to commencement of Promotional Efforts. 
The Parties [***] on an [***] to [***] and all such [***] at a [***]
that is [***].  [***] either Party may
[***] to [***] unless such [***] the training program described in this Section 6.  Except as provided herein, it is agreed that
for the Product specific training, the internal costs and the out-of-pocket
costs of such training programs (including, without limitation, the
out-of-pocket costs of the development, production, printing of such training
materials, excluding travel and expenses for Representatives) shall be included
as a Commercialization Expense under this Agreement.   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 6-3


7.             Co-Commercialization
Mechanism.  (a)           Sales.  All sales of Co-Commercialized Products in
the Co-Commercialization Territory shall be booked by GSK.  If, during the term of the
Co-Commercialization Agreement, SYNTA receives orders from customers for a
Co-Commercialized Product, it shall refer such orders to GSK.  (b)           Processing of Orders for
Co-Commercialized Products.  (i)            All
orders for Co-Commercialized Products received by SYNTA during the term of the
Co-Commercialization Agreement shall be executed by GSK in a reasonably timely
manner consistent with the general practices applied by it in executing orders
for other pharmaceutical products sold by it or its Affiliates.  (ii)           The
Parties shall comply with all Applicable Laws in selling any Co-Commercialized
Products.  8.             Transition of Certain Activities.  At any time after the [***] anniversary of
the date of [***] of a Product and the receipt by SYNTA of [***] in the U.S.
Territory of a product [***], SYNTA may request, by providing not less than
[***] days written notice (the Commercialization Activities Transition Notice),
that GSK transition to SYNTA certain GSK Co-Commercialization Activities;
provided, that SYNTA agrees that certain GSK Co-Commercialization Activities
must be transitioned in bundles as follows: (a) [***] to [***] for [***]
of the [***], then [***] must also [***] for [***] of [***] (for both [***])
and [***], (b) [***] to [***] for [***], then [***] must also [***] for
[***] and (c) [***] to [***] for [***], then [***] must [***] with [***]
to [***].  As soon as practicable, but in
any event on or before [***] days from the date of the Commercialization
Activities Transition Notice, the Parties shall prepare and submit to the JCC
for its review and approval a mutually acceptable transition plan (the Commercialization
Transition Plan) which shall describe with reasonable specificity the steps to
be followed, and the timelines applicable to, the transitioning of such GSK
Co-Commercialization Activities in order to transition such activities to SYNTA
as promptly as possible.  Notwithstanding
the foregoing, any transition of GSK Co-Commercialization Activities (i) shall
be [***] to [***] to [***], that [***] is able to [***] in a [***] of the same,
(ii) shall not [***] in any [***] in the [***] of the [***] and (iii) shall
not be [***] to the [***], including [***]. 
In no event will GSK transfer responsibility to SYNTA for sales force
training, sales information and [***]. 
Notwithstanding anything in this Section 8, if SYNTA exercises its
Development Opt-Out Right with respect to any Indication at any time, then this
Section 8 shall have no further force and effect and there shall be no
transition to SYNTA of any GSK Co-Commercialization Activities hereunder with
respect to any Product and/or any Indication.  10.           Sales Information Integration.  The Parties will strive to establish a
transparent and compatible sales reporting system for Co-Commercialized
Products to facilitate call planning and Representatives activities, and all
costs related to such integration shall be Commercialization Expenses;
provided, that this [***] to the [***] of such a [***].   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.    Sched. 6-4


11.           Product Recalls.  In the event that any Regulatory Authority
issues or requests a recall or takes similar action in connection with a
Co-Commercialized Product, or in the event a Party reasonably believes that an
event, incident or circumstance has occurred that may result in the need for a
recall, market withdrawal or
other corrective action regarding a Co-Commercialized Product, such Party shall
promptly advise the designated officer of the other Party thereof by telephone
or facsimile and GSK shall be responsible for such recall, market withdrawal or
other corrective action; provided, that all expenses incurred in connection
with any such recall, market withdrawal or corrective action (including,
without limitation, expenses for notification, destruction and return of the
affected Product and any refund to customers of amounts paid for such
Co-Commercialized Product) shall be a Commercialization Expense.  12.           Miscellaneous.  Other customary terms, including confidentiality,
indemnification and termination.      Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.   Sched. 6-5


SCHEDULE 7  PRINCIPLES USED FOR DETERMINING DEVELOPMENT COSTS  In
calculating Development Costs, the following principles shall apply:  1.There shall be no double
counting of any costs or expenses, and to the extent a cost or expense has been
included in one category or sub-category, it shall not be included in another;
similarly, to the extent any revenue has been taken into account in one
category or sub-category, it shall not be taken into account in another.  2.When allocating costs and
expenses under this Agreement, each Party shall utilize the same policies and
principles as it utilizes consistently within its group and business units when
making internal cost allocations, as previously discussed and agreed with the
JDC.  3.All costs and expenses shall
be determined, and all calculations shall be made, in accordance with GAAP or
IFRS, as applicable.   Portions
of this Exhibit were omitted and have been filed separately with the Secretary
of the Commission pursuant to the Companys application requesting confidential
treatment under Rule 24b-2 of the Securities Exchange Act of 1934.