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Exhibit 10.42

MARKETING, DISTRIBUTION AND DEVELOPMENT AGREEMENT

BY AND BETWEEN

GILEAD SCIENCES, INC.

AND

CUBIST PHARMACEUTICALS, INC.

January 6, 2001

[*]=CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

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TABLE OF CONTENTS

 
   
  PAGE

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ARTICLE 1   DEFINITIONS   1   1.1   "Affiliate"   1   1.2   "Bacteremia"   1  
1.3   "CAP"   1   1.4   "Change in Control"   1   1.5   "Clinical Transfer
Price"   1   1.6   "Commercial Launch"   1   1.7   "Commercialize"   1   1.8  
"Commercially Reasonable Efforts"   2   1.9   "Compulsory License"   2   1.10  
"Confidential Information"   2   1.11   "Control"   2   1.12   "Core IV
Products"   2   1.13   "Core Licensed Products"   2   1.14   "Core Trials"   2  
1.15   "CPMP"   2   1.16   "cSST"   2   1.17   "Cubist Development Plan"   2  
1.18   "Cubist Diligence Obligation"   2   1.19   "Cubist Know-How"   2   1.20  
"Cubist Marks"   2   1.21   "Cubist Patent"   2   1.22   "Cubist Technology"   2
  1.23   "cUTI"   2   1.24   "Daptomycin"   3   1.25   "Daptomycin Product"   3
  1.26   "Daptomycin-Derived Product"   3   1.27   "Development Subcommittee"  
3   1.28   "Diligence Obligation"   3   1.29   "Directly Competitive Product"  
3   1.30   "Dollar"   3   1.31   "Drug Approval Application"   3   1.32   "EC"  
3   1.33   "EMEA"   3   1.34   "Endocarditis"   3   1.35   "Enterococcal
Infection"   3   1.36   "FDA"   3   1.37   "Force Majeure   3   1.38   "Free
Sales Certificate"   3   1.39   "Gilead Development Plan"   4   1.40   'Gilead
Diligence Obligation"   4   1.41   "Gilead Indemnifiable Technology"   4   1.42
  "Gilead Indemnifiable Technology Losses"   4   1.43   "Gilead Marks"   4  
1.44   "Gilead Project Know-How"   4   1.45   "Gilead Project Patent"   4   1.46
  "Gilead Project Technology"   4

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  1.47   "Gilead Territory"   4   1.48   "HAP"   4   1.49   "Incremental Product
Development Costs"   4   1.50   "IND"   4   1.51   "Information"   4   1.52  
"Infringement"   4   1.53   "IV Product"   4   1.54   "Joint Invention"   5  
1.55   "Joint Patent"   5   1.56   "Licensed Product"   5   1.57   "Lilly"   5  
1.58   "Lilly License"   5   1.59   "Loss"   5   1.60   "MAA"   5   1.61  
"Marketing Subcommittee"   5   1.62   "MSL"   5   1.63   "NDA"   5   1.64  
"Necessary"   5   1.65   "Net Sales"   5   1.66   "Oral Product"   6   1.67  
"Oral Product Fee"   6   1.68   "Other Licensee"   6   1.69   "Patent"   6  
1.70   "Permitted Sublicense"   6   1.71   "Phase I Clinical Trial"   6   1.72  
"Phase II Clinical Trial"   6   1.73   "Phase III Clinical Trials"   6   1.74  
"Phase IIIB Clinical Trials"   6   1.75   "Phase IV Clinical Trials"   6   1.76
  "Price Approval"   7   1.77   "Primary Endpoint"   7   1.78   "Refund Event"  
7   1.79   "Regulatory Approval"   7   1.80   "Regulatory Authority"   7   1.81
  "Related Gilead Know-How"   7   1.82   "Related Gilead Project Patent"   7  
1.83   "Related Gilead Technology"   7   1.84   "ROFR Territory"   7   1.85  
"Steering Committee"   7   1.86   "Supply Agreement"   7   1.87   "Term"   7  
1.88   "Third Party Royalties"   7   1.89   "Third Party"   7   1.90   "Transfer
Price"   7   1.91   "Valid Claim"   7 ARTICLE 2   MANAGEMENT   8   2.1   General
  8   2.2   Steering Committee   8   2.3   Formation of Subcommittees   9   2.4
  Project Coordinators   11

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  2.5   Collaboration Guidelines   11   2.6   Accounting   11 ARTICLE 3  
DEVELOPMENT   11   3.1   Cubist Development, Development Plan, and Diligence
Obligation   11   3.2   Gilead Development Plan   13   3.3   Responsibilities of
the Development Subcommittee during Development   13   3.4   Modification of
Clinical Trials; Incremental Product Development Costs   13   3.5  
Determination of Cubist Diligence   14 ARTICLE 4   REGULATORY   15   4.1  
General   15   4.2   Free Sales Certificates; Ownership of Regulatory Approvals
  15   4.3   Gilead Access to Cubist and Other Licensee Information   16   4.4  
Cubist and Other Licensee Access to Gilead Information   17   4.5   Adverse
Event Reporting   17   4.6   Communications   17   4.7   Applications for
Regulatory Exclusivity   17   4.8   Recalls and Voluntary Withdrawals   17   4.9
  Label   18 ARTICLE 5   COMMERCIALIZATION; DILIGENCE   19   5.1   Right   19  
5.2   Responsibilities of the Marketing Subcommittee during Commercialization  
19   5.3   Marketing Plan   19   5.4   Activities by MSLs in Gilead Territory  
19   5.5   Diligence Obligation   20   5.6   Determination of Gilead's Diligence
  21   5.7   Diversion of Resources for Directly Competitive Product   21   5.8
  Discounting   22   5.9   Gilead Compliance   22 ARTICLE 6   LICENSE; RIGHTS OF
FIRST REFUSAL; EXCLUSIVITY   22   6.1   Patent Licenses to Gilead   22   6.2  
Patent Licenses to Cubist   22   6.3   Nonexclusive Know-How License to Gilead  
23   6.4   Nonexclusive Know-How License to Cubist   23   6.5   Rights of First
Refusal and Negotiation   23   6.6   Exclusivity   24   6.7   Trademark License
  24   6.8   Third Party Technology   25     (a) Required   25     (b) Desirable
  25   6.9   Sublicensed Technology   25   6.10   Related Gilead Technology.  
26   6.11   Sublicensing   26   6.12   Use of Patents and Know-How   26   6.13  
Field   26 ARTICLE 7   MANUFACTURE AND SUPPLY   26   7.1   Supply by Cubist   26
  7.2   Transfer Price   27 ARTICLE 8   COMPENSATION   28   8.1   License Fee  
28   8.2   Milestone Payments   28

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  8.3   Royalties   29   8.4   Term of Royalties   30   8.5   Third Party
Royalties and Other Payments   30   8.6   Royalty Payments and Reports   30  
8.7   Taxes   30   8.8   Blocked Currency   30   8.9   Foreign Exchange   30  
8.10   Payments to or Reports by Affiliates   31   8.11   Late Payments.   31
ARTICLE 9   INTELLECTUAL PROPERTY   31   9.1   Ownership of Inventions   31  
9.2   Prosecution of Patents   31   9.3   Patent Term Extensions.   32   9.4  
Non-Patent Regulatory Exclusivity   32   9.5   Infringement of Patents by Third
Parties   32   9.6   Infringement of Third Party Rights   34   9.7   Royalty
Reduction   35   9.8   Patent Marking   35   9.9   Selection and Registration of
Product Trademarks   35   9.10   Infringement of Trademarks by Third Parties  
36   9.11   Patent Oppositions   36     (a) Third Party Patent Rights   36    
(b) Parties' Patent Rights   36     (c) Noncontravention   36   9.12   Lilly
License   36 ARTICLE 10   REPRESENTATIONS AND WARRANTIES   36   10.1   Mutual
Representations and Warranties   36   10.2   Cubist   37   10.3   Disclaimer  
38   10.4   No Other Representations   38 ARTICLE 11   INDEMNIFICATION   38  
11.1   Indemnification by Cubist   38   11.2   Indemnification by Gilead   38  
11.3   Procedure   38   11.4   Insurance   39   11.5   No Application to Third
Party Infringement Claims   39   11.6   Limitation of Liability   39 ARTICLE 12
  RECORDS; PUBLICATIONS   39   12.1   Records   39   12.2   Publications   40
ARTICLE 13   CONFIDENTIALITY   40   13.1   Treatment of Confidential Information
  40   13.2   Authorized Disclosure   41   13.3   Publicity   41 ARTICLE 14  
TERM AND TERMINATION   41   14.1   Term   41   14.2   Termination by Gilead   41
  14.3   Termination for Breach   42   14.4   Cubist Rights upon Certain
Terminations of the Agreement or as to Certain Licensed Products   42

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  14.5   Gilead Rights upon Certain Terminations   43   14.6   Survival   43  
14.7   Clarification with respect to Supply Agreement.   43   14.8   Repurchase
of Inventory   43 ARTICLE 15   DISPUTE RESOLUTION   44   15.1   Disputes   44  
15.2   Governing Law; Judicial Resolution   44   15.3   Patent and Trademark
Dispute Resolution   44   15.4   [*] Resolution of Certain Disputes   44 ARTICLE
16   MISCELLANEOUS   45   16.1   Entire Agreement; Amendment   45   16.2   Force
Majeure   45   16.3   Notices   45   16.4   Maintenance of Records   46   16.5  
No Strict Construction   46   16.6   Assignment   46   16.7   Performance by
Affiliates   46   16.8   Counterparts   47   16.9   Further Actions   47   16.10
  Severability   47   16.11   Headings   47   16.12   No Waiver   47

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CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY BRACKETS,
HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.

MARKETING, DISTRIBUTION AND DEVELOPMENT AGREEMENT

    THIS MARKETING, DISTRIBUTION AND DEVELOPMENT AGREEMENT (the "Agreement") is
made effective as of the 6th day of January, 2001 (the "Effective Date") by and
between GILEAD SCIENCES, INC., a Delaware corporation having its principal place
of business at 333 Lakeside Drive, Foster City, CA 94404 ("Gilead"), and CUBIST
PHARMACEUTICALS, INC., a Delaware corporation having its principal place of
business at 24 Emily Street, Cambridge, Massachusetts 02139 ("Cubist"). Cubist
and Gilead are sometimes referred to herein individually as a "Party" and
collectively as the "Parties", and references to "Gilead" and "Cubist" shall
include their respective Affiliates.

RECITALS

    WHEREAS, Cubist has in-licensed and continues to develop a proprietary
compound known under the generic name of daptomycin;

    WHEREAS, Cubist is currently conducting clinical trials of an intravenous
formulation of daptomycin for the treatment of various gram-positive bacterial
infections in humans, and is evaluating an oral formulation of daptomycin in
preclinical studies;

    WHEREAS, Gilead possesses extensive capabilities in the development,
promotion and marketing of anti-infective pharmaceutical products in Europe and
desires to seek regulatory approval for and market daptomycin in Europe; and

    WHEREAS, Gilead desires to obtain the exclusive right to develop and
commercialize daptomycin in the European Community and certain additional
countries, and Cubist desires to grant Gilead such rights in such countries all
as set forth below;

    NOW THEREFORE, based on the foregoing premises and the mutual covenants and
obligations set forth below, the Parties agree as follows:

ARTICLE 1
DEFINITIONS

    The following terms shall have the following meanings as used in this
Agreement:

    1.1 "Affiliate" shall mean, except as provided below, an entity that,
directly or indirectly, through one or more intermediaries, controls, is
controlled by or is under common control with Cubist or Gilead.

    1.2 "Bacteremia" shall mean the treatment of a blood-borne infection caused
by any bacteria.

    1.3 "CAP" shall mean the treatment of community acquired pneumonia.

    1.4 "Change in Control" shall mean that a Third Party shall have become the
beneficial owner of securities representing [*] or more of the aggregate voting
power of the then outstanding voting securities of Cubist, or any sale by Cubist
of all or substantially all of Cubist's assets.

    1.5 "Clinical Transfer Price" shall have the meaning assigned such term in
Section 7.2.

    1.6 "Commercial Launch" shall mean the first sale of a Licensed Product to a
Third Party in a given country.

    1.7 "Commercialize" shall have the meaning assigned such term in Section 5.1
and "Commercialization" shall be interpreted accordingly.

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    1.8 "Commercially Reasonable Efforts" shall mean, with respect to a Party's
obligation under this Agreement to develop or commercialize Licensed Product,
the level of efforts required to carry out such obligation in sustained manner
consistent with the efforts a similarly situated biopharmaceutical company
devotes to a product of similar market potential, profit potential or strategic
value resulting from its own research efforts, based on conditions then
prevailing.

    1.9 "Compulsory License" shall mean a compulsory license under any Cubist
Patent obtained by a Third Party through the order, decree, or grant of a
governmental authority of competent jurisdiction, authorizing such Third Party
to manufacture, use, sell, offer for sale or import a product competitive with a
Licensed Product in one or more countries within the Gilead Territory.

    1.10 "Confidential Information" shall mean all Information, and other
information and materials, received by either Party from the other Party
pursuant to this Agreement, other than that portion of such information or
materials which:

    (a) is publicly disclosed by the disclosing Party, either before or after it
becomes known to the receiving Party;

    (b) was known to the receiving Party, without obligation to keep it
confidential, prior to when it was received from the disclosing Party;

    (c) is subsequently disclosed to the receiving Party by a Third Party
lawfully in possession thereof without obligation to keep it confidential;

    (d) has been publicly disclosed other than by the disclosing Party and
without breach of an obligation of confidentiality with respect thereto; or

    (e) has been independently developed by the receiving Party without the aid,
application or use of Confidential Information, as demonstrated by competent
written proof.

    1.11 "Control" shall mean possession of the ability to grant a license or
sublicense as provided for herein without violating the terms of any agreement
or other arrangement with any Third Party.

    1.12 "Core IV Products" shall mean those IV Products whose primary
therapeutic indication is CAP or cSST.

    1.13 "Core Licensed Products" shall mean those Licensed Products whose
primary therapeutic indication is CAP or cSST.

    1.14 "Core Trials" shall mean the clinical trials listed on Exhibit A under
the title "Core Trials."

    1.15 "CPMP" shall mean the Committee for Proprietary Medicinal Products,
which represents the medicine authorities of the European Community member
states.

    1.16 "cSST" shall mean the treatment of complicated skin and soft tissue
bacterial infection.

    1.17 "Cubist Development Plan" shall have the meaning assigned such term in
Section 3.1.

    1.18 "Cubist Diligence Obligation" shall have the meaning assigned such term
in Section 3.5.

    1.19 "Cubist Know-How" shall mean all Information which is [*].
Notwithstanding anything herein to the contrary, Cubist Know-How shall exclude
Information [*].

    1.20 "Cubist Marks" shall mean (i) all [*] listed at Exhibit B; (ii) the
[*]; and (iii) any other [*] that the Parties may agree in writing to designate
for [*].

    1.21 "Cubist Patent" shall mean any Patent which (i) covers [*]; and (ii) is
[*], including [*].

    1.22 "Cubist Technology" shall mean all Cubist Patents and Cubist Know-How.

    1.23 "cUTI" shall mean the treatment of complicated urinary tract
infections.

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    1.24 "Daptomycin" shall mean the compound set forth and identified as the
primary daptomycin molecule on Exhibit C, [*] of such compound, which [*], and
all [*] of such primary daptomycin molecule, [*].

    1.25 "Daptomycin Product" shall mean any pharmaceutical composition
containing Daptomycin, but only if such pharmaceutical composition is formulated
for use for oral delivery [*] or for delivery via injection [*], and that [*];
provided, however, that in any event, [*] is developing pursuant to its [*] for
development of [*] shall be deemed to be a Licensed Product.

    1.26 "Daptomycin-Derived Product" shall mean any pharmaceutical
composition   [*] and that [*], but excluding Daptomycin Products.

    1.27 "Development Subcommittee" shall have the meaning assigned such term in
Section 2.3(a).

    1.28 "Diligence Obligation" shall mean the Gilead Diligence Obligation
and/or the Cubist Diligence Obligation.

    1.29 "Directly Competitive Product" shall mean any antibiotic in any
formulation marketed and sold (i) primarily for [*] (provided that this
clause (i) shall apply solely for the purpose of determining whether a product
is competitive with [*] Licensed Product and shall not apply for the purpose of
determining whether a product is competitive with any Licensed Product other
than [*]), (ii) primarily to [*] in humans, and (iii) for [*] approved by a
Regulatory Authority in the Gilead Territory including, as the primary
indication for the product, an indication that is also included on the label
approved by a Regulatory Authority in the Gilead Territory for any Licensed
Product. The Parties shall, at the time Cubist or Gilead commences Phase III
Clinical Trials for an Oral Product that is a Licensed Product, modify this
definition by mutual agreement to accommodate products competitive with such
Oral Product, considering the terms of this Section 1.29 as guiding principles
(it being understood that [*] of such Oral Product may not necessarily be [*]).
If the Parties do not agree, the issue shall be submitted for resolution [*] as
provided in Section 15.4.

    1.30 "Dollar" shall mean a United States dollar, and "$" shall be
interpreted accordingly.

    1.31 "Drug Approval Application" shall mean an application for Regulatory
Approval required before commercial sale or use of a Licensed Product as a drug
in a regulatory jurisdiction, including without limitation an NDA filed in the
United States.

    1.32 "EC" shall mean the European Community.

    1.33 "EMEA" shall mean the European Medicines Evaluation Agency, or any
successor thereto, which coordinates the scientific review of human
pharmaceutical products under the centralized licensing procedures of the
European Community.

    1.34 "Endocarditis" shall mean the treatment of inflammation of the heart
and/or its valves resulting from a bacterial infection.

    1.35 "Enterococcal Infection" shall mean the treatment of enterococcal
bacterial infections.

    1.36 "FDA" shall mean the United States Food and Drug Administration, or any
successor thereto.

    1.37 "Force Majeure" shall mean any event beyond the control of the relevant
Party, including, without limitation, fire, flood, earthquakes, riots, strikes,
epidemics, war (declared or undeclared and including the continuance, expansion
or new outbreak of any war or conflict now in existence), embargoes and
governmental actions or decrees.

    1.38 "Free Sales Certificate" shall mean market approval sufficient for the
manufacture, distribution, use and sale of Licensed Products outside of the
United States which can be obtained primarily on the basis of U.S. FDA, EMEA or
other European Regulatory Approval and without the conduct of additional
clinical trials, and shall include both market approvals referred to commonly as

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"free sales certificates" and similar market approvals or certificates referred
to by other names, provided that such similar market approvals or certificates
do not impose a substantially greater burden on the applicant than those market
approvals commonly referred to as "free sales certificates."

    1.39 "Gilead Development Plan" shall have the meaning assigned such term in
Section 3.2.

    1.40 "Gilead Diligence Obligation" shall have the meaning assigned such term
in Section 5.6.

    1.41 "Gilead Indemnifiable Technology" shall have the meaning assigned such
term in Section 9.6(d)(ii).

    1.42 "Gilead Indemnifiable Technology Losses" shall have the meaning
assigned such term in Section 9.6(d)(ii).

    1.43 "Gilead Marks" shall mean (i) all [*] listed at Exhibit D as it may be
updated from time to time; (ii) any [*] in connection with Licensed Products in
the Gilead Territory; and (iii) any other [*] that the Parties may agree in
writing to designate for [*].

    1.44 "Gilead Project Know-How" shall mean all Information that (i) Gilead
[*], (ii) covers the [*] and (iii) is [*]. Gilead Project Know-How shall exclude
Information [*]. Gilead Project Know-How shall include any [*] that the Parties
agree in writing to include in the Gilead Project Know-How [*].

    1.45 "Gilead Project Patent" shall mean any Patent that (i) claims [*]
(ii) covers the [*], (iii) is [*], and (iv) is [*]. Gilead Project Patents
include Gilead's interest in [*] that the Parties agree in writing to include in
the Gilead Project Patents [*].

    1.46 "Gilead Project Technology" shall mean the Gilead Project Know-How and
Gilead Project Patents.

    1.47 "Gilead Territory" shall mean the countries listed in Exhibit E and any
other country that is added to the Gilead Territory pursuant to Section 6.5(a),
and the possessions and territories of each such country.

    1.48 "HAP" shall mean the treatment of hospital-acquired pneumonia.

    1.49 "Incremental Product Development Costs" shall mean the costs attributed
to the implementation of a Proposed Modification, as determined by the Steering
Committee pursuant to Section 3.4.

    1.50 "IND" shall mean an Investigational New Drug Application as defined in
the United States Food, Drug and Cosmetic Act and applicable regulations
promulgated thereunder by the FDA or the equivalent application to the
equivalent agency in any other country or group of countries, the filing of
which is necessary to commence clinical testing of Licensed Product in humans in
a particular jurisdiction.

    1.51 "Information" shall mean (i) techniques and data specifically relating
to development, manufacture, use or sale of Licensed Products, including, but
not limited to, inventions, practices, methods, knowledge, know-how, skill,
experience, test data including pharmacological, toxicological and clinical test
data, analytical and quality control data, regulatory submissions,
correspondence and communications, marketing, pricing, distribution, cost,
sales, manufacturing, patent and legal data or descriptions and
(ii) compositions of matter, assays and biological materials specifically
relating to development, manufacture, use or sale of Licensed Products.

    1.52 "Infringement" shall have the meaning assigned in Section 9.5.

    1.53 "IV Product" shall mean any Daptomycin Product formulated for
intravenous delivery, including without limitation the formulation described by
the specifications set forth in a letter that Cubist has provided to Gilead
prior to the Effective Date.

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    1.54 "Joint Invention" shall have the meaning assigned in Section 9.1.

    1.55 "Joint Patent" shall have the meaning assigned such term in
Section 9.2.

    1.56 "Licensed Product" shall mean all Daptomycin Products, and all
Daptomycin—Derived Products that become Licensed Products pursuant to
Section 6.5(b).

    1.57 "Lilly" shall mean Eli Lilly and Company.

    1.58 "Lilly License" shall mean that certain Licensing Agreement between
Cubist and Lilly dated October 6, 2000, which restated the prior agreement
between such parties dated November 7, 1997, as amended.

    1.59 "Loss" shall have the meaning assigned such term in Section 11.1.

    1.60 "MAA" shall mean an application filed with the EMEA for regulatory
approval to market and sell Licensed Products in the European Union, or an
application filed through the mutual recognition procedures in the European
Union having a similar purpose to the NDA in the United States.

    1.61 "Marketing Subcommittee" shall have the meaning assigned such term in
Section 2.3(b).

    1.62 "MSL" shall mean a Cubist employee serving as a medical science liaison
for commercialization of Licensed Products, as provided in Section 5.4.

    1.63 "NDA" shall mean a New Drug Application for Regulatory Approval filed
in the United States.

    1.64 "Necessary" shall have the meaning assigned such term in
Section 6.8(a).

    1.65 "Net Sales" shall mean, with respect to a particular time period, the
amount billed by Gilead, its Affiliates and Permitted Sublicensees for sales of
Licensed Products made in such time period to a Third Party less:

    (i)  discounts, including cash and quantity discounts, charge-back payments
and rebates granted to managed health care organizations or to federal, state
and local governments, their agencies, purchasers and reimbursers or to trade
customers;

    (ii) credits or allowances actually granted upon claims, damaged goods,
rejections or returns of such Licensed Products, including recalls;

    (iii) freight, postage, shipping, transportation and insurance charges
actually allowed or paid for delivery of Licensed Products; and

    (iv) taxes (other than income taxes), duties or other governmental charges
levied on, absorbed or otherwise imposed on sale of such Licensed Products,
including without limitation value-added taxes, or other governmental charges
otherwise measured by the billing, as adjusted for rebates and refunds.

    If Gilead sells Licensed Products in the form of a combination product
containing one or more active ingredients in addition to Daptomycin (which may
be either combined in a single formulation or packaged as separate formulations
sold as a single package), Net Sales for such combination product will be
calculated by multiplying actual Net Sales of such combination product by the
fraction A/(A+B) where A is the invoice price of the Licensed Product if sold
separately, and B is the total invoice price of the other active ingredient or
ingredients in the combination, if sold separately. If, on a country-by-country
basis, the other active ingredient or ingredients in the combination are not
sold separately in said country, Net Sales for the purpose of determining
royalties of the combination product shall be calculated by multiplying actual
Net Sales of such combination product by the fraction A/C where A is the invoice
price of the Licensed Product if sold separately, and C is the invoice price of
the combination product. If, on a country-by-country basis, the Licensed Product
is not sold

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separately in said country, Net Sales for the purposes of determining royalties
of the combination product shall be determined by the Steering Committee in good
faith on the basis of the fair market value of the Licensed Product.

    Notwithstanding the foregoing, amounts received by Gilead, its Affiliates or
Permitted Sublicensees for the sale of Licensed Products among Gilead, its
Affiliates and Permitted Sublicensees for resale shall not be included in the
computation of Net Sales hereunder.

    For purposes of this definition and the other provisions of this Agreement,
no distributor of Gilead that sells a Licensed Product shall be deemed to be a
Permitted Sublicensee of Gilead unless expressly so agreed in writing by the
Parties. If any distributor of Licensed Products makes any payment to Gilead,
its Affiliates or Permitted Sublicensees in consideration of being a distributor
of any Licensed Product, which payment would not, but for the provisions of this
sentence, be included in the definition of Net Sales, then the amount of such
payment to Gilead, its Affiliates or Permitted Sublicensees shall be included in
Net Sales in the quarter in which Gilead, its Affiliates or Permitted
Sublicensees received such payment for purposes of calculating the royalty due
to Cubist pursuant to Article 8.

    1.66 "Oral Product" shall mean any Daptomycin Product formulated for oral
delivery, [*].

    1.67 "Oral Product Fee" shall have the meaning assigned such term in
Section 8.1(b).

    1.68 "Other Licensee" shall mean any Third Party to whom Cubist has granted
or grants a license and/or sublicense to develop or commercialize a Licensed
Product.

    1.69 "Patent" shall mean (i) unexpired letters patent (including inventor's
certificates) which have not been held invalid or unenforceable by a court of
competent jurisdiction from which no appeal can be taken or has been taken
within the required time period, including without limitation any substitution,
extension, registration, confirmation, reissue, re-examination, renewal or any
like filing thereof and (ii) pending applications for letters patent, including
without limitation any provisional, converted provisional, continued prosecution
application, continuation, divisional or continuation-in-part thereof.

    1.70 "Permitted Sublicense" shall have the meaning assigned such term in
Section 6.11.

    1.71 "Phase I Clinical Trial" shall mean those trials on sufficient numbers
of normal volunteers and patients that are designed to establish that a
pharmaceutical product is safe for its intended use, and to support its
continued testing in Phase II Clinical Trials.

    1.72 "Phase II Clinical Trial" shall mean those trials on sufficient numbers
of patients that are designed to establish the safety, dosage and biological
activity of a pharmaceutical product for its intended use, and to define
warnings, precautions and adverse reactions that are associated with the
pharmaceutical product in the dosage range to be prescribed.

    1.73 "Phase III Clinical Trials" means those trials on sufficient numbers of
patients that are designed to establish that a drug is safe and efficacious for
its intended use, and to define warnings, precautions and adverse reactions that
are associated with the drug in the dosage range to be prescribed, and
supporting Regulatory Approval of such drug or label expansion of such drug.

    1.74 "Phase IIIB Clinical Trials" means product support clinical trials of a
Licensed Product (i.e., a clinical trial which is not required for receipt of
Regulatory Approval but which may be useful in providing additional drug profile
data) commenced before receipt of Regulatory Approval in the country where such
trial is being conducted.

    1.75 "Phase IV Clinical Trials" means product support clinical trials of a
Licensed Product commenced after receipt of Regulatory Approval in the country
where such trial is being conducted.

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    1.76 "Price Approval" shall mean, with respect to any country in which the
price at which Gilead sells Licensed Product must be approved by a governmental
authority for reimbursement or payment purposes, the receipt of approval by the
applicable governmental authority with respect to such price.

    1.77 "Primary Endpoint" shall mean, with respect to a clinical trial, the
point at which equivalence to the comparator agent has been achieved with
respect to a clinical or microbiological outcome as specified in the protocol
for such trial as set forth in Exhibit A, unless otherwise agreed by the Parties
in writing.

    1.78 "Refund Event" shall have the meaning assigned such term in
Section 8.1(c).

    1.79 "Regulatory Approval" shall mean any approvals (including supplements,
amendments, pre- and post-approvals and Price Approvals), licenses,
registrations or authorizations of any national, supra-national (e.g., the
European Commission or the Council of the European Union), regional, state or
local regulatory agency, department, bureau, commission, council or other
governmental entity, necessary for the manufacture, distribution, use or sale of
Licensed Products in a regulatory jurisdiction.

    1.80 "Regulatory Authority" shall mean a foreign counterpart of the FDA.

    1.81 "Related Gilead Know-How" shall mean all Information [*] (i) which is
[*], (ii) is [*] and (iii) relates to [*].

    1.82 "Related Gilead Project Patent" shall mean any Patent other than a
Gilead Project Patent which (i) covers [*]; and (ii) is [*], including Gilead's
interest in [* ].

    1.83 "Related Gilead Technology" shall mean the Related Gilead Know-How and
Related Gilead Project Patents.

    1.84 "ROFR Territory" shall mean those countries listed at Exhibit F and
their territories and possessions. The ROFR Territory shall also include [*],
but shall exclude [*] and with respect to which [*]; provided, however, that any
such country that is not included in the ROFR Territory [* ] shall be included
in the ROFR Territory upon and from the date [*].

    1.85 "Steering Committee" shall mean the committee formed as described in
Section 2.2.

    1.86 "Supply Agreement" shall have the meaning assigned such term in
Section 7.1.

    1.87 "Term" shall mean the term of this Agreement.

    1.88 "Third Party Royalties" shall mean royalties payable to any Third Party
as a result of the manufacture, use or sale of Licensed Products pursuant to,
and in accordance with, the provisions of this Agreement or the Supply
Agreement, including without limitation royalties due under the Lilly License.

    1.89 "Third Party" shall mean any entity other than Cubist or Gilead or an
Affiliate of either of them.

    1.90 "Transfer Price" shall mean the price to Gilead for supply of a unit of
Licensed Product manufactured by or for Cubist, which shall be determined
annually in accordance with Section 7.2.

    1.91 "Valid Claim" shall mean (i) an unexpired claim of an issued patent
within Cubist Patents which has not been found to be unpatentable, invalid or
unenforceable by a court or other authority in the subject country, from which
decision no appeal is taken or can be taken; or (ii) a claim of a pending
application within the Cubist Patents, which application claims a first priority
no more than [* ] prior to the date upon which pendency is determined.

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ARTICLE 2
MANAGEMENT

    2.1 General. The Parties desire to establish a committee that will oversee
the Parties' activities under this Agreement, and establish two (2) or more
subcommittees to exchange information regarding, and to discuss the Parties'
development and commercialization of, Licensed Products both within and outside
of the Gilead Territory. Such committee and subcommittees shall have the
responsibilities and authority set forth in this Article 2 and in other
provisions of this Agreement.

    2.2 Steering Committee.

    (a) Formation. Within thirty (30) days after the Effective Date, Cubist and
Gilead shall establish the Steering Committee, which shall have overall
responsibility for the success of the Parties' efforts under this Agreement. The
purposes of the Steering Committee shall be (i) to coordinate the [*], (ii) to
coordinate the Parties' activities hereunder, (iii) to resolve issues that the
subcommittees of the Steering Committee cannot resolve, and (iv) to approve [*],
all based on the principles of prompt and diligent development of the Licensed
Products in the Gilead Territory consistent with good pharmaceutical practices
and the maximization of long-term profits derived from the sale of Licensed
Products in the Gilead Territory.

    (b) Membership. Cubist and Gilead each shall designate three
(3) representatives with appropriate expertise to serve as members of the
Steering Committee. Each Party shall select one (1) person appointed by it to
the Steering Committee to serve as co-chair. Either Party may designate
substitutes for its committee representatives to participate if one or more of
such Party's designated representatives is unable to be present at a meeting. A
Party may replace its representatives serving on the Steering Committee from
time to time by written notice to the other Party specifying the prior
representative(s) to be replaced and the replacement(s) therefor. The Steering
Committee will have the power to form subcommittees in addition to the
Development Subcommittee and the Marketing Subcommittee expressly provided for
in this Agreement, or working groups with appropriate representation from
Cubist, Gilead, their Affiliates, and appropriate Third Parties. The
co-chairpersons shall be responsible for calling meetings, preparing and
circulating an agenda in advance of each meeting, and preparing and issuing
minutes of each meeting within [*] days thereafter.

    (c) Meetings. The Steering Committee shall hold meetings at such times as it
elects to do so, but in no event shall such meetings be held less frequently
than once every [*]. The Steering Committee shall meet alternately at Cubist's
facilities in Cambridge, Massachusetts and Gilead's facilities in Foster City,
California, or at such locations as the Parties may otherwise agree. With the
consent of the representatives of each Party serving on the Steering Committee,
other representatives of each Party or of Third Parties involved in the
manufacture, development or commercialization of the Licensed Products may
attend meetings of the Steering Committee as nonvoting participants. Meetings of
the Steering Committee may be held by audio or video teleconference with the
consent of each Party, provided that at least one (1) meeting per year shall be
held in person. Each Party shall be responsible for all of its own expenses of
participating in the Steering Committee. Meetings of the Steering Committee
shall be effective only if at least two (2) representatives of each Party are
present or participating. The co-chairpersons will alternate responsibility for
preparing minutes of each meeting of the Steering Committee, which minutes will
not be finalized until the co-chairperson that did not prepare such minutes
reviews and confirms the accuracy of such minutes in writing.

    (d) Specific Responsibilities. In addition to its overall responsibility for
overseeing the Parties' activities under this Agreement, the Steering Committee
shall in particular:

     (i) review and comment upon [*], and review and comment upon the [* ];

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    (ii) review strategies for [*];

   (iii) review [*] as it becomes available;

    (iv) review and discuss the Parties' [*];

    (v) review the Parties' [*] with respect to Licensed Products;

    (vi) approve the implementation of [*], and the allocation of [*] for any
approved [*];

   (vii) review and discuss the Parties' [*] relating to Licensed Products; and

  (viii) perform such other functions as appropriate to further the purposes of
this Agreement as determined by the Parties, including the periodic evaluation
of the Parties' performance under this Agreement.

    (e) Limited Authority; Decision-Making.

    (i)  Except with respect to the matters set forth in Section 3.4, the role
of the Steering Committee shall be [*]. The Steering Committee shall serve as a
forum for the sharing of information and for the purpose of preventing, or
informally resolving, disputes between the Parties. However, the Parties intend
to operate [*] in developing and commercializing Licensed Products in their
respective territories. The rights and responsibilities of each Party shall be
governed by this Agreement, including the exhibits hereto, and the Steering
Committee shall not have [*].

    (ii) The Steering Committee shall operate by consensus. With respect to
matters to be discussed by the Steering Committee, the representatives of each
Party shall present a unified position on behalf of such Party. In the absence
of consensus of Steering Committee members with respect to any matter before the
Steering Committee, such matter shall be deemed not to have been approved by the
Steering Committee, and the Parties shall be free to proceed independently as
they see fit (subject always to compliance by the Parties with their respective
obligations under this Agreement). Specifically, in the absence of consensus of
Steering Committee members for [*] that requires Steering Committee approval,
such approval shall be deemed not to have been granted, and the Parties shall
have the rights to proceed independently with respect to [*].

    (f)  Meeting Agendas. Each Party will disclose to the other Party its final
agenda items along with appropriate related Information at least [*] in advance
of each meeting of the Steering Committee.

    2.3 Formation of Subcommittees.

    (a) Development Subcommittee. Within [*] after the Effective Date, the
Parties shall form a subcommittee of the Steering Committee to address
development issues relating to Licensed Products as provided below in Article 3
(the "Development Subcommittee").

    (b) Marketing Subcommittee. At a time designated by the Steering Committee
in advance of Commercial Launch, the Parties shall form a subcommittee of the
Steering Committee to address marketing issues relating to Licensed Products in
the Gilead Territory (the "Marketing Subcommittee").

    (c) Additional Subcommittees. The Steering Committee may form such
additional subcommittees of the Steering Committee as it may deem to be
desirable to address other aspects of Licensed Product development and
commercialization.

    (d) Membership. Cubist and Gilead each shall designate three
(3) representatives with appropriate expertise to serve as members of each of
the subcommittees formed under this

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Section 2.3. One (1) of each Party's members of the Development Subcommittee
shall also be one of such Party's members of the Marketing Subcommittee and
shall have expertise in the area of marketing pharmaceutical products. One of
each Party's members of the Marketing Subcommittee shall also be one of such
Party's members of the Development Subcommittee and shall have expertise in the
area of developing pharmaceutical products. Each Party shall select one
(1) person appointed by it to each such subcommittee to serve as co-chair.
Either Party may designate substitutes for its committee representatives to
participate if one or more of such Party's designated representatives is unable
to be present at a meeting. A Party may replace its representatives serving on a
subcommittee from time to time by written notice to the other Party specifying
the prior representative(s) to be replaced and the replacement(s) therefor. The
co-chairpersons shall be responsible for calling meetings, preparing and
circulating an agenda in advance of each meeting, and preparing and issuing
minutes of each meeting within [*] thereafter.

    (e) Meetings. Each subcommittee shall hold meetings at such times as it
elects to do so, but in no event shall such meetings be held less frequently
than once every [*]. Each subcommittee shall meet alternately at Cubist's
facilities in Cambridge, Massachusetts and Gilead's facilities in Foster City,
California, or at such locations as the Parties may otherwise agree. With the
consent of the representatives of each Party serving on a subcommittee, other
representatives of each Party or of Third Parties involved in the manufacture,
development or commercialization of Licensed Products may attend meetings of the
Steering Committee as nonvoting participants. Meetings of each subcommittee may
be held by audio or video teleconference with the consent of each Party,
provided that at least [*] shall be held in person. Each Party shall be
responsible for all of its own expenses of participating in the subcommittees.
Meetings of each subcommittee shall be effective only if at least two
(2) representatives of each Party are present or participating. The
co-chairpersons will alternate responsibility for preparing minutes of each
meeting of each subcommittee, which minutes will not be finalized until the
co-chairperson that did not prepare such minutes reviews and confirms the
accuracy of such minutes in writing.

    (f)  Specific Responsibilities of the Development Subcommittee. In addition
to its overall responsibility for overseeing the Parties' development activities
under this Agreement, the Development Subcommittee shall in particular:

    (i)  review and comment upon the [*], review and comment upon the [*],
discuss the requirements for [*] and review any [*];

    (ii) work to achieve [*] by coordinating efforts with the Marketing
Subcommittee;

    (iii) evaluate the Parties' [*] to provide for sufficient [*]; and

    (iv) perform such other functions as appropriate to further the purposes of
this Agreement as determined by the Steering Committee.

    (g) Specific Responsibilities of the Marketing Subcommittee. In addition to
its overall responsibility for overseeing the Parties' marketing and
commercialization activities under this Agreement, the Marketing Subcommittee
shall in particular:

    (i)  consider and discuss [*];

    (ii) work to achieve a [*] by coordinating efforts with the Development
Subcommittee, including without limitation coordinating the Parties' efforts
with respect to [*];

    (iii) evaluate the Parties' needs for [*];

    (iv) consider and discuss the Parties' efforts to [*]; and

    (v) perform such other functions as appropriate to further the purposes of
this Agreement as determined by the Steering Committee.

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    (h) Limited Authority; Decision-Making.

    (i)  The role of each subcommittee shall be [*], with the goal of serving as
[*]. However, the parties intend to operate [*] in developing and
commercializing Licensed Products in their respective territories. The rights
and responsibilities of each Party shall be governed by this Agreement,
including the exhibits hereto, and no subcommittee shall have any power to
amend, modify or waive compliance with this Agreement.

    (ii) Each subcommittee shall operate by consensus. With respect to matters
to be discussed by the subcommittee, the representatives of each Party shall
present a unified position on behalf of such Party. Any disagreement among the
members of a subcommittee will be submitted for resolution by the Steering
Committee.

    (i)  Meeting Agendas. Each Party will disclose to the other Party its final
agenda items along with appropriate related Information at least [*] in advance
of each meeting of each subcommittee.

    2.4 Project Coordinators. Each Party will, promptly after the formation of
each subcommittee pursuant to Section 2.3, assign an appropriately expert and
experienced individual to the other Party to facilitate communication and
coordination of activities relating to the development and commercialization of
Licensed Products and to provide support and guidance to the subcommittee (the
"Project Coordinator"). Each Project Coordinator shall be experienced in project
management.

    2.5 Collaboration Guidelines.

    (a) General. In all matters relating to this Agreement, the Parties shall
seek to comply with good pharmaceutical and environmental practices.

    (b) Independence. Subject to the terms of this Agreement, the activities and
resources of each Party shall be managed by such Party, acting independently and
in its individual capacity. The relationship between Cubist and Gilead is that
of independent contractors and neither Party shall have the power to bind or
obligate the other Party in any manner, other than as is expressly set forth in
this Agreement.

    2.6 Accounting. Each Party shall determine Incremental Product Development
Costs and all other costs and expenses that may be shared with or reimbursed to
a Party under this Agreement or the Supply Agreement (including without
limitation the amounts Gilead shall pay to Cubist for supply of Licensed
Products pursuant to the Supply Agreement), if any, using its standard
accounting procedures, consistently applied, to the maximum extent practical as
if such Licensed Product were a solely owned product of the determining Party,
except as specifically provided in this Agreement. The Parties also recognize
that such procedures may change from time to time and that any such changes may
affect the definition of Incremental Product Development Costs and such other
costs and expenses. The Parties agree that, where such changes are economically
material to either Party, adjustments shall be made to compensate the affected
Party in order to preserve the same economics as reflected under this Agreement
under such Party's accounting procedures in effect as of the Effective Date.

ARTICLE 3
DEVELOPMENT

    3.1 Cubist Development, Development Plan, and Diligence Obligation.

    (a) Development Obligation. Subject to the limitations and other provisions
set forth in this Section 3.1, the Parties intend that during the Term, Cubist
shall continue to develop Licensed Products by conducting the Core Trials to
support Regulatory Approval of Core IV Products in the United States.
Additionally, subject to the limitations and other provisions set forth in this

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Section 3.1, Cubist shall use Commercially Reasonable Efforts to conduct (A) a
[*] for the treatment of [*]; (B) a [*] for the treatment of [*]; (C) [*] in
such territories and for such indications [*], having reasonably [*] of the
Development Subcommittee; and (D) such additional clinical trials and
preclinical studies for the IV Product and such additional formulations of
Licensed Products as Cubist determines to conduct, [*] having reasonably [*]
that the Development Subcommittee may make.

    (b) Development Plan. The development activities, including both preclinical
and clinical development activities, that Cubist will conduct for Licensed
Products shall be covered by a development plan that Cubist shall prepare and
submit to the Development Subcommittee for review [*] after the Effective Date
(such plan, the "Cubist Development Plan"). The Cubist Development Plan shall
include at least the [*] in clauses (A), (B) and (C) above in Section 3.1(a).
The Cubist Development Plan shall [*]. Subject to its overall diligence
obligations contained in this Section 3.1, Cubist reserves the right to change
or modify the Cubist Development Plan (except with respect to the [*]) or any of
the preclinical studies or clinical trials (other than the [*]) described in the
Cubist Development Plan in response to (i)   [*], (ii) [*], (iii) [*] or
(iv) [*]. Cubist additionally reserves the right to change or modify any Core
Trial (1) [*] such trial in accordance with the then-current protocol therefor
as a result of [*], or (2) in response to any [*]; provided, however, that
Cubist recognizes that Gilead's efforts to [*] will depend upon [*] and further
provided that the foregoing ability to change or modify a Core Trial shall not
contravene Cubist's obligations to provide [*]. Accordingly, if Cubist has the
right to change or modify a Core Trial pursuant to the foregoing sentence, it
shall so notify Gilead, the Parties shall discuss any proposed modification to
the Core Trial at issue or other alternative arrangement to address the reason
giving rise to Cubist's right to change or modify the Core Trial while providing
for [*] from Cubist to [*], and Cubist shall implement any such proposed
modification or alternative arrangement to which the Parties mutually agree.
Cubist shall modify the Cubist Development Plan from time to time to reflect
timing or protocol changes to the Core Trials or any other trials, and to
reflect additional trials that Cubist conducts or trials Cubist terminates for
any Licensed Product during the Term. Cubist shall also revise the Cubist
Development Plan from time to time to reflect each new indication for or
formulation of Licensed Products that Cubist is developing or plans to develop.
Additionally, [*], Cubist shall update the Cubist Development Plan no later [*]
and submit such plan to the Development Subcommittee for review and comment.
Cubist acknowledges that [*]. Accordingly, Cubist shall use Commercially
Reasonable Efforts to obtain Regulatory Approval of Core IV Products in the
United States.

    (c) Conduct of Clinical Trials Described in Development Plan. Subject to the
provisions of the next sentence and solely with respect to clinical trials that
are not Core Trials, Cubist shall use Commercially Reasonable Efforts to
conduct, and to continue to conduct, if not already begun as of the Effective
Date, all of the clinical trials of Licensed Products described in the Cubist
Development Plan. Gilead acknowledges that it may be consistent with
Commercially Reasonable Efforts for Cubist to suspend or terminate a clinical
trial (other than a Core Trial) or activity referred to in the Cubist
Development Plan [*] including without limitation [*].

    (d) Cubist Trials in Gilead Territory. Any clinical trials conducted by
Cubist may be run at sites within the Gilead Territory, provided that Cubist
first confers with Gilead on the design of any such trials that begin after the
Effective Date, and that the data generated in any such trial shall be used by
Cubist, its Affiliates and Other Licensees solely to support Regulatory Approval
or marketing of Licensed Products outside of the Gilead Territory.

    (e) Oral Product Development. Anything to the contrary in Section 3.1(b) and
3.1(c) notwithstanding, Cubist's diligence obligation with respect to the
development of Oral Products shall be as described in this Section 3.1(e). Until
the Oral Product enters the clinical development phase, Cubist's diligence
obligation hereunder with respect to Oral Products shall be [*] with

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respect to the development of the Oral Product; and Cubist shall provide Gilead
with [*] updates regarding its preclinical development of the Oral Product,
whenever possible, in advance of the Development Subcommittee meetings so that
the Development Committee may discuss such updates. From the date, if ever, that
Cubist decides to commence clinical development of an Oral Product, Cubist's
diligence obligation with respect to such Oral Product shall be to use
Commercially Reasonable Efforts to clinically develop and seek Regulatory
Approval for the Oral Product [*] and to provide Gilead with a clinical data
package sufficient to support Regulatory Approval of the Oral Product in the
Gilead Territory.

    (f)  Determination. Determination of whether Cubist has met its development
diligence obligations pursuant to this Section 3.1 shall be determined solely in
accordance with Section 3.5.

    3.2 Gilead Development Plan. Gilead may, but shall not be obligated to,
conduct [*] for Licensed Products, and such other development activities that
Gilead, in its discretion, deems desirable to [*] for Licensed Products for
which Regulatory Approval has been obtained. Such studies may also include [*]
on Licensed Products. Any development activities that Gilead may conduct for the
Licensed Products shall be set forth in a development plan which Gilead shall
prepare and submit to the Steering Committee for review promptly after Gilead
has designed such trial, but in no event later than the date provided in
Section 3.4 for submission of a protocol for consideration by the Steering
Subcommittee (such plan, the "Gilead Development Plan"). Gilead shall modify the
Gilead Development Plan from time to time to reflect changes to the timing or
protocol for the clinical trials described therein, or to reflect trials that
Gilead determines, in its sole discretion, to conduct or terminate during the
Term. Any clinical trials that Gilead conducts under this Section 3.2 may be run
at sites outside of the Gilead Territory, provided that Gilead confers with
Cubist on the design of any such trial, and that the data generated therein
shall be used by Gilead, its Affiliates or Permitted Sublicensees solely to
support Regulatory Approval in the Gilead Territory. Gilead shall update the
Gilead Development Plan [*] and submit such plan to the Development Subcommittee
for review and comment. [*] shall [*] in connection with any of the activities
reflected in the Gilead Development Plan, except as otherwise provided in
Section 3.4.

    3.3 Responsibilities of the Development Subcommittee during Development. The
Development Subcommittee will review the overall strategy for and design of all
programs under the Cubist Development Plan and the Gilead Development Plan. The
Development Subcommittee shall review and make recommendations to the Steering
Committee whether to approve any proposals by one Party to modify clinical
trials being planned by the other Party, as described in Section 3.4 and prepare
initial estimates and budgets for shared Incremental Product Development Costs
as may be required under Section 3.4.

    3.4 Modification of Clinical Trials; Incremental Product Development Costs.

    (a) Notice. Each Party shall have the right to propose modifications to a
clinical trial for Licensed Products being conducted by the other Party as
provided in this Section 3.4. Each Party shall notify the other Party at least
[*] days before commencing any clinical trial not commenced prior to or on the
Effective Date to support Regulatory Approval of a Licensed Product in such
Party's territory (i.e., the Gilead Territory for Gilead, and all countries
outside the Gilead Territory for Cubist). If such Party giving notice with
respect to a clinical trial it is planning to commence (the "Conducting Party")
has not previously disclosed in the Gilead Development Plan or Cubist
Development Plan, as applicable, the protocol for such trial pursuant to
Section 3.1 or 3.2, then such notice shall be accompanied by such protocol.
Thereafter, the Conducting Party shall, upon request by the other Party (the
"Non-Conducting Party"), provide such relevant information as the Non-Conducting
Party may reasonably request within [*] days after receiving notice from the
Conducting Party under this Section 3.4 to enable the Non-Conducting Party to
determine its

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interest in using data obtained in such clinical trial to support a filing for
Regulatory Approval of or another regulatory filing for Licensed Products in the
Non-Conducting Party's territory.

    (b) Response. If the Non-Conducting Party is interested in so using such
data, and if the Non-Conducting Party desires to propose a modification to a
protocol for a clinical trial to be conducted by the Conducting Party, the
Non-Conducting Party shall so notify the Conducting Party and specify the
proposed modification to such protocol (the "Proposed Modification") within [*]
days of receiving all information the Conducting Party is required to provide
the Non-Conducting Party pursuant to the foregoing sentence.

    (c) Steering Committee Role; Agreement. The Steering Committee shall confer
regarding such Proposed Modification promptly after the Conducting Party
receives such notice, and the Steering Committee shall, within [*] after the
Conducting Party receives such notice, meet to determine whether implementation
of such Proposed Modification is acceptable to the Parties, and the costs
attributable to implementing the Proposed Modification (the "Incremental Product
Development Costs"). The Steering Committee may request that the Development
Subcommittee develop a budget for implementation of the Proposed Modification
and total Incremental Product Development Costs therefor, and that the
Development Subcommittee make a recommendation of the allocation of such
Incremental Product Development Costs between the Parties based upon [*],
assuming a [*] of such trial. The Development Subcommittee shall also evaluate
the possibility of [* ]. If the Steering Committee approves the Proposed
Modification and agrees upon the appropriate allocation of Incremental Product
Development Costs between the Parties, the Parties may enter into a written
agreement as to the details of the Proposed Modification and Incremental Product
Development Costs associated with such Proposed Modification providing for the
Conducting Party to modify the protocol for the relevant clinical trial to
incorporate the Proposed Modification and amend its development plan hereunder
to reflect such change. If the Steering Committee does not approve the Proposed
Modification, or the Parties do not enter into such an agreement within [*]
after the Steering Committee approves the Proposed Modification, then the
Conducting Party shall have no obligation to modify the protocol for the
relevant clinical trial to incorporate the Proposed Modification and the
Non-Conducting Party shall have no obligation to pay the Incremental Product
Development Costs if the Conducting Party does nonetheless implement the
Proposed Modification. Any such agreement between the Parties may provide for
the Steering Committee to, at least [*], review the Incremental Product
Development Costs actually incurred and to be incurred in connection with a
relevant clinical trial and modify the budget for such Incremental Product
Development Costs as appropriate to reflect the Parties' progress with respect
to such clinical trial.

    (d) Oral Products. In accordance with the rest of this Section 3.4 above,
the Parties recognize that Gilead may request Proposed Modifications to clinical
trials of Oral Products for the purpose of obtaining data to support Regulatory
Approval therefor in the Gilead Territory, and the Parties may enter into an
agreement pursuant to Section 3.4(c). Any agreement between the Parties with
respect to a Proposed Modification of an Oral Product clinical trial may include
[*] with respect to the Oral Product if [*] will be required [*] the Proposed
Modification pursuant to such Agreement.

    3.5 Determination of Cubist Diligence. If Gilead believes that Cubist is not
meeting its diligence obligation pursuant to Section 3.1 (such obligation, the
"Cubist Diligence Obligation") with respect to any Licensed Product, Gilead
shall notify Cubist. Cubist shall respond in writing to Gilead's notice as to
Cubist's activities that it believes meets the Cubist Diligence Obligation with
respect to such Licensed Product as well as the circumstances surrounding
Cubist's development of the Licensed Products within [ *] of Cubist's receipt of
such notice from Gilead. Gilead shall reply to Cubist within [*] after receiving
such written response from Cubist whether, in light of such response, Gilead
continues to believe that Cubist has not met the Cubist Diligence Obligation
with respect to such

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Licensed Product. If, after following the foregoing procedures in this
Section 3.5, the Parties continue to disagree whether Cubist has met the Cubist
Diligence Obligation with respect to such Licensed Product, the Parties shall
[*] to be convened within [*] of such reply from Cubist. [*] shall examine and
discuss for [ *] Cubist's efforts to develop such Licensed Product [*]. After
such examinations and discussions:

    (a) If the Parties are [*] the Cubist Diligence Obligation with respect to
such Licensed Product, then Cubist shall [*] its development of such Licensed
Product [*].

    (b) If Cubist [*] to meet the Cubist Diligence Obligation with respect to
such Licensed Product, then Cubist shall [*] with respect to such Licensed
Product as promptly as is reasonably practicable under the circumstances [*];
provided that if Gilead [*]. If, after following such procedure, the Parties are
in disagreement as to whether Cubist has met the Cubist Diligence Obligation
with respect to such Licensed Product, then Section 3.5(c) shall apply.

    (c) If, after having followed the procedure set forth in Sections 3.5(a) and
3.5 (b), the Parties disagree as to whether [*] describes [*] the Cubist
Diligence Obligation with respect to a particular Licensed Product, then the
Parties shall submit the issue of whether the [*] is sufficient to meet the
Cubist Diligence Obligation with respect to such Licensed Product to [*] by [*].
Such [*] shall determine whether Cubist has met the Cubist Diligence Obligation
with respect to such Licensed Product or whether a [*] is sufficient to enable
Cubist to meet the Cubist Diligence Obligations with respect to such Licensed
Product. If such [*] determines that Cubist has met such Cubist Diligence
Obligation, then Cubist shall be free to proceed with the development of such
Licensed Product [*]; otherwise, such [*] shall formulate [*] to enable Cubist
to meet such Cubist Diligence Obligation and Cubist shall use Commercially
Reasonable Efforts to perform under such [* ].

    (d) In no event shall Cubist be deemed to breach the Cubist Diligence
Obligation with respect to any Licensed Product if any delay, omission or action
by Gilead has contributed to Cubist's delay or failure.

ARTICLE 4
REGULATORY

    4.1 General. Gilead shall devote Commercially Reasonable Efforts to file for
and obtain Regulatory Approval for those Licensed Products in the Gilead
Territory for which Cubist obtains Regulatory Approval in the United States and
regarding which Cubist provides Gilead with clinical data sufficient to support
Regulatory Approval in the Gilead Territory. Notwithstanding anything in this
Agreement to the contrary, Gilead shall not be required pursuant to this
Agreement, but may elect, to [*]. In recognition that Gilead's efforts to obtain
Regulatory Approval for Licensed products in the Gilead Territory will depend
upon its ability to use data relating to Licensed Products generated by Cubist
outside of the Gilead Territory in making regulatory filings within the Gilead
Territory, Cubist shall devote Commercially Reasonable Efforts to obtain
clinical data to support, file for and obtain Regulatory Approval for Core
Licensed Products outside the Gilead Territory in accordance with the provisions
of Article 3.

    4.2 Free Sales Certificates; Ownership of Regulatory Approvals.

    (a) Cubist shall apply for and use Commercially Reasonable Efforts to obtain
Free Sales Certificates for Licensed Products in all countries within the Gilead
Territory where such certificates are available and Gilead requests in writing
that Cubist obtain them. Gilead shall cooperate in all such efforts [*]. Gilead
shall [*] in seeking such Free Sales Certificates. Once Cubist obtains any Free
Sales Certificates for Licensed Products in the Gilead Territory, to the extent
permitted by law, Cubist shall transfer them to Gilead and Gilead shall
thereafter assume all responsibility for communication with Regulatory
Authorities and compliance with law in each

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case in relation to the Free Sales Certificates. In any country in which
transfer of a Free Sales Certificate to Gilead is not permitted by law, Cubist
shall maintain such Free Sales Certificate and reasonably cooperate with Gilead
to effect communications with Regulatory Authorities in connection therewith to
the extent desired and requested by Gilead.

    (b) In all other countries of the Gilead Territory, Gilead shall [*] Drug
Approval Applications and Regulatory Approvals for Licensed Products, and shall
be [* ] responsible for all communications with regulatory authorities in such
countries.

    (c) Gilead shall apply for and use Commercially Reasonable Efforts to obtain
Free Sales Certificates for Licensed Products in all countries outside the
Gilead Territory where such certificates are available and Cubist requests in
writing that Gilead obtain them. Cubist shall cooperate in all such efforts [*].
Cubist shall [*] in seeking such Free Sales Certificates. Once Gilead obtains
any Free Sales Certificates for Licensed Products outside the Gilead Territory,
to the extent permitted by law, Gilead shall transfer them to Cubist and Cubist
shall thereafter assume all responsibility for communication with regulatory
authorities and compliance with law in each case in relation to the Free Sales
Certificates. In any country in which transfer of a Free Sales Certificate to
Cubist is not permitted by law, Gilead shall maintain such Free Sales
Certificate and reasonably cooperate with Cubist to effect communications with
Regulatory Authorities in connection therewith to the extent desired and
requested by Cubist.

    4.3 Gilead Access to Cubist and Other Licensee Information.

    (a) Regulatory Data as of the Effective Date. Cubist will, as soon as
possible after the Effective Date, provide Gilead copies of all regulatory
filings, including without limitation the IND for the IV Product in the United
States, and the results of all clinical and non-clinical testing of IV Products
performed by or on behalf of Cubist or Other Licensees (subject to applicable
restrictions on disclosure of such Information) to the extent that such filings
or information existing prior to the Effective Date has not already been
provided to Gilead prior to the Effective Date.

    (b) Regulatory Data Generated After the Effective Date. During the Term,
Cubist will provide to Gilead for use in Gilead's development efforts relating
to Licensed Products all Information owned or Controlled by Cubist regarding
Licensed Products necessary or useful for making regulatory filings for, or
marketing of, Licensed Products in the Gilead Territory as such Information
becomes available.

    (c) Other Licensee Permission. Cubist shall attempt to obtain from any Other
Licensees permission for Cubist to provide to Gilead any information relating to
Licensed Products that is necessary for Gilead to make regulatory filings for
Licensed Products in the Gilead Territory and that, if such information were
owned or Controlled by Cubist, would be Information that Cubist must provide to
Gilead pursuant to Section 4.3(a) or (b). Cubist shall require Other Licensees
to allow Cubist to disclose to Gilead all information relating to adverse events
that Cubist must report pursuant to Section 4.5. Gilead shall not provide any
Information it receives from Cubist pursuant to this Article 4 (other than
Information relating to adverse events provided by Cubist pursuant to
Section 4.5) to any Permitted Sublicensee unless and until such Permitted
Sublicensee permits Gilead to provide to Cubist any and all information owned or
Controlled by such Permitted Sublicensee that, if such information were owned or
Controlled by Gilead, would be Information that Gilead must provide to Cubist
pursuant to Section 4.4.

    (d) Gilead Use of Information. Gilead shall have a right of access, a right
of reference and the right to use and incorporate all information provided to it
pursuant to this Section 4.3 in its Drug Approval Applications for Regulatory
Approvals of Licensed Products within the Gilead Territory. The Parties shall
discuss, via their participation in the Steering Committee, the form in which
the Parties shall exchange Information pursuant to this Section 4.3 and
Section 4.4.

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    4.4 Cubist and Other Licensee Access to Gilead Information.

    (a) Provision to Cubist. During the Term, Gilead will provide to Cubist for
use in Cubist's development efforts relating to Licensed Products all
Information in Gilead's possession regarding Licensed Products necessary or
useful for making regulatory filings for Licensed Products outside the Gilead
Territory as such Information becomes available. Cubist shall have a right of
access, a right of reference and the right to use and incorporate all
Information provided it pursuant to the foregoing sentence in Drug Approval
Applications in Licensed Products outside of the Gilead Territory. Such rights
shall be transferable solely as provided in Section 4.4(b).

    (b) Sublicensee Permission; Transferability to Sublicensees. Gilead shall
attempt to obtain from any Permitted Sublicensees permission for Gilead to
provide to Cubist any information relating to Licensed Products that is
necessary for Cubist to make regulatory filings for Licensed Products in the
Cubist Territory and that, if such information were owned or Controlled by
Gilead, would be Information that Gilead must provide to Cubist pursuant to
Section 4.4(a). Gilead shall require its Permitted Sublicensees to allow Gilead
to disclose to Cubist all information that Gilead must report pursuant to
Section 4.5. Cubist shall not provide any Information it receives from Gilead
pursuant to this Article 4 (other than Information relating to adverse events
provided by Gilead pursuant to Section 4.5) to any Other Licensee unless and
until such Other Licensee permits Cubist to provide to Gilead any and all
information owned or Controlled by such Other Licensee that, if such information
were owned or Controlled by Cubist, would be Information that Cubist must
provide to Gilead pursuant to Section 4.3.

    4.5 Adverse Event Reporting. The Parties shall report, and take other
actions in relation to, adverse events with Licensed Products to each other in
accordance with a reporting protocol that will be substantially in the form of
the protocol used by Gilead under its relationship with [*].

    4.6 Communications. Except as may be required by law or as contemplated
pursuant to Section 4.2, Cubist shall not communicate regarding any Licensed
Product with any Regulatory Authority having jurisdiction in the Gilead
Territory unless requested to do so by Gilead.

    4.7 Applications for Regulatory Exclusivity. The Parties recognize that
exclusivity rights granted or provided for under regulatory laws of the
countries in the Gilead Territory are likely to be [*] to Licensed Products. To
the extent permitted by law, Gilead shall have the exclusive right to file for,
request and maintain any regulatory exclusivity rights for Licensed Products in
the Gilead Territory, including without limitation regulatory exclusivity rights
based upon an orphan drug designation of a Licensed Product, and to conduct and
prosecute any proceedings or actions to enforce such regulatory exclusivity
rights, and Cubist shall reasonably cooperate with Gilead in such actions [* ].
In countries where Gilead is not entitled to take one or more of the actions
described in the foregoing sentence, then Cubist shall take such actions as
instructed by Gilead and for the benefit of Gilead, [*]. Gilead shall own any
regulatory exclusivity rights in the Gilead Territory where permitted by law.
Cubist hereby grants Gilead the exclusive right to market Licensed Products in
the Gilead Territory under any regulatory exclusivity rights that must be
granted directly to Cubist in a given country in the Gilead Territory.

    4.8 Recalls and Voluntary Withdrawals. The Parties shall exchange their
internal standard operating procedures ("SOPs") as to product recalls reasonably
in advance of Commercial Launch of any Licensed Product in the Gilead Territory.
If either Party becomes aware of information about any Licensed Product
indicating that it may not conform to the specifications for Licensed Product
then in effect pursuant to the Supply Agreement, or that there are potential
adulteration, misbranding and/or other issues regarding safety or effectiveness,
it shall promptly so notify the other Party. The Steering Committee shall meet
to discuss such circumstances and to consider appropriate courses of action,
which courses of action with respect to each recall shall be consistent with the
internal SOP of the Party having the right to control such recall pursuant to
this Section 4.8. Gilead shall have the right to

17

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control, [*], a recall of the Licensed Product in the Gilead Territory, unless
such recall is caused by a Manufacturing Defect (as defined by the Supply
Agreement), in which case [*] shall [*] associated with the recall. Cubist shall
control, [*], all recalls of Licensed Product outside the Gilead Territory.
Gilead shall maintain complete and accurate records of any recall for such
periods as may be required by legal requirements, but in any event for no less
than [* ].

    4.9 Label. To the extent permitted by law, Gilead shall identify Cubist as
the manufacturer or licensor of each Licensed Product on the outside of the
packaging for such Licensed Product in each country of the Gilead Territory in a
manner approved in advance in writing by Cubist, such consent not to be
unreasonably withheld.

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ARTICLE 5
COMMERCIALIZATION; DILIGENCE

    5.1 Right. Gilead shall have the exclusive right to market and
commercialize, including, without limitation, by conducting pre-marketing,
advertising and promotion activities, and sponsoring medical education events,
exhibits and symposia (collectively, "Commercialize") Licensed Products in all
countries of the Gilead Territory during the Term, for its own account (subject
to the [*] under this Agreement), [*] and subject to the participation of the
Cubist MSLs as provided below in Section 5.4.

    5.2 Responsibilities of the Marketing Subcommittee during Commercialization.
The Marketing Subcommittee will review and comment upon the overall strategy and
design of Gilead's marketing efforts under its Marketing Plans.

    5.3 Marketing Plan. No later than [*] before Gilead anticipates the first
Commercial Launch of a Licensed Product anywhere in the Gilead Territory, Gilead
will submit a plan detailing Gilead's projected activities to commercialize
Licensed Products in the Gilead Territory including anticipated budgets (the
"Marketing Plan"), to the Marketing Subcommittee. Thereafter, on or before each
anniversary of the date of the first Commercial Launch of a Licensed Product,
Gilead shall update, revise, and present to the Marketing Subcommittee the
Marketing Plan. The Marketing Plan shall include a description of any
anticipated activities of the MSLs. Cubist may comment upon each version of the
Marketing Plan via its participation in the Marketing Subcommittee. Gilead
reserves the right to modify its Marketing Plan at any time in response to
(i) changes in [* ], (ii) [*], (iii) the feasibility of [*], (iv) changes in the
[*] or (v) any failure [*], subject only to [*]to comment upon such changes and
[*].

    5.4 Activities by MSLs in Gilead Territory.

    (a) MSLs. During the [*] (as defined in Section 5.4(d)), Cubist shall have a
limited right to participate with Gilead in support of certain of Gilead's
Commercialization activities for Licensed Products in the Gilead Territory,
solely as described and permitted in this Section 5.4. Cubist may provide up to
[*] MSLs to participate in such activities throughout the Gilead Territory at
any one time during the [*]; provided, however, that Cubist's rights to so
participate shall expire on a country-by-country basis as provided in
Section 5.4(d), and further provided that Gilead shall have the right, in its
discretion, to allocate the MSLs to participate in such activities in such
country or countries of the Gilead Territory as Gilead may decide. Cubist shall
notify Gilead on or before [*] of each calendar year during the [*] how many
MSLs it will make available in the next calendar year, subject to the
limitations set forth in this Section 5.4. Gilead shall provide to the Cubist
MSLs access to particular facilities in the Gilead Territory for the purposes of
conducting meetings with Gilead representatives, but shall not be required to
provide [*]. Such [*] by Cubist [*] to Gilead in the Gilead Territory, and
Cubist shall be [*], subject to and in accordance with the requirements of the
country in which each Cubist MSL is employed. Each Cubist MSL shall have
language skills appropriate for conducting his or her responsibilities under
this Section 5.4 in the country of the Gilead Territory in which Gilead elects
to place them, and other educational and professional training appropriate for
the conduct of his or her responsibilities in such country. Gilead shall have
the [*] Cubist MSLs proposed by Cubist, and Cubist shall, upon Gilead's request,
[*]. Each [*] shall execute [*] in the form provided by [*].

    (b) Role of Cubist MSLs. The Cubist MSLs shall, [ *] relating to Licensed
Products: (i) to [*] of Licensed Products conducted by or on behalf of Gilead in
the Gilead Territory; (ii) to [*] in the Gilead Territory, and [*] in the Gilead
Territory, to the extent consistent with the efforts of Gilead's MSLs providing
[*] in such country; and (iii) to [*], concerning the Licensed Products and
their characteristics. During the [*], Gilead shall provide to each of the
Cubist MSLs a more detailed description of the scope of their [*], and may
update such detailed description from time to time using its [*] judgment,
provided that all activities set forth in any such detailed description

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shall be consistent with this Section 5.4. Except to the extent Gilead
specifically directs in the detailed description of permitted MSL activities
provided pursuant to this Section 5.4(b), Cubist MSLs shall not [*] of Licensed
Products in the Gilead Territory, perform any activities in connection [*],
provide any [ *] with respect to Licensed Products, [*] in the Gilead [*] in
connection with Licensed Products, or perform any [*] or other activities in
relation to Licensed Products in the Gilead Territory. Cubist shall not directly
or indirectly [*] set forth therein. The Cubist MSLs shall [*] conducted in
connection with Licensed Products, [*] with respect to Licensed Products to a
designated Cubist representative who shall in turn provide reports of MSL
activities to each of the Development Subcommittee and the Marketing
Subcommittee, and provide to [*] of Licensed Products. Gilead shall have the
right to [*] from time to time upon [*] notice to Cubist.

    (c) Payment. Gilead shall pay Cubist [*] per MSL [*] to Gilead in the Gilead
Territory during each calendar year during the [*]. Such amount shall be payable
[*] each due within [*] after the end of [*] during the [*], with the first such
payment due within [ *] after the end of the [*] in which the [*] commenced. For
any MSL that Cubist provides pursuant to this Section 5.4 for less than an
entire calendar year, Gilead shall pay Cubist a prorated portion of the
foregoing [*] amount to reflect the portion of such calendar year during which
Cubist [*] such MSL to Gilead (the "Partial Year"), with such amounts payable in
[*] due at the end of [*] during which such MSL was [* ] to Gilead during such
Partial Year.

    (d) Termination of [*]. The "[*]" shall commence [*] prior to the
anticipated date (as determined by the Steering Committee) that the [*] in the
Gilead Territory (the "Commencement Date") and shall expire [*] after [*] in the
Gilead Territory in which Gilead [*] of Licensed Product (the "Expiration
Date"); provided, however, that the [*], and further provided that the [*] shall
terminate [*]. Additionally, during the [*], Cubist's right to provide MSLs to
support Commercialization of Licensed Products shall [*] of a Licensed Product
in the [*] in the Gilead Territory. Anything to the contrary in this Agreement
notwithstanding, (i) Gilead shall [*] in Commercialization of Licensed Products
in each country in the Gilead Territory pursuant to this Section 5.4 [ *] and
(ii) Gilead shall [*].

    5.5 Diligence Obligation. The Parties agree that the primary focus of their
efforts to develop Licensed Products shall be upon IV Products and Oral
Products. Gilead shall use Commercially Reasonable Efforts to Commercialize in
the Gilead Territory both the IV Product, and an Oral Product if Cubist obtains
Regulatory Approval for such a product in the United States and provides a
clinical data package relating thereto that is sufficient to support Regulatory
Approval in the Gilead Territory, in each case following Regulatory Approval of
such Licensed Products in the Gilead Territory. Gilead shall require its
Permitted Sublicensees in the Gilead Territory to use Commercially Reasonable
Efforts to Commercialize such Licensed Products in the Gilead Territory
following Regulatory Approval of such Licensed Products in the Gilead Territory.
Whether Gilead is meeting such Diligence Obligation shall be determined with
respect to each Licensed Product based upon all relevant factors, which may
include without limitation the following factors:

    (a) the level of [*] of such Licensed Product in the [*] in a given calendar
year relative to (i) the level of [*] in the preceding calendar year for such
Licensed Product, and (ii) the level of [*];

    (b) the [*] for such Licensed Product, including whether there is [*];

    (c) the [*] in the Gilead Territory for such Licensed Product;

    (d) the [*] for such Licensed Product in the [*];

    (e) the level of [*] Licensed Product in the Gilead Territory relative to
the level of [*] Licensed Product outside the Gilead Territory, taking into
account differences in Licensed Product [

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* ], the incidence of [*] in such regions, as well as differences in [*] between
the different regions, and such other factors as may be appropriate under the
circumstances;

    (f)  whether [*] with respect to such Licensed Product;

    (g) the [*] for such Licensed Product in a country [*]; and

    (h) Gilead's efforts with respect to [*] in the Gilead Territory and each of
the foregoing factors with respect to the [*].

    In no event shall Gilead's Diligence Obligation with respect to any Licensed
Product be deemed to include a requirement that Gilead [*] in any country.

    5.6 Determination of Gilead's Diligence. If Cubist believes that Gilead is
not meeting its diligence obligation pursuant to Section 5.5 (such obligation,
the "Gilead Diligence Obligation") with respect to any Licensed Product, Cubist
shall notify Gilead. The Parties shall then proceed as provided in Sections
5.6(a) through (d) to determine Gilead's diligence in Commercializing Licensed
Products. Gilead shall [* ] to Cubist's notice [*] with respect to such Licensed
Product as well as [* ] of such Licensed Products within [*] of Gilead's receipt
of such notice from Cubist. Cubist shall [*] with respect to such Licensed
Product. If, after following the foregoing procedures in this Section 5.6, the
Parties continue to disagree whether Gilead has met the Gilead Diligence
Obligation with respect to such Licensed Product, the Parties shall [* ]
Gilead's efforts to Commercialize such Licensed Product in the Gilead Territory
(the "Discussion Period"). After such [* ]:

    (a) If the Parties are in agreement that Gilead is meeting the Gilead
Diligence Obligation with respect to such Licensed Product, then Gilead shall
continue its Commercialization of the Licensed Product without being required to
alter its approach.

    (b) If Gilead [*] with respect to such Licensed Product, then [*] after the
end of the Discussion Period, and shall use [*]; provided that if [*] with
respect to such Licensed Product, then the Parties shall follow the procedure
set forth in the first paragraph of this Section 5.6. If, after following such
procedure, the Parties are in disagreement as to whether Gilead has met the
Gilead Diligence Obligation with respect to such Licensed Product, then
Section 5.6(c) shall apply.

    (c) If, after having followed the procedure set forth in Sections 5.6(a) and
(b), the Parties [*] with respect to such Licensed Product, then the Parties
shall submit the issue of whether Gilead's plan is sufficient to meet such
Diligence Obligation to dispute resolution [*] pursuant to Section 15.4. Such
[*] shall [*]. If such [*] determines that [*] of such Licensed Product pursuant
to its Marketing Plan; otherwise, such [*] shall [*].

    (d) In no event shall Gilead be deemed to breach the Gilead Diligence
Obligation with respect to any Licensed Product if any delay, omission or action
by Cubist or any Cubist MSL has contributed to Gilead's delay or failure.

    5.7 Diversion of Resources for Directly Competitive Product.

    (a) If Gilead Commercializes a Directly Competitive Product in the Gilead
Territory (which Gilead [*]), Gilead shall, within [*] of the commercial launch
of such product, provide to Cubist a statement showing [*] of [*] the date of
the Commercial Launch of such Directly Competitive Product (the "First
Statement"), and shall provide Cubist a statement on [*] thereafter showing the
amount of [*] (each such report a "Subsequent Statement").

    (b) If Cubist disputes the accuracy of the First Statement or any Subsequent
Statement for Licensed Products, the Parties shall confer to determine [*] for
such First Statement or Subsequent Statement. If the Parties cannot agree on [*]
for the relevant statement within [*] after beginning to confer, the [*] for the
purpose of making a determination hereunder.

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    (c) If any Subsequent Statement (including any statement that is modified by
agreement between Gilead and Cubist, or any that is modified [*] shows that
Gilead has [*] from the First Statement, then Gilead shall [*] with respect to
the relevant Licensed Product(s) and Cubist shall [*] with respect to such
Licensed Product(s), with such Licensed Product(s)  [*].

    (d) This Section 5.7 has been agreed upon solely to address Cubist's concern
that Gilead may reduce its commitment to Commercializing Licensed Product(s) if
Gilead is also selling a Directly Competitive Product in the Territory.
Accordingly, this Section 5.7 and its provisions, approach, reasoning, terms,
and percentages shall apply and have relevance only if Gilead is Commercializing
a Directly Competitive Product in the Territory and may not be referred to or
relied upon by either Party, or any court or dispute resolution body, for
purposes of interpreting Gilead's obligations under any other section of this
Agreement, including, without limitation, for determining if Gilead has met the
Gilead Diligence Obligation in Section 5.6.

    5.8 Discounting. Neither Gilead, its Affiliates nor Permitted Sublicensees
shall discount the price of Licensed Products in consideration of any price
increase on, or the receipt of any payment in connection with, a product other
than a Licensed Product, or shall enter into any agreement for such purpose.

    5.9 Gilead Compliance. In connection with any development activities
undertaken by Gilead in connection with any Licensed Product, Gilead shall
comply with all applicable laws and regulations regarding the care and use of
experimental animals, as such laws and regulations are in effect where such
development activities are undertaken. All animals used by Gilead to evaluate
Daptomycin or any Licensed Product shall be provided humane care and treatment
in accordance with the most acceptable veterinary practices.

ARTICLE 6
LICENSE; RIGHTS OF FIRST REFUSAL; EXCLUSIVITY

    6.1 Patent Licenses to Gilead. Subject to the terms and conditions of this
Agreement, Cubist grants to Gilead an exclusive (even as to Cubist except to the
extent provided below) license under the Cubist Patents: (i) [*] Licensed
Products on a worldwide basis for the [*] Licensed Products in the Gilead
Territory; (ii) to [*] Licensed Products in the Gilead Territory; and (iii) to
develop (by conducting preclinical and clinical studies) Licensed Products on a
worldwide basis for the [*] of Licensed Products within the Gilead Territory;
provided, however, that Cubist shall retain the right, including the right to
grant licenses and sublicenses, [*] Licensed Products on a worldwide basis for
the [*] of Licensed Products outside of the Gilead Territory and, solely
pursuant to this Agreement, in the Gilead Territory, and to develop Licensed
Products on a worldwide basis for the [*] of Licensed Products outside of the
Gilead Territory and, solely pursuant to this Agreement, in the Gilead
Territory. Gilead may grant sublicenses under the foregoing license under Cubist
Patents (A) for the purpose of [*] Licensed Products on a worldwide basis for
the [*] of Licensed Products in the Gilead Territory, and (B) for such other
purposes as Cubist may agree pursuant to Section 6.11. All such sublicenses are
subject to the terms and conditions of this Agreement. In addition to any rights
expressly retained by Cubist in the foregoing provisions of this Section 6.1,
Cubist shall retain any and all rights in and to the Cubist Patents that are not
expressly granted to Gilead pursuant to this Section 6.1.

    6.2 Patent Licenses to Cubist. Subject to the terms and conditions of this
Agreement, Gilead grants to Cubist a non-exclusive license under the Gilead
Project Patents: (i) to make and have made Licensed Products on a worldwide
basis for the use, sale, offering for sale and importation of Licensed Products
outside of the Gilead Territory and, solely pursuant to this Agreement including
without limitation the Supply Agreement, in the Gilead Territory; (ii) to use,
sell, offer for sale and import Licensed Products outside of the Gilead
Territory and, solely pursuant to this Agreement including without limitation
the Supply Agreement, in the Gilead Territory; and (iii) to develop Licensed

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Products on a worldwide basis for the use, sale, offering for sale and
importation of Licensed Products outside of the Gilead Territory and, solely
pursuant to this Agreement including without limitation the Supply Agreement,
within the Gilead Territory. Cubist may grant sublicenses under the foregoing
license under Gilead Project Patents. All such sublicenses are subject to the
terms and conditions of this Agreement. Gilead shall retain any and all rights
in and to the Gilead Project Patents that are not expressly granted to Cubist
pursuant to this Section 6.2.

    6.3 Nonexclusive Know-How License to Gilead. Subject to the terms and
conditions of this Agreement, Cubist grants Gilead a [*] to use Cubist Know-How
solely for the purposes of: (i) making and having made (solely as provided in
Article 7 and the Supply Agreement) Licensed Products on a worldwide basis for
the use, sale, offering for sale and importation of Licensed Products in the
Gilead Territory; (ii) using, selling, offering for sale and importing Licensed
Products in the Gilead Territory; and (iii) developing (by conducting
preclinical and clinical studies) Licensed Products on a worldwide basis for the
use, sale, offering for sale and importation of Licensed Products in the Gilead
Territory. Gilead may grant sublicenses under the foregoing license under Cubist
Know-How for the purpose of making and having made (solely as provided in
Article 7 and the Supply Agreement) Licensed Products on a worldwide basis for
the use, sale, offering for sale and importation of Licensed Products in the
Gilead Territory and for such other purposes as Cubist may agree pursuant to
Section 6.11. All such sublicenses are subject to the terms and conditions of
this Agreement. Cubist shall retain any and all rights in and to the Cubist
Know-How that are not expressly granted to Gilead pursuant to this Section 6.3.

    6.4 Nonexclusive Know-How License to Cubist. Subject to the terms and
conditions of this Agreement, Gilead grants Cubist a royalty-free,
non-exclusive, worldwide license, to use Gilead Know-How solely for purposes of
(i) making and having made Licensed Products on a worldwide basis for the use,
sale, offering for sale and importation of Licensed Products outside of the
Gilead Territory and, solely pursuant to this Agreement, including without
limitation the Supply Agreement, in the Gilead Territory; (ii) using, selling,
offering for sale and importing Licensed Products outside the Gilead Territory
and, solely pursuant to this Agreement, including without limitation the Supply
Agreement, in the Gilead Territory; and (iii) developing Licensed Products on a
worldwide basis for the use, sale, offering for sale and importation of Licensed
Products outside of the Gilead Territory and, solely pursuant to this Agreement,
including without limitation the Supply Agreement, within the Gilead Territory.
Cubist may grant sublicenses under the foregoing license under Gilead Project
Know-How. All such licenses are subject to the terms and conditions of this
Agreement. Gilead shall retain any and all rights in and to the Gilead Project
Know-How that are not expressly granted to Cubist pursuant to this Section 6.4.

    6.5 Rights of First Refusal and Negotiation.

    (a) ROFR for Licensed Product in the ROFR Territory. Gilead desires to have
a right of first refusal to develop and Commercialize Licensed Products in the
countries included in the ROFR Territory, which are countries of [*].
Accordingly, Cubist hereby grants Gilead a right of first refusal for [*]
Licensed Products in the ROFR Territory as follows: if Cubist intends to [*] to
[*] in any country [*], Cubist shall so [*] prior to entering into an agreement
with such Third Party with respect to [*] and shall first [*] with respect to
such [*] upon the same [*] with respect to such [*], on the other terms and
conditions set forth in this Agreement, prior to entering into such [*]. If,
within [*] after Cubist shall have made such offer to Gilead, Gilead shall not
have agreed in writing to [*] with respect to such Licensed Product upon such
[*], then Cubist shall be free to enter into such agreement with such Third
Party on such [*] and shall have no further obligation under this Section 6.5(a)
to offer or grant such terms to Gilead in each case for a period of [*] after
the earlier of [*]. Without limiting the generality of the foregoing, this
Section 6.5(a) shall apply if [*] with a Third Party for the [*] in any country
within the ROFR Territory during the Term. If Gilead accepts [*] pursuant to
this Section 6.5(a), then such country shall be included in

23

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the Gilead Territory and excluded from the ROFR Territory for the remainder of
the Term. For purposes of this Section 6.5(a), [*].

    (b) ROFN for [*]. Cubist hereby grants Gilead a right of first negotiation
for [*] in the Gilead Territory and ROFR Territory on the following terms: If
Cubist wishes to contract with a Third Party [*], Cubist shall so notify Gilead,
such notice to reference the relevant [*]. If Gilead requests within [*] after
its receipt of such notice to discuss with Cubist the terms upon which Cubist
would grant Gilead the right to include such [*] within the definition of
Licensed Product (and therefore the licenses of Sections 6.1 and 6.3 pursuant to
this Agreement) and Commercialize, or to otherwise grant Gilead the right to
Commercialize, such  [*], then the Parties shall negotiate in good faith for a
period of [*] such terms. If the Parties are unable to agree upon such terms
within such [*] period, Cubist shall be free for a period of [*] after the end
of the Parties' good faith negotiation period to contract with a Third Party
[*]; provided, however, that in no event shall Cubist enter into an agreement
with a Third Party relating to such [*] (i) prior to the expiration of such [*]
period if Gilead has not notified Cubist of its interest prior to such date, or
(ii) prior to expiration of such [*] period, if the Parties do not reach written
agreement prior to such date. If the Parties reach agreement as to such terms
pursuant to this Section 6.5(b), then the Parties may either agree in writing to
include such [*] within the definition of Licensed Product hereunder or enter
into a separate agreement pursuant to which Cubist would grant Gilead the right
to Commercialize such [*] in the Gilead Territory. Without limiting the
generality of the foregoing, this Section 6.5(b) shall apply if [*] with a Third
Party for the [*] in any country within the Gilead Territory or ROFR Territory.

    6.6 Exclusivity.

    (a) Gilead. In each country of the Gilead Territory, Gilead shall not
market, sell or otherwise distribute any Directly Competitive Product prior to
the [*] anniversary of the Commercial Launch of the Licensed Product with which
such Directly Competitive Product is competitive in such country. Gilead shall
not develop, promote, sell or offer for sale Licensed Products (except in
connection with clinical trials of Licensed Product) outside of the Gilead
Territory. Gilead shall require [*] to make a covenant similar that provided in
this Section 6.6(a) with respect to Licensed Products. Gilead shall be free to
manufacture Licensed Products outside the Gilead Territory solely to the extent
permitted in Article 7 and the Supply Agreement.

    (b) Cubist. Cubist shall not promote, sell, or offer for sale Licensed
Products for use (except in connection with clinical trials of Licensed Product)
within the Gilead Territory. Cubist shall be free to manufacture Licensed
Products in the Gilead Territory in a manner consistent with the licenses
granted to it in Article 6. Cubist shall require [*] to make a covenant similar
to that provided in this Section 6.6(b) with respect to Licensed Products.

    6.7 Trademark License. Cubist hereby grants Gilead an exclusive,
royalty-free license under its entire right, title and interest in and to the
Cubist Marks to use and display the Cubist Marks in connection with the
Commercialization of Licensed Products within the Gilead Territory. Gilead
hereby grants Cubist an exclusive, royalty-free license under its entire right,
title and interest in and to the Gilead Marks to use and display the Gilead
Marks in connection with the Commercialization of Licensed Products outside of
the Gilead Territory. Each Party shall provide the other Party with copies of
any materials containing such other Party's trademarks prior to using or
disseminating such materials, and shall reasonably consider all comments made by
such other Party regarding the use of its trademarks. Neither Party shall use
the other Party's trade names and/or marks in a way which would be confusing or
otherwise adversely affect their value. [*].

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    6.8 Third Party Technology.

    (a) Required. [*] under all intellectual property rights (including without
limitation rights in Patents and trade secrets) that are [*] that may be brought
by a Third Party in connection with the manufacture of Licensed Product by or
for supply to [*], or [*] by [*] in the [*], except that [*] shall have no
obligation under this Section 6.8(a) to the extent that such claims arise or
would arise solely out of the practice of [*], and shall [*], including without
limitation [*] due pursuant to such licenses. [*], its Affiliates, Permitted
Sublicensees and distributors as described in more detail in Section 9.6(d)
against any losses arising from [*] to obtain or maintain any such license.

    (b) Desirable. For each intellectual property right that is [*], either
Party may propose that the Steering Committee consider (i) whether the Parties
should seek a license thereunder to allow either or both Parties to practice
such right in connection with the development, manufacture, use sale, offer for
sale or import of Licensed Products, (ii) how to allocate the costs of obtaining
and maintaining such license between the Parties (taking into account the
Parties' relative interests therein inside and outside of the Gilead Territory)
and (iii) how the Parties should proceed to seek such license. If the Steering
Committee is unable to reach consensus with respect to the seeking of such
license, either Party shall be free to itself seek a license under such right at
its sole cost and expense, with no obligation to make such license or right
available to the other Party.

    6.9 Sublicensed Technology.

    (a) Generally. The licenses granted under this Article 6, to the extent they
include sublicenses of Third-Party technology, shall be subject to the terms and
conditions of the license agreement pursuant to which the sublicense is granted;
provided, however, that if either Party enters into any Third Party license
relevant to the development or commercialization of Licensed Products during the
Term for technology that is desirable for the development and commercialization
of Licensed Products, such Party shall faithfully and timely perform and
discharge its obligations under such Third Party license and shall not permit
any action to be taken or event to occur, in each case, within such Party's
reasonable control, which would give such Third Party the right to terminate
such Third Party license. [*]. If the Party that enters into any such Third
Party license [*] or otherwise [*], it shall promptly notify the other Party.
The Parties shall promptly confer regarding an [*] within [*] by [*]. If the
Party that entered into any such Third Party license [*] within [*], then the
[*] may [*] for [*] for [*] and  [*] shall be [*]. If a good faith dispute
between a Third Party and the Party that entered into a license with such Third
Party about the interpretation of any provision of the agreement governing such
Third Party license, the other Party shall use its Commercially Reasonable
Efforts to ensure that its actions, if any, under this Section 6.9 do not
detrimentally affect the ability of the breaching Party to contest the
interpretation advanced by such Third Party.

    (b) Lilly License.

    (i)  Cubist shall, for the benefit of Gilead, faithfully and timely perform
and discharge its obligations under the Lilly License and shall not permit any
action to be taken or event to occur, in each case, within Cubist's reasonable
control, which would give Lilly the right to terminate the Lilly License.
Notwithstanding the provisions of the foregoing sentence, [*]. If Cubist is
notified or otherwise becomes aware of its material breach of the Lilly License,
it shall promptly notify Gilead. [*]. If Cubist does not perform the agreed upon
remedy of such breach within the designated time, [*].

    (ii) It is agreed and acknowledged that in the event of termination of the
Lilly License, [*].

    (c) Grants Back by Other Licensees. Cubist shall attempt to obtain the
agreement of each of the Other Licensees to grant to Cubist the ability to grant
Gilead a license under such Other

25

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Licensee's Patents and Know-How [*] for Gilead's activities under this
Agreement. Gilead shall attempt to obtain the agreement of its Permitted
Licensees to grant to Gilead the ability to grant Cubist a license under such
sublicensee's Patents and Know-How [*] to make, have made, use, sell, offer for
sale, import or export Licensed Products outside of the Gilead Territory. If
either Party[*], as the case may be, [*] agreement with the Other Licensee or
Permitted Sublicensee, as the case may be; provided, however, that neither Party
shall be [*] in connection with such efforts.

    6.10 Related Gilead Technology.

    (a) Gilead shall inform Cubist of any Related Gilead Know-How (i) that
Gilead is aware is being used by [*] to [*] in or for use in [*], or (ii) that
Gilead wishes for Cubist and its Affiliates and Third Party manufacturers [*],
in the case of clause (ii), as the Parties intend to further provide for in the
Supply Agreement.

    (b) Gilead shall inform Cubist in writing of any [*] (i) that Gilead is
aware covers the [*] in or for use in [*], or (ii) that covers an invention that
Gilead wishes for Cubist and its Affiliates and Third Party manufacturers [*],
in the case of clause (ii), as the Parties intend to further provide for in the
Supply Agreement.

    (c) If Cubist desires to include within the definition of [ *] thereunder
pursuant to [*], as applicable, any particular [*] of which [*], then Cubist
shall so [*] pursuant to [*] and the Parties shall, to the extent that [*] for a
period of [*] upon which [*]. If the Parties [*] for any particular [*] then
such [*] shall be included in the definitions of [*], as applicable, subject to
such agreed [*]. If the Parties [*], then [* ].

    6.11 Sublicensing. In addition to Gilead's rights to sublicense certain of
its rights included in its licenses under the Cubist Patents and the Cubist
Know-How pursuant to Sections 6.1 and 6.3 as provided for in such sections, [*]
pursuant to this Section 6.11 shall be referred to herein as a "Permitted
Sublicensee".

    6.12 Use of Patents and Know-How. Each Party covenants to the other that it
will not practice the Patents or Know-How of the other Party except as expressly
permitted in the licenses granted to it in this Article 6.

    6.13 Field. Notwithstanding anything in this Agreement to the contrary, it
is acknowledged and agreed by the Parties that the licenses granted by Cubist to
Gilead under this Agreement with respect to the Cubist Patents and Cubist
Know-How that are licensed to Cubist pursuant to the Lilly License shall be
solely for application to the treatment of [*].

ARTICLE 7
MANUFACTURE AND SUPPLY

    7.1 Supply by Cubist. As of the Effective Date, Cubist has established
manufacturing arrangements for bulk Daptomycin and finished IV Products through
Third Party suppliers (such Third Parties and any other Third Party supplier of
Licensed Products to Cubist shall be referred to collectively as the "Cubist
Suppliers"). Cubist shall supply to Gilead, and Gilead shall purchase from
Cubist, (i) [*] in the Gilead Territory during the first five (5) years of the
Term, and (ii) [*] of [*] in the Gilead Territory after the first [*] of the
Term, in both cases on the terms and conditions to be set forth in a Supply
Agreement to be added to this Agreement by addendum, which the Parties shall use
their reasonable efforts in good faith to negotiate, execute and deliver within
[*] days after the Effective Date (the "Supply Agreement"). Attached hereto as
Exhibit G is a term sheet that sets forth certain of the terms that the Parties
have agreed to incorporate into the Supply Agreement. Upon execution and
delivery by the Parties of the Supply Agreement, the Supply Agreement shall
supersede all of the terms and provisions of such term sheet.

26

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    7.2 Transfer Price.

    (a) Gilead shall pay to Cubist a transfer price for (i) clinical supply of
Licensed Product to Gilead by Cubist equal to the Clinical Transfer Price, and
(ii) commercial supply of Licensed Product by Cubist to Gilead equal to the
Transfer Price, in each case as determined in accordance with this Section 7.2.

    (b) [*] 2001, a "Clinical Transfer Price" for units of Licensed Product for
clinical supply delivered by Cubist to Gilead and a "Transfer Price" for units
of Licensed Product for commercial supply delivered by Cubist to Gilead, in each
case to apply for the following [*], shall be determined as provided in Sections
7.2(c) and (e) based upon Cubist's [*], for Licensed Product in the [*] period
preceding the time the Transfer Price and Clinical Transfer Price are
determined. The "Clinical Manufacturing Cost" shall be equal to [*], calculated
in accordance with reasonable cost accounting methods that comply with generally
accepted accounting principles. The "Manufacturing Cost" shall be equal to [*],
calculated in accordance with reasonable cost accounting methods that comply
with generally accepted accounting principles. For quantities of Licensed
Product Cubist acquires from a Third Party, Cubist's [*] the calculations of the
Clinical Manufacturing Cost and Manufacturing Cost. The Transfer Price and
Clinical Transfer Price shall [*].

    (c) No later than [*] and no later than [*] thereafter, Cubist shall notify
Gilead in writing of the dollar figures that Cubist proposes to be the Clinical
Transfer Price and Transfer Price, respectively, for units of Licensed Product
delivered in the [*] following the date of such notice. Cubist's notice as to
the Clinical Transfer Price and Transfer Price it proposes shall include [*]
upon which [*], and shall include a [*]. Within [*] of receiving such notice
from Cubist, Gilead shall respond in writing as to whether it (i) [*]
manufactured by Cubist and/or its Affiliates to be [*], or (ii) [*].
Additionally within such time frame, [*].

    (d) If Gilead does not dispute the Clinical Transfer Price or the Transfer
Price proposed by Cubist, then the amounts proposed by Cubist shall be the
Clinical Transfer Price and Transfer Price, respectively, for all units of
Licensed Product manufactured by or for Cubist and/or its Affiliates and
delivered to Gilead in the [*] following the date of the Parties' notices
pursuant to Section 7.2(c).

    (e) Within [*] after the end of each [*] in which Cubist has delivered
Licensed Product to Gilead, Cubist shall notify Gilead in writing of Cubist's
actual Clinical Manufacturing Cost for quantities of Licensed Product delivered
to Gilead as clinical supply in such [*]. If Gilead does not dispute the
Clinical Manufacturing Cost as calculated by Cubist, then [*] any difference
between the Clinical Transfer Price and the Clinical Manufacturing Cost shall,
within [*] after the end of such [*], pay [*] by wire transfer of immediately
available funds to an account designated by such other Party. If Gilead disputes
the Clinical Manufacturing Cost as calculated by Cubist, then such values shall
be determined pursuant to Section 7.2(f) and [ *] any such discrepancy shall,
within [*] after the Independent Accounting Firm as defined in Section 7.2(f)
makes its calculation of such value known to the Parties, pay  [*] by wire
transfer of immediately available funds to an account designated by such other
Party.

    (f)  If Gilead disputes an amount proposed by Cubist to be the Clinical
Transfer Price, Transfer Price, Clinical Manufacturing Price or Manufacturing
Price, then the Steering Committee shall discuss the issues for a period of [*].
If, after such discussions by the Steering Committee, the Parties continue to
disagree on such issue, then the Parties shall submit the issue to Cubist's
independent auditor (currently, Pricewaterhouse Coopers) (the "Independent
Accounting Firm"). The Independent Accounting Firm, using personnel other than
those who perform regular accounting services for Cubist, shall calculate the
disputed value in accordance with the basis specified in Section 7.2(b) based on
[*]. The Parties shall use their commercially reasonable efforts

27

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to cause the Independent Accounting Firm to render its calculation of the
disputed value to the Parties within [*] of the date the Parties submit such
calculation to the Independent Accounting Firm. Neither Party shall [*] the
Independent Accounting Firm. The Parties shall [*] the Independent Accounting
Firm for the purposes described in this Section 7.2(f). The Independent
Accounting Firm's calculation of the disputed value [*].

    (g) If Cubist is to supply Gilead with multiple Licensed Products in a given
[*], then Clinical Transfer Prices, Transfer Prices, Clinical Manufacturing
Costs and Manufacturing Costs shall be determined separately for each Licensed
Product in accordance with this Section 7.2.

    (h) The Supply Agreement shall [*].

ARTICLE 8
COMPENSATION

    8.1 License Fee.

    (a) Within [*] after the Effective Date, Gilead shall pay a license fee for
the IV Product of [*] to Cubist by wire transfer of immediately available funds
into an account designated by Cubist. This license fee shall be nonrefundable
and noncreditable.

    (b) Within [*] after the Effective Date, Gilead shall pay a license fee for
the Oral Product of [*] to Cubist by wire transfer of immediately available
funds into an account designated by Cubist (the "Oral Product Fee"). The Oral
Product Fee shall be subject to [*] in accordance with the provisions of
Section 8.1(c).

    (c) If (I) this Agreement is [*] by Gilead with respect to the Oral Product
pursuant to the provisions of Section 14.2 at any time prior to the [*]
anniversary of the Effective Date, (II) Cubist shall have [*] its [*] with
respect to the Oral Product for a period exceeding [*] (other than on account of
a Force Majeure) at any time prior to the [*], or (III) Cubist has been
determined pursuant to Section 3.5 to have [*] with respect to the Oral Product
at any time [*] in accordance with the following schedule:

    (i)  If a [*] occurs prior to the [*] anniversary of the Effective Date,
[*].

    (ii) If a [*] occurs on or after the [*] anniversary of the Effective Date
but prior to the [*] anniversary of the Effective Date, [*] between [*],
prorated based upon the number of months after the [*] anniversary of the
Effective Date such event occurs (as examples, if such event occurs [*] after
the Effective Date, [*]; if such event occurs [*] after the Effective Date,
[*]).

    Additionally, Gilead shall not [*] with respect to the development of an
Oral Product [*], subject to Section 8.1(d).

    (d) If the [*] leading to a [*] pursuant to Section 8.1(c) was the [*]
referred to in clause (I) of such Section, then Gilead shall have [*] to the
Oral Product. If the [*] leading to a [*] pursuant to Section 8.1(c) was the [*]
referred to in clause (II) or clause (III) of such Section, then Cubist shall
[*] with respect to Oral Products, but Gilead shall [*] pursuant to this
Agreement. If at any time after a [* ] referred to in the foregoing sentence
Cubist wishes to resume development of an Oral Product, Cubist shall so notify
Gilead in writing [*] development of an Oral Product. In such event, Gilead
shall be [*] with respect to an Oral Product [*] after the Resumption Date, but
shall have [*].

    8.2 Milestone Payments. Subject to Section 14.2, in consideration for the
licenses and exclusive rights of this Agreement, Gilead shall make milestone
payments to Cubist based on achievement of IV Product development milestones as
set forth in Section 8.2(a), and based on the achievement of Oral

28

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Product development milestones as set forth in Section 8.2(b). Gilead shall pay
the amounts set forth below within [* ] after Gilead's receipt of notice from
Cubist of the first achievement of the relevant milestone for an IV Product or
an Oral Product, as documented by appropriate written and/or other materials.
Each milestone payment by Gilead to Cubist hereunder shall be paid only once,
and shall be noncreditable and nonrefundable.

    (a) IV Product Development Milestone Payments.

Milestone Event

--------------------------------------------------------------------------------

  Payment Amount
(in millions)

--------------------------------------------------------------------------------

1.   [*] in the following clinical trials included in Exhibit A (defined as [*]
for cSST; and either of the [*] for CAP.   [*] 2.   [*], Protocol Number [*].  
[*] 3.   [*], Protocol Number [*]   [*] 4.   [*], Protocol Number [*].   [*] 5.
  [*], Protocol Number [*].   [*] 6.   [*] for Endocarditis   [*] 7.   [*] for
Endocarditis.   [*] 8.   Completion of the [*] of the following trials:   [*]  
  • [*] for UTI         • [*] for Bacteremia         • [*] for Enterococcal
Infection     9.   [*] for the IV Product.   [*] 10.   [*]   [*] 11.   Patent
issuing from [*] in a country within the Gilead Territory.   [*]

--------------------------------------------------------------------------------

Total Potential IV Product Development Milestone Payments   [*]

    The Parties recognize that the clinical trials, protocol numbers and Primary
Endpoints listed in the milestone events above may change as otherwise permitted
pursuant to this Agreement. The milestone events as defined above shall be
interpreted to apply to the modified clinical trial, protocol number and/or
Primary Endpoint replacing that set forth above.

    (b) Oral Product Development Milestone Payments.

Milestone Event

--------------------------------------------------------------------------------

  Payment Amount
(in millions)

--------------------------------------------------------------------------------

1.   [*] for an Oral Product.   [*] 2.   [*] of an Oral Product.   [*] 3.   [*]
of an Oral Product.   [*] 4.   [*] of an Oral Product.   [*] 5.   [*]   [*]

--------------------------------------------------------------------------------

Total Potential Oral Product Development Milestone Payments   [*]

    8.3 Royalties.

    (a) Royalty. Subject to the other terms and conditions of this Agreement,
Gilead shall pay Cubist a royalty equal to [*] (the "Royalty Rate") of Net Sales
of each Licensed Product sold during each calendar quarter by Gilead, its
Affiliates, or Permitted Sublicensees, less the [*] paid by Gilead for supply of
units of such Licensed Product that are (i) [*] or (ii) [*], but in the case of
clause (ii), [*] Licensed Products, and in each case by Gilead, its Affiliates
or Permitted Sublicensees in such calendar quarter, subject to adjustment
pursuant to this Section 8.3.

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    (b) Royalty Where There Is No Exclusivity. The Royalty Rate shall be reduced
by [*] with respect to Net Sales in any country in the Gilead Territory in which
(i) there is [*] of Licensed Products, or [*] covering [*]; and (ii) there is
[*] in such country.

    (c) Compulsory License. If Gilead learns that a Third Party is seeking a
Compulsory License in any country in the Gilead Territory, Gilead shall use
commercially reasonable efforts to oppose the granting of such Compulsory
License. If either Party learns that a Third Party has obtained a Compulsory
License in any country in the Gilead Territory, such Party shall promptly notify
the other Party of such occurrence. If the [*] by the grantee of the Compulsory
License is [*] than the [*] applicable in such country [*], then the applicable
[*] applicable in such country pursuant to such Compulsory License for so long
as such Compulsory License remains in effect.

    8.4 Term of Royalties. Cubist's right to receive royalties under Section 8.3
shall expire on a country-by-country and product-by-product basis upon the later
of (i) [*] from the Commercial Launch of such Licensed Product in such country;
or (ii) expiration of the last to expire issued Cubist Patent containing a Valid
Claim which would be infringed by the manufacture, use or sale in the Gilead
Territory by Gilead of Licensed Product absent the license granted hereunder.

    8.5 Third Party Royalties and Other Payments. The royalties payable by
Gilead to Cubist under Section 8.3 shall be [*] arising from license or other
agreements entered into by Cubist prior to the Effective Date relating the
manufacture, use, sale, offer for sale or importation of the Licensed Products,
including without limitation [*]; provided, however, that nothing in this
Section 8.5 shall limit the obligation of Gilead to [*] as contemplated by the
Supply Agreement.

    8.6 Royalty Payments and Reports. All amounts payable to Cubist under this
Agreement shall be paid in Dollars within [*] of the end of each calendar
quarter except as otherwise specifically provided herein. Each payment of
royalties owing to Cubist shall be accompanied by a statement, [*] of Licensed
Product, [*] showing deductions provided for in Section 1.65 during such
quarter, the [*] of Licensed Product and Net Sales during such quarter and on a
[*] and the amount of royalty due on such sales. If any royalty reductions are
claimed by Gilead under this Agreement from the full royalty rates set forth in
Section 8.3, then the report shall set forth in detail the claimed reduction and
the related facts.

    8.7 Taxes. Subject to the provisions of Section 8.7(b), Cubist shall be
responsible for any and all taxes levied on account of amounts it receives under
this Agreement.

    (a) Payment Procedure. If Gilead is required by law, rule or regulation to
withhold taxes from such types of payments due Cubist hereunder, Gilead will
(i) deduct those taxes from the remittable amount, (ii) pay the taxes to the
proper taxing authority, and (iii) send evidence of the obligation together with
proof of payment to Cubist within [*] following that payment.

    (b) Gross-Up for Taxes Resulting from Assignment. If as a result of any
assignment of this Agreement from Gilead to an Affiliate of Gilead, or from an
Affiliate of Gilead to another Affiliate of Gilead, including, without
limitation, assignments pursuant to Section 16.6 (collectively, "Gilead
Affiliate Assignment"), the [*] under this Agreement [*].

    8.8 Blocked Currency. In any country where conversion of the local currency
is blocked and such currency cannot be removed from the country, Gilead shall
pay Cubist in local currency by deposit in a local bank designated by Cubist.

    8.9 Foreign Exchange. For the purpose of computing the Net Sales for
Licensed Products sold in a currency other than Dollars, such currency shall be
converted into Dollars as computed in the central Gilead currency conversion
system using the average monthly rate of exchange at the time for such
currencies as retrieved from the on-line edition of the Wall Street Journal (at
http://www.interactive.wsj.com). The currency conversion system used by Gilead
shall be subject to audit by Cubist as described in Section 12.1, and, if not
determined to be a system reflecting a reasonable

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average exchange rate of the currencies in question, shall be modified as
necessary to effect currency conversion at a reasonable average exchange rate.

    8.10 Payments to or Reports by Affiliates. Any payment required under any
provision of this Agreement to be made to either Party or any report required to
be made by any Party shall be made to or by an Affiliate of that Party if
designated in writing by that Party as the appropriate recipient or reporting
entity.

    8.11 Late Payments. Any amounts not paid by Gilead when due under this
Agreement shall be subject to interest from and including the date payment is
due through and including the date upon which Gilead has made a wire transfer of
immediately available funds into an account designated by Cubist at a rate equal
to [*] quoted in the Money Rates section of the on-line edition of the Wall
Street Journal (at http://www.interactive.wsj.com) calculated daily on the basis
of a 365-day year, or similar reputable data source, or, if lower, the highest
rate permitted under applicable law.

ARTICLE 9
INTELLECTUAL PROPERTY

    9.1 Ownership of Inventions. Each Party shall own any inventions made solely
by its employees or agents in their activities hereunder. Inventions hereunder
made jointly by employees or agents of each Party shall be owned jointly by the
parties ("Joint Inventions"). Inventorship shall be determined in accordance
with U.S. patent laws.

    9.2 Prosecution of Patents.

    (a) Cubist Patents. Cubist shall be responsible for the prosecution and
maintenance of the Cubist Patents at [*]. Gilead shall have the right to review
and comment upon such prosecution by Cubist of the Cubist Patents in the
jurisdictions of the Gilead Territory. To that end, Cubist shall furnish Gilead
with copies of each draft submission regarding a Cubist Patent to a patent
authority of any jurisdiction of the Gilead Territory no later than [ *] prior
to the date such submission is proposed to be made, in the state that such
submission is reasonably in at such time (which may, for example, be in the form
of descriptions of experiments and experimental data that may be used to
demonstrate an actual reduction to practice of the relevant invention, which
experiment may be ongoing) and will [* ] thereon. If Gilead does not provide
Cubist with reasonably timely comments, Cubist shall be free to proceed with its
submission or other contemplated action. Cubist will make reasonable efforts to
provide Gilead an update to such draft prior to filing to enable Gilead to
monitor progress and further comment on the draft and shall provide Gilead with
a copy of each submission to a patent authority of a jurisdiction within the
Gilead Territory regarding a Cubist Patent [*] after making such filing. If
Cubist determines in its sole discretion to abandon or not maintain any claim or
patent application within the Cubist Patents anywhere in the Gilead Territory,
then Cubist shall provide Gilead with [* ] prior written notice of such
determination and shall provide Gilead with the opportunity to prosecute and
maintain such claim or patent application in the Gilead Territory on behalf of
Cubist [*]. Cubist shall inform Gilead of any patents, information or proceeding
of which Cubist becomes aware that relate to Cubist Patents that may adversely
impact the validity, title or enforceability of Cubist Patents in the Gilead
Territory.

    (b) Gilead Project Patents. Gilead shall be responsible for the prosecution
and maintenance of the Gilead Project Patents [*]. Cubist shall have the right
to review and comment upon Gilead's prosecution of the Gilead Project Patents in
the jurisdictions outside the Gilead Territory. To that end, Gilead shall
furnish Cubist with copies of each draft submission regarding a Gilead Project
Patent to the patent authority of any jurisdiction outside the Gilead Territory
no later than [*] prior to the date such submission is proposed to be made, in
the state that such draft submission is reasonably in at such time (which may,
for example, be in the form of descriptions of experiments

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and experimental data that may be used to demonstrate an actual reduction to
practice of the relevant invention, which experiment may be ongoing) and will
[*] thereon. If Cubist does not provide Gilead with reasonably timely comments,
Gilead shall be free to proceed with its submission or other contemplated
action. Gilead will make reasonable efforts to provide Cubist an update to such
draft prior to filing to enable Cubist to monitor progress and further comment
on the draft and shall provide Cubist with a copy of each submission made to a
patent authority outside the Gilead Territory regarding a Gilead Project Patent
reasonably promptly after making such filing. If Gilead determines in its sole
discretion to abandon or not maintain any claim or patent application within the
Gilead Project Patents anywhere outside the Gilead Territory, then Gilead shall
provide Cubist with [*] prior written notice of such determination and shall
provide Cubist with the opportunity to prosecute and maintain such claim or
patent application outside the Gilead Territory on behalf of Gilead at [*].
Gilead shall inform Cubist of any patents, information or proceeding of which
Gilead becomes aware that relate to Gilead Project Patents that may adversely
impact the validity, title or enforceability of Gilead Project Patents outside
the Gilead Territory.

    (c) Joint Patents. With respect to Joint Inventions, the Parties shall [*]
covering such Joint Invention (any such patent application and any patents
issuing therefrom a "Joint Patent"). If either Party prosecutes a patent
application covering a Joint Invention, such Party shall [*], except as provided
in the final sentence of this paragraph. Except to the extent either Party is
restricted by the licenses granted to the other Party, and covenants contained,
herein, and to the extent permitted by law, each Party shall be entitled to [*].
Either Party may disclaim its interest in any particular Patent or patent
application covering a Joint Invention, in which case (i) the disclaiming Party
shall assign its ownership interest in such Patent or patent application to the
other Party for no additional consideration, (ii) the Party which is then the
sole owner shall be solely responsible for all future costs of such patent or
patent application, and (iii) the disclaiming Party shall hold no further rights
thereunder.

    9.3 Patent Term Extensions. Cubist will, [*], after discussing its strategy
with Gilead and [*], in each country in the Gilead Territory, determine for
which, if any, of the Patents within the Cubist Patents, Gilead Project Patents
and Joint Patents, the Parties will apply to extend the patent term with respect
to Licensed Products, as provided for in patent term extension laws or
regulations in the Gilead Territory similar to the Patent Term Restoration Act
or other similar laws and regulations affording an extension or restoration of
patent terms in the United States, which similar laws and regulations shall
include without limitation any Supplementary Protection Certificates. Cubist
shall act with reasonable promptness in light of the development stage of
Licensed Products to apply for any such extension. Gilead shall not make any
submissions, filings or other communications with any governmental agency with
respect to patent term restoration (or other similar grant of a monopoly right
with respect to any Licensed Product) for any Patents within the Cubist Patents,
Gilead Project Patents or Joint Patents in the Gilead Territory without Cubist's
express consent. Gilead will cooperate fully with Cubist in making such filings
[*] which may include without limitation, making available regulatory data and
information.

    9.4 Non-Patent Regulatory Exclusivity. Gilead shall have the right to apply
for regulatory exclusivity for the Licensed Products as provided in Section 4.7.

    9.5 Infringement of Patents by Third Parties.

    (a) Notification. Each Party shall promptly notify the other Party in
writing of any alleged or threatened infringement of the Cubist Patents and
Gilead Project Patents of which it becomes aware (such infringement,
"Infringement", and "Infringe" shall be interpreted accordingly).

    (b) Infringement of Cubist Patents in the Gilead Territory [*]. If the
Infringement of Cubist Patents involves or would involve a [*] in the Gilead
Territory only and not Licensed Products outside of the Gilead Territory, Gilead
shall have the right, but not the obligation, to bring, [ *], an

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appropriate action against the person or entity engaged in such Infringement
directly or contributorily. If Gilead does not bring such action within [*] of
notification thereof to or by Cubist pursuant to Section 9.5(a) or within [ *]
of the date upon which notification thereof to Cubist should have been given by
Gilead pursuant to Section 9.5(a) hereof, Cubist shall have the right, but not
the obligation, to bring [* ], such appropriate action. The Party not bringing
an action under this paragraph (b) shall be entitled to separate representation
in such matter by counsel of its own choice and at its own expense, but such
Party shall cooperate fully with the party bringing such action.

    (c) Other Infringement of Cubist Patents. For all Infringement of Cubist
Patents that involves or would involve a product that is [*] other than
Infringement described in Section 9.5(b), Cubist shall have the [* ] right, but
not the obligation, to bring, [* ], an appropriate action against any person or
entity engaged in such Infringement directly or contributorily. If Cubist does
not bring such action within [*] of notification thereof to or by Gilead
pursuant to Section 9.5(a) or within [*] of the date upon which notification
thereof to Gilead should have been given by Cubist pursuant to Section 9.5(a)
hereof, Gilead shall have the right, but not the obligation, to bring [* ], such
appropriate action; provided, however, that such appropriate action is brought
[*] and is limited only to [*] and not to[*] or otherwise to [* ]. The Party not
bringing an action under this paragraph (c) shall be entitled to separate
representation in such matter by counsel of its own choice and at its own
expense, but such Party shall cooperate fully with the Party bringing such
action.

    (d) Joint Patents. With respect to Third Party Infringement of Joint Patents
other than that Infringement described in Sections 9.5(b) and 9.5(c), the
Parties shall confer and take such action, and allocate expenses and recoveries,
in such manner as they shall agree.

    (e) Infringement of Gilead Project Patents Outside the Territory by [*]
Infringement. In the event the Infringement of a Gilead Project Patent involves
or would involve a [*] outside of the Gilead Territory, Cubist shall have the
right, but not the obligation, to bring, [*], an appropriate action against the
person or entity Infringing a Gilead Project Patent (including any Joint Patent)
directly or contributorily. If Gilead does not bring such action within [*] in
the case of an action brought under the Hatch-Waxman Act) of notification
thereof to or by Gilead, Cubist shall have the right, but not the obligation, to
bring [*], such appropriate action. The Party not bringing an action under this
Section 9.5(e) shall be entitled to separate representation in such matter by
counsel of its own choice and at its own expense, but such Party shall cooperate
fully with the party bringing such action.

    (f)  Other Infringement of Gilead Project Patents. For all Infringement
other than that described in Section 9.5(e) that involves a Gilead Project
Patent that is not a Joint Patent, Gilead shall have the exclusive right, but
not the obligation, to bring, [* ], an appropriate action against any person or
entity Infringing a Gilead Project Patent directly or contributorily.

    (g) Settlement; Allocation of Proceeds. Cubist shall not settle a claim
brought under this Section 9.5 involving Gilead Project Patents or Joint
Patents, or a claim brought under this Section 9.5 involving Cubist Patents that
would [*], in either case without the prior written consent of Gilead (which
consent shall not be unreasonably withheld or delayed). Gilead shall not settle
a claim brought under this Section 9.5 involving Cubist Patents or Joint
Patents, or a claim brought under this Section 9.5 involving Gilead Project
Patents that would [*], in either case without the prior written consent of
Cubist (which consent shall not be unreasonably withheld or delayed). In the
event of any recovery of monetary damages from the Third Party in an action
brought under this Section 9.5, [*], such recovery shall be allocated  [*], and
any remaining amounts shall be split as follows: (i) the portion of any such
remaining amounts that represents recovery for Infringement that involves or
would involve a product that [*] to Gilead and [*] to Cubist unless

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such remaining amounts are recovered in an action brought by Cubist pursuant to
Section 9.5(b) hereof in which case the portion of any such remaining amounts
that represents recovery for Infringement that involves or would involve a
product that [*], (ii) the portion of any such remaining amounts that represents
recovery for Infringement that involves or would involve a product that [*] for
Cubist and (iii) the portion of any such remaining amounts that represents
recovery for Infringement in an action brought pursuant to Section 9.5(d) shall
be split [*] to Gilead and [*] to Cubist unless Gilead and Cubist shall have
agreed to a different allocation.

    9.6 Infringement of Third Party Rights.

    (a) Notice. If any Licensed Product manufactured, used or sold by either
Party, its Affiliates, licensees or sublicensees under this Agreement becomes
the subject of a Third Party claim, or there is the potential for a claim, of
patent infringement relating to the manufacture, use, sale, offer for sale or
importation of Licensed Product, the Party first having notice of the claim
shall promptly notify the other Party, and the Parties shall promptly meet to
consider the claim and the appropriate course of action.

    (b) Defense. Except as provided herein, the Party against which such Third
Party infringement claim is brought shall defend against such claim at its sole
expense and the other Party shall have the right, but not the obligation, to
participate in any such suit, at its sole option and at its own expense. Such
other Party shall reasonably cooperate with the Party conducting the defense of
the claim, including if required to conduct such defense, furnishing a power of
attorney. Notwithstanding the foregoing provisions of this Section 9.6(b), [*].

    (c) Settlement. Neither Party shall enter into any settlement that affects
the other Party's rights or interests without such other Party's written
consent, which consent shall not be unreasonably withheld or delayed.

    (d) Indemnification.

    (i)  Subject to the provisions of this Section 9.6(d), Cubist shall
Indemnify (as defined in Section 11.1) Gilead and the Gilead Indemnitees (as
defined in Section 11.1) from and against any and all Losses arising from the
[*] of any Third Party intellectual property right (all such Losses,
"Section 9.6(d) Losses") by the manufacture, use, sale, offer for sale or
importation of Licensed Products by Gilead and its Affiliates, Permitted
Sublicensees and distributors; provided that Cubist shall not be obligated to
Indemnify Gilead or the Gilead Indemnitees pursuant to this Section 9.6(d)(i) to
the extent that (i) the alleged infringement arises out of Gilead's breach or
non-compliance with any of the provisions of this Agreement (including without
limitation the Supply Agreement), or (ii) such Section 9.6(d) Losses are Gilead
Indemnifiable Technology Losses. If Cubist is unable to procure any license from
a Third Party owning or controlling rights that would be infringed or
misappropriated by the development, manufacture, use or sale of Licensed
Products in the Gilead Territory on commercially reasonable terms, Cubist shall
so notify Gilead and Gilead shall discontinue manufacturing, using and selling
such Licensed Product; provided that prior to being required to cease such
activities, (i) the Parties shall first confer in good faith as promptly as
practicable as to whether to alter their approach to the infringing activities
with respect to the Licensed Product that would avoid such infringement without
adversely affecting their rights under this Agreement or return from the
Commercialization of Licensed Product in the Gilead Territory, (ii) the Third
Party owning such technology shall have refused to grant a license to Cubist on
commercially reasonable terms, and (iii) Cubist shall have afforded Gilead an
opportunity to seek such Third Party license and, within sixty (60) days of
being given such opportunity, such Third Party [*]. Notwithstanding the
foregoing, Cubist shall not be required to obtain any such license and Cubist
shall not be obligated to [*] that would cause [*]. Gilead may in its sole
discretion agree to [*] in order to allow Cubist to achieve [*].

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    (ii) If Cubist desires to incorporate or utilize any Gilead Project Know-How
or invention claimed by any Gilead Project Patent in or in connection with the
[*]. If Gilead agrees in writing, after such discussions by the Development
Subcommittee, that any such Gilead Project Technology shall be so incorporated
or utilized and shall be deemed "Gilead Indemnifiable Technology" hereunder,
then Gilead shall indemnify Cubist pursuant to the last sentence of this
Section 9.6(d)(ii). If Gilead does not so agree in writing, Cubist shall be
entitled to make such incorporation or utilization in connection with the
practice of the licenses set forth in Sections 6.2 and 6.4, but such Gilead
Project Technology shall not be Gilead Indemnifiable Technology and Gilead shall
not be obliged to indemnify Cubist as provided in such sentence. Gilead
Indemnifiable Technology shall also include any technology owned or Controlled
by Gilead (other than Cubist Technology or Joint Patents) that Gilead uses (but
that is not being used by Cubist, its Affiliates or sublicensees in connection
with Licensed Products outside the Gilead Territory) in the development,
manufacture, use, sale offer for sale or import of Licensed Products in the
Gilead Territory. Subject to the last sentence of this Section 9.6(d), Gilead
shall Indemnify Cubist and the Cubist Indemnitees (as defined in Section 11.1)
from and against any and all Losses to the extent arising from the infringement
or misappropriation of any Third Party intellectual property right (all such
Losses, "Gilead Indemnifiable Technology Losses") by the practice of Gilead
Indemnifiable Technology in the manufacture, use, sale, offer for sale or
importation of Licensed Products by or for Gilead and its Affiliates, Permitted
Sublicensees and distributors as otherwise permitted hereunder; provided that
Gilead shall not be obligated to Indemnify Cubist pursuant to this
Section 9.6(d)(ii) to the extent that (i) the alleged infringement or
misappropriation arises out of Cubist's breach or non-compliance with any of the
provisions of this Agreement, including without limitation the Supply Agreement,
or (ii) such Losses arise from the infringement or misappropriation of Third
Party intellectual property by the practice of Cubist Technology.

    (iii) If Gilead is obligated to indemnify Cubist pursuant to
Section 9.6(d)(ii) with respect to the practice of Gilead Indemnifiable
Technology outside of the Gilead Territory, and in connection with such
obligation is unable to procure any license from a Third Party owning or
Controlling rights that would be infringed or misappropriated by the
development, manufacture, use or sale of Licensed Products outside of the Gilead
Territory with respect to the Gilead Indemnifiable Technology on commercially
reasonable terms, Gilead shall so notify Cubist and [*], (i) the Parties shall
[*], (ii) the Third Party owning such technology shall have [*], and
(iii) Gilead shall have afforded Cubist an [*]. The provisions of this
Section 9.6(d) and Sections 9.7 and 11.6 state [*] in respect of liability for
infringement or misappropriation of any Third Party's intellectual property
right by the manufacture, use, sale, offer for sale or importation of any
Licensed Product.

    9.7 Royalty Reduction. If Gilead is required (either by final judgment from
a court of competent jurisdiction or pursuant to the terms of any settlement
that complies with the provisions of Section 9.6(c) above) to pay a Third Party
a royalty or make any payment of any kind for the right to practice the Cubist
Technology in a particular country in the Gilead Territory and Cubist is
required, [*], an amount [*] in respect of the [*]; provided, however, that
nothing in this Section 9.7 shall relieve Cubist or Gilead from its obligations
under Section 9.6 hereof.

    9.8 Patent Marking. Licensed Products marketed and sold by Gilead hereunder
shall be marked with appropriate patent numbers or indicia at Cubist's request
to the extent permitted by law, in those countries in which such markings have
notice value as against infringers of patents.

    9.9 Selection and Registration of Product Trademarks. Gilead may select and
own its own trademarks for use in connection with the sale of Licensed Products
within the Gilead Territory, in addition to the Cubist-owned trademarks to which
Gilead has a license pursuant to Section 6.7. Each Party shall be responsible
for registering and maintaining its own trademarks, at its own expense.

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    9.10 Infringement of Trademarks by Third Parties. With respect to Licensed
Products within the Gilead Territory, each Party shall notify the Steering
Committee promptly upon learning of any actual, alleged or threatened
infringement of any trademark or of any unfair trade practices, trade dress
imitation, passing off of counterfeit goods, or like offenses, or any such
claims brought by a Third Party against a Licensed Product (hereinafter "TM
Infringement"). Upon learning of such TM Infringement, the Steering Committee
[*]. In the absence of other agreement [*], to bring an action to address such
TM Infringement, in which case such Party [*].

    9.11 Patent Oppositions.

    (a) Third Party Patent Rights. If either Party desires to bring an
opposition, action for declaratory judgment, nullity action, interference,
reexamination or other attack upon the validity, title or enforceability of a
Patent owned or Controlled by a Third Party that covers the manufacture, use or
sale of any Licensed Product, such Party shall so notify the other Party and the
Parties shall promptly confer to determine whether to bring such action or the
manner in which to settle such action. Cubist shall have the first right, but
not the obligation, to bring at its own expense and in its sole control such
action outside the Gilead Territory. Gilead shall have the first right, but not
the obligation, to bring at its own expense and in its sole control such action
in the Gilead Territory. If Gilead does not bring such action within [*] of
notification thereof pursuant to this Section 9.11(a) (or earlier, if required
by the nature of the proceeding), Cubist shall have the right, but not the
obligation, to bring at Cubist's expense and in its sole control, such action.
The Party not bringing an action under this Section 9.11(a) shall be entitled to
separate representation in such proceeding by counsel of its own choice and at
its own expense, and shall cooperate fully with the Party bringing such action.
Any awards or amounts received in bringing any such action shall be first
allocated to [*].

    (b) Parties' Patent Rights. If a Cubist Patent or a Gilead Project Patent
becomes the subject of any proceeding commenced by a Third Party in connection
with an opposition, reexamination request, action for declaratory judgment,
nullity action, interference or other attack upon the validity, title or
enforceability thereof, then the Party owning or Controlling such Patent shall
control such defense at its sole cost; provided that if such action relates to a
Joint Patent, the Parties shall confer and determine which Party shall control
such action. The controlling Party will permit the non-controlling Party to
participate in the proceeding to the extent permissible under law, and to be
represented by its own counsel in such proceeding, at the non-controlling
Party's expense. If either Party decides that it does not wish to defend against
such action, then the other Party shall have a backup right to assume defense of
such Third Party action at its own expense. Any awards or amounts received in
defending any such Third Party action shall be allocated [*].

    (c) Noncontravention. Nothing in this Section 9.11 shall be deemed to
relieve either Party of its obligations under Section 9.6(d) or Article 11.

    9.12 Lilly License. Notwithstanding the foregoing, the Parties' rights and
obligations under this Article 9 shall be subject to limitations imposed by the
Lilly License, provided that the Parties shall work to address such limitations
in a manner that permits Gilead to exercise its rights under this Agreement to
the fullest extent reasonably possible.

ARTICLE 10
REPRESENTATIONS AND WARRANTIES

    10.1 Mutual Representations and Warranties. Each Party hereby represents and
warrants to the other Party as follows:

    (a) Corporate Existence and Power. It is a corporation duly organized,
validly existing and in good standing under the laws of the state in which it is
incorporated, and has full corporate power

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and authority and the legal right to own and operate its property and assets and
to carry on its business as it is now being conducted and as contemplated in
this Agreement, including, without limitation, the right to grant the licenses
granted hereunder.

    (b) Authority and Binding Agreement. As of the Effective Date, (a) it has
the corporate power and authority and the legal right to enter into this
Agreement and perform its obligations hereunder; (b) it has taken all necessary
corporate action on its part required to authorize the execution and delivery of
the Agreement and the performance of its obligations hereunder; and (c) the
Agreement has been duly executed and delivered on behalf of such Party, and
constitutes a legal, valid and binding obligation of such Party that is
enforceable against it in accordance with its terms.

    (c) No Conflict. It has not entered, and will not enter, into any agreement
with any Third Party that is in conflict with the rights granted to the other
Party under this Agreement, and has not taken and will not take any action that
would in any way prevent it from granting the rights granted to the other Party
under this Agreement, or that would otherwise materially conflict with or
adversely affect the rights granted to the other Party under this Agreement. Its
performance and execution of this Agreement will not result in a breach of any
other contract to which it is a Party.

    (d) Regulatory Data. The regulatory data it provides to the other Party
shall be complete and accurate in all material respects.

    (e) No Misappropriation. It has not and shall not misappropriate the trade
secret of another in its activities to develop or commercialize Licensed
Products.

    (f)  No Debarment. Each Party represents and warrants that in the course of
the development of Licensed Products, such Party shall not have used, during the
term of this Agreement, any employee or consultant that has been debarred by the
FDA or Regulatory Authorities, or, to the best of such Party's knowledge, is the
subject of debarment proceedings by the FDA or Regulatory Authorities.

    10.2 Cubist. Cubist represents and warrants to Gilead as follows:

    (a) Non-Infringement of Cubist Technology by Third Parties. As of the
Effective Date, Cubist is unaware of any activities by Third Parties which would
constitute infringement or misappropriation of the Cubist Technology.

    (b) Lilly License. Cubist is in full compliance with the Lilly License as of
the Effective Date, and has received no notices of default under the Lilly
License.

    (c) Regulatory Data. Cubist is not aware of any data or information given to
Gilead relating to Licensed Products that is untrue or inaccurate in any
material respect or of any other data or information that is necessary to make
the data and information provided to Gilead complete and not misleading in all
material respects.

    (d) Oral Product Rights. Cubist owes no obligation [*] which would conflict
with the rights granted Gilead herein, including without limitation the
exclusive license with respect to all Licensed Products (including without
limitation Oral Products) that Gilead continues pursuant to this agreement to
enjoy even after a [*] described by clause (II) or (III) of Section 8.1(c).

    (e) Rights in Technology. As of the Effective Date, Cubist has sufficient
right in and to the Cubist Technology, free and clear of any liens or
encumbrances, to grant the rights set forth in this Agreement.

    (f)  Non-infringement of Third Party Rights. As of the Effective Date,
Cubist is unaware of any Patents or trade secret rights owned or controlled by a
Third Party, which would be infringed

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or misappropriated by the manufacture, use, sale, offer for sale or importation
of Daptomycin Products, and has received no, and has reason to believe that it
would receive any, written claims relating to any claims of such infringement or
misappropriation.

    10.3 Disclaimer. Gilead understands that Licensed Products are the subjects
of ongoing clinical research and development and that Cubist cannot assure the
safety or usefulness of Licensed Products. Cubist makes no warranty except as
set forth in this Article 10 concerning its Patents or Know-How.

    10.4 No Other Representations. THE EXPRESS REPRESENTATIONS AND WARRANTIES
STATED IN THIS ARTICLE 10 ARE IN LIEU OF ALL OTHER REPRESENTATIONS AND
WARRANTIES, EXPRESS, IMPLIED, OR STATUTORY, INCLUDING WITHOUT LIMITATION,
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
NON-INFRINGEMENT OR NON-MISAPPROPRIATION OF THIRD PARTY INTELLECTUAL PROPERTY
RIGHTS.

ARTICLE 11
INDEMNIFICATION

    11.1 Indemnification by Cubist. Cubist hereby agrees to defend, hold
harmless and indemnify (collectively "Indemnify") Gilead and its Affiliates,
agents, directors, officers and employees (the "Gilead Indemnitees") from and
against any and all suits, claims, actions, demands, liabilities, expenses
and/or losses, including without limitation reasonable legal expenses and
attorneys' fees (collectively "Losses") resulting directly or indirectly from
(i) a breach of any of Cubist's representations and warranties pursuant to
Article 10; (ii) any claims resulting directly or indirectly from the secondment
of a Cubist MSL in the Gilead Territory other than to the extent arising
directly from an action taken by a Cubist MSL in accordance with Gilead's
specific instructions; or (iii) the development, use, sale, offer for sale or
importation of Licensed Products by Cubist or its Affiliates, licensees or
sublicensees; provided, however, that Cubist shall not be required pursuant to
this Section 11.1 to indemnify the Gilead Indemnitees for any Section 9.6(d)
Losses. Cubist's obligation to Indemnify the Gilead Indemnitees pursuant to this
Section 11.1 shall not apply to the extent of any Losses (i) that arise from the
negligence or intentional misconduct of any Gilead Indemnitee; (ii) from
Gilead's breach of this Agreement, including without limitation the Supply
Agreement; or (iii) for which Gilead is obligated to Indemnify the Cubist
Indemnitees pursuant to Section 11.2 or the Supply Agreement. Cubist's
obligations to indemnify Gilead with respect to the manufacture and supply of
Licensed Product are set forth in the Supply Agreement.

    11.2 Indemnification by Gilead. Gilead hereby agrees to Indemnify Cubist and
its Affiliates, agents, directors, officers and employees (the "Cubist
Indemnitees") from and against any and all Losses resulting directly or
indirectly from (i) a breach of any of Gilead's representations and warranties
pursuant to Article 10; or (ii) the development, use, sale, offer for sale or
importation of Licensed Products by Gilead or its Affiliates or sublicensees.
Gilead's obligation to Indemnify the Cubist Indemnitees pursuant to the
foregoing sentence shall not apply to the extent of any Losses (i) that arise
from the negligence or intentional misconduct of any Cubist Indemnitee, (ii) for
which Cubist is obligated to Indemnify the Gilead Indemnitees pursuant to
Section 11.1, or (iii) from any breach by Cubist of this Agreement, including
without limitation the Supply Agreement. Gilead's obligations to indemnify
Cubist with respect to the manufacture and supply of Licensed Products are set
forth in the Supply Agreement.

    11.3 Procedure. If either Party is seeking indemnification under
Section 11.1 or 11.2 in connection with a Third Party claim, it shall inform the
indemnifying Party of such Third Party claim giving rise to the obligation to
indemnify pursuant to such section as soon as reasonably practicable after
receiving notice of the claim. The indemnifying Party shall have the right to
assume the defense of any such Third Party claim for which it is obligated to
indemnify the indemnified Party under Section 11.1 or

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11.2. The indemnified Party shall cooperate with the indemnifying Party (and its
insurer) as the indemnifying Party may reasonably request, and at the
indemnifying Party's sole cost and expense. The indemnified Party shall have the
right to participate, at its own expense and with counsel of its choice, in the
defense of any claim or suit that has been assumed by the indemnifying Party.
Neither Party shall have any obligation to indemnify the other Party in
connection with any settlement made without the indemnifying Party's written
consent, provided that the indemnifying Party does not unreasonably withhold or
delay any such written consent. If the Parties cannot agree as to the
application of Sections 11.1 or 11.2 to any Third Party claim, the Parties may
conduct separate defenses of such claims, with each Party retaining the right to
claim indemnification from the other in accordance with Section 11.1 or 11.2
upon resolution of the underlying claim.

    11.4 Insurance. Each Party shall procure and maintain insurance or
self-insurance, including product liability insurance, adequate to cover its
obligations hereunder and which are consistent with normal business practices of
prudent companies similarly situated at all times during which any Licensed
Product is being clinically tested with human subjects or commercially
distributed or sold by Gilead. It is understood that such insurance shall not be
construed to create a limit of either Party's liability with respect to its
indemnification obligations under this Article 11. Each Party shall provide the
other with written evidence of such insurance (or financial information that
describes the amounts available under any self-insurance facility) upon request.
Each Party shall provide the other with written notice at least [*] prior to the
cancellation, non-renewal or material change in such insurance or self-insurance
which materially adversely affects the rights of the other Party hereunder.

    11.5 No Application to Third Party Infringement Claims. Except for the
provisions of Section 11.4 above and Section 11.6 below, the provisions of this
Article 11 shall not apply to any claims by a Third Party for infringement of
such Third Party's patents or other intellectual property or to any Losses
suffered or incurred by either Party arising from, or related to, any such
claims by a Third Party. The indemnification rights and obligations of both
Parties with respect to any such claims by a Third Party are provided for in
Section 9.6(d) hereof.

    11.6 Limitation of Liability. EXCEPT AS EXPRESSLY PROVIDED IN THIS
AGREEMENT, INCLUDING WITHOUT LIMITATION IN THIS ARTICLE 11, AND EXCEPT FOR
INFRINGEMENT BY EITHER PARTY OF THE OTHER PARTY'S INTELLECTUAL PROPERTY RIGHTS
OR BREACH OF CONFIDENTIALITY OBLIGATIONS UNDER ARTICLE 13, NEITHER PARTY SHALL
BE LIABLE TO THE OTHER FOR LOST PROFITS OR FOR ANY INDIRECT, INCIDENTAL,
CONSEQUENTIAL, SPECIAL, PUNITIVE OR EXEMPLARY DAMAGES OF THE OTHER PARTY IN
CONNECTION WITH THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED BY THIS
AGREEMENT, HOWEVER CAUSED, UNDER ANY THEORY OF LIABILITY (COLLECTIVELY, "OTHER
DAMAGES"). IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR OTHER DAMAGES IN EXCESS
OF [*] (THE "SECTION 11.6 CAP"). IT IS EXPRESSLY UNDERSTOOD THAT THE OBLIGATION
OF EITHER PARTY UNDER ARTICLE 11 TO INDEMNIFY FOR AMOUNTS THAT THE OTHER PARTY
ACTUALLY PAYS TO A THIRD PARTY SHALL NOT BE LIMITED BY THE SECTION 11.6 CAP.

ARTICLE 12
RECORDS; PUBLICATIONS

    12.1 Records. Each Party shall keep or cause to be kept such records as are
required to determine, in a manner consistent with generally accepted accounting
principles in the United States, the sums or credits due under this Agreement,
including, but not limited to Incremental Product Development Expenses, Transfer
Prices and Net Sales. At the request (and expense) of either Party, the other
Party and its Affiliates and licensees and sublicensees shall permit an
independent certified public accountant appointed by such Party and reasonably
acceptable to the other Party, accompanied by representatives of the financial
department of the audited Party at reasonable times, upon reasonable notice and
no

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more frequently than once per calendar year, to examine only those records as
may be necessary to determine, with respect to any calendar year ending not more
than [*] prior to such Party's request, the correctness or completeness of any
report or payment made under this Agreement. Results of any such examination
shall be (i) limited to information relating to the Licensed Products, (ii) made
available to both Parties, and (iii) subject to Article 13. The Party requesting
the audit shall bear the full cost of the performance of any such audit, unless
such audit discloses a variance of more than [*] from the amount of the original
report, royalty or payment calculation. In such case, the Party being audited
shall bear the full cost of the performance of such audit.

    12.2 Publications. Neither Party shall publish or present the results of
studies carried out under this Agreement without the opportunity for prior
review by the other Party. Subject to Section 13.2, each Party agrees to provide
the other Party the opportunity to review any proposed abstracts, manuscripts or
presentations (including verbal presentations) which relate to any Licensed
Product at least [*] prior to their intended submission for publication and
agrees, upon request, not to submit any such abstract or manuscript for
publication, or to make such presentation, until the other Party is given a
reasonable period of time to secure patent protection for any material in such
publication or presentation which it believes to be patentable. Both Parties
understand that a reasonable commercial strategy may require delay of
publication or presentation of information or filing of patent applications. The
Parties agree to review and consider delay of publication or presentation and
filing of patent applications under certain circumstances. The Steering
Committee will review such requests and recommend subsequent action. Neither
Party shall have the right to publish or present Confidential Information of the
other Party, and each Party shall remove the Confidential Information of the
other Party from any proposed publication or presentation upon request by such
other Party. Nothing contained in this Section 12.2 shall prohibit the inclusion
of information necessary to file a patent application with a government
authority, except for Confidential Information of the non-filing Party, provided
the non-filing Party is given a reasonable opportunity to review the information
to be included prior to submission of such patent application. Notwithstanding
the foregoing, the Parties recognize that independent investigators have been
engaged, and will be engaged in the future, to conduct clinical trials of
Licensed Products. Independent investigators that have been engaged by a Party
or both Parties prior to or on the Effective Date may release information
regarding such studies in a manner consistent with academic standards within the
scope of such investigator's agreement with the relevant Party. Independent
investigators that are engaged by a Party or both Parties after the Effective
Date are understood to operate in an academic environment and shall be allowed
to release information regarding such studies in a manner consistent with
academic standards; provided, however, that the Party in privity with such
investigators shall discourage such disclosures if detrimental to the
collaboration.

ARTICLE 13
CONFIDENTIALITY

    13.1 Treatment of Confidential Information. The Parties agree that during
the Term, and for a period of [* ] after this Agreement expires or terminates, a
Party receiving Confidential Information of the other Party shall (i) maintain
in confidence such Confidential Information to the same extent such Party
maintains its own proprietary industrial information of similar kind and value
(but at a minimum each Party shall use commercially reasonable efforts to
maintain Confidential Information in confidence); (ii) not disclose such
Confidential Information to any Third Party without prior written consent of the
disclosing Party, except for disclosures made in confidence to any Third Party
pursuant to a plan approved by the Steering Committee or to its licensees or
sublicensees who agree to be bound by obligations of non-disclosure and non-use
at least as stringent as those contained in this Article 13; and (iii) not use
such Confidential Information for any purpose except those purposes permitted by
this Agreement.

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    13.2 Authorized Disclosure. Notwithstanding any other provision of this
Agreement, each Party may disclose Confidential Information of the other Party:

    (a) to the extent and to the persons and entities required by an applicable
governmental law, rule or regulation or court order; provided, however, that the
Party required to disclose Confidential Information shall first have given
prompt notice to the other Party hereto to enable it to seek any available
exemptions from or limitations on such disclosure requirement and shall
reasonably cooperate in such efforts by the other Party;

    (b) to the extent and to the persons and entities required by rules of the
National Association of Securities Dealers;

    (c) as necessary to file or prosecute patent applications, prosecute or
defend litigation or otherwise establish rights or enforce obligations under
this Agreement, but only to the extent that any such disclosure is necessary. In
particular, the Parties acknowledge that Cubist and/or Gilead may be obligated
to file a copy of this Agreement with the U.S. Securities and Exchange
Commission with its next quarterly report on Form 10-Q, annual report on
Form 10-K or current report on Form 8-K or with any registration statement filed
with the U.S. Securities and Exchange Commission (the "SEC") pursuant to the
Securities Act of 1933, as amended. In the event of any such filing, the Parties
agree to cooperate and work together to request confidential treatment pursuant
to, and in accordance with, the rules and regulations of the SEC; or

    (d) as required by the Lilly License.

    13.3 Publicity. The Parties agree that the joint public announcement of the
execution of this Agreement shall be substantially in the form of the press
release attached as Exhibit H. Any other publication, news release or other
public announcement relating to this Agreement or to the performance hereunder,
shall first be reviewed and approved by both Parties, which approval shall not
be unreasonably withheld.

ARTICLE 14
TERM AND TERMINATION

    14.1 Term. This Agreement shall become effective on the Effective Date and
shall remain in effect, unless earlier terminated pursuant to this Article 14
with respect to each Licensed Product until the expiration of the last royalty
obligation relating to sales of such Licensed Product as provided in Article 8.

    14.2 Termination by Gilead. Gilead shall have, [*], the right to terminate
this Agreement [*] upon [*] written notice to Cubist. If Gilead terminates this
Agreement [*] Licensed Product pursuant to this Section 14.2, (i) Gilead shall
provide Cubist with all reasonable assistance during the [*] notice period to
effect the transfer of all regulatory activities, regulatory filings and
Regulatory Approvals in the Gilead Territory for Licensed Product(s) as to which
such termination is effective to Cubist, (ii) Cubist shall promptly wind down
its efforts under any Proposed Modification to a protocol for a clinical trial
being conducted by Cubist for such Licensed Product(s) pursuant to Section 3.4
that the Steering Committee approves, to the extent reasonably practicable
without adversely affecting the value of the data to be obtained from such
clinical trial to Cubist or compromising patient safety, and (iii) Gilead shall
wind down its efforts to develop and commercialize such Licensed Product(s) in
the Gilead Territory. Gilead shall continue to [*] pursuant to its [*] as to
which this Agreement is terminated that is ongoing as of the date upon which
Gilead provides a termination notice for such Licensed Product(s) pursuant to
this Section 14.2, but Gilead shall not be responsible for [*] with respect to
the Licensed Product(s) that are the subject of such trial. The Steering
Committee shall oversee any such wind down efforts. Additionally, after
termination of this Agreement pursuant to this Section 14.2, [*] with respect to
which this Agreement is terminated prior to the effective date of such
termination, but not for [*].

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    14.3 Termination for Breach.

    (a) Notice. If either Party believes that the other is in material breach of
this Agreement with respect to one or more Licensed Products, then the Party
holding such belief (the "Non-breaching Party") may deliver notice of such
breach to the other Party (the "Notified Party"). Other than as explicitly
provided for in Sections 3.5 or 5.6, a breach by either Party of its Diligence
Obligation shall not be deemed to be a material breach of this Agreement. The
Notified Party shall have [*] to either cure such breach or, if cure cannot be
reasonably effected within such [*] period, to deliver to the Non-breaching
Party a plan to cure such breach within a timeframe that is reasonably prompt in
light of the circumstances then prevailing. Following delivery of such plan, the
notified Party shall use Commercially Reasonable Efforts to carry out the plan
and cure the breach.

    (b) Failure to Cure. If the Notified Party fails to cure such breach as
provided for in Section 14.3(a), the Non-breaching Party may terminate this
Agreement either in its entirety or with respect to one or more Licensed
Products upon written notice to the Notified Party; provided, however, that
alleged breaches by either Party of its Diligence Obligations pursuant to
Section 3.1 or 5.5 shall be handled initially as provided in Section 3.5 or 5.6.

    (c) Disputes. If a Party gives notice of termination under this Section 14.3
and the other Party disputes whether such termination is proper under this
Section 14.3, then the issue of whether this Agreement may properly be
terminated upon expiration of the notice period (unless such breach is cured as
provided in Section 14.3(a)) shall be resolved in accordance with Article 15. If
as a result of such dispute resolution process it is determined that the notice
of termination was proper, then such termination shall be deemed to have been
effective [* ] following the date of the notice of termination. If as a result
of such dispute resolution process it is determined that the notice of
termination was improper, then no termination shall have occurred and this
Agreement shall remain in effect.

    (d) Termination as to Certain Licensed Products. Notwithstanding the
foregoing provisions of this Section 14.3, either Party may exercise its right
to terminate the Agreement pursuant to this Section 14.3 with respect to one or
more particular Licensed Products as to which the other Party has breached its
obligations under this Agreement, rather than with respect to the entire
Agreement, in which case the notice provided by such Party pursuant to
Section 14.3(a) shall specify that the Agreement is being terminated pursuant to
this Section 14.3 only with respect to certain Licensed Products listed in such
notice. If either Party makes such an election under this Section 14.3(d), then
subsections (a) through (c) shall be deemed to refer to termination of the
Agreement only with respect to those Licensed Products set forth in the notice
provided pursuant to Section 14.3(a).

    14.4 Cubist Rights upon Certain Terminations of the Agreement or as to
Certain Licensed Products. If Cubist terminates this Agreement in its entirety
or with respect to one or more Licensed Product(s) pursuant to Section 14.3, or
Gilead terminates this Agreement in its entirety or with respect to any Licensed
Products pursuant to Section 14.2 (such Licensed Products as to which Gilead or
Cubist has terminated Gilead's rights, or all Licensed Products if the Agreement
is terminated in its entirety, "Reverted Products"), then:

    (a) Gilead hereby grants to Cubist a nonexclusive, royalty-free license,
with the right to grant sublicenses, to use the Gilead Marks in connection with
the commercialization of Reverted Products (collectively "Permitted Uses").
Promptly after any such termination of this Agreement in its entirety or
Gilead's rights with respect to certain Licensed Products, Gilead shall execute
any documents required in the reasonable opinion of Cubist for Cubist to be
entered as a "registered user" or recorded licensee of the Gilead Marks for
Permitted Uses, or for Gilead to be removed as registered user or licensee
thereof.

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    (b) Gilead shall transfer to Cubist all Drug Approval Applications and
Regulatory Approvals for Reverted Products that Gilead holds as of the time of
such termination. In such event, Gilead shall take all actions reasonably
necessary to effect such transfer of such Drug Approval Applications and
Regulatory Approvals for Reverted Products to Cubist.

    (c) The licenses granted by Cubist and by Gilead under Article 6 shall
terminate with respect to Reverted Products. Gilead shall grant to Cubist a
nonexclusive, worldwide, royalty-free, license, with the right to grant
sublicenses, under the Gilead Project Technology to develop, make, use, sell,
offer for sale and import Reverted Products.

    (d) Upon termination of this Agreement for any reason with respect to any or
all Licensed Products and, if applicable, after the sell-out period set forth in
Section 14.5 hereof has expired, Gilead shall discontinue making any
representation regarding its status as a licensee of or distributor for Cubist
in the Gilead Territory for all Reverted Products, and shall cease conducting
any activities with respect to the marketing, promotion, sale or distribution of
the Reverted Product in the Gilead Territory.

    14.5 Gilead Rights upon Certain Terminations. If Gilead terminates this
Agreement pursuant to Section 14.3 in its entirety or with respect to one or
more Licensed Product(s), then [*] with respect to [*] for which [* ], shall [*]
for so long as [*], except that [*] shall [*], without [*], and Gilead shall
have no further obligations under this Agreement with respect to any such
Licensed Product(s) other than [*], which shall last [*] as required by [*], and
any other [*] that [*]. In addition, each Party's [*] with respect to [*] shall
[*]. Gilead shall [*].

    14.6 Survival. The following provisions shall survive any expiration or
termination of this Agreement for the period of time specified: Articles 11
(other than Section 11.4, and, subject to Section 14.5, only with respect to
actions arising with respect to periods prior to termination), 12, 14, 15 and
16, and Sections 4.3 (but solely as necessary to effect the exchange of adverse
events information in conjunction with Section 4.5), 4.5, 6.7 (but solely as to
marks used in connection with Licensed Products during the Term), 7.2(e) (but
only for [* ] beyond the end of the Term), 8.6 (but only for [*] and in relation
to Net Sales made during the Term), 9.6(d) (subject to Section 14.5, with
respect to actions arising with respect to periods prior to termination), 13.1
and 13.2, and in the case of any of the foregoing and other Section that by
their terms explicitly survive beyond the Term, each such Section shall survive
beyond the Term only for the length of time specified in such Section. The
foregoing provisions that survive in the event of any expiration or termination
of this Agreement shall survive in addition to those that survive any
termination under Section 14.4 or 14.5, as specifically provided in such
sections. Termination of this Agreement shall not relieve the Parties of any
liability which accrued hereunder prior to the effective date of such
termination nor preclude either Party from pursuing all rights and remedies it
may have hereunder or at law or in equity with respect to any breach of this
Agreement nor prejudice either Party's right to obtain performance of any
obligation. The remedies provided in this Article 14 are not exclusive of any
other remedies a Party may have in law or equity.

    14.7 Clarification with respect to Supply Agreement. Upon The Parties'
execution of the Supply Agreement, references to the Agreement in Sections 14.2,
14.3, 14.4, 14.5 and 14.6 shall be interpreted to apply to this Agreement and to
the Supply Agreement as if they were one agreement.

    14.8 Repurchase of Inventory. Upon any termination of this Agreement by
Gilead, Cubist shall have the obligation, upon request of Gilead, to repurchase
all of the inventory of the Licensed Product held by Gilead or its sublicensees
in the Gilead Territory, provided such inventory is in resalable condition. The
price for such inventory shall be [*]. Gilead shall notify Cubist within [*]
days after termination if Gilead wishes to have Cubist repurchase inventory and
Cubist shall issue a return authorization to Gilead and Gilead shall ship the
Licensed Product to Cubist [*]. If Gilead does not

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exercise its right to have Cubist repurchase inventory pursuant to this
Section 14.8, Gilead shall have the right to sell out its inventory for a period
of [*] from the date of termination.

ARTICLE 15
DISPUTE RESOLUTION

    15.1 Disputes. The Parties recognize that disputes as to certain matters may
from time to time arise during the term of this Agreement which relate to either
Party's rights and/or obligations hereunder. It is the objective of the Parties
to establish procedures to facilitate the resolution of disputes arising under
this Agreement in an expedient manner by mutual cooperation and without resort
to litigation. To accomplish this objective, the Parties agree to follow the
procedures set forth in this Section 15.1 if and when a dispute arises under
this Agreement. All disputes arising under this Agreement shall be discussed
first by the Steering Committee. If the Steering Committee is unable to resolve
any dispute within [* ] after such dispute is submitted to it, either Party may,
by written notice to the other Party, have such dispute referred to their
respective executive officers designated below or their successors for attempted
resolution by good faith negotiations within [*] after such notice is received.
Such designated officers are as follows:

    For Gilead:    Chief Executive Officer

    For Cubist:    Chief Executive Officer

    If the designated officers are not able to resolve such dispute within such
[*] period, either Party may at any time thereafter pursue any legal or
equitable remedy available to it.

    15.2 Governing Law; Judicial Resolution. Resolution of all disputes arising
out of or related to this Agreement or the performance, enforcement, breach or
termination of this Agreement and any remedies relating thereto, shall be
governed by and construed under the substantive laws of the State of New York,
as applied to Agreements executed and performed entirely in the State of New
York by residents of the State of New York, without regard to conflicts of law
rules. Any dispute arising under this Agreement shall be submitted to a state or
federal court of competent jurisdiction, except as otherwise expressly provided
in this Agreement.

    15.3 Patent and Trademark Dispute Resolution. Any dispute, controversy or
claim relating to the scope, validity, enforceability or infringement of any
patent rights covering the manufacture, use or sale of any Licensed Product or
of any trademark rights relating to any Licensed Product shall be submitted to a
court of competent jurisdiction in the territory in which such patent or
trademark rights were granted or arose.

    15.4 [*] Resolution of Certain Disputes. Issues relating to whether either
Party is meeting its Diligence Obligations designated for resolution by a [*]
pursuant to Section 3.5 or 5.6, modification of Section 1.29 with respect to
Directly Competitive Product of an Oral Product, and whether Gilead has properly
determined the amount of Promotional Resources under Section 5.7, shall be
finally determined as set forth in this Section 15.4. Within [ *] after a Party
proposes to submit an issue for resolution by a [*], each Party shall [*].
Neither of such [*] may be [*], and neither of such [*]. Within [*] days after
expiration of such [*] period, the [*] shall [*] the issue(s) presented by the
Parties. [*]. Each Party shall submit written materials to the other Party and
to [*] relating to the matters in issue within [*] after [*]. Each Party shall
then have [*] to submit a written rebuttal to the other Party's materials to the
other Party [*]. The [*] shall decide the issue presented to them pursuant to
Section 5.6, within [*] after they receive all such written materials from each
Party. The [*] shall have the discretion to [*]. Each Party shall cooperate with
[*]. The [*] determination shall be dispositive of all issues presented to it
and such determination shall be given retroactive effect. Until such
determination is delivered to the Parties, the Parties shall continue to perform
their obligations under

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this Agreement in good faith and make any applicable payments accordingly. The
Parties shall bear all expenses incurred pursuant to this Section 15.4 equally.

ARTICLE 16
MISCELLANEOUS

    16.1 Entire Agreement; Amendment. This Agreement, including the Exhibits
hereto, sets forth the complete, final and exclusive agreement and all the
covenants, promises, agreements, warranties, representations, conditions and
understandings between the Parties hereto and supersedes and terminates all
prior agreements and understandings between the Parties. There are no covenants,
promises, agreements, warranties, representations, conditions or understandings,
either oral or written, between the Parties other than as are set forth herein
and therein. No subsequent alteration, amendment, change or addition to this
Agreement shall be binding upon the Parties unless reduced to writing and signed
by an authorized officer of each Party.

    16.2 Force Majeure. Both Parties shall be excused from the performance of
their obligations under this Agreement to the extent that such performance is
prevented by force majeure and the nonperforming Party promptly provides notice
of the prevention to the other Party. Such excuse shall be continued so long as
the condition constituting force majeure continues and the nonperforming Party
uses reasonable efforts to remove the condition. For purposes of this Agreement,
force majeure shall include conditions beyond the control of the Parties,
including without limitation, an act of God, voluntary or involuntary compliance
with any regulation, law or order of any government, war, civil commotion, labor
strike or lock-out, epidemic, failure or default of public utilities or common
carriers, destruction of production facilities or materials by fire, earthquake,
storm or like catastrophe; provided, however, the payment of invoices due and
owing hereunder shall not be delayed by the payor because of a force majeure
affecting the payor.

    16.3 Notices. Any notice required or permitted to be given under this
Agreement shall be in writing, shall specifically refer to this Agreement and
shall be deemed to have been sufficiently given for all purposes if mailed by
first class certified or registered mail, postage prepaid, express delivery

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service or personally delivered, or if sent by facsimile, electronic
transmission confirmed. Unless otherwise specified in writing, the mailing
addresses of the Parties shall be as described below.

For Gilead:   Gilead Sciences, Inc.
333 Lakeside Drive,
Foster City, CA 94404
Attn: Vice-President of Corporate Development
Fax: (650) 522-5488
cc: General Counsel
Fax: (650) 522-5537
With a Copy to:
 
Cooley Godward LLP
Five Palo Alto Square
3000 El Camino Real
Palo Alto, CA 94306
Fax: (650) 849-7400
Attention: Robert L. Jones, Esq.
For Cubist:
 
Cubist Pharmaceuticals, Inc.
24 Emily Street
Cambridge, Massachusetts 02139
Attention: Head of Corporate Development and Licensing
Fax: (617) 234-5592
With a Copy to:
 
Bingham Dana LLP
150 Federal Street
Boston, Massachusetts 02492
Attention: Julio E. Vega, Esq.
Fax: (617) 951-8736

    16.4 Maintenance of Records. Each Party shall keep and maintain all records
required by law or regulation with respect to Licensed Products and shall make
copies of such records available to the other Party upon request.

    16.5 No Strict Construction. This Agreement has been prepared jointly and
shall not be strictly construed against either Party.

    16.6 Assignment. Neither Party may assign or transfer this Agreement or any
rights or obligations hereunder without the prior written consent of the other,
except that a Party may make such an assignment without the other Party's
consent to Affiliates or to a successor to substantially all of the business of
such Party, whether in a merger, sale of stock, sale of assets or other
transaction, and except to the extent provided in Section 10.06 of the Lilly
License. Any permitted successor or assignee of rights and/or obligations
hereunder shall, in a writing to the other Party, expressly assume performance
of such rights and/or obligations. The Cubist Technology and the Gilead Project
Technology shall exclude any intellectual property held or developed by a
permitted successor of the relevant Party not in connection with Daptomycin
Products. Any permitted assignment shall be binding on the successors of the
assigning Party. Any assignment or attempted assignment by either Party in
violation of the terms of this Section 16.6 shall be null and void and of no
legal effect.

    16.7 Performance by Affiliates. Each of Cubist and Gilead acknowledge that
obligations under this Agreement may be performed by Affiliates of Cubist and
Gilead. Each of Cubist and Gilead guarantee performance of this Agreement by its
Affiliates. Wherever in this Agreement the Parties delegate responsibility to
Affiliates or local operating entities, the Parties agree that such entities may
not make

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decisions inconsistent with this Agreement, amend the terms of this Agreement or
act contrary to its terms in any way.

    16.8 Counterparts. This Agreement may be executed in two (2) or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

    16.9 Further Actions. Each Party agrees to execute, acknowledge and deliver
such further instruments, and to do all such other acts, as may be necessary or
appropriate in order to carry out the purposes and intent of this Agreement.

    16.10 Severability. If any one or more of the provisions of this Agreement
is held to be invalid or unenforceable by any court of competent jurisdiction
from which no appeal can be or is taken, the provision shall be considered
severed from this Agreement and shall not serve to invalidate any remaining
provisions hereof. The Parties shall make a good faith effort to replace any
invalid or unenforceable provision with a valid and enforceable one such that
the objectives contemplated by the Parties when entering this Agreement may be
realized.

    16.11 Headings. The headings for each article and section in this Agreement
have been inserted for convenience of reference only and are not intended to
limit or expand on the meaning of the language contained in the particular
article or section.

    16.12 No Waiver. Any delay in enforcing a Party's rights under this
Agreement or any waiver as to a particular default or other matter shall not
constitute a waiver of such Party's rights to the future enforcement of its
rights under this Agreement, except with respect to an express written and
signed waiver relating to a particular matter for a particular period of time.

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    IN WITNESS WHEREOF, the Parties have executed this Agreement in duplicate
originals by their proper officers as of the Effective Date.

CUBIST PHARMACEUTICALS, INC.   GILEAD SCIENCES, INC.
By:
 
/s/ S. M. Rocklage
 
By:
 
/s/ John C. Martin    

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Title:   President & CEO   Title:   President & CEO    

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Date:   January 6, 2001   Date:   January 6, 2001    

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48

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EXHIBIT A

CUBIST CLINICAL TRIALS

Core Trials

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  Protocol Number
and Trial Phase

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  Country(ies) in which conducted

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  Primary Endpoint

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[*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]  
[*]   [*] [*]   [*]   [*]   [*] Other Trials             [*]   [*]   [*]   [*]
[*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*]

A–1

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EXHIBIT B

CUBIST MARKS

Mark

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  Country

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  Filing Date

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  Application
Number

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[*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]  
[*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]
  [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]  
[*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]
  [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*]
[*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]  
[*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]
  [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]  
[*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]
  [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*] [*]   [*]   [*]   [*]
[*]   [*]   [*]   [*] [*]   [*]   [*]   [*]

B–1

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EXHIBIT C

PRIMARY DAPTOMYCIN MOLECULE

[*]

C–1

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EXHIBIT D

GILEAD MARKS

[*]

D–1

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EXHIBIT E

COUNTRIES OF THE GILEAD TERRITORY

[*]

E–1

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EXHIBIT F

COUNTRIES OF THE ROFR TERRITORY

[*]

F–1

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EXHIBIT G

SUPPLY AGREEMENT
SUMMARY OF TERMS

[*]

    (4 pages of continuous text omitted here)

G–1

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EXHIBIT H

JOINT PRESS RELEASE

[CUBIST PHARMACEUTICALS LOGO]   LOGO [g368303.jpg] Contacts:    
Cubist Pharmaceuticals, Inc.
 
Gilead Sciences, Inc.
Jennifer LaVin
 
Susan Hubbard, Investors
Senior Director, Corporate Communications
(617) 576-4258
 
(650) 522-5715
jlavin@cubist.com
 
Amy Flood, Media
(650) 522-5643
Noonan/Russo Communications
 
 
Renee Connolly, Media
 
 
(212) 696-4455 ext. 227
 
 
renee@noonanrusso.com
 
 

CUBIST PHARMACEUTICALS AND GILEAD SCIENCES ANNOUNCE
EUROPEAN COMMERCIALIZATION AGREEMENT FOR
INVESTIGATIONAL ANTIBACTERIAL AGENT CIDECINTM

    Cambridge, MA and Foster City, CA, January 7, 2001—Cubist
Pharmaceuticals, Inc. (Nasdaq: CBST) and Gilead Sciences, Inc. (Nasdaq: GILD)
today jointly announced the signing of a licensing agreement for the exclusive
rights to commercialize Cubist's investigational antibacterial drug Cidecin™
(daptomycin for injection) and an oral formulation of daptomycin in 16 European
countries following regulatory approval.

    Gilead has agreed to pay Cubist an up-front licensing fee of $13 million,
and Cubist is entitled to receive additional cash payments of up to $31 million
upon achievement of certain clinical and regulatory milestones. Gilead will also
pay Cubist a fixed royalty on net sales. Cubist will continue to be responsible
for worldwide clinical development of Cidecin, while Gilead will be responsible
for any regulatory filings in the covered territories. Gilead's sales force will
market the products in Europe. Cubist will provide European Medical Science
Liaisons (MSLs) who will support the product by providing medical education
services to infectious disease specialists and other international opinion
leaders.

    "We believe Gilead to be the ideal European marketing partner for Cubist,"
said Scott M. Rocklage, Ph.D., Chairman, President and CEO of Cubist. "With its
international sales force, Gilead is already calling on the identical target
market for Cidecin. We believe this will be a synergistic relationship given
that Gilead's product AmBisome and Cidecin are complementary in therapeutic
focus, allowing for targeted marketing efforts to the same physician audiences.
In addition, Gilead's

H–1

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proven track record of sales performance and experience with European regulatory
authorities provides us with confidence in the company's ability to successfully
market Cidecin to the European hospital community."

    Daptomycin is the first in a new class of investigational drugs called
lipopeptides. Cubist is currently developing IV and oral formulations of
daptomycin to treat serious bacterial infections. In vitro data show daptomycin
has the ability to rapidly kill virtually all Gram-positive bacteria, including
those resistant to current therapies. Cubist has multiple ongoing Phase III
clinical trials of Cidecin, the IV formulation, to evaluate the efficacy and
safety in the treatment of complicated skin and soft tissue infection (cSST),
community-acquired pneumonia (CAP) and complicated urinary tract infection
(cUTI). Phase II trial are also ongoing to investigate the treatment of
bacteremia (BAC) and resistant infections (RRC). Cubist recently announced that
it had completed enrollment in its international Phase III cSST trial and
expects to announce clinical results during the second quarter of 2001. An oral
version of daptomycin is currently in pre-clinical development.

    "Cidecin is an important addition to our portfolio of products for unmet
medical needs," said John C. Martin, Ph.D., President and Chief Executive
Officer of Gilead. "We believe Cidecin possesses a strong worldwide market
potential and are pleased that Cubist has chosen Gilead as its European
commercialization partner."

    Gilead markets AmBisome® (liposomal amphotericin B) for injection in 42
countries worldwide for the treatment of life-threatening systemic fungal
infections. Since the product's European introduction in 1990, Gilead has
successfully grown the market for Ambisome throughout the world. With total 1999
sales of $173 million, AmBisome is the second largest-selling injectable
antifungal product worldwide. Much of the product's growth can be attributed to
Gilead's efforts to increase the number of territories in which AmBisome is
marketed, expand the product label through additional regulatory filings and
inclusion of head-to-head competitive data, and maintain its well established
marketing relationships.

    Cubist Pharmaceuticals is focused on becoming a global leader in the
research, development and commercialization of novel antimicrobial drugs to
combat serious and life-threatening bacterial and fungal infections. Cubist is
evaluating the safety and efficacy of Cidecin™ (daptomycin for injection) in the
EDGE™ (Evaluation of Daptomycin against Gram-positive Entities) clinical trial
program and is engaged in multiple, strategic partnerships, including Novartis
Pharma AG, Merck & Co and Schering-Plough for the discovery and development of
novel antiinfectives. Cubist recently completed the acquisition of TerraGen
Discovery Inc., a private, natural products discovery company with operations in
Vancouver, BC, Canada and Slough, UK.

    Gilead Sciences, headquartered in Foster City, CA, is an independent
biopharmaceutical company that seeks to provide accelerated solutions for
patients and the people who care for them. The Company discovers, develops,
manufactures and commercializes proprietary therapeutics for challenging
infectious diseases (viral, fungal and bacterial infections) and cancer. Gilead
maintains research, development or manufacturing facilities in Foster City, CA,
Boulder, CO, San Dimas, CA, and Cambridge, UK, and sales and marketing
organizations in the United States, Europe and Australia.

    Statements contained herein that are not historical fact may be
forward-looking statements within the meaning of Section 27A of the Securities
Act of 1933 and Section 21E of the Securities Exchange Act of 1934, that are
subject to a variety of risks and uncertainties. There are a number of important
factors that could cause actual results to differ materially from those
projected or suggested in any forward-looking statements made by Cubist or
Gilead. These factors include, but are not limited to: (i) the ability of Cubist
to successfully complete product research and development, including
pre-clinical and clinical studies and commercialization; (ii) the ability of
Cubist and Gilead to obtain required governmental approvals; (iii) the ability
of Cubist to attract and/or maintain manufacturing, sales, distribution and
marketing partners; (iv) the ability of Cubist to develop and commercialize its

H–2

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products before its competitors; and (v) the ability of Gilead to grow or
maintain the market for AmBisome particularly in light of the anticipated
introduction of competitive products. Additional factors that would cause actual
results to differ materially from those projected or suggested in any
forward-looking statements are contained in each company's filings with the
Securities and Exchange Commission, including those factors discussed under the
caption "Risk Factors" for Cubist on Annual Report on Form 10-K/A (file
No. 000-21379) filed on April 3, 2000 and for Gilead on Form 10-K for the year
ended December 31, 1999.

###

For additional information, visit either of the companies' web sites at
www.cubist.com or www.gilead.com.

H–3

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QuickLinks

ARTICLE 1 DEFINITIONS
ARTICLE 2 MANAGEMENT
ARTICLE 4 REGULATORY
EXHIBIT A
CUBIST CLINICAL TRIALS
EXHIBIT B
CUBIST MARKS
EXHIBIT C
PRIMARY DAPTOMYCIN MOLECULE
EXHIBIT D
GILEAD MARKS
EXHIBIT E
COUNTRIES OF THE GILEAD TERRITORY
EXHIBIT F
COUNTRIES OF THE ROFR TERRITORY
EXHIBIT G
SUPPLY AGREEMENT SUMMARY OF TERMS
EXHIBIT H
JOINT PRESS RELEASE
CUBIST PHARMACEUTICALS AND GILEAD SCIENCES ANNOUNCE EUROPEAN COMMERCIALIZATION
AGREEMENT FOR INVESTIGATIONAL ANTIBACTERIAL AGENT CIDECINTM
For additional information, visit either of the companies' web sites at
www.cubist.com or www.gilead.com .