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                                                                   Exhibit 10.13

           PREDIX PHARMACEUTICALS HOLDINGS, INC. EMPLOYMENT AGREEMENT

            EMPLOYMENT AGREEMENT, dated as of the 23rd of November, 2003, (the
"Effective Date") between Predix Pharmaceuticals Holdings, Inc., a Delaware
corporation with its principal place of business at 10 K Gill Street, Woburn, MA
01801 (the "Company"), and Mr. Chen Schor residing at [ADDRESS] (the
"Employee").

                                   WITNESSETH:

            WHEREAS, the Company desires to employ the Employee as Chief
Business Officer ("CBO") of Predix Pharmaceuticals, Inc, and the Employee
desires to accept such employment, all on the terms and conditions specified
herein; and

            WHEREAS, the Employee and the Company desire to set forth in writing
all of their respective duties, rights and obligations with respect to the
Employee's employment by the Company; and

            NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants and obligations hereinafter set forth, the parties hereto, intending
to be legally bound, hereby agree as follows:

            1. Employment. The Company hereby offers to employ the Employee, and
the Employee hereby accepts employment by the Company, in the capacity and upon
the terms and conditions hereinafter set forth. The Date of Employment shall be
no later than 1 March, 2004 and this agreement shall be predicated on the
Company being able to obtain such Visas as are required for the Employee to work
in the United States of America as an employee of the Company, and the company
undertakes to use its reasonable endeavors to obtain such Visas so that they are
effective prior to I" March 2004.

            2. Duties. The Employee shall serve as the CBO for the Company and
any affiliate or subsidiary of the Company determined by the Company's Board of
Directors, and shall perform such duties, functions and responsibilities as are
associated with and incident to that position and as the Company may, from time
to time, require of him. The Employee shall report to the President and CEO of
the Company. The Employee shall serve the Company faithfully, conscientiously
and to the best of the Employee's ability and shall promote the interests and
reputation of the Company under direction of the President and CEO. Unless
prevented by sickness or disability, the Employee shall devote all of the
Employee's time, attention, knowledge, energy and skills, during normal working
hours, and at such other times as the Employee's duties may require, to the
duties of the Employee's employment. The principal place of employment of the
Employee shall be at Employer's Woburn, MA area office and/or such other
location as shall be necessary for the Employee to discharge the Employee's
duties hereunder. The Employee acknowledges that in the course of employment the
Employee may be required, from time to time, to travel on behalf of the Company.
The Company recognizes that the Employee will continue to maintain his
relationships with venture capital funds, investment entities

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or investment banks and may from time to time consult to them on specific
issues, provided that this will not interfere with the Employee's fulfillment of
his duties and obligations to the Company, its affiliates and subsidiaries as
outlined in this Agreement or otherwise.

The Employee's duties shall include but not be limited to the following: (1)
report to the CEO and President; (2) participate as a equal member of the
Executive Team, (3) with the CEO, lead efforts to raise the next and subsequent
equity rounds and to develop the business of the Company in North America,
and/or Europe and/or Israel and/or the Far East, (4) be part of the team
negotiating the outlicensing of the Company's proprietary compounds, (5) act as
the Secretary of the Company's Board of Directors, and as a Observer to the
Board of Directors, (6) Be responsible, supervise, manage and maintain all the
financial and legal aspects and duties of the Company including but not limited
to those specified in the Board Minutes of the Meeting dated 11th August 2003.

            3. Compensation and Benefits. As full and complete compensation for
the Employee's execution and delivery of this Agreement and performance of any
services hereunder, the Company shall pay, grant or provide the Employee, and
the Employee agrees to accept, the following compensation and benefits, which
shall be paid by the Company or any of its affiliates or subsidiaries designated
by the Company:

                  a. Base Salary. With effect from the Date of Employment the
Company shall pay the Employee a base salary at an annual rate of $200,000.00
payable on the 15th and last day of every month, in accordance with the
Company's customary payroll practices that may be adopted or modified from time
to time. On an annual basis or at such other times as the Company may determine,
the Company will review the Employee's performance and determine whether, in its
sole discretion, the Company will increase (but not decrease, except that such
salary may be decreased if in connection with a decrease in the salaries of all
similarly situated Company executives) the Employee's base salary.

                  b. Bonus. The Employee may be eligible for bonuses from the
Company during the course of his employment. The timing and amount of such
bonus(es), if any, shall be in the sole discretion of the Company. The criteria
to be used in determining any such bonus may include, in the Company's
discretion, one or more of the following criteria: individual performance,
performance of specific projects, and the Company's performance. The Employee
will also be eligible for the following specific bonuses: (i) after the
Effective Date, the Employee will be eligible for a one-time special bonus of
$20,000.00, to be paid on January 1st 2004 (the Signing Bonus); and (ii) during
the twelve month period ending July 31, 2004, the Employee will be eligible for
a performance based bonus, to be based upon the Company and the Employee meeting
milestones to be set by the Board of Directors. The target amount of the bonus
in subsection (ii) shall be $40,000.00 prorated for the number of months of
employment, although the Board in the exercise of its sole discretion shall
determine the actual bonus payment.

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                  c. Fringe Benefits. The Company shall afford the opportunity
to participate in any health care, dental, disability insurance, retirement,
savings and any other employee benefits plans, policies or arrangements which
the Company maintains for its employees in accordance with the written terms of
such plans, policies or arrangements, so long as the Employee meets all
applicable eligibility requirements. Nothing in this Agreement shall require the
Company or its affiliates to establish, maintain or continue any benefit plans,
policies or arrangements or restrict the right of the Company or any of its
affiliates to amend, modify or terminate any such benefit plan, policy or
arrangement. In addition to the above-mentioned benefit, the Company agrees to
provide assistance to the Employee by supporting and sponsoring an application
for permanent residency to be made by the Employee.

                  d. Stock and Stock Option Arrangements. All of the Employee's
stock and stock options shall be governed by the applicable stock plan and stock
option or stock agreement, which provisions shall supersede any statements in
this section.

Subject to the approval of the Compensation Committee of the Company's Board of
Directors, the Company shall grant to the Employee an option to purchase shares
of the Company's common stock. Each grant shall be pursuant to the terms and
conditions of the Predix Pharmaceuticals Holdings, Inc. 2003 Stock Incentive
Plan and the Employee's execution of a standard Predix Pharmaceuticals Stock
Option Agreement in the form provided to the Employee by the Company. The
Employee acknowledges having received a copy of the Predix Pharmaceuticals
Holdings, Inc. 2003 Stock Incentive Plan and unexecuted Stock Option Agreements.

The Employee will be granted 350,000 options to purchase Predix Holdings A
Common shares, vesting over 4 years from the Date of Employment with an exercise
price of $0.10 per share. These options will be governed by the Predix
Pharmaceuticals Holdings, Inc. 2003 Stock Incentive Plan and the related option
agreement. The deal valuation per share of A Common Stock is $0.10.

                  e. Expenses. The Employee shall be entitled to reimbursement
or payment of reasonable business expenses in accordance with the Company's
policies, as the same may be amended from time to time in the Company's sole
discretion, following the Employee's submission of appropriate receipts, bills
and/or expense reports to the Company in accordance with such policies.

                  f. Relocation Expenses. The Employee shall be entitled to
reimbursement or payment of reasonable relocation expenses not to exceed $25,000
in accordance with the Company's policies, as the same may be amended from time
to time in the Company's sole discretion, following the Employee's submission of
appropriate receipts, bills and/or expense reports to the Company in accordance
with such policies. Any expense including but not limited to the purchase of
furniture or electrical appliances that is not in accordance with the Company's
relocation policies will be reimbursed and regarded as an increase of the
Signing Bonus as long as the maximum reimbursement per this section 3(f) shall
not exceed $25,000 in total. The Company shall also pay expenses

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in relation to obtaining necessary visa's for the employee to work for the
company in the US.

                  g. Time Off. The Employee shall be entitled to twenty (20) WYN
(What You Need) days per calendar year, without loss or diminution of
compensation. These WYN days shall accrue at the rate of 1.67 WYN days per full
month of service, commencing with the Effective Date of this Agreement. Such WYN
days shall be taken at such time or times consistent with the needs of the
Company's business and in accordance with the Company's policies. The Employee
shall further be entitled to the number of paid holidays, and leaves in
accordance with the Company's policies as such policies may be amended from time
to time or terminated in the Company's sole discretion. The Company currently
allows for eleven (11) paid holidays per calendar year.

            4. Non-Competition, Confidentiality, Discoveries and Works:

                  a. Non-Competition: During the period of the Employee's
employment at the Company and for six (6) months following the termination, for
any reason, of the Employee's employment, the Employee agrees not to compete in
any manner, either directly or indirectly, whether for compensation or
otherwise, with the Company, or to assist any other person or entity to compete
with the Company either:

                        (i) by producing, developing or marketing, or assisting
others to produce, develop or market, or

                        (ii) by accepting employment from or having any other
relationship (including, without limitation, through owning, managing,
operating, controlling or consulting) with any entity: (Y) which produces,
develops or markets, a product, process, or service which is competitive with
those products, processes, or services of the Company, whether existing or
planned for in the future; or (Z) on which the Employee has worked, or
concerning which the Employee has in any manner acquired knowledge of or had
access to Confidential Information (as defined in Section 4(e)(iii) below),
during the three (3) years preceding termination of the Employee's employment.
Except that the Employee may have beneficial ownership of less than 1% of the
outstanding amount of any class of securities listed on a national securities
exchange or quoted on an inter-dealer quotation system, of such a company. This
section 4(a) shall not apply to an investment entity or a venture capital fund
or an investment bank.

                  b. Non-Solicitation: During the period of the Employee's
employment at the Company and for twelve (12) months following the termination,
for any reason, of the Employee's employment, the Employee agrees that the
Employee will not, either on the Employee's own behalf or on behalf of any other
person or entity (other than for the benefit of the Company), directly or
indirectly, (i) solicit any person or entity that is a customer of the Company,
or has been a customer of the Company during the prior twelve (12) months, to
purchase any products or services the Company provides to the customer, or (ii)
interfere with any of the Company's business relationships.

                  c. No-Hire: During the period of the Employee's employment at
the Company and for twelve (12) months following the termination, for any
reason, of

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the Employee's employment, the Employee agrees that the Employee will not,
either on the Employee's own behalf or on behalf of any other person or entity,
directly or indirectly, hire, solicit or encourage to leave the employ of or
engagement by the Company any person who is then an employee or contractor of
the Company or who was an employee or contractor of the Company within six (6)
months of the date of such hiring, soliciting, or encouragement to leave the
Company.

                  d. Geographic Scope: The foregoing restrictions shall apply in
the "Restricted Area" which means:

                        (i) any competitive business anywhere in the world,
given the nature of the Company's business and certain accounts of the Company
are national and international in scope and are not dependent on the geographic
location of the Employee personnel or the business by which they are employed,
and

                        (ii) any location, storefront, address or place of
business where a Covered Customer is present and available for solicitation.

The Employee will not circumvent the purpose of any restriction contained in
Sections 4(a), 4(b) or 4(c) by engaging in business outside the geographic
region covered by the above definition through remote means like telephone,
correspondence or computerized communication. "Covered Customer" means those
customers, entities and/or persons who did business with the Company and that
the Employee either (x) received Confidential Information about in the course of
his/her duties, (y) had contact with within the last twenty-four (24) month
period of employment by the Company, or (z) supervised contact with within the
last twenty-four (24) month period of employment with the Company.

                  e. Confidentiality:

                        (i) During the period of the Employee's employment at
the Company and for all time following the termination, for any reason, of the
Employee's employment, the Employee shall hold all Confidential Information of
the Company in a fiduciary capacity and agrees not to take any action which
would constitute or facilitate the Unauthorized use or disclosure of
Confidential Information.

The Employee further agrees to take all reasonable measures to prevent the
Unauthorized use and disclosure of Confidential Information and to prevent
Unauthorized persons or entities from obtaining or using Confidential
Information. The terms "Confidential Information" and "Unauthorized" shall have
the meanings set forth in Sections 4(e)(iii) and (iv) of this Agreement
respectively.

                        (ii) Promptly upon termination, for any reason, of the
Employee's employment with the Company, the Employee agrees to deliver to the
Company all property and materials within the Employee's possession or control
which belong to the Company or which contain Confidential Information.

                        (iii) As used in this Agreement, the term "Confidential
Information" shall mean trade secrets, confidential or proprietary information,
and all

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other information, documents or materials, owned, developed or possessed by the
Company, its parents, subsidiaries or affiliates, their respective predecessors
and successors, whether in tangible or intangible form, that is not generally
known to the public. Confidential Information includes, but is not limited to,
(a) financial information, (b) products, (c) product and service costs, prices,
profits and sales, (d) new business ideas, (e) business strategies, (f) product
and service plans, (g) marketing plans and studies, (h) forecasts, (i) budgets,
(j) projections, (k) computer programs, (1) data bases and the documentation
(and information contained therein), (m) computer access codes and similar
information, (n) software ideas, (o) know-how, technologies, concepts and
designs, (p) research projects and all information connected with research and
development efforts, (q) records, (r) business relationships, methods and
recommendations, (s) existing or prospective client, customer, vendor and
supplier information (including, but not limited to, identities, needs,
transaction histories, volumes, characteristics, agreements, prices, identities
of individual contacts, and spending, preferences or habits), (t) training
manuals and similar materials used by the Company in conducting its business
operations, (u) skills, responsibilities, compensation and personnel files of
Company employees, directors and independent contractors, (v) competitive
analyses, (w) contracts with other parties, and (x) other confidential or
proprietary information that has not been made available to the general public
by the Company's senior management.

                        (iv) As used in this Agreement, the term "Unauthorized"
shall mean: (a) in contravention of the Company's policies or procedures; (b)
otherwise inconsistent with the Company's measures to protect its interests in
the Confidential Information; (c) in contravention of any lawful instruction or
directive, either written or oral, of a Company employee empowered to issue such
instruction or directive; (d) in contravention of any duty existing under law or
contract; or (e) to the detriment of the Company.

                        (v) In the event that the Employee is requested by any
governmental or judicial authority to disclose any Confidential Information, the
Employee shall give the Company prompt notice of such request (including, by
giving the Company a copy of such request if it is in writing), such that the
Company may seek a protective order or other appropriate relief, and in any such
proceeding the Employee shall disclose only so much of the Confidential
Information as is required to be disclosed.

                  f. Discoveries and Works: All discoveries and works made or
conceived by the Employee during and in the course of his/her employment by the
Company, jointly or with others, that relate to the Company's activities shall
be owned by the Company. The terms "discoveries and works" include, by way of
example, all ideas, discoveries, creations, manuscripts and properties,
innovations, improvements, know-how, inventions, designs, developments,
apparatus, techniques, methods, biological processes, cell lines, laboratory
notebooks and formulae, whether or not patentable or copyrightable, including
all rights to obtain, register, perfect and enforce these proprietary interests.
The Employee shall promptly notify and make full disclosure to, and execute and
deliver any documents requested by, the Company to evidence or better assure
title to such discoveries and works by the Company, assist the Company in
obtaining or

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maintaining for itself at its own expense United States and foreign patents,
copyrights, trade secret protection and other protection of any and all such
discoveries and works, and promptly execute, whether during his/her employment
or thereafter, all applications or other endorsements necessary or appropriate
to maintain patents and other rights for the Company and to protect its title
thereto. Any discoveries and works which, within one (1) year after the
termination of the Employee's employment hereunder, are made, disclosed, reduce
to a tangible or written form or description, or are reduced to practice by the
Employee and which pertain to work performed by the Employee while with, and in
his/her capacity as an Employee of, the Company shall, as between the Employee
and the Company presumed to have been made during the Employee's employment by
the Company.

                  g. Representations, Warranties and Acknowledgements

                        (i) The Employee acknowledges that (a) the Company
considers Confidential Information to be commercially and competitively valuable
to the Company and critical to its success; (b) Unauthorized use or disclosure
of Confidential Information would cause irreparable harm to the Company; and (c)
by this Agreement, the Company is taking reasonable steps to protect its
legitimate interests in its Confidential Information.

                        (ii) The Employee also acknowledges the competitive and
proprietary nature of the Company's business operations. The Employee
acknowledges and agrees that a business will be deemed competitive with the
Company if it engages in a line of business in which it performs any of the
services, conducts research, or develops, manufactures or sells any products
provided or offered by the Company or under development by the Company, or any
similar products or products fulfilling the same function, whether or not
similar, in the Field of Interest (such business to be referred to as a
"competitive business"). The term "Field of Interest" currently means discovery
and development of drugs acting on G Protein Coupled Receptors and Ion Channels.
The Employee further understand that the Company may expand the definition of
its Field of Interest at any time by action of its Board of Directors, which new
definition will be binding upon the Employee ten (10) days after written notice
to the Employee of such change.

The Employee further acknowledges that given the nature of the Company's
business, certain accounts of the Company are national and international in
scope and are not dependent on the geographic location of the Employee personnel
or the business by which they are employed.

                        (iii) The Employee represents and warrants to the
Company that he/she is not a party to any agreement, or non-competition or other
covenant or restriction contained in any agreement, commitment, arrangement or
understanding (whether oral or written), that in any way conflicts with or
limits the Employee's ability to commence or continue to render services to the
Company or that would otherwise limit the Employee's ability to perform all
responsibilities in accordance with the terms and subject to the conditions of
the Employee's employment.

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                        (iv) The Employee acknowledges that certain accounts are
national and international in scope and the location of the Company's customers
is not dependent on the geographic location of the Employee or the Company.

                        (v) The Employee consents and agrees that, during the
Employee's employment with Company and thereafter, the Company may review,
audit, intercept, access and disclose all communications created, received or
sent over the electronic mail and internet access system provided by Company
with or without notice to the Employee and that such review, audit,
interception, access, or disclosure may occur during or after working hours. The
Employee further consents and agrees that the Company may, at any time, access
and review the contents of all computers, computer disks, other data storage
equipment and devices, files, desks, drawers, closets, cabinets and work
stations which are either on Company's premises or which are owned or provided
by Company.

                  h. Remedies: In the event of breach or threatened breach by
the Employee of any provision of Section 4 hereof, the Company shall be entitled
to obtain (i) temporary, preliminary and permanent injunctive relief, in each
case without the posting of any bond or other security, (ii) damages and an
equitable accounting of all earnings, profits and other benefits arising from
such breach, or threatened breach, (iii) recovery of all attorney's fees and
costs incurred by the Company in obtaining such relief, (iv) repayment of any
severance benefits paid to the Employee pursuant to this Agreement or any
severance benefit agreement, plan or arrangement of the Company, and (v) any
other legal and equitable relief to which it may be entitled, including any and
all monetary damages which Company may incur as a result of said breach or
threatened breach. The Company may pursue any remedy available, including
declaratory relief, concurrently or consecutively, in any order, and the pursuit
of one such remedy at any time will not be deemed an election of remedies or
waiver of the right to pursue any other remedy.

                  i. Early Resolution Conference: This Agreement is understood
to be clear and enforceable as written and is executed by both parties on that
basis. However, should the Employee later challenge any provision as unclear,
unenforceable, or inapplicable to activity that the Employee intends to engage
in, the Employee will first notify Company in writing and meet with a Company
representative and a neutral mediator (if the Company elects to retain one at
its expense) to discuss resolution of any disputes between the parties. The
Employee will provide this notification at least fourteen (14) days before the
Employee engages in any activity on behalf of a competing business or engages in
other activity that could foreseeably fall within a questioned restriction. The
failure to comply with this requirement shall waive the Employee's right to
challenge the reasonable scope, clarity, applicability, or enforceability of the
Agreement and its restrictions at a later time. All rights of both parties will
be preserved if the Early Resolution Conference requirement is complied with
even if no agreement is reached in the conference.

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            5. Termination of Employment:

                  a. The Employee is an employee at-will, and either the
Employee or the Company may terminate the employment relationship at any time
for any reason with or without Cause (as defined below). The date upon which the
termination of the Employee's employment becomes effective pursuant to this
Agreement shall be referred to herein as the "Termination Date." The Termination
Date shall be the date upon which any of the following events shall occur:

                        (i) the death of the Employee;

                        (ii) the Disability (as defined below) of the Employee;

                        (iii) the Company's delivery of a written notice to the
Employee of a termination of the Employee's employment for Cause (as defined
below);

                        (iv) the Company's delivery of a written notice to the
Employee of a termination of the Employee's employment Without Cause (as defined
below); or

                        (v) resignation by the Employee.

For purposes of this Agreement, the Employee's employment will not be deemed to
have terminated upon a Change in Control (as defined below).

                  b. For purposes of this Agreement, the "Disability" of the
Employee shall mean the Employee's inability, because of mental or physical
illness or incapacity, whether total or partial, to perform one or more of the
primary duties of the Employee's employment with or without reasonable
accommodation, and which continues for a length of time that exceeds any period
of leave following which the Employee may have a right to be restored to the
same job or to an equivalent job under federal, state or local law.

                  c. For purposes of this Agreement, the term "Cause" shall mean
the Employee's (i) conviction or entry of a plea of guilty or nolo contendere,
with respect to any felony; (ii) commission of any act of willful misconduct,
gross negligence, fraud or dishonesty; (iii) violation of any term of this
Agreement or any written policy of the Company; or (iv) inability to meet the
performance objectives for the respective position. Notwithstanding the
foregoing, the Company shall not make a determination of "Cause" in any case
where the Cause is reasonably curable, in which case the Company shall provide a
reasonable opportunity of not less than ten (10) business days for the Employee
to cure prior to such a determination. In addition, if termination is pursuant
to subsection (iv), a determination of Cause shall only be made after the
Company has undergone a performance management process with the Employee and the
Employee has not shown ability to perform satisfactorily after a period of not
less than thirty (30) days.

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                  d. For purposes of this Agreement, "Without Cause" shall mean
for any reason(s) whatsoever (other than the reasons described in Sections
5(a)(i), 5(a)(ii), 5(a)(iii), and 5(a)(v) hereof).

                  e. The Employee should give the Company reasonable notice when
resigning from the Company. Reasonable notice being defined as two (2) months.

                  f. For purposes of this Agreement, a "Change in Control" of
the Company means a sale, transfer or other disposition of all or substantially
all of the assets of the Company, or the consummation of a merger or
consolidation of the Company or a sale or exchange of capital stock of the
Company, in either case as a result of which the stockholders of the Company
immediately prior to such transaction own, in the aggregate, less than a
majority of the outstanding voting capital stock or equity interests of the
surviving or resulting entity.

            6. Payments Upon Termination of Employment.

                  a. Death or Disability. If the Employee's employment hereunder
is terminated due to the Employee's death or Disability pursuant to Sections
5(a)(i) or (ii) hereof, the Company shall pay or provide to the Employee, the
Employee's designated beneficiary or to the Employee's estate (i) all base
salary pursuant to Section 3(a) hereof and any vacation pay pursuant to Section
3(g) hereof, in each case which has been earned but unpaid as of the Termination
Date; and (ii) any benefits to which the Employee may be entitled under any
employee benefits plan, policy or arrangement pursuant to Section 3(b) hereof
(including, but not limited to, life insurance and disability insurance) in
which he/she is a participant in accordance with the written terms of such plan,
policy or arrangement up to and including the Termination Date.

                  b. Termination for Cause or Resignation. If the Employee's
employment hereunder is terminated by the Company for Cause pursuant to Section
5(a)(iii) or due to the Employee's resignation pursuant to Section 5(a)(v), the
Company shall pay or provide to the Employee (i) all base salary pursuant to
Section 3(a) hereof and any vacation pay pursuant to Section 3(g) hereof, in
each case which has been earned but unpaid as of the Termination Date; and (ii)
any benefits to which the Employee may be entitled under any employee benefits
plan, policy or arrangement pursuant to Section 3(b) hereof in which he/she is a
participant in accordance with the written terms of such plan, policy or
arrangement up to and including the Termination Date

                  c. Termination Without Cause. If the Employee's employment
hereunder is terminated by the Company Without Cause pursuant to Section
5(a)(iv), the Company shall award the Employee severance pay, The severance pay
benefit shall be the continuation of the Employee's then current base pay for a
period of six (6) months.

Upon termination, the Employee may be eligible to reinstate health insurance
benefits pursuant to COBRA. If the Employee's employment hereunder is terminated
by the Company Without Cause pursuant to Section 5(a)(iv) and Employee is
eligible for and elects COBRA coverage, the Company will pay the Employee's
premiums for

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continuation of health benefits under COBRA for up to six (6) months following
the Termination Date, provided however that the employee shall be entitled to
and does in fact remain within the United States and has not taken subsequent
employment where such health insurance benefits are available.

In order to be eligible to receive any severance payment or medical benefits
pursuant to this paragraph 6, the Employee must sign, prior to receiving such
Severance Payment, a valid release and waiver of all claims against the Company
relating to the Employee's employment or the termination thereof, in a format to
be determined by the Company and must continue to comply with the provisions of
Section 4. No payment shall be made hereunder until at least eight (8) days
following the execution and delivery by the Employee of the valid release and
waiver.

                  d. No Other Payments. Except as provided in this Section 6,
the Employee shall not be entitled to receive any other payments or benefits
from the Company due to the termination of the Employee's employment, including
but not limited to, any employee benefits under any of the Company's employee
benefits plans or arrangements (other than at the Employee's expense under the
Consolidated Omnibus Budget Reconciliation Act of 1985 or pursuant to the
written terms of any pension benefit plan in which the Employee is a participant
in which the Company may have in effect from time to time) or any right to
severance benefits.

            7. Deductions and Withholding. The Employee agrees that the Company
shall withhold from any and all compensation payable under this Agreement all
federal, state, local and/or other taxes which the Company determines are
required to be withheld under applicable statutes and/or regulations from time
to time in effect and all amounts required to be deducted in respect of the
Employee's coverage by and participation in applicable Employee benefit plans,
policies or arrangements.

            8. Entire Agreement. This Agreement embodies the entire agreement of
the parties with respect to the Employee's employment and supersedes any other
prior oral or written agreements between the Employee and the Company and its
affiliates. This Agreement may not be changed or terminated orally but only by
an agreement in writing signed by the parties hereto.

            9. Waiver. The waiver by the Company of a breach of any provision of
this Agreement by the Employee shall not operate or be construed as a waiver of
any subsequent breach by the Employee. The waiver by the Employee of a breach of
any provision of this Agreement by the Company shall not operate or be construed
as a waiver of any subsequent breach by the Company.

            10. Governing Law. This Agreement shall be governed by, and
construed in accordance with, the laws of the Commonwealth of Massachusetts,
without regard to the choice of laws rules of any state or where the Employee is
in fact required to work.

            11. Jurisdiction. Any legal suit, action or proceeding against any
party hereto arising out of or relating to this Agreement shall be brought
solely in the courts of

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the Commonwealth of Massachusetts or of the United States of America for the
District of Massachusetts and each party hereto waives any objection which it
may now or hereafter have to the laying of venue of any such suit, action or
proceeding and each party hereto irrevocably submits to the jurisdiction of any
such court in any suit, action or proceeding.

            12. Assignability. The obligations of the Employee may not be
delegated and, except as expressly provided in Section 6(a) relating to the
designation of beneficiaries, the Employee may not, without the Company's
written consent thereto, assign, transfer, convey, pledge, encumber, hypothecate
or otherwise dispose of this Agreement or any interest therein. Any such
attempted delegation or disposition shall be null and void and without effect.
The Company and the Employee agree that this Agreement and all of the Company's
rights and obligations hereunder may be assigned or transferred by the Company
to and may be assumed by and become binding upon and may inure to the benefit of
any affiliate of or successor to the Company. The term "successor" shall mean
(with respect to the Company or any of its subsidiaries) any other corporation
or other business entity which, by merger, consolidation, purchase of the
assets, or otherwise, acquires all or a material part of the assets of the
Company. Any assignment by the Company of its rights or obligations hereunder to
any affiliate of or successor to the Company shall not be a termination of
employment for purposes of this Agreement.

            13. Severability. If any provision of this Agreement as applied to
either party or to any circumstances shall be adjudged by a court of competent
jurisdiction or arbitrator to be void or unenforceable, the same shall in no way
affect any other provision of this Agreement or the validity or enforceability
of this Agreement. If any court or arbitrator construes any of the provisions of
Section 4 hereof, or any part thereof, to be unreasonable because of the
duration of such provision or the geographic or other scope thereof, such court
or arbitrator may reduce the duration or restrict the geographic or other scope
of such provision and enforce such provision as so reduced or restricted.

            14. Notices. All notices to the Employee hereunder shall be in
writing and shall be delivered personally, sent by overnight courier or sent by
registered or certified mail, return receipt requested, to:

                  Mr. Chen Schor
                  [ADDRESS]

All notices to the Company hereunder shall be in writing and shall be delivered
personally, sent by overnight courier or sent by registered or certified mail,
return receipt requested, to:

                  Predix Pharmaceuticals Holdings, Inc.
                  10 K Gill Street
                  Woburn, MA 01801
                  Attention: President and CEO

Either party may change the address to which notices shall be sent by sending
written notice of such change of address to the other party.

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<PAGE>

            15. Section Headings. The section headings contained in this
Agreement are for reference purposes only and shall not affect in any way the
meaning or interpretation of this Agreement.

            16. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same instrument.

            17. Voluntary Agreement. The Employee acknowledges that before
entering into this Agreement, the Employee has had the opportunity to consult
with any attorney or other advisor of his/her choice, and that this Section 18
of this Agreement constitutes advice from the Company to do so if he/she
chooses. The Employee further acknowledges that he/she has read and understands
this Agreement and has entered into this Agreement of his/her own free will, and
that no promises or representations have been made to him/her by any person to
induce him/her to enter into this Agreement other than the express terms set
forth herein.

            IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the date first above written.

PREDIX PHARMACEUTICALS HOLDINGS, INC.         EMPLOYEE

By. /s/ MICHAEL G. KAUFFMAN, MD               /s/ CHEN SCHOR
    ------------------------------------      ---------------------
    Michael Kauffman, MD, PhD                 Employee signature
    President & Chief Executive Officer       Chen Schor

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