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                                                                   Exhibit 10.10

           PREDIX PHARMACEUTICALS HOLDINGS, INC. EMPLOYMENT AGREEMENT

      EMPLOYMENT AGREEMENT, dated as of the 8th day of August, 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 Dr. Michael Kauffman residing at [ADDRESS] (the
"Employee").

                                   WITNESSETH:

      WHEREAS, the Company desires to employ the Employee as President and Chief
Executive Office ("CEO") 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.

      2. Duties. The Employee shall serve as the President and CEO 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 serve the
Company faithfully, conscientiously and to the best of the Employee's ability
and shall promote the interests and reputation of the Company. 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 fulfill his responsibilities as
President of OutlineMed Inc., a medical software company at 25 Kerr Path,
Newton, Massachusetts, which, at this time, is wholly-owned by the Employee,
provided that such responsibilities do 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.

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      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. The Company shall pay the Employee a base salary at
an annual rate of $300,000.00 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) upon the closing of the transaction in which
the Company shall take ownership of 100% of the shares of Predix Ltd., and after
the Effective Date, the Employee will be eligible for a one-time special bonus
of $30,000.00, to be paid on or before thirty days from the Effective Date; 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 $70,000.00, although the Board
in the exercise of its sole discretion shall determine the actual bonus payment.

            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.

            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

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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 1,069 shares as a grant of Predix Holdings A Common
shares. These shares shall be unrestricted.

The Employee will also be granted 431,572 options to purchase Predix Holdings A
Common shares, vesting over 4 years from September 23, 2002 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.

The Employee will also be granted a further 325,450 options to purchase Predix
Holdings A Common shares, vesting over 4 years from July 31, 2003 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. 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

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                  (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.

            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
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
Section 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

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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 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, (l) 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

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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 instructions 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 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

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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 the 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.

                  (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

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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 for both parties will
be preserved if the Early Resolution Conference requirement is complied with
even if no agreement is reached in the conference.

      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

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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.

            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

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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 continuation of health benefits under COBRA for up to six (6)
months following the Termination Date.

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. Termination of Prior Employment Agreement; Representations and Release.
The Employee acknowledges that he is currently a party to an employment
agreement with one of the Company's wholly owned subsidiaries, Predix
Pharmaceuticals Ltd., dated September 6, 2002 (the "Old Agreement"). The
Employee and the Company agree that the Old Agreement shall terminate effective
immediately upon the Effective Date of this Agreement. The Employee further
confirms and agrees, in consideration for the benefits provided herein, as
follows:

            a. He has received full and final payment of all monies and other
benefits that are due and owing under the Old Agreement;

            b. As of the Effective Date, all rights to payment or benefits of
any kind expire and become null and void. The Employee specifically hereby
releases any rights he may have had or may in the future have to bring a claim
for breach of the Old Agreement or for

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failure of any kind by the Company, its subsidiaries, affiliates, or any of
their officers, directors, employees or agents, to make payments or provide
benefits to him pursuant to the Old Agreement. Nothing in this paragraph shall
be interpreted as limiting the Employee's right to bring a claim for a breach of
this Agreement by the Company; and

            c. The Employee acknowledges and agrees that the Predix US Share
Option Plan has been cancelled and agrees that he has no rights to any of the
equity which may have been due him pursuant to the Old Agreement.

      8. 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.

      9. 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.

      10. 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.

      11. 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 law rules of any state or where the Employee is in fact
required to work.

      12. 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 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.

      13. 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

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<PAGE>

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.

      14. 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 provisions of 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.

      15. 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:

                  Dr. Michael Kauffman
                  [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.

      16. 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.

      17. 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.

      18. 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

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<PAGE>

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/ NIK HAYES                           /s/ MICHAEL G. KAUFFMAN, MD
    -----------------                       ---------------------------
    Nik Hayes                               Employee signature
    Chief Operating Officer

                                            Michael Kauffman, MD
                                            ---------------------------
                                            Print Employee's Name

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