Document:

<PAGE>

                                                                   Exhibit 10.10

                              K.O. Technology, Inc.
                  531 Hammond Street o Chestnut Hill, MA 02167
                           Tel: 739-1182 Fax: 739-1183

March 15, 1993

Vince Stanton
32 Royal Road
Belmont, MA 02178

Dear Vince:

It gives me great pleasure to extend to you a job offer to become Senior
Scientist for K.O. Technology.

As you know, this startup is based on technology and ideas developed by David
Housman. Our company has been established and we are currently in the process of
making a rapid transition to full-fledged, operational status.

Clearly, there are a number of issues which should be discussed as part of the
offer. First, we are happy to extend a salary of $85,000 to you. In addition, we
are prepared to offer you 4% of the company's equity post-first round financing
on a five year vesting schedule. The company will also have health insurance and
obtain coverage for you. When it is appropriate the company will initiate a
pension program and offer you inclusion in it.

This offer is subject to the closing of our financing which we believe will
occur by the end of March. Our mutual obligations to each other will commence
upon completion of financing.

Please don't hesitate to contact me if you have any questions about any part of
this offer. We very much hope that you will join our team and look forward to
working with you.

Best wishes,

K.O. Technology, Inc.

By:   /s/  John J. Kao
   ----------------------------------

Its:  Chief Executive Officer
    ---------------------------------

Read and agreed to:

Vince Stanton                 Date

      /s/  Vince Stanton            3/15/93
--------------------------------------------------
<PAGE>

                                VARIAGENICS, INC.

                     Invention and Non-Disclosure Agreement

This Agreement is made between VARIAGENICS, INC., a Delaware corporation
(hereinafter referred to collectively with its affiliates and subsidiaries as
the "Company"), and Mr. Vincent P. Stanton, Jr. (the "Employee"). In
consideration of the employment or the continued employment of the Employee
by the Company, the Company and the Employee agree as follows:

1.    Proprietary Information.

(a)   The Employee agrees that all information, whether or not in writing, of a
      private, secret or confidential nature concerning the Company's business,
      business relationships or financial affairs (collectively, "Proprietary
      Information") is and shall be the exclusive property of the Company. By
      way of illustration, but not limitation, Proprietary Information may
      include inventions, products, processes, methods, techniques, formulas,
      compositions, compounds, projects, developments, plans, research data,
      clinical data, financial data, personnel data, computer programs, customer
      and supplier lists, and contacts at or knowledge of customers or
      prospective customers of the Company. The Employee will not disclose any
      Proprietary Information to any person or entity other than employees of
      the Company or use the same for any purposes (other than in the
      performance of his/her duties as an employee of the Company) without
      written approval by an officer of the Company, either during or after
      his/her employment with the Company, unless and until such Proprietary
      Information has become public knowledge without fault by the Employee.

(b)   The Employee agrees that all files, letters, memoranda, reports, records,
      data, sketches, drawings, laboratory notebooks, program listings, or other
      written, photographic, or other tangible material containing Proprietary
      Information, whether created by the Employee or others, which shall come
      into his/her custody or possession, shall be and are the exclusive
      property of the Company to be used by the Employee only in the performance
      of his/her duties for the Company. All such materials or copies thereof
      and all tangible property of the Company in the custody or possession of
      the Employee shall be delivered to the Company, upon the earlier of: (i) a
      request by the Company or (ii) termination of his/her employment. After
      such delivery, the Employee shall not retain any such materials or copies
      thereof or any such tangible property.

(c)   The Employee agrees that his/her obligation not to disclose or to use
      information and materials of the types set forth in paragraphs (a) and (b)
      above, and his/her obligation to return materials and tangible property,
      set forth in paragraph (b) above, also extends to such types of
      information, materials and tangible property of customers of the Company
      or suppliers to the Company or other third parties who may have disclosed
      or entrusted the same to the Company or to the Employee.

<PAGE>

2.    Developments.

(a)   The Employee will make full and prompt disclosure to the Company of all
      inventions, improvements, discoveries, methods, developments, software,
      and works of authorship, whether patentable or not, which are created,
      made, conceived or reduced to practice by him/her or under his/her
      direction or jointly with others during his/her employment by the Company,
      whether or not during normal working hours or on the premises of the
      Company (all of which are collectively referred to in this Agreement as
      "Developments").

(b)   The Employee agrees to assign and does hereby assign to the Company (or
      any person or entity designated by the Company) all his/her right, title
      and interest in and to all Developments and all related patents, patent
      applications, copyrights and copyright applications. However, this
      paragraph 2(b) shall not apply to Developments which do not relate to the
      present or planned business or research and development of the Company and
      which are made and conceived by the Employee not during normal working
      hours, not on the Company's premises and not using the Company's tools,
      devices, equipment or Proprietary Information. The Employee understands
      that, to the extent this Agreement shall be construed in accordance with
      the laws of any state which precludes a requirement in an employee
      agreement to assign certain classes of inventions made by an employee,
      this paragraph 2(b) shall be interpreted not to apply to any invention
      which a court rules and/or the Company agrees falls within such classes.
      The Employee also hereby waives all claims to moral rights in any
      Developments.

(c)   The Employee agrees to cooperate fully with the Company, both during and
      after his/her employment with the Company, with respect to the
      procurement, maintenance and enforcement of copyrights, patents and other
      intellectual property rights (both in the United States and foreign
      countries) relating to Developments. The Employee shall sign all papers,
      including, without limitation, copyright applications, patent
      applications, declarations, oaths, formal assignments, assignments of
      priority rights, and powers of attorney, which the Company may deem
      necessary or desirable in order to protect its rights and interests in any
      Development. The Employee further agrees that if the Company is unable,
      after reasonable effort, to secure the signature of the Employee on any
      such papers, any executive officer of the Company shall be entitled to
      execute any such papers as the agent and the attorney-in-fact of the
      Employee, and the Employee hereby irrevocably designates and appoints each
      executive officer of the Company as his/her agent and attorney-in-fact to
      execute any such papers on his/her behalf, and to take any and all actions
      as the Company may deem necessary or desirable in order to protect its
      rights and interests in any Development, under the conditions described in
      this sentence.

(d)   Any publications, texts, or other creative writing endeavors unrelated to
      the Company's Business shall be outside the field of this Agreement and
      the provisions of section 2(b)

(e)   Business concepts, models plans, relationships, and other related assets
      developed by the Employee prior to this Agreement related to the topic of
      off-balance sheet drug

                                      -2-
<PAGE>

      development and the management and financing thereof, hereinafter referred
      to as "Off Balance Sheet Drug Development Plans" shall be outside the
      field of this Agreement and the provisions of section 2(b).

3.    Other Agreements.

The Employee hereby represents that, except as the Employee has disclosed in
Exhibit 1 to this Agreement or in writing to the Company, the Employee is not
bound by the terms of any agreement with any previous employer or other party to
refrain from using or disclosing any trade secret or confidential or proprietary
information in the course of his/her employment with the Company or to refrain
from competing, directly or indirectly, with the business of such previous
employer or any other party, or which would restrict his/her ability to accept
employment or perform work for the Company. The Employee further represents that
his/her performance of all the terms of this Agreement and as an employee of the
Company does not and will not breach any agreement to keep in confidence
proprietary information, knowledge or data acquired by the Employee in
confidence or in trust prior to his/her employment with the Company, and the
Employee will not disclose to the Company or induce the Company to use any
confidential or proprietary information or material belonging to any previous
employer or others.

4.    United States Government Obligations.

The Employee acknowledges that the Company from time to time may have agreements
with the other persons or with the United States Government, or agencies
thereof, which impose obligations or restrictions on the Company regarding
inventions made during the course of work under such agreements or regarding the
confidential nature of such work. The Employee agrees to be bound by all such
obligations and restrictions which are made known to the Employee and to take
all action necessary to discharge the obligations of the Company under such
agreements.

5.    Employment Status.

The Employee understand that this Agreement does not constitute a contract of
employment and does not imply that his/her employment will continue for any
period of time.

6.    Miscellaneous.

(a)   The invalidity or unenforceability of any provision of this Agreement
      shall not affect the validity or enforceability of any other provision of
      this Agreement.

(b)   This Agreement supersedes all prior agreements, written or oral, between
      the Employee and the Company relating to the subject matter of this
      Agreement. This Agreement may not be modified, changed or discharged in
      whole or in part, except by an agreement in writing signed by the Employee
      and the Company. The Employee agrees that any change or changes in his/her
      duties, salary or compensation after the signing of this Agreement shall
      not affect the validity or scope of this Agreement.

                                      -3-
<PAGE>

(c)   No delay or omission by the Company in exercising any right under this
      Agreement will operate as a waiver of that or any other right. A waiver or
      consent given by the Company on any one occasion is effective only in that
      instance and will not be construed as a bar to or waiver of any right on
      any other occasion.

(d)   The Employee expressly consents to be bound by the provisions of this
      Agreement for the benefit of the Company or any subsidiary or affiliate
      thereof to whose employ the Employee may be transferred without the
      necessity that this Agreement be re-signed at the time of such transfer.

(e)   The restrictions contained in this Agreement are necessary for the
      protection of the business and goodwill of the Company and are considered
      by the Employee to be reasonable for such purpose. The Employee agrees
      that any breach of this Agreement is likely to cause the Company
      substantial and irrevocable damage and therefore, in the event of any such
      breach, the Employee agrees that the Company, in addition to such other
      remedies which may be available, shall be entitled to specific performance
      and other injunctive relief.

(f)   This Agreement is governed by and will be construed as a sealed instrument
      under and in accordance with the laws of the Commonwealth of
      Massachusetts. Any action, suit, or other legal proceeding which is
      commenced to resolve any matter arising under or relating to any provision
      of this Agreement shall be commenced only in a court of the Commonwealth
      of Massachusetts (or, if appropriate, a federal court located within
      Massachusetts), and the Company and the Employee each consents to the
      jurisdiction of such a court.

THE EMPLOYEE ACKNOWLEDGES THAT HE/SHE HAS CAREFULLY READ THIS AGREEMENT AND
UNDERSTANDS AND AGREES TO ALL OF THE PROVISIONS IN THIS AGREEMENT.

WITNESS:

VARIAGENICS, INC.

Date:         3/10/00                    By:  /s/ Taylor J. Crouch
     -----------------------                  ------------------------
                                              Taylor J. Crouch
                                              President & CEO

By Employee:

Date:         3/10/00                     By: /s/ Vincent P. Stanton Jr.
     ------------------------                 -------------------------
                                              Vincent P. Stanton Jr.

                                      -4-
<PAGE>

                     Invention and Non-Disclosure Agreement

                                Other Agreements

Pursuant to section 3 of this Agreement, the following is a list of pertinent
agreements between the Employee and previous employers or other parties:

                  |X|   None
                  |_|   As shown below

By:  VARIAGENICS, INC.:                   By:  Employee:

/s/ Taylor J. Crouch                      /s/ Vincent P. Stanton, Jr.
----------------------------              ------------------------------

Dated: 3/10/00                            Dated: 3/10/00
      ----------------------                     -----------------------

                                      -5-<PAGE>

                                                                   Exhibit 10.11

December 23, 1998

Richard P. Shea
52 Margin St.
Cohasset, MA 02025

tel: (781) 383-2384

Dear Rick:

On behalf of VARIAGENICS, I am writing to formally extend to you an offer of
employment in the position of Vice President, Finance. In addition to the formal
Letter Agreement which is attached, I wanted to communicate to you our sense of
the Company's opportunity and your role in shaping our future.

VARIAGENICS' mission is the development of novel pharmaceutical products
targeted to the normal genetic variance of human populations. Through our
marketing alliance with Quintiles (and others), and through direct marketing of
our technologies, capabilities, and intellectual property to biopharmaceutical
companies, we expect to continue building a position of leadership in the
application of genomics to drug development and we expect to profit both from
providing contract pharmacogenomic services, and from participating in the
successful development of new pharmaceutical products.

Our vision is for a Company that is not only a leader in innovative strategies
for drug development, but also a leader in innovative business practices that
optimize the return to our shareholders and employees. To this end, we must
function as a multi disciplinary team. We believe you can contribute
substantially to the success of the Company, and are looking forward to having
you join this team.

Specifically, your roles and responsibilities will be:

(1)   Manage the Company's finances including accounting, purchasing, accounts
      receivable, audit, leases, and investments. Ensure that the Company
      maintains best practices in all of our financial practices including
      implementation of project-based cost accounting and reimbursement
      procedures and management information systems.

(2)   Manage the Company's corporate documents, stock issuances, and
      communication with shareholders as Secretary of the Corporation.

(3)   Participate with the Company's Business Development and Marketing teams to
      complete corporate alliances and sales of the Company's products.
      Responsibilities may include cost analysis, financial projections, and
      negotiations on the financial terms of agreements.

(4)   Participate with the President & CEO to complete corporate financings.
      Responsibilities may include developing strategy, preparing financial
      projections and business plans, building relationships with investment
      banks, investors, and financial analysis, and representing the Company at
      meetings and conferences.
<PAGE>

Richard Shea
December 23, 1998
Page 2

(5)   Manage Operations (with Eleonora Brown, Director of Operations) including
      facilities, human resources, and administration.

Your direct reports at this time will be Eleonora Brown, Director of Operations
and Kathy Kreiter, Controller.

I have attached several documents related to your employment at VARIAGENICS:

      A "Terms and Conditions" Agreement describing the standard terms of
      employment at VARIAGENICS.

      An "Invention and Non-Disclosure Agreement" required of all employees.

      A draft Stock Option Agreement. (The formal agreement requires board
      approval.) As we discussed, I will propose to the Board that vesting of
      options be accelerated upon acquisition of the Company.

Please review these documents and contact Becky Levin or myself with any
questions. I look forward to completing these agreements and welcoming you onto
our team. Best wishes.

Sincerely,

/s/ Fred D. Ledley, M.D.

Fred D. Ledley, M.D.
President & CEO
<PAGE>

                                VARIAGENICS, INC.

                              TERMS AND CONDITIONS

The following are the terms and conditions of your employment with VARIAGENICS,
INC.

1.    Position.

The Company agrees to employ you in the position of Vice President, Finance and
Administration. You will report initially to Fred D. Ledley, M.D., President &
Chief Executive Officer. As you progress with the Company, your position and
location are subject to change at the sole discretion of the Company. Should you
be promoted or reassigned to functions other than your present functions, the
terms of this agreement and the other agreements incorporated herein shall
continue to apply in full force.

During your employment, you shall devote your full business time and energies to
the affairs of VARIAGENICS, and shall not undertake any other employment or
accept financial remuneration outside your business time from any person or
entity in the biotechnology industry, without the expressed written consent of
the President and Chief Executive Officer.

2.    Starting Date/Nature of Relationship.

It is expected that your employment will start on or before February 2, 1999. We
expect that your performance will be reviewed at least annually around the
anniversary of your start date. These terms and conditions shall not be
construed to create an express or implied employment contract for a specific
period of time. Either you or the Company may terminate the employment
relationship at any time for any reason with or without notice.

3.    Compensation.

(a)   Your initial gross salary will be $150,000 with performance based bonuses
      of $30,000 paid upon completion of mutually agreed milestones. Payroll is
      currently paid biweekly.

(b)   You will be offered an agreement entitling you to purchase 40,000 shares
      of VARIAGENICS, INC. common stock for $0.64 per share. Of these, 20% shall
      vest after one year, and the remainder shall vest monthly over the ensuing
      48 months, 1/60 of the total each month, pursuant to a "Stock Option
      Agreement" substantially in the form of the document attached hereto as
      Exhibit A.

(c)   The Company may from time to time authorize bonuses comprising cash and/or
      additional stock options. You will be eligible for consideration of such
      bonuses based on your annual performance review, team performance, and the
      Company's overall financial condition.
<PAGE>

Terms and Conditions
Page 2

(d)   The Company shall reimburse you for all reasonable and necessary expenses
      incurred or paid by in connection with, or related to, the performance of
      services to the Company in accordance with Company policies in effect from
      time to time.

4.    Benefits.

As a full-time employee of the Company, you are entitled to receive such
benefits as are generally provided other full-time Company employees at your
level in accordance with the policies in effect. The Company currently provides
the following benefits: (i) comprehensive health insurance, (ii) dental
insurance, (iii) life insurance, (iv) short term disability insurance, (v) long
term disability insurance, (vi) three weeks paid vacation (accrued on a monthly
basis), (vii) four floating holidays, (viii) six fixed holidays, and (ix) either
free parking near the Company or a T pass. The Company reserves the right to
change, add or cease any particular benefit without notice at its sole
discretion.

5.    Confidentiality.

The Company considers the protection of its confidential information and
proprietary materials to be very important. Therefore, as a condition of your
employment, you and the Company will become parties to an "Invention and
Non-Disclosure Agreement" substantially in the form of the document attached
hereto as Exhibit B.

6.    Workplace.

The Company considers the safety and quality of the workplace to be very
important. You are expected to be familiar with, and abide by, the Company's
safety policies. You are also expected to contribute to creating a working
environment that is both conducive to fostering the business of the Company and
in which respect for the rights of all individuals is maintained.

7.    Non-competition.

For one year following termination of your employment with the Company for any
reason, you shall not canvass, solicit or accept any business which directly
competes with the Company's business from any of the Company's current or former
clients or assist others to open or operate a Competing Business.

8.    Anti-Piracy of Employees.

During your employment with the Company, and for a period of twelve (12) months
thereafter, you shall not, directly or indirectly, entice, solicit or encourage
any Company employee to leave the employ of the Company, nor shall you, directly
or indirectly, be involved in the recruitment of any Company employee.

9.    General.
<PAGE>

Terms and Conditions
Page 2

(a)   This letter, together with fully executed versions of the attached
      documents will constitute our entire agreement as to your employment by
      the Company and will supersede any prior agreements or understandings,
      whether in writing or oral.

(b)   This letter shall be governed by the laws of the Commonwealth of
      Massachusetts.

(c)   Should any provision or term of this Agreement be held to be invalid,
      illegal or unenforceable, in whole or part, such invalidity, illegality,
      or unenforceability shall not affect the validity, legality or
      enforceability of any other provision of this Agreement, and to the extent
      permissible by law, the parties agree that a court shall have the power to
      amend such specific provision so that it can be enforced to the fullest
      extent permissible by law.

(d)   This offer of employment is conditioned upon execution of an Invention and
      Non-disclosure Agreement substantially in the form attached.

(e)   You hereby acknowledge that you have had adequate opportunity to review
      these terms and conditions and to reflect upon and consider the terms and
      conditions of this Agreement. You further acknowledge that you fully
      understand its terms and have voluntarily executed this Agreement.

This offer of employment will expire on January 1, 1999 unless sooner revoked by
the Company or accepted by you prior to such date. You may accept this offer of
employment, and the terms and conditions thereof, by signing this letter, and
returning it to the Company within the designated time frame.

WITNESS:

VARIAGENICS, INC.

By:   /s/ Fred D. Ledley, M.D.            Date:  12/23/98
      --------------------------------          -----------------------
      Fred D. Ledley, M.D.
      President & CEO

By Employee:

By:   /s/ Richard P. Shea                 Date:            12/23/98
      --------------------------------          -----------------------
      Richard P. Shea
<PAGE>

                                    Exhibit B

                     INVENTION AND NON-DISCLOSURE AGREEMENT

This Agreement is made between VARIAGENICS, INC., a Delaware corporation
(hereinafter referred to collectively with its subsidiaries as the "Company"),
and Richard P. Shea (the "Employee"). In consideration of the employment or the
continued employment of the Employee by the Company, the Company and the
Employee agree as follows:

1.    Proprietary Information.

(a)   The Employee agrees that all information, whether or not in writing, of a
      private, secret or confidential nature concerning the Company's business,
      business relationships or financial affairs (collectively, "Proprietary
      Information") is and shall be the exclusive property of the Company. By
      way of illustration, but not limitation, Proprietary Information may
      include inventions, products, processes, methods, techniques, formulas,
      compositions, compounds, projects, developments, plans, research data,
      clinical data, financial data, personnel data, computer programs, customer
      and supplier lists, and contacts at or knowledge of customers or
      prospective customers of the Company. The Employee will not disclose any
      Proprietary Information to any person or entity other than employees of
      the Company or use the same for any purposes (other than in the
      performance of his/her duties as an employee of the Company) without
      written approval by an officer of the Company, either during or after
      his/her employment with the Company, unless and until such Proprietary
      Information has become public knowledge without fault by the Employee.

(b)   The Employee agrees that all files, letters, memoranda, reports, records,
      data, sketches, drawings, laboratory notebooks, program listings, or other
      written, photographic, or other tangible material containing Proprietary
      Information, whether created by the Employee or others, which shall come
      into his/her custody or possession, shall be and are the exclusive
      property of the Company to be used by the Employee only in the performance
      of his/her duties for the Company. All such materials or copies thereof
      and all tangible property of the Company in the custody or possession of
      the Employee shall be delivered to the Company, upon the earlier of: (i) a
      request by the Company or (ii) termination of his/her employment. After
      such delivery, the Employee shall not retain any such materials or copies
      thereof or any such tangible property.

(c)   The Employee agrees that his/her obligation not to disclose or to use
      information and materials of the types set forth in paragraphs (a) and (b)
      above, and his/her obligation to return materials and tangible property,
      set forth in paragraph (b) above, also extends to such types of
      information, materials and tangible property of customers of the Company
      or suppliers to the Company or other third parties who may have disclosed
      or entrusted the same to the Company or to the Employee.

2.    Developments.
<PAGE>

Invention and Non-disclosure Agreement
Page 2

(a)   The Employee will make full and prompt disclosure to the Company of all
      inventions, improvements, discoveries, methods, developments, software,
      and works of authorship, whether patentable or not, which are created,
      made, conceived or reduced to practice by him/her or under his/her
      direction or jointly with others during his/her employment by the Company,
      whether or not during normal working hours or on the premises of the
      Company (all of which are collectively referred to in this Agreement as
      "Developments").

(b)   The Employee agrees to assign and does hereby assign to the Company (or
      any person or entity designated by the Company) all his/her right, title
      and interest in and to all Developments and all related patents, patent
      applications, copyrights and copyright applications. However, this
      paragraph 2(b) shall not apply to Developments which do not relate to the
      present or planned business or research and development of the Company and
      which are made and conceived by the Employee not during normal working
      hours, not on the Company's premises and not using the Company's tools,
      devices, equipment or Proprietary Information. The Employee understands
      that, to the extent this Agreement shall be construed in accordance with
      the laws of any state which precludes a requirement in an employee
      agreement to assign certain classes of inventions made by an employee,
      this paragraph 2(b) shall be interpreted not to apply to any invention
      which a court rules and/or the Company agrees falls within such classes.
      The Employee also hereby waives all claims to moral rights in any
      Developments.

(c)   The Employee agrees to cooperate fully with the Company, both during and
      after his/her employment with the Company, with respect to the
      procurement, maintenance and enforcement of copyrights, patents and other
      intellectual property rights (both in the United States and foreign
      countries) relating to Developments. The Employee shall sign all papers,
      including, without limitation, copyright applications, patent
      applications, declarations, oaths, formal assignments, assignments of
      priority rights, and powers of attorney, which the Company may deem
      necessary or desirable in order to protect its rights and interests in any
      Development. The Employee further agrees that if the Company is unable,
      after reasonable effort, to secure the signature of the Employee on any
      such papers, any executive officer of the Company shall be entitled to
      execute any such papers as the agent and the attorney-in-fact of the
      Employee, and the Employee hereby irrevocably designates and appoints each
      executive officer of the Company as his/her agent and attorney-in-fact to
      execute any such papers on his/her behalf, and to take any and all actions
      as the Company may deem necessary or desirable in order to protect its
      rights and interests in any Development, under the conditions described in
      this sentence.

3.    Other Agreements.

The Employee hereby represents that, except as the Employee has disclosed in
Exhibit 1 to this Agreement or in writing to the Company, the Employee is not
bound by the terms of any agreement with any previous employer or other party to
refrain from using or disclosing any trade secret or confidential or proprietary
information in the course of his/her employment with the Company or to refrain
from competing, directly or indirectly, with the business of such

<PAGE>

Invention and Non-disclosure Agreement
Page 3

previous employer or any other party, or which would restrict his/her ability to
accept employment or perform work for the Company. The Employee further
represents that his/her performance of all the terms of this Agreement and as an
employee of the Company does not and will not breach any agreement to keep in
confidence proprietary information, knowledge or data acquired by the Employee
in confidence or in trust prior to his/her employment with the Company, and the
Employee will not disclose to the Company or induce the Company to use any
confidential or proprietary information or material belonging to any previous
employer or others.

4.    United States Government Obligations.

The Employee acknowledges that the Company from time to time may have agreements
with other persons or with the United States Government, or agencies thereof,
which impose obligations or restrictions on the Company regarding inventions
made during the course of work under such agreements or regarding the
confidential nature of such work. The Employee agrees to be bound by all such
obligations and restrictions which are made known to the Employee and to take
all action necessary to discharge the obligations of the Company under such
agreements.

5.    Employment Status.

The Employee understand that this Agreement does not constitute a contract of
employment and does not imply that his/her employment will continue for any
period of time.

6.    Miscellaneous.

(a)   The invalidity or unenforceability of any provision of this Agreement
      shall not affect the validity or enforceability of any other provision of
      this Agreement.

(b)   This Agreement supersedes all prior agreements, written or oral, between
      the Employee and the Company relating to the subject matter of this
      Agreement. This Agreement may not be modified, changed or discharged in
      whole or in part, except by an agreement in writing signed by the Employee
      and the Company. The Employee agrees that any change or changes in his/her
      duties, salary or compensation after the signing of this Agreement shall
      not affect the validity or scope of this Agreement.

(c)   This Agreement will be binding upon the Employee's heirs, executors and
      administrators and will inure to the benefit of the Company and its
      successors and assigns.

(d)   No delay or omission by the Company in exercising any right under this
      Agreement will operate as a waiver of that or any other right. A waiver or
      consent given by the Company on any one occasion is effective only in that
      instance and will not be construed as a bar to or waiver of any right on
      any other occasion.

(e)   The Employee expressly consents to be bound by the provisions of this
      Agreement for the benefit of the Company or any subsidiary or affiliate
      thereof to whose employ the Employee may be transferred without the
      necessity that this Agreement be re-signed at the time of such transfer.
<PAGE>

Invention and Non-disclosure Agreement
Page 4

(f)   The restrictions contained in this Agreement are necessary for the
      protection of the business and goodwill of the Company and are considered
      by the Employee to be reasonable for such purpose. The Employee agrees
      that any breach of this Agreement is likely to cause the Company
      substantial and irrevocable damage and therefore, in the event of any such
      breach, the Employee agrees that the Company, in addition to such other
      remedies which may be available, shall be entitled to specific performance
      and other injunctive relief.

(g)   This Agreement is governed by and will be construed as a sealed instrument
      under and in accordance with the laws of the Commonwealth of
      Massachusetts. Any action, suit, or other legal proceeding which is
      commenced to resolve any matter arising under or relating to any provision
      of this Agreement shall be commenced only in a court of the Commonwealth
      of Massachusetts (or, if appropriate, a federal court located within
      Massachusetts), and the Company and the Employee each consents to the
      jurisdiction of such a court.

THE EMPLOYEE ACKNOWLEDGES THAT HE/SHE HAS CAREFULLY READ THIS AGREEMENT AND
UNDERSTANDS AND AGREES TO ALL OF THE PROVISIONS IN THIS AGREEMENT.

WITNESS:

VARIAGENICS, INC.

Date:       12/23/98                      By:  /s/ Fred D. Ledley, M.D.
      -----------------------------            ------------------------
                                               Fred D. Ledley, M.D.
                                               President & CEO

By Employee:                              By:  /s/ Richard P. Shea
                                               ------------------------
                                               Richard P. Shea
Date:       12/23/98
      -------------------
<PAGE>

                                    EXHIBIT 1

                     Invention and Non-Disclosure Agreement

                                Other Agreements

Pursuant to section 3 of this Agreement, the following is a list of pertinent
agreements between the Employee and previous employers or other parties:

                  |_|   None
                  |X|   As shown below

      Consulting agreement dated October 24, 1998 with Pavonis, Inc.
      Consulting agreement dated October 24, 1998 with Pavonis, Inc.

By:  VARIAGENICS, INC.:                   By:  Employee:

/s/ Fred D Ledley, M.D.                   /s/ Richard P. Shea
------------------------------            ------------------------------
                                          Richard P. Shea

Dated:     12/23/98                       Dated:     12/23/98
      ------------------------                  ------------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00005-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00005-of-00352.parquet"}]]