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                                                                Exhibit 10.58


                              EMPLOYMENT AGREEMENT

     EMPLOYMENT AGREEMENT ("Agreement") made and entered into effective as of
January 1, 2004 (the "Effective Date"), by and between GENAISSANCE
PHARMACEUTICALS, INC. (the "Corporation"), a Delaware corporation with its
principal office at 5 Science Park, New Haven, Connecticut, 06511, and GERALD F.
VOVIS, PH.D. ("Executive"), an individual who resides at 29 North Pond Road,
Cheshire, Connecticut 06410.

     WHEREAS, the Corporation and Executive desire to enter into this Agreement
to set forth the terms and conditions of their employment relationship,
commencing as of the Effective Date;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties agree as follows:

     1.   EMPLOYMENT. The Corporation shall employ Executive in the capacity of
Executive Vice President and Chief Technology Officer ("EVP") of the Corporation
during the term of this Agreement, and Executive hereby accepts such employment,
on the terms and conditions hereinafter set forth. Executive represents that his
employment by the Corporation pursuant to this Agreement does not violate any
agreement, covenant or obligation to which he is a party or by which he is
bound.

     2.   DUTIES. During the term of this Agreement, Executive shall perform all
duties, consistent with his position as EVP in order to help develop and advance
the Corporation's business strategy, corporate relations, and genomics
technology and related business efforts, assigned or delegated to him by the
Chief Executive Officer of the Corporation or his delegate (the "CEO"), and
normally associated with the position of EVP, including, without limitation, by
assisting in the evaluation of opportunities and in making recommendations on
acquisitions and mergers to the CEO, by reviewing publicity and SEC filings,
representing the Corporation at business meetings and presenting to analysts, by
managing, as necessary to support the Corporation's operations, the
Corporation's pharmacogenomics support services business as the CEO shall, from
time to time, request Executive to manage and by addressing strategic and
tactical business decisions of the Corporation related to genomics and
pharmacogenomics with other senior managers and advisors to the Corporation. He
shall devote all of his full business time and best efforts to the advancement
of the interests and business of the Corporation, except that he shall be
permitted from time to time to fulfill his responsibilities as a member of the
Board of Trustees of Knox College, so long as such responsibilities do not
interfere with his performance of his duties to the Corporation.

     3.   TERM. The term of this Agreement shall begin on the Effective Date,
and shall expire on the fourth anniversary of the Effective Date, unless earlier
terminated as provided in this Agreement (the "Initial Term"). Upon expiration
of the Initial Term and any subsequent term or extension thereof, this Agreement
shall automatically be extended for an additional term

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of one (1) year, unless Executive or the Corporation elect to terminate this
Agreement in accordance with the provisions of Section 12 of this Agreement (the
"Initial Term", together with any subsequent terms or extensions, until
termination or expiration in accordance with the provisions of this Agreement,
shall be referred to herein as the "Employment Term"). If Executive continues in
the employ of the Corporation after the end of any Employment Term, then
Executive's continued employment by the Corporation shall, notwithstanding
anything to the contrary expressed or implied herein, be terminable by the
Corporation at will.

     4.   COMPENSATION. As compensation for any and all services to be rendered
by Executive to the Corporation pursuant to this Agreement, the Corporation
shall pay Executive and provide Executive with the following compensation and
benefits, which Executive agrees to accept in full satisfaction for his
services:

          a.   BASE SALARY. The Corporation shall pay Executive a Base Salary,
     payable in equal installments at such payment intervals as are the usual
     payroll practices of the Corporation, at an annual rate of $230,000, less
     such deductions or amounts to be withheld as shall be required by
     applicable law or as may be allowed at the request of Executive (the "Base
     Salary"). The Base Salary shall be reviewed annually by the Board after the
     end of each fiscal year of the Corporation and shall be increased, but not
     decreased by such amount, if any, as the CEO, in his sole discretion, shall
     determine and the Board, in its sole discretion, shall approve. Any such
     increase of Base Salary shall be made effective as of January 1 of the
     fiscal year to which it applies.

          b.   BONUS. Provided Executive first meets the Corporation's
     expectations for his performance during the Employment Term and remains
     employed on the date of payment, Executive shall be eligible for a
     discretionary bonus (a "Discretionary Bonus") in an amount, if any,
     determined by the Board in its sole discretion based upon Executive's
     achievements in meeting his performance goals and those of the Corporation
     for its most recently ended fiscal year. Goals shall be established in the
     first quarter of each fiscal year after the commencement of the Employment
     Term. Each Discretionary Bonus may be payable in cash, stock options,
     and/or restricted stock upon such terms and conditions as determined by the
     CEO. The Corporation shall pay any Discretionary Bonus as soon as
     reasonably possible after the close of its books at the end of the fiscal
     year. As any bonus paid to Executive is discretionary, the payment of any
     bonus in respect of a particular fiscal year must not be construed as
     requiring the payment of a bonus in respect of any other fiscal year.

          c.   BENEFITS.

               (i)    Executive shall be entitled to participate, to the extent
          he is eligible, in all group insurance programs, health, medical,
          dental, and disability plans and other employee benefit plans
          (including, without limitation, the Corporation's 401(k) plan), which
          the Corporation may hereafter in its sole and absolute discretion make
          available generally to members of its senior management team (other
          than any incentive compensation or equity ownership plan), but the

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          Corporation shall not be required to establish or maintain any such
          program or plan.

               (ii)   Executive shall be entitled to four (4) weeks paid
          vacation during each calendar year, in accordance with the
          Corporation's vacation policies. Such vacation may be taken at such
          time or times as is reasonably consistent with the Corporation's
          vacation policies and the performance by Executive of his duties and
          responsibilities under this Agreement. Up to one week of unused
          vacation time in one year may be carried over and used in the
          subsequent year.

               (iii)  Executive shall be entitled to participate in the
          Corporation's 2000 Amended and Restated Equity Incentive Plan (the
          "Plan") and the Corporation's Employee Stock Purchase Plan, or any
          successor plans. In addition, Executive shall be eligible to
          participate in the Plan with respect to his future performance as a
          senior executive of the Corporation. Executive understands and agrees
          that any stock rights granted to Executive shall be subject to the
          provisions of the Plan and any separate written agreements embodying
          the grant of the rights that are required by the Plan. The rights
          shall be set forth in a separate agreement embodying the grant of the
          rights which shall be otherwise in the form stipulated in the Plan.

               (iv)   The Corporation shall purchase and throughout the
          Employment Term pay the premiums for a $1,000,000 policy of term life
          insurance insuring the life of Executive (subject to his meeting the
          suitability requirements of the insurer). Executive shall be the owner
          of such policy and entitled to all of the rights of ownership
          including designation of the beneficiary thereof.

               (v)    Subject to reasonable guidelines adopted by the Board,
          throughout the Employment Term, the Corporation shall pay the costs of
          dues for Executive's membership in professional organizations whose
          activities are reasonably related to the business of the Corporation.

               (vi)   The Corporation shall provide Executive with a policy of
          long-term disability insurance with reasonable coverages, which shall
          include the payment of benefits equal to at least 60% of Executive's
          Base Salary during the disability coverage period, and the Corporation
          shall pay the premiums or a portion thereof (as specified hereafter)
          for such disability insurance policy up to the cost charged by the
          insurer to insure a healthy male non-smoker of Executive's age.

          d.   TAXES. All compensation and benefits are subject to applicable
     withholding taxes, federal, state, and local, and any other proper
     deductions.

          e.   BENEFIT PLANS. Executive understands that the Corporation may
     amend, change, or cancel its employment policies and benefit plans that are
     applicable to all

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     employees of the Corporation and members of the senior management team at
     any time as allowed by law or by any applicable plan documents.

     5.   BUSINESS EXPENSES. The Corporation shall pay, or reimburse Executive
for, the reasonable and necessary business expenses of Executive incurred in the
performance of his duties hereunder, provided Executive provides timely and
reasonable documentation thereof in accordance with the rules and regulations of
the Corporation relating thereto.

     6.   COMPLIANCE WITH POLICIES. Executive acknowledges and agrees that,
except as set forth in this Agreement, compliance with the Corporation's
generally applicable policies, practices and procedures is a term and condition
of his employment under this Agreement.

     7.   INVENTIONS AND IMPROVEMENTS. Executive acknowledges, covenants and
agrees that the Corporation shall be the sole owner of all the fruits and
proceeds of Executive's services to the Corporation, including but not limited
to all writings, inventions, discoveries, designs, systems, processes, software
or other improvements relating to the business or products of the Corporation,
whether or not patentable, registerable, or copyrightable, which Executive may,
alone or with others, conceive, create, develop, produce or make during or as a
result of his employment with the Corporation (collectively, the "Invention"),
free and clear of any claims by Executive of any kind or character whatsoever
other than Executive's rights to compensation under this Agreement. Executive
agrees that he shall disclose each of the Inventions promptly and completely to
the Corporation, and shall, at the request of the Board, execute such
assignments, certificates or other instruments as the Board or the Corporation
from time to time deem necessary or desirable to evidence, establish, maintain,
perfect, protect, enforce or defend the Corporation's right, title and interest
in or to any or all of the Inventions. Executive agrees that he is bound by the
terms of a certain Employee Agreement on Ideas, Inventions, and Confidential
Information, dated April 19, 1999 (the "Inventions Agreement"), which shall
continue in full force and effect according to its terms and nothing in this
Agreement shall be interpreted or construed as modifying the Inventions
Agreement. To the extent that there is any conflict between the provisions of
this Section and the provisions of the Inventions Agreement, the provisions of
the Inventions Agreement shall govern.

     8.   NON-DISCLOSURE OF CONFIDENTIAL INFORMATION.

          a.   Executive acknowledges that, in and as a result of his employment
     by the Corporation, he will be making use of, acquiring and/or adding to
     the Corporation's Confidential Information (as hereinafter defined). As a
     material inducement to the Corporation to employ Executive and to pay
     Executive the compensation and benefits set forth in this Agreement,
     Executive covenants and agrees that he shall not, at any time during or
     following the term of his employment with the Corporation, directly or
     indirectly divulge or disclose for any purposes whatsoever, any
     Confidential Information that has been obtained by, or disclosed to, him as
     a result of his employment with the Corporation. For purposes of this
     Agreement, "Confidential Information" means, collectively, all confidential
     matters and materials of the Corporation, including without limitation, (i)
     the Corporation's proprietary information, inventions, trade secrets,
     knowledge, data, know-how, intellectual property, systems, procedures,
     manuals, pricing

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     policies, operational methods and information relating to the Corporation's
     products, processes, formulae, business plans, marketing plans and
     strategies, pricing strategies, customer lists, and all other subject
     matters pertaining to the business and/or financial affairs of the
     Corporation; (ii) the Corporation's information regarding plans and
     strategies for research, development, new products, future business plans,
     budgets and unpublished financial statements, licenses, prices and costs;
     (iii) information regarding the skills and compensation of other employees
     of the Corporation; and (iv) information disclosed in confidence to the
     Corporation by a third party with a duty on the Corporation to maintain the
     confidentiality of such information. The term "Confidential Information"
     shall not include any information that (x) has been made available
     generally to the public either by the Corporation or by a third party with
     the Corporation's consent, unless such information became available as a
     result of any action by Executive in violation of this Agreement, any other
     agreement, or his obligations under law, or (y) has been made available as
     a result of a final award, order, or ruling by an arbitration tribunal or a
     court of competent jurisdiction that has determined that such Confidential
     Information may be disclosed.

          b.   If Executive is required by a court, arbitration tribunal, or
     governmental agency (by oral questions, interrogatories, requests for
     information or documents, subpoena, civil investigation demand or similar
     process) to disclose any Confidential Information, Executive may disclose
     such Information to such court, tribunal, or agency without liability
     hereunder, PROVIDED, THAT Executive first provides the Corporation with
     notice of any such requirement(s) as promptly as practicable, but in any
     case with sufficient timeliness to enable the Corporation to seek an
     appropriate protective order and/or waive its compliance with the relevant
     provisions of this Agreement.

     9.   COVENANTS AGAINST COMPETITION.

          a.   NON-SOLICITATION OF EMPLOYEES. While employed by the Corporation
     and for a period of six (6) months, followed by a second period of six (6)
     months, for a total period of twelve (12) months, from the date of
     termination of Executive's Employment Term with the Corporation for any
     reason, Executive shall not directly or indirectly solicit, induce or
     encourage any of the Corporation's employees to terminate their employment
     with the Corporation or to accept employment with any competitor, supplier,
     client, agent or broker of the Corporation, nor shall Executive cooperate
     with any others in doing or attempting to do so. As used in this Section
     9a, the term "solicit, induce or encourage" includes, but is not limited
     to, (i) initiating communications with any employee of the Corporation
     relating to possible employment or independent contractor relationship,
     (ii) offering bonuses or additional compensation to encourage any employee
     of the Corporation to terminate his or her employment with the Corporation
     and accept employment with a competitor, supplier, client, agent or broker
     of the Corporation, or (iii) referring any employee of the Corporation to
     recruiters, personnel or agents employed by competitors, suppliers,
     clients, agents or brokers of the Corporation. Notwithstanding the
     foregoing, the term "solicit, induce or encourage", as used in this Section
     9a, specifically excludes any action by the Executive related to any of the
     Corporation's employees where

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     it is in the Corporation's best interest to terminate any such employees as
     in the case of a planned reduction in force by the Corporation.

          b.   NON-COMPETE. While Executive is employed by the Corporation and
     for a period of six (6) months, followed by a second period of six (6)
     months, for a total period of twelve (12) months from the date of
     termination of Executive's Employment Term for any reason, Executive shall
     not directly or indirectly, as a principal, agent, contractor, employee,
     employer, partner, shareholder, proprietor, investor, member, director,
     officer, or consultant, or in any other capacity, engage in or perform any
     managerial or executive services (a) for any corporation, partnership,
     individual or entity which is engaged in a business competitive with the
     Corporation or affiliate of the Corporation or (b) for any customer of the
     Corporation or affiliate of the Corporation.

          c.   For the purposes of this Agreement:

               (i)    The term "engaged in a business competitive with the
          Corporation" means directly or indirectly engaging in the business of
          pharmacogenomics or pharmacogenetics or in the same or any similar
          business as the Corporation or any of its affiliates in any manner
          whatsoever within any geographic area in which the Corporation's
          products or services are offered or distributed;

               (ii)   The term "affiliate" means any legal entity that directly
          or indirectly through one or more intermediaries controls, is
          controlled by, or is under common control with the Corporation; and

               (iii)  The term "customer" means any business, company, person,
          and any other entity to whom the Corporation or any of its affiliates
          has provided any product or service, whether or not for compensation,
          within a period of two (2) years prior to the time Executive ceases to
          be employed by the Corporation.

          d.   EXCLUSION FOR INVESTMENTS. None of the provisions of this Section
     9 shall prohibit Executive from investing in securities (i) listed on a
     national securities exchange or actively traded over-the-counter so long as
     such investments are not greater than five percent (5%) of the outstanding
     securities of any issuer of the same class or issue, or (ii) of entities
     engaged in a business competitive with the Corporation so long as any such
     entity was not engaged in a business competitive with the Corporation at
     the time Executive made such investment.

     10.  REASONABLENESS OF RESTRICTIONS.

          a.   Executive has carefully read and considered the provisions of
     Section 8 and Section 9, and, having done so, agrees that:

               (i)    The restrictions set forth in Section 8 and Section 9,
          including but not limited to the character, duration, and geographical
          area of restriction, are fair and reasonable and are reasonably
          required for the protection of the good will and

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          other legitimate business interests of the Corporation and its
          affiliates, officers, directors, shareholders, and other employees;

               (ii)   Executive has received, or is entitled to receive pursuant
          to the terms of this Agreement, adequate consideration for such
          obligations; and

               (iii)  Such obligations do not prevent Executive from earning a
          livelihood.

          b.   If, notwithstanding the foregoing, any of the provisions of
     Section 8 or Section 9 shall be held to be invalid or unenforceable, the
     remaining provisions thereof shall nevertheless continue to be valid and
     enforceable as though the invalid and unenforceable parts had not been
     included therein. If any provision of Section 8 or Section 9 is determined
     by a court of competent jurisdiction that the character, duration,
     geographical scope, or related aspects are unreasonable in light of the
     circumstances as they then exist, then it is the intention of the parties
     that Section 8 and/or Section 9 shall be construed by the court in such a
     manner as to impose only those restrictions on the conduct of Executive
     that are reasonable in light of the circumstances as they then exist and as
     are necessary to assure the Corporation of the intended benefit of this
     Agreement and such restrictions, as so modified, shall become and
     thereafter be the maximum restriction in such regard, and the restriction
     shall remain enforceable to the fullest extent deemed reasonable by such
     court.

     11.  REMEDIES FOR BREACH OF EXECUTIVE'S COVENANTS OF NON-DISCLOSURE AND
NON-COMPETITION. Executive recognizes and agrees that the Corporation's remedy
at law for any breach of Section 8 or Section 9 would be inadequate as such a
breach would cause irreparable harm to the Corporation, and he agrees that, for
any actual or threatened breach of such provisions, the Corporation shall, in
addition to such other remedies as may be available to it at law or in equity,
be entitled to injunctive relief and to enforce its rights by an action for
specific performance. All of the Corporation's remedies for any breach of this
Agreement shall be cumulative and the pursuit of any one remedy shall not
exclude the Corporation's pursuit of any other remedies.

     12.  TERMINATION AND SEVERANCE.

          a.   DEATH. In the event that Executive dies during the Employment
     Term, this Agreement shall terminate automatically upon his death, upon
     which event Executive's legal representatives shall be entitled to receive,
     and the Corporation shall pay or cause to be paid to Executive's legal
     representatives, any Base Salary and other compensation or benefits accrued
     but as yet unpaid on the date of Executive's death.

          b.   INCAPACITY OR DISABILITY. If during the Employment Term,
     Executive is prevented from performing the duties or fulfilling
     responsibilities of his employment under this Agreement by reason of any
     incapacity or disability for a continuous period of six (6) months, as
     determined by an independent qualified physician selected by the
     Corporation and reasonably acceptable to Executive (or his representative),
     then the

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     Corporation may terminate Executive's employment hereunder, but Executive
     shall continue to be eligible to receive any benefits to which he may be
     entitled under the terms of any long-term disability plan or insurance
     policy maintained by the Corporation for its employees generally or for
     Executive specifically. In the event of such incapacity or disability, the
     Corporation shall continue to pay full compensation to Executive in
     accordance with the terms of this Agreement until the date of such
     termination.

          c.   BY CORPORATION FOR CAUSE. The Corporation may, upon written
     notice to Executive, terminate Executive's employment hereunder for Cause
     (as defined hereafter); provided that the Corporation shall first provide
     Executive with an opportunity to be heard by the Board on any proposed
     termination for Cause by the Board. For purposes of this Agreement, the
     term "Cause" shall mean (i) Executive's material breach of this Agreement
     if the Corporation has notified Executive of such breach and he has not
     cured such breach within 15 days of having received such notice; (ii)
     Executive's material failure to adhere to any policy of the Corporation
     generally applicable to employees of the Corporation if Executive has been
     given a reasonable opportunity to comply with such policy or cure his
     failure to comply; (iii) Executive's appropriation (or attempted
     appropriation) of a business opportunity of the Corporation, including
     attempting to secure or securing any personal profit in connection with any
     transaction entered into on behalf of the Corporation; (iv) Executive's
     misappropriation (or attempted misappropriation) of any of the
     Corporation's funds or property; (v) Executive's conviction of, or the
     entering of a guilty plea or plea of no contest with respect to, a felony,
     the equivalent thereof, or of a lesser crime having as its predicate
     element fraud, dishonesty or misappropriation of property of the
     Corporation; (vi) Executive's willful misconduct or insubordination; (vii)
     Executive's physical or mental disability or other inability to perform the
     essential functions of his position for a consecutive six (6) month period,
     with or without reasonable accommodation, as determined by an independent
     qualified physician selected by the Corporation and reasonably acceptable
     to Executive (or his representative), if Executive is not eligible for
     benefits under the terms of any long-term disability policy or insurance
     policy maintained by the Corporation for its employees generally or for
     Executive specifically; (viii) Executive's engaging in bad faith or gross
     negligence in the performance of his duties under this Agreement as
     determined in good faith by the Board; or (ix) any other conduct of
     Executive sufficiently detrimental to the Corporation so as to warrant
     immediate termination of Executive's employment with the Corporation.

          In the event of termination for Cause of Executive's employment,
     Executive's right to receive compensation and other benefits hereunder
     (other than any Base Salary and any vacation accrued but as yet unpaid on
     the effective date of such termination) shall terminate on the effective
     date of such termination, and Executive shall not be entitled to any
     severance payments or other benefits.

          d.   TERMINATION BY THE CORPORATION WITHOUT CAUSE. The Corporation may
     elect to terminate Executive's employment at any time without Cause upon
     written notice to Executive. In the event of such termination without
     Cause, Executive shall be entitled to a severance payment in an amount
     equal to 125% of Executive's Base Salary as of the

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     date of termination, such payment to be made in equal installments over a
     twelve (12) month period on the Corporation's usual pay periods.

          e.   NONRENEWAL OF AGREEMENT. The Corporation may elect to not renew
     or extend this Agreement at any time without Cause upon written notice to
     Executive not later than thirty (30) days prior to the end of any Initial
     Term or any extended Employment Term. In the event of a nonrenewal or
     non-extension pursuant to this Section 12e, Executive's rights to receive
     compensation and other benefits (other than any Base Salary and vacation
     accrued but as yet unpaid on the effective date of such termination) shall
     terminate at the expiration of the Initial Term or Employment Term. In the
     event of such termination, Executive shall be entitled to a severance
     payment following the end of such Initial Term or Employment Term in an
     amount equal to 125% of Executive's Base Salary as of the date of
     termination, such payment to be made in equal installments over a twelve
     (12) month period on the Corporation's usual pay periods.

          f.   BY EXECUTIVE FOR CERTAIN REASONS. Executive may, at his option,
     upon at least thirty (30) days written notice to the Corporation, terminate
     his employment hereunder, if the Corporation, without Executive's express
     written consent, (i) removes him as an officer of the Corporation, (ii)
     demotes him from EVP, (iii) assigns him duties materially inconsistent with
     the position and/or duties described in Sections 1 or 2, (iv) materially
     diminishes his responsibilities described in Sections 1 or 2, (v) breaches
     any material obligations to Executive under this Agreement, or (vi) in
     connection with a Change of Control (as defined hereafter), the Corporation
     requires Executive to relocate his office to a location that is more than
     thirty-five (35) miles from its existing location at 5 Science Park, New
     Haven, Connecticut. Upon any termination by Executive under this Paragraph
     the Corporation shall be obligated to pay Executive the severance payments
     specified in Section 12d.

          g.   BY EXECUTIVE FOLLOWING CHANGE OF CONTROL. Executive may, at his
     option, upon thirty (30) days written notice to the Corporation, terminate
     his employment hereunder for Good Reason (as hereinafter defined) following
     a Change of Control of the Corporation. Upon any termination by Executive
     under this Paragraph, the Corporation shall be obligated to pay Executive a
     severance payment in an amount equal to 150% of Executive's Base Salary as
     of the date of termination for an eighteen (18) month period, payable in
     equal installments over such eighteen (18) month period on the
     Corporation's usual pay periods. Termination by Executive of his employment
     pursuant to this paragraph shall not be deemed a voluntary termination by
     Executive pursuant to Section 12i below.

          h.   GOOD REASON DEFINED. For purposes of this Agreement, the term
     "Good Reason" means, during the thirty (30) day period prior to or the
     twelve (12) month period following a Change of Control, without Executive's
     express written consent, the occurrence of any of the following
     circumstances:

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               (i)    the assignment to Executive of any duties inconsistent
          (except in the nature of a promotion) with the position in the
          Corporation that he held immediately prior to the Change of Control or
          substantial adverse alteration in the nature or status of his position
          or responsibilities or the conditions of his employment from those in
          effect immediately prior to the Change of Control;

               (ii)   a reduction, other than a de minimis reduction, by the
          Corporation in Executive's annual Base Salary as in effect on the date
          hereof, as the same may be increased from time to time;

               (iii)  the failure by the Corporation to continue in effect any
          material compensation or benefit plan in which Executive participates
          immediately prior to the Change of Control unless an equitable
          arrangement (embodied in an ongoing substitute or alternative plan)
          has been made with respect to such plan, or the failure by the
          Corporation to continue Executive's participation therein (or in such
          substitute or alternative plan) on a basis not materially less
          favorable, both in terms of the amount of benefits provided and the
          level of his participation relative to other participants, than
          existed immediately prior to the Change of Control.

          i.   VOLUNTARY TERMINATION BY EXECUTIVE. Executive may, at his option,
     upon thirty (30) days prior written notice to the Corporation, terminate
     his employment hereunder. In the event of a voluntary termination of his
     employment by the Executive pursuant to this Paragraph, Executive's rights
     to receive compensation and other benefits (other than any Base Salary and
     vacation accrued but as yet unpaid on the effective date of such
     termination) shall terminate on the effective date of such termination, and
     Executive shall not be entitled to any severance payments or other
     benefits.

          j.   ELIGIBILITY FOR SEVERANCE; REQUIREMENT OF RELEASE. Except as
     provided in Sections 12d, 12e, 12f and 12g, Executive shall not be eligible
     for or entitled to any severance payments in the event of termination of
     his employment hereunder. No severance shall be paid under this Agreement
     unless Executive first executes and agrees to be bound by a release of all
     claims (other than claims that Executive may then or thereafter have in
     respect of Base Salary, reimbursement of reasonable expenses incurred
     within the three (3) month period prior to the date of his termination or
     other expenses due to him under this Agreement), on a form provided by the
     Corporation, which releases any and all claims that Executive has or might
     have against the Corporation and which contains terms customary in such
     agreements.

          k.   RESIGNATION. In the event of termination of his employment other
     than for death, Executive shall be deemed to have resigned from all
     positions held in the Corporation, including without limitation any
     position as a director, officer, agent, trustee, or consultant of the
     Corporation or any affiliate of the Corporation. Upon request of the
     Corporation, Executive shall promptly sign and deliver to the Corporation
     any and all documents reflecting such resignations as of the date of
     termination of his employment.

     13.  VESTING UPON CHANGE IN CONTROL; EXERCISE.

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          a.   Any stock grant or options granted to Executive by the
     Corporation shall accelerate and immediately vest as of the date of any
     termination or expiration of Executive's employment with the Corporation
     (or its successor), which occurs at the time of, or within the six (6)
     month period after, a Change of Control. "Change of Control" means the
     occurrence of the following events: if (a) any "person," as such term is
     used in Sections 13d and 14e of the Securities and Exchange Act of 1934, as
     amended (the "Exchange Act") (other than the Corporation, any trustee or
     other fiduciary holding securities under an employee benefit plan of the
     Corporation, or any corporation owned directly or indirectly by the
     stockholders of the Corporation in substantially the same proportion as
     their ownership of stock in the Corporation) is or becomes the "Beneficial
     Owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
     indirectly, of securities of the Corporation representing 50% or more of
     the combined voting power of the Corporation's then outstanding securities
     (other than as a result of acquisitions of such securities from the
     Corporation); (b) individuals who, as of the date hereof, constitute the
     Board of Directors of the Corporation (the "Incumbent Board") cease for any
     reason to constitute at least a majority of the Board, provided that any
     person becoming a director after the date hereof whose election, or
     nomination for election by the Corporation's stockholders, was approved by
     a majority of the directors then comprising the Incumbent Board (other than
     an election or nomination of an individual whose initial assumption of
     office is in connection with an actual or threatened election contest
     relating to the election of the directors of the Corporation) shall be, for
     purposes of this Agreement, considered to be a member of the Incumbent
     Board; (c) the stockholders of the Corporation approve a merger or
     consolidation of the Corporation with any other corporation, other than (i)
     a merger or consolidation that would result in the voting securities of the
     Corporation outstanding immediately prior thereto continuing to represent
     (either by remaining outstanding or by being converted into voting
     securities of the surviving entity) more than 50% of the combined voting
     power of the voting securities of the Corporation or such surviving entity
     outstanding immediately after such merger or consolidation or (ii) a merger
     or consolidation effected to implement a recapitalization of the
     Corporation (or similar transaction) in which no "person" (as defined
     above, acquires more than 20% of the combined voting power of the
     Corporation's then outstanding securities; or (d) the stockholders of the
     Corporation approve a plan of complete liquidation of the Corporation or an
     agreement for the sale or disposition by the Corporation of all or
     substantially all of the Corporation's assets. Notwithstanding the
     foregoing, if the Incumbent Board specifically determines in good faith
     that any transaction does not constitute a Change of Control for purposes
     of this Agreement, such determination shall be conclusive and binding.

          b.   In the event Executive's stock grants and/or options accelerate
pursuant to this Agreement, Executive shall be permitted to exercise any and all
vested options which he holds for a period of up to twelve (12) months following
the date of termination or expiration of his employment to the extent permitted
by applicable law.

     14.  PAYMENT OR BENEFIT IN CONNECTION WITH CHANGE OF CONTROL.

                                     - 11 -
<Page>

          a.   Notwithstanding any other provision of this Agreement, in the
event that any payment or benefit received or to be received by the Executive
(i) is deemed to be in connection with a Change in Control (whether payable
pursuant to the terms of this Agreement or any other plan, arrangement or
agreement with the Corporation, its successors, any person whose actions result
in a Change in Control or any corporation ("Affiliates") affiliated (or which,
as a result of the completion of the transactions causing a Change in Control
will become affiliated) with the Corporation within the meaning of Section 1504
of the Internal Revenue Code of 1986, as amended (the "Code") (collectively with
the payments and benefits pursuant to this Agreement if deemed to be paid
pursuant to a Change in Control, "Total Payments")) and (ii) it is determined by
the Corporation's independent certified accounting firm (the "Tax Advisor") that
the Total Payments exceed 2.99 times the base amount (as such term is defined
under Section 280G(b)(3) of the Code) but equal less than 4 times such base
amount and that an excise tax is payable by Executive under Section 4999 of the
Code, then the amount of payments to the Executive shall be reduced so that the
payments do not exceed the limits then set forth in Section 280G of the Code.

          b.   Notwithstanding any other provisions of this Agreement or the
provisions of subsection 14a above, in the event that the Tax Advisor determines
that the Total Payments would be subject (in whole or part), to an excise tax
pursuant to Section 4999 of the Code (such tax hereinafter referred to as the
"Excise Tax") and the Tax Advisor determines that the Total Payments equal or
exceed four (4) times the base amount (as such term is defined under Section
280G(b)(3) of the Code), then the Total Payments shall be grossed up to the
extent necessary to reflect any Excise Taxes due by Executive (and the income
taxes attributable to the additional payment) so that the Executive will be
entitled to a net amount equal to the Total Payments (the "Grossed-Up Payment").
For purposes of determining whether and the extent to which the Total Payments
will be subject to the Excise Tax, (i) no portion of the Total Payments the
receipt or enjoyment of which Executive shall have effectively waived in writing
prior to the date of this termination of employment shall be taken into account,
(ii) no portion of the Total Payments shall be taken into account which in the
opinion of Tax Advisor does not constitute a "parachute payment" within the
meaning of Section 280G(b)(2) of the Code, (including by reason of Section
280(b)(4)(A) of the Code) and, in calculating the Excise Tax, no portion of such
Total Payment shall be taken into account which constitutes reasonable
compensation for services actually rendered, within the meaning of Section
280G(b)(4)(B) of the Code, in excess of the base amount as defined in Section
280G(b)(3) of the Code allocable to such reasonable compensation, and (iii) the
value of any non-cash benefit or any deferred payment or benefit included in the
Total Payments shall be determined by Corporation in accordance with the
principles of Sections 280G(d)(3) and (4) of the Code. Prior to the thirtieth
day following the date of Executive's termination of employment, Corporation
shall provide Executive with its calculation of the amounts referred to in this
Section and such supporting materials as are reasonably necessary for Executive
to evaluate Corporation's calculations but the Tax Advisor's calculations shall
be used for purposes of any payments pursuant to this Section.

          c.   If the Corporation's Tax Advisor determines that the Total
Payments received or to be received by Executive fall under subsection 14a above
and upon audit by the Internal Revenue Service (the "IRS"), the IRS determines
that an Excise Tax is due and payable due to the amount of the Total Payments
received by Executive, notwithstanding the reductions

                                     - 12 -
<Page>

in payments under subsection 14a, then in lieu of any further reduction the
Corporation agrees to make a Grossed-Up Payment calculated in the same manner as
provided in subsection 14b above.

          d.   In the event of any IRS audit concerning the Total Payments
payable or paid to Executive, the Corporation may in its sole discretion choose
to respond to the audit. If the Corporation chooses not to respond, then it
shall be the sole responsibility of Executive to respond to the audit. Each
party shall reasonably cooperate with the other in any such proceedings.

     15.  WAIVER. A party's failure to insist on compliance or enforcement of
any provision of this Agreement shall not affect the validity or enforceability
or constitute a waiver of future enforcement of that provision or of any other
provision of this Agreement by that party or any other party.

     16.  GOVERNING LAW. This Agreement shall in all respects be subject to, and
governed by, the laws of the State of Connecticut without reference to its
conflict of laws. The parties acknowledge that each of them will act in good
faith and deal fairly with respect to their respective rights and obligations
under this Agreement.

     17.  SEVERABILITY. The invalidity or unenforceability of any provision in
the Agreement shall not in any way affect the validity or enforceability of any
other provision and this Agreement shall be construed in all respects as if such
invalid or unenforceable provision had never been in the Agreement.

     18.  NOTICE. Any and all notices required or permitted herein shall be in
writing and shall be deemed to have been duly given (a) when delivered if
delivered personally, (b) on the fifth day following the date of deposit in the
United States mail if sent first class, postage prepaid, or by certified mail,
or (c) one day after delivery to a nationally recognized overnight courier
service. The parties' respective addresses for such notices shall be those set
forth below, or such other address or addresses as either party may hereafter
designate in writing to the other.

     If to the Corporation:  Genaissance Pharmaceuticals, Inc.
                             Five Science Park, Suite 2103
                             New Haven, CT 06511-1966
                             Attention: Kevin Rakin
                             Facsimile No.: (203) 492-4473

     With a copy to:         Robinson & Cole LLP
                             280 Trumbull Street
                             Hartford, CT 06103-3597
                             Attention: Felicia DeDominicis, Esq.
                             Facsimile No.: (860) 275-8299

     If to Employee:         Gerald F. Vovis, Ph.D.
                             29 North Pond Road

                                     - 13 -
<Page>

                             Cheshire, CT 06410

     With a copy to:         Minz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
                             One Financial Center
                             Boston, MA 02111
                             Attention: Stan Twarog, Esq.

     19.  ASSIGNMENT. This Agreement shall inure to the benefit of, and shall be
binding upon, the parties hereto and their respective successors, assigns,
heirs, and legal representatives, including any entity with which the
Corporation may merge or consolidate or to which all or substantially all of its
assets may be transferred. The duties and covenants of Executive under this
Agreement, being personal, may not be delegated.

     20.  AMENDMENTS. This Agreement may be amended at any time by mutual
consent of the parties hereto, with any such amendment to be invalid unless in
writing and signed by the Corporation and Executive and expressly referring to
this Agreement.

     21.  ENTIRE AGREEMENT. This Agreement contains the entire agreement and
understanding by and between Executive and the Corporation with respect to the
employment of Executive and supersedes all existing agreements between the
Corporation and Executive with respect to such subject matter. No
representations, promises, agreements, or understandings, written or oral,
relating to the employment of Executive by the Corporation, or any of its
officers, directors, employees, or agents, not contained herein shall be of any
force or effect, provided that, Sections 5, 6, 7, 8, and 9 shall be supplemental
to any other agreement of Executive with the Corporation related to the matters
identified therein.

     22.  NO UNDUE INFLUENCE; CONSTRUCTION. This Agreement is executed
voluntarily and without any duress or undue influence. Executive acknowledges
that he has read this Agreement and executed it with his full and free consent.
No provision of this Agreement shall be construed against any party by virtue of
the fact that such party or its counsel drafted such provision or the entirety
of this Agreement.

     23.  REFERENCES TO GENDER AND NUMBER TERMS. In construing this Agreement,
feminine or neuter pronouns shall be substituted for those masculine in form and
vice versa, and plural terms shall be substituted for singular and singular for
plural in any place in which the context so requires.

     24.  COUNTERPARTS; HEADINGS; SECTIONS. This Agreement may be executed in
multiple counterparts, each of which shall be considered to have the force and
effect of any original but all of which taken together shall constitute but one
and the same instrument. The various headings in this Agreement are inserted for
convenience only and are not part of the Agreement. All references to "Sections"
and "Paragraphs" in this Agreement refer to the various corresponding sections
and paragraphs of this Agreement.

     25.  SURVIVAL. The covenants and agreements contained in Sections 5 through
9 shall survive any termination of Executive's employment with the Corporation.

                                     - 14 -
<Page>

     26.  ARBITRATION. Executive and the Corporation shall submit any disputes
arising under this Agreement to an arbitration panel conducting a binding
arbitration in Hartford, Connecticut or at such other location as may be
agreeable to the parties, in accordance with the National Rules for the
Resolution of Employment Disputes of the American Arbitration Association in
effect on the date of such arbitration (the "Rules"), and judgment upon the
award rendered by the arbitrator or arbitrators may be entered in any court
having jurisdiction thereof; PROVIDED, HOWEVER, that nothing herein shall impair
the Corporation's right to seek equitable relief for any breach or threatened
breach of Section 8 or Section 9. The award of the arbitrators shall be final
and shall be the sole and exclusive remedy between the parties regarding any
claims, counterclaims, issues or accountings presented to the arbitration panel.
The parties hereto further agree that the arbitration panel shall consist of one
(1) person mutually acceptable to the Corporation and Executive, PROVIDED that
if the parties cannot agree on an arbitrator within thirty (30) days of filing a
notice of arbitration, the arbitrator shall be selected by the manager of the
principal office of the American Arbitration Association serving Hartford County
in the State of Connecticut. Each party will pay for the fees and expenses of
its own attorneys, experts, witnesses, and preparation and presentation of
proofs and post-hearing briefs (unless (i) the party prevails on a claim for
which attorney's fees and expenses are recoverable under the Rules and those
amounts are included as part of the award or (ii) Executive prevails on a claim
for breach of this Agreement after the Corporation has terminated Executive
pursuant to Section 12c(ix) hereof, in which case, the Corporation will pay for
Executive's above-described fees and expenses related to such claim). Any action
to enforce or vacate the arbitrator's award shall be governed by the federal
Arbitration Act, if applicable, and otherwise by applicable state law. If either
the Corporation or Executive pursues any claim, dispute or controversy against
the other in a proceeding other than the arbitration provided for herein, the
responding party shall be entitled to dismissal or injunctive relief regarding
such action and recovery of all costs, losses and attorney's fees related to
such action. Executive acknowledges and expressly agrees that this arbitration
provision constitutes a voluntary waiver of trial by jury in any action or
proceeding to which Executive and the Corporation may be parties arising out of
or pertaining to this Agreement.

                       THE NEXT PAGE IS THE SIGNATURE PAGE

                                     - 15 -
<Page>

     IN WITNESS WHEREOF, the Corporation and Executive have duly executed this
Agreement on the dates set forth below.

                         CORPORATION:

                         GENAISSANCE PHARMACEUTICALS, INC.


                         By: /s/ Ben D. Kaplan
                             ----------------------------------------
                             Name: Ben D. Kaplan
                             Its SVP and Chief Financial Officer

                         Date:   2/23/04
                               --------------------------------------


                         EXECUTIVE:


                         /s/ Gerald F. Vovis, Ph.D.
                         --------------------------------------------
                         Name: Gerald F. Vovis, Ph.D.


                         Date:   2/20/04
                               --------------------------------------


     Personally appeared, Ben D. Kaplan, SVP and Chief Financial Officer of
Genaissance Pharmaceuticals, Inc., who acknowledged that the execution of this
Agreement was his free act and deed, and the free act and deed of the
corporation, before me, this 23rd day of February, 2004.


/s/ Marcia Passavant
-------------------------------
Notary Public
My Commission Expires: 12/31/06

     Personally appeared, Gerald F. Vovis, Ph.D, who acknowledged that the
execution of this Agreement was his free act and deed, before me, this 20th day
of February, 2004.


/s/ Marcia Passavant
-------------------------------
Notary Public
My Commission Expires: 12/31/06

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