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                                                                   Exhibit 10.50



                              EMPLOYMENT AGREEMENT



     EMPLOYMENT AGREEMENT ("Agreement") made and entered into as of November 20,
2001 (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 RICHARD JUDSON, PH.D.
("Executive"), an individual who resides at 42 Barker Hill Drive, Guilford, CT
06437.

     WHEREAS, the Corporation has employed Executive as an employee at will for
a period of time and desires to extend an employment agreement to Executive; and

     WHEREAS, the Corporation desires to continue to employ Executive as Senior
Vice President, Informatics, and Executive desires to continue such employment
with the Corporation and to do so under the terms and subject to the conditions
of an employment agreement.

     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. Executive shall be employed as an officer in the capacity of
Senior Vice President, Informatics ("SVP") 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 SVP in order to advance the
Corporation's Informatics 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 SVP,
including, without limitation, managing the Corporation's Informatics team,
addressing strategic and tactical business decisions of the Corporation related
to Informatics 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.

     3. TERM. The term of Executive's employment under this Agreement shall
begin on the Effective Date, and shall expire at the close of business on
November 20, 2004, unless earlier terminated as provided in this Agreement (the
"Initial Term"). Upon expiration of the Initial Term, and each subsequent term
or extension thereof, this Agreement shall automatically be extended for an
additional term of one (1) year, unless Executive or the Corporation shall have
notified the other of his or its election to terminate this Agreement not later
than ninety (90) days prior to the end of such subsequent term or extension
thereof (the "Initial Term", together with any extensions, until termination in
accordance herewith, shall be referred to herein as the


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"Employment Term"). If the Executive continues in the full-time employ of the
Corporation after the end of the Employment Term (it being expressly understood
and agreed that the Corporation does not now, nor hereafter shall have, any
obligation to continue the Executive in its employ, whether or not on a
full-time basis, after the Employment Term ends), then the 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 the 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
     custom of the Corporation, but not less often than monthly, at an annual
     rate of $200,000, less such deductions or amounts to be withheld as shall
     be required by applicable law (the "Base Salary"). The Base Salary shall be
     reviewed annually by the CEO and shall be increased (but not decreased), if
     at all, (effective as of the commencement of each fiscal year of the
     Corporation) by such amount, if any, as the CEO, in his sole discretion,
     shall determine.

          b. BONUSES. Beginning in the year 2002, during the first quarter of
     each of the Corporation's fiscal years during the Employment Term, the
     Corporation shall pay Executive a bonus (an "Incentive Bonus") equal to
     such amount as shall be determined by the CEO in his sole discretion based
     upon Executive's achievements in meeting his performance goals and those of
     the Corporation for its most recently ended fiscal year. Thereafter, such
     goals shall be established in the first quarter of each fiscal year after
     the commencement of the Employment Term. Each Incentive Bonus may be
     payable in cash and/or stock options as determined by the CEO.

          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), including without
          limitation, all plans available to senior management, but the
          Corporation shall not be required to establish or maintain any such
          program or plan.

               (ii) Executive shall be entitled to three (3) weeks paid vacation
          during each calendar year. 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 hereunder.

               (iii) Executive shall be entitled to participate in the
          Corporation's 2000 Amended and Restated Equity Incentive Plan (the
          "Plan"). In addition, Executive



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          shall be eligible to participate in the Plan with respect to his
          future performance as a senior executive of the Corporation.

               (iv) The Corporation shall, during the Employment Term, pay the
          premiums or a portion thereof (as specified hereafter) for a
          $1,000,000 policy of term life insurance insuring the life of
          Executive (subject to his meeting the insurability requirements of the
          insurer). The Corporation shall pay the premiums for such insurance
          policy up to the cost charged by the insurer to insure a healthy 42
          year old male non-smoker. 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 of
          directors of the Corporation (the "Board"), throughout the Employment
          Term, the Corporation shall pay the costs of dues for membership in at
          least one professional organization whose activities are 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 42 year old male non-smoker.

          d. SEVERANCE BENEFIT. If the Employment Term ends as a result of
     either (i) the Executive terminating his employment pursuant to Section
     9(f) hereof, or (ii) the Corporation terminating Executive's employment
     pursuant to Section 9(d) hereof, then upon the expiration of the Employment
     Term, the Corporation shall be obligated to pay Executive the applicable
     amounts specified in Section 10.

     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, subject to reasonable documentation thereof
and the reasonable rules and regulations of the Corporation relating thereto.

     6. COVENANTS AGAINST COMPETITION.

          a. In view of the unique value to the Corporation of the services of
     Executive and because of the Corporation's confidential information that
     has been obtained by or disclosed to Executive and will be obtained by or
     disclosed to Executive hereafter, and as a material inducement to the
     Corporation to enter into this Agreement and to agree to the terms and
     conditions set forth in this Agreement, Executive covenants and agrees that
     during Executive's employment and for a period of six (6) months after he
     ceases to be employed by the Corporation for any reason, he will not,
     except as otherwise authorized by this Agreement, compete in the field of
     pharmacogenomics with the Corporation or



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     any affiliate of the Corporation, solicit the Corporation's customers or
     the customers of any of its affiliates in the field of pharmacogenomics, or
     directly or indirectly solicit for employment any of the Corporation's
     employees.

          b. For the purposes of this Agreement:

               (i) The term "compete" means engaging in the same or any similar
          business as the Corporation or any of its affiliates in any manner
          whatsoever, including without limitation as a proprietor, partner,
          investor, shareholder, member, director, officer, employee,
          consultant, independent contractor or otherwise, within any geographic
          area in which the Corporation's products are offered or distributed;

               (ii) The term "affiliate", when used in reference to any Person
          (as hereinafter defined), means any other Person that directly or
          indirectly through one or more intermediaries controls, is controlled
          by, or is under common control with the first such Person; and

               (iii) The term "customers" means all Persons 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.

               (iv) The term "Person" means any natural person, corporation,
          limited liability company, partnership of any type, proprietorship,
          other business organization, trust, union, association or governmental
          body.

          c. None of the provisions of this Section 6 shall prohibit Executive
     from investing in securities 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.

     7. REASONABLENESS OF RESTRICTIONS.

          a. Executive has carefully read and considered the provisions of
     Section 6, and, having done so, agrees that:

               (i) The restrictions set forth in Section 6, including but not
          limited to the time period, scope and geographical area of
          restriction, are fair and reasonable and are reasonably required for
          the protection of the good will and 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 provisions of this Agreement, adequate consideration for such
          obligations; and



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

          b. If, notwithstanding the foregoing, any of the provisions of Section
     6 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 6 relating to the time period and/or the areas of
     restriction and/or related aspects shall be declared by a court of
     competent jurisdiction to exceed the maximum restrictiveness such court
     deems reasonable and enforceable, the time period and/or areas of
     restriction and/or related aspects deemed reasonable and enforceable by the
     court 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.

     8. REMEDIES FOR BREACH OF EXECUTIVE'S COVENANT OF NON-COMPETITION.
Executive recognizes and agrees that the Corporation would suffer irreparable
harm due to any breach of Section 6 and that the Corporation's remedy at law for
any such breach would be inadequate, and he agrees that, for breach of such
provisions, the Corporation shall, in addition to such other remedies as may be
available to it at law or in equity or as provided in this Agreement, be
entitled to injunctive relief and to enforce its rights by an action for
specific performance.

     9. TERMINATION.

          a. In the event that Executive dies during the Employment Term, this
     Agreement shall terminate 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. 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 Corporation may, upon thirty
     (30) days prior written notice to Executive, 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
     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, less any amounts received by the
     Executive under any disability plan maintained by the Corporation.

          c. The Corporation may, upon written notice to Executive, terminate
     Executive's employment hereunder For Cause. For purposes of this Agreement,
     the term "For Cause" shall mean:


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               (i) A willful and material breach by Executive of his duties
          hereunder;

               (ii) Executive's conviction of any felony, or of a lesser crime
          having as its predicate element fraud, dishonesty or misappropriation
          of property of the Corporation;

               (iii) 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;

               (iv) Executive's engaging in chronic alcoholism, drug addiction
          or substance abuse which has interfered with the performance of his
          duties under this Agreement; and/or

               (v) Executive's perpetration of any act or omission which submits
          the Corporation to criminal liability.

          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 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 benefits pursuant to Section 10.

          d. The Corporation may, at any time, for reason other than For Cause,
     terminate Executive's employment upon at least thirty (30) days written
     notice to Executive. In the event of such termination for reason other than
     For Cause, the Corporation shall be obligated to pay Executive the
     severance payments specified in Section 10.

          e. Executive may, at his option, upon ninety (90) 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 Section 9(e), Executive's rights to receive compensation and other
     benefits (other than any Base Salary 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 pursuant to Section 10.

          f. Executive may, at his option, upon at least fifteen (15) 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 SVP, (iii)
     assigns him duties materially inconsistent with the position and/or duties
     described in Sections 1 or 2, (iv) diminishes his responsibilities
     described in Sections 1 or 2, or (v) breaches any material obligations to
     Executive under this Agreement. Upon any termination by Executive under
     this Section 9(f) the Corporation shall be obligated to pay Executive the
     severance payments specified in Section 10.



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          g. In the event of termination or expiration of Executive's employment
     other than for death, Executive shall resign 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.

     10. SEVERANCE PAYMENTS. If the Corporation terminates Executive's
employment pursuant to Section 9(d) or if Executive terminates his employment
pursuant to Section 9(f), the parties recognize and agree that actual damages
due Executive would be difficult if not impossible to ascertain and agree that,
in lieu of any other rights to which Executive may be entitled (but not in lieu
of any rights or remedies that Executive may have in respect of tortious conduct
on the part of the Corporation or in respect of any violation by the Corporation
of any employment practice, employment discrimination, age discrimination or
civil rights law or regulation applicable to the Executive), the Corporation
shall pay Executive, as severance pay or as liquidated damages, or both,
Executive's Base Salary, as in effect at the time of such termination or
expiration for a period of six (6) calendar months following the date of such
termination or expiration, such payments to be made in the same manner in which
such salary payments were made to Executive immediately prior to the date of
such termination or expiration.

     11. 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.

     12. GOVERNING LAW. This Agreement shall in all respects be subject to, and
governed by, the laws of the State of Connecticut.

     13. 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.

     14. 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, by registered or
certified mail, or (c) one day after delivery to a nationally recognized
overnight courier service which maintains a record of its deliveries. The
parties' respective addresses for such notices shall be those set forth
following their respective signatures below, or such other address or addresses
as either party may hereafter designate in writing to the other.

     15. ASSIGNMENT. This Agreement, together with any amendments hereto, shall
be binding upon and shall inure to the benefit of the parties hereto and their
respective successors, assigns, heirs, executors, and legal and personal
representatives, except that the rights and benefits of Executive under this
Agreement may not be assigned without the prior written consent of the
Corporation. Without limiting the generality of the foregoing, this Agreement



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shall be binding upon and inure to the benefit of any corporation with which or
into which the Corporation or its successors may be merged or which may succeed
to its assets or business.

     16. 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.

     17. ENTIRE AGREEMENT. This Agreement and any agreements concerning stock
option grants and confidentiality and non-disclosure executed in connection
herewith contain the entire agreement and understanding by and between Executive
and the Corporation with respect to the employment of Executive and supersede
all existing agreements between the Corporation and Executive with respect to
such employment. No representations, promises, agreements, or understandings,
written or oral, relating to the employment of Executive by the Corporation not
contained herein shall be of any force or effect.

     18. REFERENCES TO GENDER, SINGULAR 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.

     19. COUNTERPARTS; HEADINGS; SECTIONS. This Agreement may be executed in
multiple counterparts, each of which shall be considered to have the force and
effect of an 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.

     20. SURVIVAL. The covenants and agreements contained in Sections 6 through
10 shall survive any termination or expiration of this Agreement and the
termination of Executive's employment hereunder.

     21. ARBITRATION. Executive and the Corporation will submit any disputes
arising under this Agreement to an arbitration panel, consisting of one or more
natural persons (as set forth below) each of whom has experience arbitrating
employment disputes involving executives, conducting a binding arbitration in
Hartford, Connecticut, administered by the AAA (as defined hereafter) and in
accordance with the Commercial Arbitration Rules of the American Arbitration
Association ("AAA") 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 from a court of
competent jurisdiction for breach or threatened breach of Section 6. The award
of the arbitrators shall be final and shall be the sole and exclusive remedy
between the parties regarding any claims, counterclaims, issue or accounting
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 fifteen (15) days of filing a notice of arbitration, the
arbitration panel shall consist of three (3) persons, one selected by the
Corporation, one selected by Executive (or his



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representative) and one selected by the arbitrators so selected by the parties
hereto, or if the parties hereto cannot agree, selected by the manager of the
principal office of the American Arbitration Association in Hartford County in
the State of Connecticut. All fees and expenses of the arbitration charged by
the AAA, including a transcript if either party requests, shall be borne equally
by the parties. If Executive prevails as to any material issue presented in the
arbitration, the entire cost of such proceedings (including, without limitation,
Executive's reasonable attorney's fees but excluding the fees and expenses
charged by the AAA) shall be borne by the Corporation. If Executive does not
prevail as to any material issue, 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 the party prevails on a claim for which
attorney's fees are recoverable under the Rules). 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 in contravention of the arbitration procedures 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.

                       THE NEXT PAGE IS THE SIGNATURE PAGE




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     IN WITNESS WHEREOF, the Corporation and Executive have duly executed this
Agreement as of the day and year first above written.



                               CORPORATION:
                               GENAISSANCE PHARMACEUTICALS, INC.


                               By: /s/ Kevin Rakin
                                  ---------------------------------------------
                               Name: KEVIN RAKIN
                               Its: President

                               Address for Notice Purposes:
                               5 Science Park
                               Suite 2103
                               New Haven, CT 06511



                               EXECUTIVE:

                               /s/ Richard Judson, Ph.D.
                               ------------------------------------------------
                               RICHARD JUDSON, Ph.D.

                               Address for Notice Purposes:
                               42 Barker Hill Drive
                               Guilford, CT 06437


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