EXHIBIT 99.4

                                VOTING AGREEMENT

     THIS VOTING AGREEMENT (this "Agreement") is made and entered into as of
June 20, 2005, by and among Clinical Data, Inc., a Delaware corporation
("Clinical Data"), Genaissance Pharmaceuticals, Inc., a Delaware corporation
(the "Company"), Randal J. Kirk ("Kirk"), RJK, L.L.C., a Virginia limited
liability company that is controlled by Kirk ("RJK"), New River Management II,
LP, a Virginia limited partnership that is controlled by Kirk ("New River"),
Kirkfield, L.L.C., a Virginia limited liability company that is controlled by
Kirk ("Kirkfield"), Third Security Staff 2001 LLC, a Virginia limited liability
company ("Staff LLC"), and Zhong Mei, L.L.C., a Virginia limited liability
company ("Zhong Mei", and collectively with Kirk, RJK, New River, and Staff LLC,
the "Stockholders", and each individually, a "Stockholder").

     WHEREAS, as of the date hereof, each Stockholder beneficially owns (as such
term is defined in Rule 13d-3 promulgated under the Securities Exchange Act of
1934, as amended, and the rules and regulations promulgated thereunder) the
number of shares of common stock, $0.01 par value (the "Common Stock") of
Clinical Data set forth opposite such Stockholder's name on Schedule A hereto
(such shares of Clinical Data's Common Stock, together with any other shares of
Clinical Data's Common Stock, sole or shared voting power over which is acquired
by such Stockholders during the period from and including the date hereof
through and including the date on which this Agreement is terminated in
accordance with its terms, collectively, the "Subject Common Shares");

     WHEREAS, Clinical Data and the Company are entering into an Agreement and
Plan of Merger, dated as of the date hereof (as the same may be amended or
supplemented, the "Merger Agreement") (terms used but not defined herein shall
have the meanings set forth in the Merger Agreement) with respect to the merger
of a subsidiary of Clinical Data with and into the Company, as a result of which
the Company shall become a wholly owned subsidiary of Clinical Data (the
"Merger"); and

     WHEREAS, as a condition to its willingness to enter into the Merger
Agreement, the Company has required that the Stockholders enter into this
Agreement whereby each Stockholder commits to cause the Subject Common Shares
over which such Stockholder has sole voting power, and to use its best efforts
to cause the Subject Common Shares over which such Stockholder has joint voting
power, to be voted in favor of the issuance of shares of Clinical Data's Common
Stock pursuant to the Merger on the terms and subject to the conditions of this
Agreement.

     NOW, THEREFORE, in consideration of the foregoing and the respective
representations, warranties, covenants and agreements contained in this
Agreement and intending to be legally bound, the parties agree as follows:

                                   ARTICLE I
                                 VOTING MATTERS

     Section 1.1 Agreement to Vote. Each Stockholder hereby agrees that from and
after the date hereof until the termination of this Agreement, at any duly
called meeting of the stockholders of Clinical Data, and in any action by



written consent of the stockholders of Clinical Data, such Stockholder shall, if
a meeting is held, appear at the meeting and any adjournment or postponement
thereof, in person or by proxy, or otherwise cause the Subject Common Shares
over which such Stockholder has sole voting power (and use their best efforts to
cause the Subject Common Shares over which such Stockholder has joint voting
power) to be counted as present thereat for purposes of establishing a quorum,
and such Stockholder shall vote or consent the Subject Common Shares over which
such Stockholder has sole voting power (and cause to be voted or consented the
Subject Common Shares over which such Stockholder has joint voting power), in
person or by proxy, (a) in favor of approving the issuance of shares of Clinical
Data's Common Stock pursuant to the Merger and each of the other transactions
and other matters specifically contemplated by the Merger Agreement, (b) in
favor of any proposal to adjourn any such meeting if necessary to permit further
solicitation of proxies in the event there are not sufficient votes at the time
of such meeting to approve the issuance of shares of Clinical Data's Common
Stock pursuant to the Merger, (c) against any action or agreement submitted for
approval of the stockholders of Clinical Data that would result in a breach of
any covenant, representation or warranty or any other obligation or agreement of
Clinical Data under the Merger Agreement or of such Stockholder under this
Agreement and (d) except as otherwise agreed in writing by the Company, against
any action, agreement, transaction or proposal submitted for approval of the
stockholders of Clinical Data that would reasonably be expected to result in any
of the conditions to Clinical Data's obligations under the Merger Agreement not
being fulfilled or that is intended, or would reasonably be expected, to
prevent, impede, interfere with, delay or adversely affect the transactions
contemplated by the Merger Agreement. Any vote by such Stockholder that is not
in accordance with this Section 1.1 shall be considered null and void. Such
Stockholder shall not enter into any agreement or understanding with any person
or entity prior to the termination of this Agreement to vote or give
instructions in a manner inconsistent with clauses (a), (b), (c) or (d) of this
Section 1.1.

     Section 1.2 Grant of Irrevocable Proxy.

          (a) Each Stockholder hereby irrevocably grants to, and appoints, the
Company and Kevin Rakin, in his capacity as Chief Executive Officer of the
Company, and any individual who shall hereafter succeed to any such office of
the Company, such Stockholder's proxy and attorney-in-fact (with full power of
substitution), for and in the name, place and stead of such Stockholder, to vote
the Subject Common Shares, or grant a consent or approval in respect of the
Subject Common Shares (i) in favor of approving the issuance of shares of
Clinical Data's Common Stock pursuant to the Merger and each of the other
transactions and other matters specifically contemplated by the Merger
Agreement, (ii) in favor of any proposal to adjourn any such meeting if
necessary to permit further solicitation of proxies in the event there are not
sufficient votes at the time of such meeting to approve the issuance of shares
of Clinical Data's Common Stock pursuant to the Merger, (iii) against any action
or agreement submitted for approval of the stockholders of Clinical Data that
would result in a breach of any covenant, representation or warranty or any
other obligation or agreement of Clinical Data under the Merger Agreement or of
such Stockholder under this Agreement and (iv) except as otherwise agreed in
writing by the Company, against any action, agreement, transaction or proposal
submitted for approval of the stockholders of Clinical Data that would
reasonably be expected to result in any of the conditions to Clinical Data's
obligations under the Merger Agreement not being fulfilled or that is intended,



or would reasonably be expected, to prevent, impede, interfere with, delay or
adversely affect the transactions contemplated by the Merger Agreement.

          (b) Each Stockholder represents that any proxies heretofore given in
respect of the Subject Common Shares are not irrevocable, and that any such
proxies are hereby revoked.

          (c) Each Stockholder hereby affirms that the irrevocable proxy set
forth in this Section 1.2 is given in connection with the execution of the
Merger Agreement, and that such irrevocable proxy is given to secure the
performance of the duties of such Stockholder under this Agreement. Each
Stockholder hereby further affirms that the irrevocable proxy is coupled with an
interest sufficient in law to support an irrevocable voting power and may under
no circumstances be revoked. Each Stockholder hereby ratifies and confirms all
that such irrevocable proxy may lawfully do or cause to be done by virtue
hereof. Such irrevocable proxy is executed and intended to be irrevocable in
accordance with Section 212(e) of the General Corporation Law of the State of
Delaware. Notwithstanding anything herein to the contrary, the parties agree
that such irrevocable proxy shall terminate and be of no further force and
effect upon the termination of this Agreement.

                                   ARTICLE II
               REPRESENTATIONS AND WARRANTIES OF THE STOCKHOLDERS

     Each of the Stockholders hereby severally represents and warrants to the
Company as follows with respect to itself only:

     Section 2.1 Organization, Good Standing and Qualification. If such
Stockholder is a business organization, such Stockholder has been duly formed,
validly existing and in good standing under the laws of the Commonwealth of
Virginia and has all requisite power and authority to own its properties and
assets and to carry on its business as now conducted. If such Stockholder is a
natural person, such Stockholder has the capacity to enter into this Agreement,
to carry out its obligations hereunder and to consummate the transactions
contemplated by this Agreement.

     Section 2.2 Authority. Each Stockholder has full power and authority to
execute and deliver this Agreement and to perform its obligations hereunder.
This Agreement has been duly and validly executed and delivered by such
Stockholder and constitutes the valid and legally binding obligation of such
Stockholder, enforceable in accordance with its terms and conditions.

     Section 2.3 Consent. No consent of any other person, and no notice to,
filing or registration with, or consent, approval or authorization of, any court
or Governmental Entity, regulatory or self-regulatory agency or any other third
party is necessary or is required to be made or obtained by such Stockholder, in
connection with the execution and delivery of this Agreement or the consummation
of the transactions contemplated hereby, other than a filing with the Securities
and Exchange Commission to amend the Stockholder's Schedule 13D relating to
Clinical Data. Stockholder represents that his spouse has no beneficial interest
in the Subject Common Shares.



     Section 2.4 Noncontravention. Neither the execution and the delivery of
this Agreement, nor the consummation of the transactions contemplated hereby,
will (i) violate any law, rule, regulation, judgment, order or decree to which
such Stockholder is subject, (ii) violate any contract, lease, license,
instrument or other legally binding arrangement or agreement to which such
Stockholder is a party or by which such Stockholder is bound, or (iii) conflict
with, result in a breach of, constitute a default under, result in the
acceleration of, create in any party the right to accelerate, terminate, modify
or cancel or require any notice under any agreement, contract, lease, license,
instrument or other legally binding arrangement or agreement to which such
Stockholder is a party or by which it is bound.

     Section 2.5 Ownership of Shares. Except as set forth on Schedule A hereto,
such Stockholder holds of record and owns beneficially and will hold of record
and own beneficially through the date this Agreement is terminated pursuant to
Section 5.1 herein the Subject Common Shares, free and clear of any restrictions
on transfer (other than restrictions under applicable securities laws), Liens,
options, warrants, purchase rights, contracts, commitments, equities, claims and
demands, except as provided in this Agreement. Schedule A hereto lists all of
the shares of Common Stock that such Stockholder owns beneficially, as of the
date hereof. Such Stockholder has not appointed or granted any proxy
inconsistent with this Agreement, which appointment or grant is still effective,
with respect to the Subject Common Shares.

     Section 2.6 Litigation. There is no litigation, arbitration proceeding,
governmental investigation, citation or action of any kind pending or, to the
knowledge of such Stockholder, proposed or threatened that seeks restraint,
prohibition, damages or other relief in connection with this Agreement or the
consummation of the transactions contemplated hereby or that otherwise might
impair the Subject Common Shares.

                                  ARTICLE III
                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

     The Company hereby represents and warrants to each Stockholder as follows:

     Section 3.1 Organization, Good Standing and Qualification. The Company is a
corporation duly formed and validly existing under the laws of the State of
Delaware and has all requisite power and authority to own its properties and
assets and to carry on its business as now conducted.

     Section 3.2 Authority. The Company has all requisite power and authority to
execute and deliver this Agreement and to perform its obligations hereunder and
thereunder. This Agreement has been duly and validly executed and delivered by
the Company and constitutes the valid and legally binding obligation of the
Company, enforceable in accordance with its terms and conditions.

     Section 3.3 Consent. No consent of any other person, and no notice to,
filing or registration with, or consent, approval or authorization of, any court
or Governmental Entity, regulatory or self-regulatory agency or any other third
party is necessary or is required to be made or obtained by the Company, in
connection with the execution and delivery of this Agreement or the consummation



of the transactions contemplated hereby, other than a filing of a Schedule 13D
relating to Clinical Data with the Securities and Exchange Commission.

     Section 3.4 Noncontravention. Neither the execution and the delivery of
this Agreement, nor the consummation of the transactions contemplated hereby,
will (i) violate the organizational documents of the Company or any law, rule,
regulation, judgment, order or decree to which the Company is subject, (ii)
violate any contract, lease, license, instrument or other legally binding
arrangement or agreement to which the Company is a party or by which the Company
is bound, or (iii) conflict with, result in a breach of, constitute a default
under, result in the acceleration of, create in any party the right to
accelerate, terminate, modify or cancel or require any notice under any
agreement, contract, lease, license, instrument or other legally binding
arrangement or agreement to which the Company is a party or by which it is bound
or to which any of its assets is subject.

     Section 3.5 Litigation. There is no litigation, arbitration proceeding,
governmental investigation, citation or action of any kind pending or, to the
knowledge of the Company, proposed or threatened that seeks restraint,
prohibition, damages or other relief in connection with this Agreement or the
consummation of the transactions contemplated hereby.

                                   ARTICLE IV
                          COVENANTS OF THE STOCKHOLDERS

     Each Stockholder severally, but not jointly and severally, hereby covenants
and agrees as follows:

     Section 4.1 Restriction on Transfer of Shares.

          (a) Such Stockholder shall not, directly or indirectly: (i) offer for
sale, sell (including short sales), transfer (including by merger, testamentary
disposition, interspousal disposition pursuant to a domestic relations
proceeding or otherwise by operation of law), tender, pledge, encumber, assign
or otherwise dispose of (including by gift) or enter into any contract, option,
derivative, hedging or other arrangement or understanding (including any
profit-sharing arrangement) with respect to or consent to the offer for sale,
sale, transfer, tender, pledge, encumbrance, assignment or other disposition of
any or all of the Subject Common Shares or any interest therein (any of the
foregoing, a "Transfer"), except to any affiliate of such Stockholder, provided
that such affiliate agrees in writing to be bound by the terms of this
Agreement, or Transfers which occur by operation of law or with the Company's
prior written consent, (ii) grant any proxies or powers of attorney (other than
pursuant to this Agreement or to an affiliate of such Stockholder that agrees in
writing to be bound by the terms of this Agreement) with respect to the Subject
Common Shares, deposit any of the Subject Common Shares into a voting trust or
enter into any other voting arrangement (other than with an affiliate of such
Stockholder that agrees in writing to be bound by the terms of this Agreement)
or permit to exist any other Lien of any nature whatsoever with respect to the
Subject Common Shares (other than such other Liens created by or arising under
this Agreement or existing by operation of law), or (iii) commit or agree to
take any of the foregoing actions.



     Section 4.2 Certain Events. Each Stockholder agrees that this Agreement and
the obligations hereunder shall attach to the Subject Common Shares and shall be
binding upon any person or entity to which legal or beneficial ownership of the
Subject Common Shares shall pass, whether by operation of law or otherwise,
including without limitation such Stockholder's administrators, successors or
receivers.

     Section 4.3 Legend. Each certificate representing Subject Common Shares
shall bear the following legend on the face thereof, if so requested by in
writing by the Company:

          "THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
RESTRICTIONS ON VOTING, TRANSFER AND CERTAIN OTHER LIMITATIONS SET FORTH IN THAT
CERTAIN VOTING AGREEMENT DATED AS OF JUNE 20, 2005 BY AND AMONG Clinical Data,
Inc., a Delaware corporation, Genaissance Pharmaceuticals, Inc., a Delaware
corporation, Randal J. Kirk ("Kirk"), RJK, L.L.C., a Virginia limited liability
company that is controlled by Kirk, New River Management II, LP, a Virginia
limited partnership that is controlled by Kirk, Kirkfield, L.L.C., a Virginia
limited liability company that is controlled by Kirk, Third Security Staff 2001
LLC, a Virginia limited liability company, and Zhong Mei, L.L.C., a Virginia
limited liability company, AS THE SAME MAY BE AMENDED FROM TIME TO TIME."

          If so requested in writing by the Company, each Stockholder will cause
all of his or its Subject Common Shares to be delivered to Clinical Data for the
purpose of applying such legend (if not so endorsed upon issuance). Clinical
Data shall return to the delivering party, as promptly as possible, any
securities so delivered. The delivery of such securities by the delivering party
shall not in any way affect such party's rights with respect to such securities.

     Section 4.4 Spousal Consent. If so required under applicable state law,
each Stockholder shall cause his spouse to duly authorize, execute and deliver
this Agreement (including the proxy granted pursuant to Section 1.2) to the
Company upon the Company's written request.

                                   ARTICLE V
                                  MISCELLANEOUS

     Section 5.1 Termination. This Agreement shall automatically terminate, and
neither the Company nor any Stockholder shall have any rights or obligations
hereunder and this Agreement shall become null and void and have no further
effect, upon the earliest to occur of (a) the mutual consent of all of the
parties hereto, (b) the Effective Time and (c) the termination of the Merger
Agreement in accordance with its terms; provided that any such termination shall
not relieve any party from liability for any intentional breach of this
Agreement (which includes, without limitation, the making of any representation
or warranty by a party in this Agreement that the party knew was not true and
accurate when made).

     Section 5.2 Non-Survival of Representations and Warranties. None of the
representations and warranties in this Agreement shall survive the termination
of this Agreement. This Section 5.2 shall not limit any covenant or agreement of
the parties contained herein which by its terms contemplates performance after
the termination of this Agreement.



     Section 5.3 Notices. Any notices or other communications required or
permitted under, or otherwise in connection with this Agreement shall be in
writing and shall be deemed to have been duly given when delivered in person or
on receipt after dispatch by first class mail, postage prepaid, addressed, or on
receipt if transmitted by national overnight courier, in each case as follows:

                  If to any Stockholder, to:        With a copy to:

                  Third Security, LLC               John Owen Gwathmey, Esq.
                  The Governor Tyler                Hunton & Williams LLP
                  1881 Grove Ave.                   Riverfront Plaza, East Tower
                  Radford, VA 24141                 951 East Byrd Street
                  Attn:  Marcus E. Smith, Esq.      Richmond, VA 23219
                  Tel:  (540) 633-7971              Tel:  (804) 788-8200
                  Fax:  (540) 633-7939              Fax:  (804) 788-8218


                  If to the Company:                With a copy to:

                  Genaissance                       Wilmer Cutler Pickering
                  Pharmaceuticals, Inc.             Hale and Dorr LLP
                  Five Science Park                 60 State Street
                  New Haven, CT 06511               Boston, MA 02109
                  Attn: Kevin Rakin                 Attn:  Steven D. Singer
                  Tel:  (203) 773-1450              Tel:  (617) 526-6000
                  Fax:  (202) 562-9377              Fax: (617) 526-5000

                  If to Clinical Data:              With a copy to:

                  Clinical Data, Inc.               McDermott Will & Emery LLP
                  2 Thurber Boulevard               28 State Street
                  Smithfield, RI 02917              Boston, MA 02109
                  Attn: Caesar Belbel               Attn:  John Hession
                  Tel:  (800) 345-2822              Tel: (617) 535-4000
                  Fax:  (800) 655-3526              Fax: (617) 535-3800

     Section 5.4 Expenses. All costs and expenses (including legal fees)
incurred in connection with this Agreement shall be paid by the party incurring
such expenses.

     Section 5.5 Headings. The headings contained in this Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

     Section 5.6 Severability. If any term or other provision of this Agreement
is invalid, illegal or incapable of being enforced by any rule of law or public
policy, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the economic or legal substance of
the transactions contemplated hereby is not affected in any manner materially
adverse to any party. Upon such determination that any term or other provision



is invalid, illegal or incapable of being enforced, the parties hereto shall
negotiate in good faith to modify this Agreement so as to effect the original
intent of the parties as closely as possible in an acceptable manner to the end
that transactions contemplated hereby are fulfilled to the extent possible.

     Section 5.7 Entire Agreement. This Agreement constitutes the entire
agreement, and supersedes all prior agreements and understandings, both written
and oral, among the parties with respect to the subject matter hereof.

     Section 5.8 Assignment. Neither this Agreement nor any of the rights,
interests or obligations hereunder shall be assigned by any of the parties
hereto, in whole or in part (whether by operation of law or otherwise), without
the prior written consent of the other parties, and any attempt to make any such
assignment without such consent shall be null and void, except any assignment in
connection with any Transfer of the Subject Common Shares permitted by this
Agreement.

     Section 5.9 Binding Effect. This Agreement shall be binding upon and inure
solely to the benefit of each party hereto and their respective successors and
assigns.

     Section 5.10 Mutual Drafting. This Agreement shall be construed without
regard to any presumption or rule requiring construction or interpretation
against the party drafting or causing this Agreement to be drafted.

     Section 5.11 Governing Law; Consent to Jurisdiction; Waiver of Trial by
Jury.

          (a) This Agreement shall be governed by and construed in accordance
with the laws of the State of Delaware, regardless of the laws that might
otherwise govern under applicable principles of conflicts of laws thereof.

          (b) Each of the parties hereto hereby irrevocably and unconditionally
submits, for itself and its property, to the exclusive jurisdiction of the
Chancery Court of the State of Delaware in any action or proceeding arising out
of or relating to this Agreement or the agreements delivered in connection
herewith or the transactions contemplated hereby or thereby or for recognition
or enforcement of any judgment relating thereto, and each of the parties hereby
irrevocably and unconditionally (i) agrees not to commence any such action or
proceeding except in such court, (ii) agrees that any claim in respect of any
such action or proceeding may be heard and determined in such court, (iii)
waives, to the fullest extent it may legally and effectively do so, any
objection which it may now or hereafter have to the laying of venue of any such
action or proceeding in such court, and (iv) waives, to the fullest extent
permitted by laws, the defense of an inconvenient forum to the maintenance of
such action or proceeding in such court. Each of the parties hereto agrees that
a final judgment in any such action or proceeding shall be conclusive and may be
enforced in other jurisdictions by suit on the judgment or in any other manner
provided by laws. Each party to this Agreement irrevocably consents to service
of process in the manner provided for notices in Section 5.3. Nothing in this
Agreement shall affect the right of any party to this Agreement to serve process
in any other manner permitted by laws.

          (c) EACH PARTY ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY
ARISE UNDER THIS AGREEMENT MAY INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND



THEREFORE IT HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY RIGHT IT MAY HAVE
TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING
OUT OF OR RELATING TO THIS AGREEMENT AND ANY OF THE AGREEMENTS DELIVERED IN
CONNECTION HEREWITH OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY. EACH
PARTY CERTIFIES AND ACKNOWLEDGES THAT (I) IT UNDERSTANDS AND HAS CONSIDERED THE
IMPLICATIONS OF SUCH WAIVERS, (II) IT MAKES SUCH WAIVERS VOLUNTARILY, AND (III)
IT HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE
MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 5.11(c).

     Section 5.12 Amendment: Waiver. No provision of this Agreement may be
waived unless in writing signed by all of the parties to this Agreement, and the
waiver of any one provision of this Agreement shall not be deemed to be a waiver
of any other provision. This Agreement may be amended, supplemented or otherwise
modified only by a written agreement executed by all of the parties to this
Agreement.

     Section 5.13 Stop Transfer Order. In furtherance of this Agreement, each
Stockholder shall and does hereby authorize and request that Clinical Data
instruct its transfer agent to enter a stop transfer order, consistent with the
terms of this Agreement and subject to such transfers as may be permitted by the
express terms hereof, with respect to all of the Subject Common Shares
beneficially owned by such Stockholder. Clinical Data hereby agrees to the
restriction on the Transfer of shares of Common Stock provided for in this
Agreement and agrees not to recognize, or authorize or permit any affiliate or
agent to recognize, any Transfer in breach of this Agreement.

     Section 5.14 Further Assurances. From time to time, at the other party's
request and without further consideration, each party hereto shall execute and
deliver such additional documents and take all such further action as may be
reasonably necessary to consummate and make effective, in the most expeditious
manner practicable, the transactions contemplated by this Agreement.

     Section 5.15 Specific Performance. The parties hereto agree that
irreparable damage would occur in the event any of the provisions of this
Agreement were not to be performed in accordance with the terms hereof and that
the parties shall be entitled to seek specific performance of the terms hereof
in addition to any other remedies at law or in equity.

     Section 5.16 Counterparts. This Agreement may be executed in one or more
counterparts, and by the different parties hereto in separate counterparts, each
of which when executed shall be deemed to be an original but all of which taken
together shall constitute one and the same agreement.



                  [remainder of page intentionally left blank]



     IN WITNESS WHEREOF, the undersigned parties have executed and delivered
this Agreement as of the day and year first above written.


                         CLINICAL DATA, INC.


                         By:      /s/ Israel M. Stein
                            ---------------------------------
                                  Name: Israel M. Stein, M.D.
                                  Title:   Chief Executive Officer


                         GENAISSANCE PHARMACEUTICALS, INC.


                         By:      /s/ Ben D. Kaplan
                            ---------------------------------
                                  Name: Ben D. Kaplan
                                  Title:   Senior Vice President and
                                           Chief Financial Officer


                         STOCKHOLDERS:


                         /s/ Randal J. Kirk
                         --------------------------------------------
                         Randal J. Kirk


                         RJK, L.L.C


                         By:      /s/ Randal J. Kirk
                            -----------------------------------------
                                  Name: Randal J. Kirk
                                  Title:   Manager


                         NEW RIVER MANAGEMENT II, LP


                         By:      /s/ Randal J. Kirk
                            -----------------------------------------
                                  Name: Randal J. Kirk
                                  Title:  Manager, Third Security, LLC, the
                                          Manager, Third Security Capital
                                          Partners, LLC, the General Partner

                            [CONTINUED ON NEXT PAGE]




                         KIRKFIELD, L.L.C.


                         By:      /s/ Randal J. Kirk
                            -----------------------------------------
                                  Name: Randal J. Kirk
                                  Title:   Manager


                         THIRD SECURITY STAFF 2001 LLC


                         By:      /s/ Randal J. Kirk
                            -----------------------------------------
                                  Name: Randal J. Kirk
                                  Title:   Manager


                         ZHONG MEI, L.L.C.


                         By:      /s/ Randal J. Kirk
                            -----------------------------------------
                                  Name: Randal J. Kirk
                                  Title:   Manager



                                   SCHEDULE A
                                   ----------

Aggregate number of shares of common stock beneficially owned by each person:
- ----------------------------------------------------------------------------

       Randal J. Kirk                        2,762,627 (1)
       RJK, L.L.C.                           579,883 (2)
       New River                             555,162 (2)
       Management II, LP
       Kirkfield, L.L.C.                     433,410 (2)
       Third Security                        112,890 (2)
       Staff 2001 LLC
       Zhong Mei, L.L.C.                     33,091 (2)


(1). 1,048,191 direct beneficial ownership with sole voting power, 1,714,436
indirect beneficial ownership with shared voting power.

(2) Direct beneficial ownership with shared voting power.