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                                                                    EXHIBIT 10.3


                         SUBLEASE TERMINATION AGREEMENT


       This Sublease Termination Agreement (the "AGREEMENT") is made this 21st
day of May, 2004, by and between Elixir Pharmaceuticals, Inc.,
successor-in-interest to Centagenetix, Inc. by merger ("SUBLESSOR"), and
Critical Therapeutics, Inc. ("SUBLESSEE").

                                    RECITALS

       A.     Sublessor is the Tenant under a lease dated January 16, 2002, by
and between Centagenetix, Inc. and Massachusetts Institute of Technology
("LANDLORD"), as landlord (said Lease, as so amended, being hereinafter referred
to as the "LEASE"), with respect to premises (the "PREMISES") consisting of
approximately 19,711 rentable square feet on the first and second floors of the
building (the "BUILDING") located at 12 Emily Street, Cambridge, Massachusetts,
as more particularly described in the Lease.

       B.     Pursuant to a sublease dated as of December 16, 2002 (the
"SUBLEASE"), Sublessee subleases a portion of the Premises from Sublessor
containing approximately 4,500 rentable square feet (the "SUBLET PREMISES") in
the Building, of which approximately 1,500 square feet is shared by Sublessor
and Sublessee.

       C.     Sublessor and Sublessee desire to terminate the Sublease prior to
the normal expiration date of the term thereof and in accordance with Section 16
of the Sublease and the terms and conditions of this Agreement. All terms used
herein and not defined herein shall have the meanings ascribed to them in the
Sublease.


                                    AGREEMENT

       NOW, THEREFORE, in consideration of the foregoing recitals and conditions
and the covenants hereinafter contained, and for other consideration hereinafter
set forth, the receipt and sufficiency of which are hereby acknowledged,
Sublessor and Sublessee hereby agree as follows:

       1.     Termination Date. The Sublease shall terminate on May 31, 2004
(hereinafter referred to as the "TERMINATION DATE"), and, prior to such
Termination Date, Sublessee shall vacate the Sublet Premises and remove its
personal goods and effects therefrom and shall otherwise quit and surrender the
Sublet Premises in a neat and clean condition and in good order, condition and
repair in substantially the same condition as of January 1, 2004, reasonable
wear and tear and damage thereto excepted, all as required by the Sublease.
Notwithstanding the foregoing, Sublessee shall not remove any of the animal
facility assets located at the Sublet Premises, including animal facility
leasehold improvements, equipment, furniture or small tools and supplies, or any
other fixtures, equipment or supplies used in housing, husbandry, cage washing
and autoclaving for animals, as further described in the Animal Care Services
Agreement between Sublessor and Sublessee dated May 15, 2003 (the "ANIMAL
FACILITY ASSETS").

       Sublessee shall maintain all of the Animal Facility Assets in good
working, operational order and shall maintain the animal facility operation at
existing standards through the day following the Termination Date when all
Sublessee's right, title and interest in and to the


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Animal Facility Assets shall vest in Sublessor. Sublessee acknowledges that
Sublessor may continue usage of the Animal Facility Assets thereafter.

       2.     Termination Consideration. In addition to paying all monthly Basic
Rent and Additional Rent and any other amounts due under the Sublease through
the Termination Date, in consideration of Sublessor's agreement to terminate the
Sublease as provided in Section 1 above, Sublessee hereby agrees that:

              (i)    Sublessor shall retain the security deposit of Sixty
                     Thousand Dollars ($60,000) under the Sublease;

              (ii)   Sublessee shall transfer legal ownership and title, free
                     and clear of all liens and encumbrances, of the Animal
                     Facility Assets to Sublessor effective as of June 1, 2004,
                     pursuant to a bill of sale of even date herewith (the "BILL
                     OF SALE"); and

              (iii)  Sublessee shall remain liable for all of its obligations
                     and liabilities under the Sublease, including any
                     environmental responsibilities, to the extent such
                     obligations and liabilities relate to events or occurrences
                     on or prior to the Termination Date, except for Basic Rent
                     and Additional Rent obligations ((i), (ii) and (iii)
                     collectively, the "TERMINATION CONSIDERATION").

       Sublessee hereby acknowledges that all monies and transfers of title
required as consideration under this Section are fully earned by Sublessor on
the Termination Date and constitute consideration for Sublessor's agreement to
terminate this Sublease under the terms of this Agreement. Sublessor hereby
acknowledges that Sublessee has paid all Basic Rent and Additional Rent due
through the Termination Date.

       3.     Indemnification by Sublessor. Sublessor shall indemnify, defend
and hold harmless the Sublessee and its affiliates, and any of their respective
directors, officers, employees, subcontractors and agents from and against any
and all liabilities, obligations, penalties, claims, judgments, demands,
actions, disbursements of any kind and nature, suits, losses, damages, costs and
expenses (including, without limitation, reasonable attorney's fees) arising out
of or in connection with any property damage or personal injury (including
without limitation death) of third parties solely to the extent such property
damages or personal injuries of third parties occur after the Termination Date.

       4.     Mutual Release. Except as to such rights or claims as may be
created or otherwise preserved by this Agreement, including those preserved
under Paragraph 2(iii) of this Agreement, and except for indemnifications by
Sublessee and Sublessor set forth in the Sublease through the Termination Date,
Sublessor and Sublessee hereby each release, remise and further discharge the
other from all debts, demands, actions, causes of action, suits, accounts,
covenants, contracts, agreements, damages and all claims and liabilities arising
out of, connected with or incidental to the Sublease or the Sublet Premises to
the extent the same relate to events or occurrences prior to the Termination
Date.



                                       2
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       5.     Conditions to Effectiveness. This Agreement is expressly subject
to the occurrence of and/or strict compliance by Sublessee and Sublessor of the
following conditions precedent:

              (i)    The execution by Sublessee and Sublessor of the Agreement;

              (ii)   The payment by Sublessee to Sublessor of all monthly Basic
       Rent, Additional Rent and any other amounts due under the Sublease
       through the Termination Date;

              (iii)  The payment by or surrender of security deposit funds and
       transfer of title of the Animal Facility Assets pursuant to the Bill of
       Sale from Sublessee to Sublessor, free and clear of all liens and
       encumbrances; and

              (iv)   The surrender of the Sublet Premises by Sublessee as
       required by Paragraph 1 hereof.

              In the event that all of the foregoing have not occurred by June
1, 2004, this Agreement shall be null and void and of no force and effect, the
Sublease shall continue in full force, and Sublessee shall not be released from
any of its obligations under the Sublease and Sublessor shall provide animal
services using the Animal Facility Assets to Sublessee on an as needed basis
under reversed terms provided in the Animal Care Services Agreement dated May
15, 2003.

       6.     Successors and Assigns. This Agreement is binding upon and shall
inure to the benefit of the Sublessor and Sublessee, with its respective agents,
employees, representatives, officers, directors, divisions, subsidiaries,
affiliates, assigns, heirs, successors-in-interest and shareholders.

       7.     Attorneys' Fees. If either party commences litigation against the
other concerning any provision of this Agreement, the rights or duties of any
person in relation thereto, or otherwise for enforcement of any remedy
hereunder, the parties hereto agree to, and hereby do waive any right to a trial
by jury and, in the event of any such commencement of litigation, the prevailing
party shall be entitled to recover from the other party such costs and
reasonable attorneys' fees as may have been incurred, as well as reasonable
attorneys' fees and costs incurred in enforcing any judgment against the
non-prevailing party.

       8.     Governing Law. This Agreement shall be governed and construed
under the laws of the Commonwealth of Massachusetts.

       9.     Counterparts. This Agreement may be executed in counterparts, each
of which shall be deemed an original, but such counterparts, when taken
together, shall constitute one agreement.

       10.    Time of the Essence. Time is of the essence of this Agreement and
the provisions contained herein.





                                       3
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       11.    Further Assurances. Sublessor and Sublessee hereby agree to
execute such further documents or instruments as may be necessary or appropriate
to carry out the intention of this Agreement.

       12.    Voluntary Agreement. The parties have read this Agreement and
mutual release as contained herein, and they have freely and voluntarily entered
into this Agreement.

       13.    No Waiver. The waiver, either expressed or implied, by any party
hereto of any term and condition of this Agreement shall not constitute a
relinquishment by said party of its right to enforce the term or condition at
any later date, unless this Agreement is amended in writing to so provide for an
unconditional waiver.

       14.    Interpretation. None of the parties hereto, nor their respective
counsel, shall be deemed to be the drafter of this Agreement for the purposes of
construing the provisions hereof. The language in all parts of this Agreement
shall in all cases be construed according to its fair meaning, not strictly for
or against any of the parties hereto.

       15.    Integration Clause/Modification. This Agreement, the Bill of Sale
and the surviving sections of the Sublease, as identified by Paragraphs 2 and 3
of this Agreement, constitute the entire agreement between the parties for the
subject matter contained herein and supersedes any and all prior agreements,
whether oral or written, related to such subject matter. This Agreement may not
be altered, amended, modified or otherwise changed in any respect whatsoever,
except by a writing duly executed by all of the parties affected by such
modification or by their authorized representatives. Any modification or waiver
of any one provision shall not constitute waiver or modification of any other
provision not expressly waived or modified.



                           [SIGNATURE PAGE TO FOLLOW]




                                       4
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       IN WITNESS WHEREOF, Sublessor and Sublessee have set their hands and
seals to this Sublease Termination Agreement as of the date first written above.



SUBLESSOR:                                      SUBLESSEE:

ELIXIR PHARMACEUTICALS, INC.                    CRITICAL THERAPEUTICS, INC.


By: /s/ Alan Watson                             By: /s/ Trevor Phillips
    ----------------------------                    ---------------------------
    Name: Alan Watson                               Name: Trevor Phillips
    Title: CBO                                      Title: COO





<PAGE>




                              WARRANTY BILL OF SALE

       KNOW ALL YE BY THESE PRESENTS, that the undersigned, CRITICAL
THERAPEUTICS, INC. having a mailing address of 60 Westview Street, Lexington,
Massachusetts 02421 (the "SELLER") for and in consideration of execution of, and
the consideration referenced in that certain Sublease Termination Agreement of
even date herewith by and between Seller and Buyer (the "SUBLEASE TERMINATION
AGREEMENT"), paid to it upon the execution and delivery of this Warranty Bill of
Sale by ELIXIR PHARMACEUTICALS, INC. having a mailing address of One Kendall
Square, Building 1000, Fifth Floor, Cambridge, MA 02139 (the "BUYER"), the
receipt whereof is hereby acknowledged and for other good and valuable
consideration, hereby grants, bargains, sells and delivers to the Buyer,
effective June 1, 2004 (the "Effective Date"), all of Seller's right, title and
interest in and to those certain goods and chattels of the Seller described as
Animal Facility Assets, as defined in the Sublease Termination Agreement, and
located at 12 Emily Street, Cambridge, Massachusetts (the "Facility") and more
specifically described in Schedule A attached hereto (the "PERSONAL PROPERTY"),
to have and to hold the Personal Property unto Buyer, its successors and
assigns, forever.

       The Seller warrants that, as of the date hereof and through the time of
transfer on the Effective Date, it is the sole and lawful owner of the Personal
Property; that the Personal Property is free from all liens and encumbrances;
and that it has good right to sell the same as aforesaid.

       Seller further warrants to Buyer that it will fully defend, protect,
indemnify and hold harmless the Buyer and its lawful successors and assigns from
any adverse claim to the Personal Property.

       The Personal Property is otherwise sold in "as is" condition and where
presently located and such Personal Property will be located in the Facility on
the Effective Date.

       IN WITNESS WHEREOF, the undersigned has caused this Warranty Bill of Sale
to be executed on this 21st day of May, 2004.



                                              CRITICAL THERAPEUTICS, INC.

                                              By: /s/ Trevor Phillips
                                                  ------------------------------
                                                  Trevor Phillips
                                                  Title: Chief Operating Officer


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                                                                      SCHEDULE A

8 Thoren racks
560 Mouse Cage Sets
280 Rat Cage Sets
5 Laminar Flow Hoods
3 VWR undercounter fridge/freezer
2 balances
4 steel tables
1 6ft carcass freezer
1 dump station
1 pass thru cage wash
1 autoclave
1 fluid solutions 140 gallon water purification system
1 TMS inverted microscope
1 inhalation anesthesia controller
1 Thermolyne Type 37900 culture incubator
8 plastic rolling carts
6 metal cages racks with covers
2 plastic lockers stacks (4 lockers per stack)
14 water bottle racks
2 cage wash racks
Many enrichment domes/bones

TISSUE CULTURE
1 TC hood
2 Heraeus incubators


Cabinets


All documentation and all manufacturer's or other warranties related to the
foregoing.