Document:

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                                                                   EXHIBIT 10.27

                                    AGREEMENT

         This Agreement, made and entered into this day of ("Agreement"), is by
and between Texas Biotechnology Corporation, a Delaware corporation ("Company"),
and __________________ ("Indemnitee"):

         WHEREAS, highly competent persons are becoming more reluctant to serve
publicly-held corporations as directors or in other capacities unless they are
provided with adequate protection through insurance or adequate indemnification
against inordinate risks of claims and actions against them arising out of their
service to, and activities on behalf of, the corporation; and

         WHEREAS, the current impracticability of obtaining adequate insurance
and the uncertainties relating to indemnification have increased the difficulty
of attracting and retaining such persons;

         WHEREAS, the Board of Directors of the Company (the "Board") has
determined that the inability to attract and retain such persons is detrimental
to the best interests of the Company's stockholders and that the Company should
act to assure such persons that there will be increased certainty of such
protection in the future; and

         WHEREAS, it is reasonable, prudent and necessary for the Company
contractually to obligate itself to indemnify such persons to the fullest extent
permitted by applicable law so that they will serve or continue to serve the
Company free from undue concern that they will not be so indemnified;

         WHEREAS, Indemnitee is willing to serve, continue to serve and to take
on additional service for or on behalf of the Company on the condition that he
be so indemnified; and

         NOW, THEREFORE, in consideration of the premises and the covenants
contained herein, the Company and Indemnitee do hereby covenant and agree as
follows:

         SECTION 1. Services by Indemnitee. Indemnitee agrees to serve as
_______________ of the Company. Indemnitee may at any time and for any reason
resign from such position (subject to any other contractual obligation or any
obligation imposed by operation of law), in which event the Company shall have
no obligation under this Agreement to continue Indemnitee in any such position.

         SECTION 2. Indemnification - General. The Company shall indemnify, and
advance Expenses (as hereinafter defined), to Indemnitee as provided in this
Agreement and to the fullest extent permitted by applicable law in effect on the
date hereof and to such greater extent as applicable law may thereafter from
time to time permit. The rights of Indemnitee provided under the preceding
sentence shall include, but shall not be limited to, the rights set forth in the
other Sections of this Agreement.

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         SECTION 3. Proceedings Other Than Proceedings by or in the Right of the
Company. Indemnitee shall be entitled to the rights of indemnification provided
in this Section 3 if, by reason of his Corporate Status (as hereinafter defined)
or by reason of anything done or not done by Indemnitee in any such capacity, he
is, or is threatened to be made, a party to any threatened, pending, or
completed Proceeding (as hereinafter defined), other than a Proceeding by or in
the right of the Company. Pursuant to this Section 3, Indemnitee shall be
indemnified to the full extent of the law against Expenses, judgments,
penalties, fines and amounts paid in settlement (including all interest,
assessments and other charges paid or payable in connection with or in respect
of such expenses, judgments, fines, penalties or amounts paid in settlement)
actually and reasonably incurred by him or on his behalf in connection with such
Proceeding or any claim, issue or matter therein, if he acted in good faith and
in a manner he reasonably believed to be in or not opposed to the best interests
of the Company, and, with respect to any criminal Proceeding, had no reasonable
cause to believe his conduct was unlawful.

         SECTION 4. Proceedings by or in the Right of the Company. Indemnitee
shall be entitled to the rights of indemnification provided in this Section 4
if, by reason of his Corporate Status, he is, or is threatened to be made, a
party to any threatened, pending or completed Proceeding brought by or in the
right of the Company to procure a judgment in its favor. Pursuant to this
Section, Indemnitee shall be indemnified to the full extent of the law against
Expenses actually and reasonably incurred by him or on his behalf in connection
with such Proceeding if he acted in good faith and in a manner he reasonably
believed to be in or not opposed to the best interests of the Company.
Notwithstanding the foregoing, no indemnification against such Expenses shall be
made in respect of any claim, issue or matter in such Proceeding as to which
Indemnitee shall have been adjudged to be liable to the Company if applicable
law prohibits such indemnification; provided, however, that, if applicable law
so permits, indemnification against Expenses shall nevertheless be made by the
Company in such event if and only to the extent that the Court of Chancery of
the State of Delaware, or the court in which such Proceeding shall have been
brought or is pending, shall determine.

         SECTION 5. Indemnification for Expenses of a Party Who is Wholly or
Partly Successful. Notwithstanding any other provision of this Agreement, to the
extent that Indemnitee is, by reason of his Corporate Status, a party to and is
successful, on the merits or otherwise, in any Proceeding, he shall be
indemnified against all Expenses actually and reasonably incurred by him or on
his behalf in connection therewith. If Indemnitee is not wholly successful in
such Proceeding but is successful, on the merits or otherwise, as to one or more
but less than all claims, issues or matters in such Proceeding, the Company
shall indemnify Indemnitee against all Expenses actually and reasonably incurred
by him or on his behalf in connection with each successfully resolved claim,
issue or matter. For purposes of this Section and without limitation, the
termination of any claim, issue or matter in such a Proceeding by dismissal,
with or without prejudice, shall be deemed to be a successful result as to such
claim, issue or matter.

         SECTION 6. Indemnification for Expenses of a Witness. Notwithstanding
any other provision of this Agreement, to the extent that Indemnitee is, by
reason of his Corporate Status, a

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witness in any Proceeding, he shall be indemnified against all Expenses actually
and reasonably incurred by him or on his behalf in connection therewith.

         SECTION 7. Advancement of Expenses. The Company shall advance all
reasonable Expenses incurred by or on behalf of Indemnitee in connection with
any Proceeding within two days after the receipt by the Company of a statement
or statements from Indemnitee requesting such advance or advances from time to
time, whether prior to or after final disposition of such Proceeding. Such
statement or statements shall reasonably evidence the Expenses incurred by
Indemnitee and shall include or be preceded or accompanied by an undertaking by
or on behalf of Indemnitee to repay any Expenses advanced if it shall ultimately
be determined that Indemnitee is not entitled to be indemnified against such
Expenses; provided, however, that Indemnitee shall not be required to reimburse
Company for any advancement of Expenses until a final judicial determination is
made (as to which all rights of appeal have been exhausted or lapsed).

         SECTION 8. Procedure for Determination of Entitlement to
Indemnification.

                  (a) To obtain indemnification under this Agreement, Indemnitee
shall submit to the Company a written request, including therein or therewith
such documentation and information as is reasonably available to Indemnitee and
is reasonably necessary to determine whether and to what extent Indemnitee is
entitled to indemnification. The Secretary of the Company shall, promptly upon
receipt of such a request for indemnification, advise the Board of Directors in
writing that Indemnitee has requested indemnification.

                  (b) Upon written request by Indemnitee for indemnification
pursuant to the first sentence of Section 8(a) hereof, a determination, if
required by applicable law, with respect to Indemnitee's entitlement thereto
shall be made in the specific case: (i) if a Change in Control (as hereinafter
defined) shall have occurred, by Independent Counsel (as hereinafter defined)
(unless Indemnitee shall request that such determination be made by the Board of
Directors or the stockholders, in which case by the person or persons or in the
manner provided for in clauses (ii) or (iii) of this Section 8(b)) in a written
opinion to the Board of Directors, a copy of which shall be delivered to
Indemnitee; (ii) if a Change of Control shall not have occurred, (A) by the
Board of Directors by a majority vote of a quorum consisting of Disinterested
Directors (as hereinafter defined), or (B) if a quorum of the Board of Directors
consisting of Disinterested Directors is not obtainable or, even if obtainable,
such quorum of Disinterested Directors so directs, by Independent Counsel in a
written opinion to the Board of Directors, a copy of which shall be delivered to
Indemnitee or (C) if so directed by the Board of Directors, by the stockholders
of the Company; or (iii) as provided in Section 9(b) of this Agreement; and, if
it is so determined that Indemnitee is entitled to Indemnification, payment to
Indemnitee shall be made within ten (10) days after such determination.
Indemnitee shall cooperate with the person, persons or entity making such
determination with respect to Indemnitee's entitlement to indemnification,
including providing to such person, persons or entity upon reasonable advance
request any documentation or information which is not privileged or otherwise
protected from disclosure and which is reasonably available to

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Indemnitee and reasonably necessary to such determination. Any costs or expenses
(including attorneys, fees and disbursements) incurred by Indemnitee in so
cooperating with the person, persons or entity making such determination shall
be borne by the Company (irrespective of the determination as to Indemnitee's
entitlement to indemnification) and the Company hereby indemnifies and agrees to
hold Indemnitee harmless therefrom.

                  (c) In the event the determination of entitlement to
indemnification is to be made by Independent Counsel pursuant to Section 8(b)
hereof, the Independent Counsel shall be selected as provided in this Section
8(c). If a Change of Control shall not have occurred, the Independent Counsel
shall be selected by the Board of Directors, and the Company shall give written
notice to Indemnitee advising him of the identity of the Independent Counsel so
selected. If a Change of Control shall have occurred, the Independent Counsel
shall be selected by Indemnitee (unless Indemnitee shall request that such
selection be made by the Board of Directors, in which event the preceding
sentence shall apply), and Indemnitee shall give written notice to the Company
advising it of the identity of the Independent Counsel so selected. In either
event, Indemnitee or the Company, as the case may be, may, within 7 days after
such written notice of selection shall have been given, deliver to the Company
or to Indemnitee, as the case may be, a written objection to such selection.
Such objection may be asserted only on the ground that the Independent Counsel
so selected does not meet the requirements of "Independent Counsel" as defined
in Section 17 of this Agreement, and the objection shall set forth with
particularity the factual basis of such assertion. If such written objection is
made, the Independent Counsel so selected may not serve as Independent Counsel
unless and until a court has determined that such objection is without merit.
If, within 20 days after submission by Indemnitee of a written request for
indemnification pursuant to Section 8(a) hereof, no Independent Counsel shall
have been selected without objection, either the Company or Indemnitee may
petition the Court of Chancery of the State of Delaware or other court of
competent jurisdiction for resolution of any objection which shall have been
made by the Company or Indemnitee to the other's selection of Independent
Counsel and/or for the appointment as Independent Counsel of a person selected
by the Court or by such other person as the Court shall designate, and the
person with respect to whom an objection is so resolved or the person so
appointed shall act as Independent Counsel under Section 8(b) hereof. The
Company shall pay any and all reasonable fees and expenses of Independent
Counsel incurred by such Independent Counsel in connection with acting pursuant
to Section 8(b) hereof, and the Company shall pay all reasonable fees and
expenses incident to the procedures of this Section 8(c), regardless of the
manner in which such Independent Counsel was selected or appointed. Upon the due
commencement of any judicial proceeding or arbitration pursuant to Section
10(a)(iii) of this Agreement, Independent Counsel shall be discharged and
relieved of any further responsibility in such capacity (subject to the
applicable standards of professional conduct then prevailing).

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         SECTION 9. Presumptions and Effect of Certain Proceedings.

                  (a) In making a determination with respect to entitlement to
indemnification hereunder, the person or persons or entity making such
determination shall presume that Indemnitee is entitled to indemnification under
this Agreement if Indemnitee has submitted a request for indemnification in
accordance with Section 8(a) of this Agreement, and the Company shall have the
burden of proof to overcome that presumption in connection with the making by
any person, persons or entity of any determination contrary to that presumption.

                  (b) If the person, persons or entity empowered or selected
under Section 8 of this Agreement to determine whether Indemnitee is entitled to
indemnification shall not have made a determination within 60 days after receipt
by the Company of the request therefor, the requisite determination of
entitlement to indemnification shall be deemed to have been made and Indemnitee
shall be entitled to such indemnification, absent (i) a misstatement by
Indemnitee of a material fact, or an omission of a material fact necessary to
make Indemnitee's statement not materially misleading, in connection with the
request for indemnification, or (ii) a prohibition of such indemnification under
applicable law; provided, however, that such 60-day period may be extended for a
reasonable time, not to exceed an additional 30 days, if the person, persons or
entity making the determination with respect to entitlement to indemnification
in good faith requires such additional time for the obtaining or evaluating of
documentation and/or information relating thereto; and provided, further, that
the foregoing provisions of this Section 9(b) shall not apply (i) if the
determination of entitlement to indemnification is to be made by the
stockholders pursuant to Section 8(b) of this Agreement and if (A) within 15
days after receipt by the Company of the request for such determination the
Board of Directors has resolved to submit such determination to the stockholders
for their consideration at an annual meeting thereof to be held within 75 days
after such receipt and such determination is made thereat, or (B) a special
meeting of stockholders is called within 15 days after such receipt for the
purpose of making such determination, such meeting is held for such purpose
within 60 days after having been so called and such determination is made
thereat, or (ii) if the determination of entitlement to indemnification is to be
made by Independent Counsel pursuant to Section 8(b) of this Agreement.

                  (c) The termination of any Proceeding or of any claim, issue
or matter therein, by judgment, order, settlement or conviction, or upon a plea
of nolo contendere or its equivalent, shall not (except as otherwise expressly
provided in this Agreement) of itself adversely affect the right of Indemnitee
to indemnification or create a presumption that Indemnitee did not act in good
faith and in a manner which he reasonably believed to be in or not opposed to
the best interests of the Company or, with respect to any criminal Proceeding,
that Indemnitee had reasonable cause to believe that his conduct was unlawful.

         SECTION 10. Remedies of Indemnitee.

                  (a) In the event that (i) a determination is made pursuant to
Section 8 of this Agreement that Indemnitee is not entitled to indemnification
under this Agreement, or (ii) advancement of Expenses is not timely made
pursuant to Section 7 of this Agreement, or (iii) the determination of
entitlement to indemnification is to be made by Independent Counsel pursuant to
Section 8(b) of this Agreement and such determination shall not have been made
and delivered in

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a written opinion within 90 days after receipt by the Company of the request for
indemnification, or (iv) payment of indemnification is not made pursuant to
Section 6 of this Agreement within ten (10) days after receipt by the Company of
a written request therefor, or (v) payment of indemnification is not made within
ten (10) days after a determination has been made that Indemnitee is entitled to
indemnification or such determination is deemed to have been made pursuant to
Sections 8 or 9 of this Agreement, Indemnitee shall be entitled to an
adjudication in an appropriate court of the State of Delaware, or in any other
court of competent jurisdiction, of his entitlement to such indemnification or
advancement of Expenses, and Company hereby consents to service of process and
to appear in any such proceeding. Alternatively, Indemnitee, at his option, may
seek an award in arbitration to be conducted by a single arbitrator pursuant to
the rules of the American Arbitration Association. Indemnitee shall commence
such proceeding seeking an adjudication or an award in arbitration within 180
days following the date on which Indemnitee first has the right to commence such
proceeding pursuant to this Section 10(a); provided, however, that the foregoing
clause shall not apply in respect of a proceeding brought by an Indemnitee to
enforce his rights under Section 5 of the Agreement.

                  (b) In the event that a determination shall have been made
pursuant to Section 8 of this Agreement that Indemnitee is not entitled to
indemnification, any judicial proceeding or arbitration commenced pursuant to
this Section 10 shall be conducted in all respects as a de novo trial, or
arbitration, on the merits and Indemnitee shall not be prejudiced by reason of
that adverse determination. If a Change of Control shall have occurred, in any
judicial proceeding or arbitration commenced pursuant to this Section 10 the
Company shall have the burden of proving that Indemnitee is not entitled to
indemnification or advancement of Expenses, as the case may be.

                  (c) If a determination shall have been made or deemed to have
been made pursuant to Section 8 or 9 of this Agreement that Indemnitee is
entitled to indemnification, the Company shall be bound by such determination in
any judicial proceeding or arbitration commenced pursuant to this Section 10,
absent (i) a misstatement by Indemnitee of a material fact, or an omission of a
material fact necessary to make Indemnitee's statement not materially
misleading, in connection with the request for indemnification, or (ii) a
prohibition of such indemnification under applicable law.

                  (d) The Company shall be precluded from asserting in any
judicial proceeding or arbitration commenced pursuant to this Section 10 that
the procedures and presumptions of this Agreement are not valid, binding and
enforceable and shall stipulate in any such court or before any such arbitrator
that the Company is bound by all the provisions of this Agreement.

                  (e) In the event that Indemnitee, pursuant to this Section 10,
seeks a judicial adjudication of or an award in arbitration to enforce his
rights under, or to recover damages for breach of, this Agreement, Indemnitee
shall be entitled to recover from the Company, and shall be indemnified by the
Company against, any and all expenses (of the types described in the definition
of Expenses in Section 17 of this Agreement) actually and reasonably incurred by
him in such judicial adjudication or arbitration, but only if he prevails
therein. If it shall be determined in said

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judicial adjudication or arbitration that Indemnitee is entitled to receive part
but not all of the indemnification or advancement of expenses sought, the
expenses incurred by Indemnitee in connection with such judicial adjudication or
arbitration shall be appropriately prorated.

         SECTION 11. Non-Exclusivity; Insurance; Subrogation; No Duplicate
Payments.

                  (a) The rights of indemnification and to receive advancement
of Expenses as provided by this Agreement shall not be deemed exclusive of any
other rights to which Indemnitee may at any time be entitled under applicable
law, the Certificate of Incorporation, the By-Laws, any agreement, a vote of
stockholders or a resolution of directors, or otherwise. No amendment,
alteration or repeal of this Agreement or any provision hereof shall be
effective as to any Indemnitee with respect to any action taken or omitted by
such Indemnitee in his Corporate Status prior to such amendment, alteration or
repeal.

                  (b) To the extent that the Company maintains an insurance
policy or policies providing liability insurance for directors, officers,
employees, agents or fiduciaries of the Company or of any other corporation,
partnership, joint venture, trust, employee benefit plan or other enterprise,
which such person serves at the request of the Company, Indemnitee shall be
covered by such policy or policies in accordance with its or their terms to the
maximum extent of the coverage available for any such director, officer,
employee or agent under such policy or policies.

                  (c) In the event of any payment under this Agreement, the
Company shall be subrogated to the extent of such payment to all of the rights
of recovery of Indemnitee, who shall execute all papers required and take all
action necessary to secure such rights, including execution of such documents as
are necessary to enable the Company to bring suit to enforce such rights.

                  (d) The Company shall not be liable under this Agreement to
make any payment of amounts otherwise indemnifiable hereunder if and to the
extent that Indemnitee has otherwise actually received such payment under any
insurance policy, contract, agreement or otherwise.

         SECTION 12. Binding Effect; Survival of Rights. This Agreement shall be
binding upon and inure to the benefit of and be enforceable by the parties and
their respective successors, assigns (including any direct or indirect
successors by purchase, merger, consolidation or otherwise to all or
substantially all of the business and/or assets of the Company), spouses, heirs,
executors, administrators, and personal and legal representatives. The Company
shall require and cause any successor (whether direct or indirect by purchase,
merger, consolidation or otherwise) to all, substantially all or a substantial
part, of the business and/or assets of the Company, by written agreement in form
and substance satisfactory to the Indemnitee, expressly to assume and agree to
perform this Agreement in the same manner and to the same extent that the
Company would be required to perform if no such succession had taken place. This
Agreement shall continue in effect regardless of whether Indemnitee continues to
serve as an officer or director of the Company or of any other enterprise at the
Company's request.

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         SECTION 13. Limitations Period. No legal action shall be brought and no
cause of action shall be asserted by or in the right of the Company or any
affiliate of the Company against Indemnitee, Indemnitee's spouse, heirs,
executors or personal or legal representatives after the expiration of two years
from the date of accrual of such cause of action, and any claim or cause of
action of the Company or its affiliate shall be extinguished and deemed released
unless asserted by the timely filing of a legal action within such two year
period; provided, however, that if any shorter period of limitations is
otherwise applicable to any such cause of action such shorter period shall
govern.

         SECTION 14. Severability. If any provision of this Agreement shall be
held to be invalid, illegal or unenforceable for any reason whatsoever: (a) the
validity, legality and enforceability of the remaining provisions of this
Agreement (including without limitation, each portion of any Section of this
Agreement containing any such provision held to be invalid, illegal or
unenforceable, that is not itself invalid, illegal or unenforceable) shall not
in any way be affected or impaired thereby; and (b) to the fullest extent
possible, the provisions of this Agreement (including, without limitation, each
portion of any Section of this Agreement containing any such provision held to
be invalid, illegal or unenforceable, that is not itself invalid, illegal or
unenforceable) shall be construed so as to give effect to the intent manifested
by the provision held invalid, illegal or unenforceable.

         SECTION 15. Exception to Right of Indemnification or Advancement of
Expenses. Notwithstanding any other provision of this Agreement, Indemnitee
shall not be entitled to indemnification or advancement of Expenses under this
Agreement with respect to any Proceeding, or any claim therein, brought or made
by him against the Company or the Individual Indemnitors, unless the Company has
joined in or consented to the initiation of such Proceeding.

         SECTION 16. Identical Counterparts. This Agreement may be executed in
one or more counterparts, each of which shall for all purposes be deemed to be
an original but all of which together shall constitute one and the same
Agreement. Only one such counterpart signed by the party against whom
enforceability is sought needs to be produced to evidence the existence of this
Agreement.

         SECTION 17. Headings. The headings of the paragraphs of this Agreement
are inserted for convenience only and shall not be deemed to constitute part of
this Agreement or to affect the construction thereof.

         SECTION 18. Definitions. For purposes of this Agreement:

                  (a) "Change in Control" means a change in control of the
Company occurring after the Effective Date of a nature that would be required to
be reported in response to item 6(e) of Schedule 14A of Regulation 14A (or in
response to any similar item on any similar schedule or form) promulgated under
the Securities Exchange Act of 1934 (the "Act"), whether or not the Company is
then subject to such reporting requirement; provided, however, that, without
limitation, such a Change in Control shall be deemed to have occurred if after
the Effective Date (i) any "person" (as

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such term is used in Section 13(d) and 14(d) of the Act) is or becomes the
"beneficial owner" (as defined in Rule 13d-3 under the Act), directly or
indirectly, of securities of the Company representing 10% or more of the
combined voting power of the Company's then outstanding securities without the
prior approval of at least two-thirds of the members of the Board of Directors
in office immediately prior to such person attaining such percentage interest;
(ii) the Company is a party to a merger, consolidation, sale of assets or other
reorganization, or a proxy contest, as a consequence of which members of the
Board of Directors in office immediately prior to such transaction or event
constitute less than a majority of the Board of Directors thereafter; or (iii)
during any period of two consecutive years, individuals who at the beginning of
such period constituted the Board of Directors (including for this purpose any
new director whose election or nomination for election by the Company's
stockholders was approved by a vote of at least two-thirds of the directors then
still in office who were directors at the beginning of such period) cease for
any reason to constitute at least a majority of the Board of Directors

                  (b) "Corporate Status" describes the status of a person who is
or was a director, officer, employee, agent or fiduciary of the Company or of
any other corporation, partnership, joint venture, trust, employee benefit plan
or other enterprise which such person is or was serving at the request of the
Company.

                  (c) "Disinterested Director' means a director of the Company
who is not and was not a party to the Proceeding in respect of which
indemnification is sought by Indemnitee.

                  (d) "Effective Date" means the date of this Agreement.

                  (e) "Expenses" shall include all reasonable attorneys' fees,
retainers, court costs, transcript costs, fees of experts, witness fees, travel
expenses, duplicating costs, printing and binding costs, telephone charges,
postage, delivery service fees, and all other disbursements or expenses paid or
incurred in connection with prosecuting, defending, preparing to prosecute or
defend, investigating, or being or preparing to be a witness in a Proceeding,
including on appeal.

                  (f) "Independent Counsel" means a law firm, or a member of a
law firm, that is experienced in matters of corporation law and neither
presently is, nor in the past five years has been, retained to represent: (i)
the Company or Indemnitee in any matter material to either such party, or (ii)
any other party to the Proceeding giving rise to a claim for indemnification
hereunder. Notwithstanding the foregoing, the term "Independent Counsel" shall
not include any person who, under the applicable standards of professional
conduct then prevailing, would have a conflict of interest in representing
either the Company or Indemnitee in an action to determine Indemnitee's rights
under this Agreement.

                  (g) "Proceeding" includes any action, suit, arbitration,
alternate dispute resolution mechanism, administrative hearing, inquiry or
investigation, whether civil, criminal, administrative or other (whether
instituted by the Company or any other party), or any inquiry or investigation
that

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Indemnitee in good faith believes might lead to the institution of any such
action, suit, or proceeding, whether civil, criminal, administrative,
investigative, or other; Notwithstanding the foregoing, the term "Proceeding"
shall not include any action, suit, arbitration, alternate dispute resolution
mechanism, administrative hearing, or any inquiry or investigation initiated by
an Indemnitee pursuant to Section 10 of this Agreement to enforce his rights
under this Agreement.

         SECTION 19. Modification and Waiver. No supplement, modification or
amendment of this Agreement shall be binding unless executed in writing by both
of the parties hereto. No waiver of any of the provision of this Agreement shall
be deemed or shall constitute a waiver of any other provision hereof (whether or
not similar) nor shall such waiver constitute a continuing waiver.

         SECTION 20. Notice by Indemnitee. Indemnitee agrees promptly to notify
the Company in writing upon being served with any summons, citation, subpoena,
complaint, indictment, information or other document relating to any Proceeding
or matter which may be subject to indemnification or advancement of Expenses
covered hereunder.

         SECTION 21. Notices. All notices, requests, demands and other
communications hereunder shall be in writing and shall be deemed to have been
duly given if (i) delivered by hand and receipted for by the party to whom said
notice or other communication shall have been directed, or (ii) mailed by
certified or registered mail with postage prepaid, on the third business day
after the date on which it is so mailed:

                  (a) If to Indemnitee, to:

                                ------------------------------------------------

                                ------------------------------------------------

                                ------------------------------------------------

                  (b) If to the Company, to:

                                Texas Biotechnology Corporation
                                7000 Fannin, Suite 1920
                                Houston, Texas 77030

or to such other address as may have been furnished to Indemnitee by the Company
or to the Company by Indemnitee, as the case may be.

         SECTION 22. Governing Law. The parties agree that this Agreement shall
be governed by, and construed and enforced in accordance with, the laws of the
State of Delaware.

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         SECTION 23. Miscellaneous. Use of the masculine pronoun shall be deemed
to include usage of the feminine pronoun where appropriate.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement on
the day and year first above written.

                                    TEXAS BIOTECHNOLOGY CORPORATION

                                    By:
                                        ----------------------------------------

                                    Indemnitee

                                    --------------------------------------------

                                       11<PAGE>
                                                                   EXHIBIT 10.28

                              RETIREMENT AGREEMENT

         This Retirement Agreement (the "Agreement") is dated March 21, 2002,
and effective on the date described in Section 12.3 (the "Effective Date"). This
Agreement is made as a mutually agreed compromise among the parties for the
complete and final settlement of all claims, differences, and alleged causes of
action existing between them as of the Effective Date of this Agreement.

                                     PARTIES

         The Parties to this Agreement are Texas Biotechnology Corporation (the
"Company") and David B. McWilliams ("Executive"). The Company and Executive are
referred to collectively as the "Parties."

                                    PREAMBLE

         WHEREAS, Executive was previously employed as the President and Chief
Executive Officer of the Company, pursuant to an Employment Agreement dated July
15, 1992, as amended (the "Employment Agreement");

         WHEREAS, Executive and the Company also entered into a Termination
Agreement dated July 1, 1995 (the "Termination Agreement");

         WHEREAS, Executive held certain other positions as an employee, officer
or director of certain subsidiaries and affiliates of the Company;

         WHEREAS, Executive's last day of employment as President and Chief
Executive Officer of the Company pursuant to the Employment Agreement shall be
March 25, 2002 (the "Resignation Date");

         WHEREAS, the Parties intend that this Agreement shall govern all issues
related to Executive's employment and separation from the Company;

         WHEREAS, Executive has had at least 21 days to consider this Agreement;

         WHEREAS, the Company has advised Executive in writing to consult with a
lawyer;

         WHEREAS, Executive has had an opportunity to consult with independent
counsel with respect to the terms, meaning and effect of this Agreement;

         WHEREAS, Executive understands that the Company regards the above
representations as material and that the Company is relying on these
representations in entering into this Agreement; and

         WHEREAS, the Parties desire to settle and compromise any and all claims
or potential claims between them which arose on or before the Effective Date of
this Agreement.

<PAGE>

         NOW, THEREFORE, in consideration of the mutual promises and obligations
contained in this Agreement and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the Parties agree as
follows:

         1.  Definitions.

         1.1 When used in this Agreement, "Company and/or its Affiliates" shall
mean and include Texas Biotechnology Corporation, a Delaware corporation, and
all of its predecessors, successors, parents, subsidiaries, divisions or other
affiliated companies, partners, partnerships, assigns, present and former
officers, directors, employees, shareholders, agents, employee benefit plans and
plan fiduciaries, whether in their individual or official capacities.

         2.  Resignation by Executive.

         2.1 Effective on the Resignation Date, Executive hereby resigns all
positions he holds as an officer or director of the Company and/or its
Affiliates, and agrees to provide a letter of resignation to the Company in the
form attached as Exhibit 1; provided, that the Executive may remain as a
director of Structural Bioinformatics, Inc. and may retain all options and stock
in that entity held by him on the Resignation Date.

         2.2 The Parties agree that the Company may publish the press release
attached as Exhibit 2 to this Agreement.

         2.3 (a) In further consideration of the compensation to be paid by the
Company to the Executive under this Agreement, the Executive agrees to make
himself available to the Company during normal business hours for a period of up
to six weeks after the Resignation Date. The duration of this time period will
be at the discretion of the Chairman of the Board of Directors of the Company in
consultation with the new CEO, if any, and may include all, any portion or none
of the six weeks period after the Resignation Date (this time period, if any, as
determined by the Chairman of the Board is herein referred to as the "Transition
Period"). During the Transition Period, the Executive will reasonably assist and
cooperate with the Company's new CEO, if any, and its other officers and
employees at reasonable times, in order to provide for an orderly transition
between the Executive and the Company's new CEO. Such reasonable assistance and
cooperation may include, but not be limited to, providing information and
assistance regarding the Company's research and development programs, capital
and operating budgets, personnel matters, investor relations issues, financings
and investment banking relationships, collaborations and partnerships and
regulatory matters. The Executive will also, at the request of the CEO of the
Company, be involved at reasonable times in meetings with Company personnel or
third parties. Any expenses incurred by the Executive (if requested by the
Company) while providing the services during the Transition Period will be
reimbursed in accordance with the Company's standard policy.

             (b) During the Transition Period, the Executive will have the
status of an employee. During the Severance Period, the Executive will also have
the status of an employee, and will be available to provide reasonable services
at reasonable times at the request of the Company consistent with the services
provided by the Executive during the Transition Period up to a maximum of 16
hours per month. After the Severance Period, the Executive will no longer be an
employee. Subject to the compliance by the Executive with his obligations in
Sections 2.3, and 3 of this Agreement, the Executive

                                       2
<PAGE>
will be free to seek and
obtain other employment during the Transition Period and the Severance Period
and thereafter, and the Company shall continue to make the payments and provide
the benefits to Executive as set forth in this Agreement.

         3. Termination of the Employment Agreement. The Parties agree that the
Employment Agreement is hereby terminated and of no further force and effect as
of the Resignation Date, except that the following paragraphs shall survive
termination, in accordance with their terms: 11, 12, 13 and 14; provided,
however, that paragraph 14 of the Employment Agreement shall terminate and be of
no further force and effect on the last day of the Severance Period. The Parties
further agree that the Termination Agreement is hereby terminated and of no
further force and effect as of the date of this Agreement. Executive's agreement
to terminate the Termination Agreement has been induced by, and is based on, the
representation of the Company to the Executive that the Company is not presently
aware of any fact or circumstance that could result in a change of control or
potential change of control of the Company within the meaning of the Termination
Agreement. This Agreement does not affect the Proprietary Information, Patent
and Copyright Agreement dated July 15, 1992 (the "Patent Agreement") and the
Agreement dated May 3, 1996 (the "Indemnification Agreement"), entered into by
the Executive and the Company, which the Parties acknowledge and agree will
remain in effect in accordance with their terms.

         4.  Severance Payments to Executive.

         4.1 The Company agrees to continue to pay Executive his salary at a
monthly rate of $27,083.33 during the Transition Period, and during a period of
twelve (12) months following the Transition Period (the "Severance Period"), on
the dates and in the manner the Company presently pays its other employees.

         4.2 During the Transition Period and the Severance Period, the Company
will provide, at no cost to the Executive, medical, dental and life insurance to
the Executive on the same terms as are in effect on the Resignation Date;
provided, however, that (a) the Company may provide this coverage by converting
existing policies or purchasing new policies (subject to the Executive
successfully completing any required examinations); (b) if the Company's dental
insurance plan does not provide coverage to the Executive, then the Company will
reimburse the Executive for all covered dental expenses, subject to the same
claims procedures, limits, contributions and deductibles as if Executive were
still covered under the Company's current dental insurance plan; and (c) with
respect to the Company's long term disability insurance plan, the Parties agree
that the Executive shall not be eligible for coverage after the Transition
Period, and the Company shall have no obligation to obtain or pay for any
conversion or continuation coverage thereafter.

         4.3 During the Transition Period and the Severance Period, the
Executive shall continue to participate under the Company's 401(k) plan.

         4.4 In further consideration of Executive's release, the Company agrees
to pay Executive an amount equal to $6250 per week of unused vacation time
accrued as of the Resignation Date in accordance with existing Company policy.
This payment will be made in a lump sum on the first payroll date following the
Effective Date. No additional vacation time will accrue during the Transition
Period and the Severance Period or thereafter.

                                       3
<PAGE>
         4.5 If Executive timely elects to continue his group medical insurance
coverage under COBRA, then Executive shall be responsible for all premiums to
maintain such coverage (to the extent such coverage is available) after the
Severance Period.

         4.6 The Compensation Committee of the Board of Directors of the Company
(the "Compensation Committee") has determined that the Executive's bonus for
2001 under the Company's 2001 Incentive Plan for Senior Executives (the
"Incentive Plan") is $122,363. The bonus will be paid on or before the
Resignation Date one-half in cash ($61,181.79) and one-half in shares of fully
vested restricted stock (10,867 shares).

         4.7 The Compensation Committee has also granted the Executive 62,500
stock options based on his performance of his individual goals in 2001. These
options have a three year term and will vest as to one-third of the shares on
each of the first, second and third anniversaries of the date of grant;
provided, that these options will not be subject to any other conditions
regarding their exercise (such as continued employment) and that the only
condition to exercise is the passage of the time periods set forth herein. Such
options will be exercisable for 90 days after the expiration date. The option
agreement regarding these options will be delivered to the Executive on or
before the Resignation Date.

         5.  Stock Options & Restricted Stock.

         5.1 Executive and the Company agree that Executive holds certain
restricted stock and certain options to purchase the common stock of the
Company, as described on the attached Exhibit 3.

         5.2 In further consideration of Executive's release, the Company agrees
that:

             a. the options to acquire common stock of the Company held by the
Executive as set forth on Exhibit 3 (the "Options") shall continue to vest and
be exercisable (or will terminate) in accordance with their terms during the
Transition Period and the Severance Period;

             b. On the last day of the Severance Period (the "Vesting Date"),
all outstanding Options that expire in 2006 or later will become fully vested
and will be exercisable until 24 months after the Vesting Date, and thereafter
will be exercisable for the remaining time period set forth in the stock option
plan under which they were issued (90 days after termination under the 1999
Plan, one month after termination under the 1995 Plan and three months after
termination under the 1992 Plan); provided, however, that all Options shall
become fully vested and immediately exercisable upon a "Change of Control" as
defined in the applicable stock option plan;

             c. On the Vesting Date, all outstanding Options that expire in 2005
or earlier will terminate and thereafter will be exercisable for the remaining
time period set forth in the stock option plan under which they were issued (90
days after termination under the 1999 Plan, one month after termination under
the 1995 Plan and three months after termination under the 1992 Plan); and

             d. On the Effective Date, all of the shares of restricted stock of
the Company held by the Executive as set forth on Exhibit 3 which are unvested
and subject to restrictions will be fully vested and all restrictions will be
removed as of the Effective Date.

                                       4
<PAGE>
         6.  Tax Withholding.

         6.1 All payments made or other consideration granted to Executive under
this Agreement may be reduced by the amount of taxes required to be withheld
under applicable federal, state, city, or other law, as determined in the
Company's reasonable discretion.

         7.  Release by Executive.

         7.1 In consideration of the Company's payments and other concessions
described above, Executive releases, discharges and forever holds harmless the
Company and its Affiliates from any and all claims, known or unknown, arising on
or before the Effective Date of this Agreement, except as described in Section
7.5 below.

         7.2 This release includes, but is not limited to, any claims arising
out of the Employment Agreement or the Termination Agreement (other than claims
based on the breach by the Company of its representations in Section 3 above
regarding the Termination Agreement); any claims for any wages, salary,
compensation, sick time, vacation time, paid leave or other remuneration of any
kind; any claim of discrimination and/or retaliation on the basis of race, sex,
religion, marital status, sexual preference, national origin, handicap or
disability, veteran status, or special disabled veteran status; any claim
arising under Title VII of the Civil Rights Act of 1964, the Civil Rights Act of
1991, the Age Discrimination in Employment Act of 1967, the Employee Retirement
Income Security Act of 1974, the Americans with Disabilities Act, the Family and
Medical Leave Act, the Fair Labor Standards Act of 1938, the Texas Commission on
Human Rights Act, Chapter 451 of the Texas Labor Code, or the Texas Payday Law,
as such statutes may be amended from time to time; any claim arising out of or
related to an express or implied employment contract; any other contract
affecting terms and conditions of employment, or a covenant of good faith and
fair dealing; and any personal gain with respect to any claim arising under the
qui tam provisions of any state or federal law.

         7.3 Executive represents that he understands this release, understands
that rights and claims under the Age Discrimination in Employment Act of 1967,
as amended, are among the rights and claims against the Company he is releasing
and understands that he is not releasing any rights or claims arising after the
Effective Date.

         7.4 Executive agrees that the consideration for his release is in
addition to anything of value to which he already is entitled from the Company
and/or its Affiliates.

         7.5 Notwithstanding anything to the contrary herein, Executive is not
releasing any right related to (a) any vested benefit under any employee benefit
plan, as defined by the Employee Retirement Income Security Act of 1974, as
amended; (b) stock options or restricted stock described in this Agreement; (c)
any rights to COBRA continuation coverage; (d) any rights related to this
Agreement or the Indemnification Agreement; or (e) any amounts owing to
Executive by the Company for previously earned compensation or reimbursement for
expenses.

         8.  Release by Company.

         8.1 In consideration of Executive's release, the Company releases,
discharges and forever holds harmless Executive from any and all claims, known
or unknown, arising on or before the Effective Date of this Agreement, except
that the Company is not releasing any rights related to this Agreement.

                                       5
<PAGE>

         9.   Confidentiality.

         9.1  Until the conclusion of the Severance Period, both Parties shall
keep strictly confidential all the terms and conditions, including amounts, in
the Agreement and shall not disclose them to any person other than legal and/or
financial advisors, government officials who seek such information in the course
of their official duties, individuals at the Company responsible for
implementing the Agreement, or Executive's spouse, unless compelled to do so by
law or regulation, or business necessity (including SEC or tax reporting
obligations). Nothing in this Section is intended to prevent Executive from
disclosing the fact that he was employed by the Company or from describing his
employment duties.

         10.  Litigation Support.

         10.1 In the event and for so long as the Company is actively contesting
or defending against any action, suit, proceeding, hearing, investigation,
charge, complaint, claim, or demand brought against (a) the Company and/or its
Affiliates or (b) the Executive in his capacity of employee, director or officer
of the Company in connection with any fact, situation, circumstance, status,
condition, activity practice, plan, occurrence, event, incident, action, failure
to act, or transaction involving the Company, then Executive will reasonably
cooperate with the Company or its counsel in the contest or defense, and provide
such testimony and access to his books and records as shall be reasonably
necessary in connection with the contest or defense, all at the sole cost and
expense of the Company. The Executive further agrees to not provide assistance
of any kind, other than as required by law, to any party to assist in pursuing
any currently pending or threatened claim, litigation, arbitration, mediation,
administrative hearing or other legal proceedings against the Company.

         10.2 The Company acknowledges and agrees that if Executive is
individually brought into any litigation in connection with the Company and/or
its Affiliates, then Executive shall be indemnified by the Company and/or its
Affiliates to the maximum extent that directors and officers of corporations are
permitted to be indemnified under Delaware law both for all costs of litigation,
as well as any judgments or settlement amounts paid.

         11.  Return of Company Materials.

         11.1 Executive agrees to deliver promptly to the Company all originals
and copies of materials in the Executive's possession, custody, or control
containing confidential information of the Company.

         12.  Acceptance, Revocation and Effective Date.

         12.1 The Company advises Executive to consult with an attorney prior to
executing this Agreement, and Executive acknowledges being given that advice.

         12.2 Executive, at his sole discretion, may revoke this Agreement on or
before the expiration of seven calendar days after signing it (the "Revocation
Period"). Revocation shall be in writing and effective upon dispatch to the
following:

                                       6
<PAGE>

                        Texas Biotechnology Corporation
                        Attn: Stephen L. Mueller
                        7000 Fannin, Suite 1920
                        Houston, Texas 77030

                        with a copy to:
                        Porter & Hedges, L.L.P.
                        Attn: Robert G. Reedy
                        700 Louisiana, Suite 3500
                        Houston, Texas 77002

If Executive timely elects to revoke the Agreement, all of the provisions of
this Agreement shall be void and unenforceable.

         12.3 This Agreement shall become effective and enforceable immediately
upon expiration of the Revocation Period (the "Effective Date").

         13.  Dispute Resolution.

         13.1 Any dispute arising out of or relating to this Agreement, or any
breach thereof, shall be resolved by binding arbitration in Houston, Texas, in
accordance with the Employment Arbitration Rules of the American Arbitration
Association then in effect, as amended by this Agreement, and judgment on the
award rendered by the arbitrator may be entered in any court of competent
jurisdiction. The parties agree that the arbitrator shall have no power or
authority to make awards or issue orders of any kind except as expressly
permitted by this Agreement. The arbitrator's decision shall follow the plain
meaning of the relevant documents, apply Texas law, and shall be final and
binding. The location of such arbitration in Houston, Texas, shall be selected
by the Company in its sole and absolute discretion. All costs and expenses,
including attorneys' fees, relating to the resolution of any such dispute shall
be borne by the party incurring such costs and expenses.

         13.2 Notwithstanding the preceding paragraph, the Parties acknowledge
that either of them may seek emergency or temporary injunctive relief, but
absolutely no other relief, in any court of competent jurisdiction. All other
disputes, claims and remedies shall be settled by arbitration in accordance with
Section 13.1.

         14.  No Defamatory Statements.  Executive and the Company agree that
neither will make statements about the other at any time that are slanderous,
libelous or defamatory.

                                       7
<PAGE>

         15.  Miscellaneous.

         15.1 The Parties acknowledge that this Agreement is the result of a
compromise and shall never be construed as, or said by either of them to be, an
admission by the other of any liability, wrongdoing, or responsibility. The
Parties expressly disclaim any such liability, wrongdoing, fault, or
responsibility.

         15.2 This Agreement, the surviving paragraphs of the Employment
Agreement, the Patent Agreement, the Indemnification Agreement and agreements
and documents related to stock options, restricted stock and other benefit plans
constitute the entire agreement between the Parties. This Agreement may be
executed in identical counterparts, each of which shall constitute an original
and all of which shall constitute one and the same agreement.

         15.3 The Parties warrant that no representations have been made other
than those contained in the written provisions of this Agreement, and that they
do not rely on any representations not stated in this Agreement.

         15.4 The Parties further warrant that they or their undersigned
representatives are legally competent and fully authorized to execute and
deliver this Agreement.

         15.5 The Parties confirm they have had the opportunity to have this
Agreement explained to them by attorneys of their choice, and that they execute
this Agreement freely, knowingly and voluntarily. The Company is relying on its
own judgment and on the advice of its attorneys and not upon any recommendation
of Executive or his agents, attorneys or other representatives. Likewise,
Executive is relying on his own judgment and on the advice of his attorneys, and
not upon any recommendation of the Company or its directors, officers,
employees, agents, attorneys or other representatives. By voluntarily executing
this Agreement, both Parties confirm their competence to understand and do
hereby accept the terms of this Agreement as resolving fully all differences,
disputes and claims that may exist within the scope of this Agreement.

         15.6 Executive represents that he has not filed or authorized the
filing of any complaints, charges or lawsuits against the Company and/or its
Affiliates with any federal, state or local court, governmental agency, or
administrative agency, and that if, unbeknownst to Executive, any such complaint
has been filed on his behalf, he will use his best efforts to cause it to
immediately be withdrawn and dismissed with prejudice.

         15.7 The Company represents that it has not filed or authorized the
filing of any complaints, charges or lawsuits against Executive with any
federal, state or local court, governmental agency, or administrative agency,
and that if, unbeknownst to the Company, any such complaint has been filed on
its behalf, it will use his best efforts to cause it to immediately be withdrawn
and dismissed with prejudice.

         15.8 This Agreement may not be modified or amended except by a writing
signed by all Parties. No waiver of this Agreement or of any of the promises,
obligations, terms, or conditions contained in it shall be valid unless it is in
writing signed by the Party against whom the waiver is to be enforced.

         15.9 If any part or any provision of this Agreement shall be finally
determined to be invalid or unenforceable under applicable law by a court of
competent jurisdiction, that part shall be ineffective to the extent of such
invalidity or unenforceability only, without in any way affecting the remaining
parts of said provision or the remaining provisions of the Agreement.

                                       8
<PAGE>
         15.10 The Parties have cooperated in the preparation of this Agreement.
Hence, the Agreement shall not be interpreted or construed against or in favor
of any Party by virtue of the identity, interest, or affiliation of its
preparer.

         15.11 This Agreement is made and shall be enforced pursuant to the laws
of the State of Texas, without regard to its law governing conflicts of law. All
performance required by the terms of this Agreement shall take place in Harris
County, Texas.

                            [SIGNATURE PAGE FOLLOWS]

                                       9
<PAGE>
David B. McWilliams  ("Executive")          TEXAS BIOTECHNOLOGY
                                            CORPORATION ("Company")

                                            By: /s/ JOHN M. PIETRUSKI
                                               ---------------------------------
                                            Printed Name: John M. Pietruski
                                                         -----------------------
                                            Title:   Chairman of the Board
                                                  ------------------------------
                                            Date:    March 21, 2002
                                                 -------------------------------
Date: /s/ DAVID B. McWILLIAMS
     --------------------------

            THIS AGREEMENT CONTAINS A BINDING ARBITRATION PROVISION.

<PAGE>

                          EXHIBIT 1: RESIGNATION LETTER

<PAGE>
March 21, 2002

Texas Biotechnology Corporation
Attn: Chairman of the Board
7000 Fannin, Suite 1920
Houston, Texas 77030

Ladies and Gentlemen:

             Please accept this letter as my resignation from all positions as
an officer and director of Texas Biotechnology Corporation, and all its
subsidiaries (including without limitation, Revotar Biopharmaceuticals AG,
Immunopharmaceutics, Inc., ICOS - Texas Biotechnology, L.P., and TBC - ET, Inc.
but excluding Structural Bioinformatics, Inc.), effective March 25, 2002.

Sincerely,

/s/ DAVID B. McWILLIAMS
David B. McWilliams

<PAGE>

                         EXHIBIT 2: AGREED PRESS RELEASE

<PAGE>
Contact:      Pamela M. Murphy, Vice President, Corporate Communications
              Texas Biotechnology
              (713) 796-8822

           TEXAS BIOTECHNOLOGY CORPORATION NAMES BRUCE D. GIVEN, M.D.,
            PRESIDENT AND CEO; REPLACES RETIRING DAVID B. MCWILLIAMS

HOUSTON, TEXAS: MARCH 21, 2002 TEXAS BIOTECHNOLOGY CORPORATION (NASDAQ: TXBI)
announced today the election of Bruce D. Given, M. D., as President, Chief
Executive Officer and a member of the Board of Directors effective March 25,
2002. Dr. Given joins Texas Biotechnology from Johnson & Johnson where he was
President, International of Ortho-Clinical Diagnostics. Recent positions at J&J
included Group V.P. and Head, Worldwide Clinical and Regulatory Affairs at
Biosense Webster and Group V.P. and Head U.S. Marketing, Sales and R&D at
Janssen Pharmaceutica. Dr. Given joined J&J in 1993. Previously he had been with
Sandoz Pharma, LTD and Schering-Plough Corporation. Dr. Given is an honors
graduate of the University of Chicago Pritzker School of Medicine, and was a
Clinical Fellow at the Harvard Medical School.

John M. Pietruski, Chairman of the Board said, "We are very fortunate to have
attracted a person of Bruce's extensive experience in Marketing, Sales, R&D and
Clinical Development. We are confident Texas Biotechnology and its shareholders
will benefit from his strong leadership." Dr. Given commented that he "was
delighted to join the talented team at TBC and is looking forward to the
opportunity to help build an increasingly successful business leading to
enhanced shareholder value."

At the same time, Texas Biotechnology announced that David B. McWilliams will
retire. Mr. McWilliams has served as President, CEO and a director since joining
the company in 1992. Mr. McWilliams stated, "It has been a gratifying experience
to participate with a group of dedicated people in developing a very fine
company." Mr. Pietruski said, "We very much appreciate David's contribution to
the growth of the Company from an embryonic R&D company to its current level of
development. We wish him well in his retirement."

Texas Biotechnology, a biopharmaceutical company focused on the discovery,
development and commercialization of novel drugs, is recognized for its
expertise in small molecule drug development and vascular biology. Argatroban,
its first FDA-approved product, is being marketed by GlaxoSmithKline for
heparin-induced thrombocytopenia. Additional studies are seeking to broaden this
initial indication for Argatroban in ischemic stroke, angioplasty and
hemodialysis. Texas Biotechnology has several other products in clinical
development for pulmonary arterial hypertension, essential hypertension,
congestive heart failure and asthma. To learn more about Texas Biotechnology
please go to our website www.tbc.com.

<PAGE>

This press release contains "forward-looking statements" within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. These forward-looking statements
are subject to certain risks, trends and uncertainties that could cause actual
results to differ materially from those projected. Among those risks, trends and
uncertainties are timing and cost of our clinical trials, attainment of research
and clinical goals and milestones of product candidates, attainment of required
governmental approval, sales levels of our products and availability of
financing and revenues sufficient to fund development of product candidates and
operations. In particular, careful consideration should be given to cautionary
statements made in the various reports Texas Biotechnology has filed with the
Securities and Exchange Commission. The Company undertakes no duty to update or
revise these forward-looking statements.

<PAGE>

               EXHIBIT 3: SCHEDULE OF OPTIONS AND RESTRICTED STOCK

<PAGE>
DAVID B. MCWILLIAMS
STOCK OPTIONS OUTSTANDING & RESTRICTED STOCK
AS OF MARCH 8, 2002

STOCK OPTIONS

<Table>
<Caption>
                                                                                         Options Vested
                                                                                                At
Option  Option    Grant    Extension  Expiration               Exercise  --------------------------------------------------
Number   Plan     Date       Date        Date     Outstanding    Price   3/8/2002  3/13/2002  9/8/2002  3/6/2003  3/13/2003
------  ------    -----    ---------  ----------  -----------  --------  --------  ---------  --------  --------  ---------
<S>     <C>     <C>        <C>        <C>         <C>          <C>       <C>       <C>        <C>       <C>       <C>
   235   1995    4/5/1995              4/5/2005       62,500     1.3100    62,500
   325   1995    3/5/1996              3/5/2006       75,000     4.3750    75,000
   413   1995    3/4/1997              3/4/2007       17,021     5.8750    17,021
   414   1995    3/4/1997              3/4/2007      102,979     5.8750   102,979
E00013   1992   6/30/1992   1/3/1997  7/16/2002      142,858     3.5000   142,858
E00069   1992    1/1/1994  5/30/1997   1/1/2004       65,000     5.3000    65,000
E00070   1992   3/15/1994  5/30/1997  3/15/2004       11,361     5.3600    11,361
E00071   1992   7/26/1993  5/30/1997  7/26/2003       42,858     3.5000    42,858
   466   1995    3/3/1998              3/3/2008      123,125     7.1875   123,125
   559   1992    3/2/1999              3/2/2009        7,083     4.1875     7,083
   627   1992    3/2/1999              3/2/2009       14,167     4.1875    14,167
   648   1999    3/6/2000              3/6/2010        8,463    20.1250     3,495                          4,968
A00648   1999    3/6/2000              3/6/2010       14,037    20.1250    11,505                          2,532
   823   1995    9/8/2000              9/8/2010       34,323    16.9375    11,441               11,441
   833   1995   3/13/2001             3/13/2111       45,000     5.5100               15,000                         15,000
   834   1999   3/13/2001             3/13/2111       18,148     5.5100
   835   1999   3/13/2001             3/13/2011       52,477     5.5100               23,542                         23,542
   836   1999   3/13/2001             3/13/2011      100,000     5.5100               33,334                         33,333
                                                     -------              -------     ------    ------     -----     ------

                                                     936,400              690,393     71,876    11,441     7,500     71,875
                                                     =======              =======     ======    ======     =====     ======
</Table>

<Table>
<Caption>
                                  Options Vested
                                        At
Option                          -------------------
Number                          9/8/2003  3/13/2004
------                          --------  ---------
<S>                             <C>       <C>
   235
   325
   413
   414
E00013
E00069
E00070
E00071
   466
   559
   627
   648
A00648
   823                            11,441
   833                                       15,000
   834                                       18,148
   835                                        5,393
   836                                       33,333
                                  ------     ------

                                  11,441     71,874
                                  ======     ======
</Table>

RESTRICTED STOCK

<Table>
<Caption>
                                                                                         Stock Vested on Dates Shown
           Option     Grant                                       Shares              ---------------------------------
            Plan       Date                                     Outstanding           3/8/2002   1/26/2003    1/26/2004
           ------     -----                                     -----------           --------   ---------    ---------
<S>                  <C>                                        <C>                   <C>        <C>          <C>
            1999     1/26/2001 Granted for year 2000               4,837                4,837
            1999     1/26/2001 Granted for year 2000               4,837                           4,837
            1999     1/26/2001 Granted for year 2000               4,838                                        4,838
                                                                  ------                -----      -----        -----

                                                                  14,512                4,837      4,837        4,838
                                                                  ======                =====      =====        =====
</Table>

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00036-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00036-of-00352.parquet"}]]