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                                                                   EXHIBIT 10.69


                              TERMINATION AGREEMENT
    
     THIS TERMINATION AGREEMENT, dated as of March 2, 1999 is made and entered
into by and between Texas Biotechnology Corporation, a Delaware corporation with
its principal office at 7000 Fannin, Suite 1920, Houston, Texas (the "Company"),
and Pamela M. Murphy ("Executive").
    
                                R E C I T A L S
    
     A. Company desires to enter into an agreement with Executive whereby
severance benefits will be paid to Executive on a change in control of the
Company and consequent actual or constructive termination of Executive's
employment.
    
     B. This Agreement sets forth the severance benefits which the Company
agrees that it will pay to the Executive if Executive's employment with the
Company terminates under one of the circumstances described herein following a
Change in Control of the Company.
    
     NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants contained herein, the parties hereto agree as follows:
    
     1. Term of Agreement. This Agreement shall be effective immediately on the
date hereof and shall continue in effect through December 31, 1999; provided,
however, that commencing on January 1, 2000 and each January 1 thereafter, the
term of this Agreement shall automatically be extended for one additional year
unless not later than September 30 of the preceding year, the Company shall have
given notice that it does not wish to extend this Agreement; provided, further,
that notwithstanding any such notice by the Company not to extend this Agreement
shall automatically be extended for 24 months beyond the term provided herein if
a Change in Control, as defined in Section 3 of this Agreement has occurred
during the term of this Agreement.
    
     2. Effect on Employment Rights. This Agreement is not part of any
employment agreement that the Company and Executive may have entered. Nothing in
this Agreement shall confer upon Executive any right to continue in the employ
of the Company or interfere with or restrict in any way the rights of the
Company, which are hereby expressly reserved, to terminate for any reason, with
or without cause.
    
     Executive agrees that, subject to the terms and conditions of this
Agreement, in the event of a potential change in control of the Company (as
defined below), Executive will remain in the employ of the Company during the
pendency of any such potential change in control and for a period of one year
after the occurrence of an actual Change in Control. For this purpose, a
"potential change in control of the Company" shall be deemed to have occurred if
(a) the Company enters into an agreement, the consummation of which would result
in the occurrence of a Change of Control, (b) any person (including the Company)
publicly announces an intention to take or consider taking action which if
consummated would constitute a Change in Control or (c) the Board of Directors
of the Company (the "Board") adopts a resolution to the effect that a potential
change in control of the Company has occurred.


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          3. Change in Control. For purposes of this Agreement, a "Change in
     Control" of the Company shall be deemed to have occurred if any of the
     events set forth in any one of the following paragraphs shall occur:
    
               (a) any "person" (as defined in section 3(a)(9) of the Securities
          Exchange Act of 1934, as amended (the "Exchange Act") and as such term
          is modified in sections 13(d) and 14(d) of the Exchange Act),
          excluding the Company or any of its subsidiaries, a trustee or any
          fiduciary holding securities under an employee benefit plan of the
          Company of any of its subsidiaries, an underwriter temporarily holding
          securities pursuant to an offering of such securities or a corporation
          owned, directly or indirectly, by stockholders of the Company in
          substantially the same proportions as their ownership of the Company,
          is or becomes the "beneficial owner" (as defined in Rule l3d-3 under
          the Exchange Act), directly or indirectly, of securities of the
          Company representing 30% or more of the combined voting power of the
          Company's then outstanding securities; or
    
               (b) during any period of not more than two consecutive years,
          individuals who at the beginning of such period constitute the Board
          and any new director (other than a director designated by a Person who
          has entered into an agreement with the Company to effect a transaction
          described in clause (a), (c) or (d) of this paragraph) whose election
          by the Board or nomination for election by the Company's stockholders
          was approved by a vote of at least two-thirds (2/3) of the directors
          then still in office who either were directors at the beginning of the
          period or whose election or nomination for election was previously so
          approved, cease for any reason to constitute a majority thereof; or
    
               (c) the shareholders of the Company approve a merger or
          consolidation of the Company with any other corporation, other than
          (i) a merger or consolidation which would result in the voting
          securities of the Company outstanding immediately prior thereto
          continuing to represent (either by remaining outstanding or by being
          converted into voting securities of the surviving entity), in
          combination with the ownership of any trustee or other fiduciary
          holder of securities under an employee benefit plan of the Company, at
          least 50% of the combined voting power of the voting securities of the
          Company or such surviving entity outstanding immediately after such
          merger or consolidation, or (ii) a merger or consolidation effected to
          implement a recapitalization of the Company (or similar transaction)
          in which no person acquires more than 50% of the combined voting power
          of the Company's then outstanding securities; or,
    
               (d) the shareholders of the Company approve a plan of complete
          liquidation of the Company or an agreement for the sale or disposition
          by the Company of all or substantially all of the Company's assets.

          Notwithstanding the foregoing, no Change in Control shall be deemed to
          have occurred if there is consummated any transaction or series of
          integrated transactions immediately following which, in the judgment
          of the Compensation Committee of the Board, the holder of the
          Company's Common Stock immediately prior to such transaction or series
          of transactions continue to have the same proportionate ownership in
          an entity which owns all or substantially all of the assets of the
          Company immediately prior to such transaction or series of
          transactions.

          4. Termination of Employment. Following a Change in Control. Executive
     shall be entitled to the benefits provided in Section 5 hereof upon the
     subsequent termination of


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     Executive's employment by the Company within two years after a Change in
     Control which occurs during the term of this Agreement, provided such
     termination is (a) by the Company other than for cause, as defined below,
     or (b) by Executive for Good Reason, as defined below. Executive shall not
     be entitled to the benefits of Section 5, any other provision hereof to the
     contrary notwithstanding, if Executive's employment terminates: (i)
     pursuant to Executive retiring at age 65, (ii) by reason of Executive's
     total and permanent disability, or (iii) by reason or Executive's death. As
     used herein, "total and permanent disability" means a condition which
     prevents Executive from performing to a significant degree the essential
     duties of his or her position and is expected to be of long-term duration
     or result in death. A determination of total and permanent disability must
     be based on competent medical evidence.
    
               (a) Cause.
    
               (i) Definition. Termination by the Company of Executive's
          employment for Cause shall mean termination upon Executive's willful
          engaging in misconduct which is demonstrably and materially injurious
          to the Company and its subsidiaries taken as a whole.  No act, or
          failure to act, on Executive's part shall be considered "willful"
          unless done, or omitted to be done, by Executive not in good faith and
          without reasonable belief that Executive's action or omission was in
          the best interest of the Company or its subsidiaries. Notwithstanding
          the foregoing, Executive shall not be deemed to have been terminated
          for Cause unless and until there shall have been delivered to
          Executive a copy of a resolution duly adopted by the affirmative vote
          of not less than three quarters of the entire membership of the Board
          at a meeting of the Board called and held for the purpose of making a
          determination of whether Cause for termination exists (after
          reasonable notice to Executive and an opportunity for Executive to be
          heard before the Board), finding that in the good faith opinion of the
          Board Executive was guilty of misconduct as set forth above in this
          subsection 4(a)(i) and specifying the particulars thereof in detail.
    
               (ii) Remedy by Executive. If the Company gives Executive a Notice
          of Termination which states that the basis for terminating Executive's
          employment is Cause, Executive shall have ten days after receipt of
          such Notice to remedy the facts and circumstances which provided
          Cause. The Board (or any duly authorized Committee thereof) shall make
          a good faith reasonable determination immediately after such ten-day
          period whether such facts and circumstances have been remedied and
          shall communicate such determination in writing to Executive. If the
          Board determines that an adequate remedy has not occurred, then the
          initial Notice of Termination shall remain in effect.
    
               (b) Good Reason. After a Change in Control, Executive may
          terminate employment with the Company at any time during the term of
          this Agreement if Executive has made a good faith reasonable
          determination that Good Reason exists for this termination.

                    (i) Definition. for purposes of this Agreement, "Good
               Reason" shall mean any of the following actions, if taken without
               the express consent of the Executive:

                    A. any material change by the Company in Executive's
               functions, duties, or responsibilities which change would cause
               Executive's position with the Company to become of less dignity,
               responsibility, importance, or scope from the position and
               attributes that applied to Executive immediately prior to the
               Change in Control;


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<PAGE>   4

    
                    B. any significant reduction in Executive's base salary,
               other than a reduction effected as part of an across-the-board
               reduction affecting all executive employees of the Company;
    
                    C. any material failure by the Company to comply with any of
               the provisions of this Agreement (or of any employment agreement
               between the parties);
    
                    D. the Company's requiring Executive to be based at any
               office or location more than 45 miles from the home at which the
               Executive resides on the date immediately preceding the Change in
               Control, except for travel reasonably required in the performance
               of Executive's responsibilities and commensurate with the amount
               of travel required of Executive prior to the Change in Control;
               or
    
                    E. any failure by the Company to obtain the express
               assumption of this Agreement by any successor or assign of the
               Company.
    
                    Executive's right to terminate employment for Good Reason
               pursuant to this subsection 4(b)(I) shall not be affected by
               Executive's incapacity due to physical or mental illness.
    
                    (ii) Remedy by Company. If Executive gives the Company a
               Notice of Termination which states that the basis for Executive's
               termination of employment is Good Reason, the Company shall have
               ten days after receipt of such Notice to remedy the facts and
               circumstances which provided Good Reason. Executive shall make a
               good faith reasonable determination immediately after such
               ten-day period whether such facts and circumstances have been
               remedied and shall communicate such determination in writing to
               the Company. If Executive determines that adequate remedy has not
               occurred, then the initial Notice of Termination shall remain in
               effect.
    
                    (iii) Determination by Executive Presumed Correct. Any
               determination by Executive pursuant to this Section 4(b) that
               Good Reason exists for Executive's termination of employment and
               that adequate remedy has not occurred shall be presumed correct
               and shall govern unless the party contesting the determination
               shows by a clear preponderance of the evidence that it was not a
               good faith reasonable determination.
    
                    (iv) Severance Payment Made Notwithstanding Dispute.
               Notwithstanding any dispute concerning whether Good Reason exists
               for termination of employment or whether adequate remedy has
               occurred, the Company shall immediately pay to Executive, as
               specified in Section 5, any amounts otherwise due under this
               Agreement. Executive may be required to repay such amounts to the
               Company if any such dispute is finally determined adversely to
               Executive.
    

               (c) Notice of Termination. Any termination of Executive's
          employment by the Company or by Executive hereunder shall be
          communicated by a Notice of Termination to the other party hereto. For
          purposes of this Agreement, a "Notice of Termination" shall mean a
          written notice which shall indicate the specific termination
          provisions in this Agreement relied upon and which sets forth (i) in
          reasonable detail the facts and


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          circumstances claimed to provide a basis for termination of
          Executive's employment under the provision so indicated and (ii) the
          date of Executive's termination of employment, which shall be no
          earlier than 10 days after such Notice is received by the other party.
          Any purported termination of the Executive's employment by the Company
          which is not effected pursuant to a Notice of Termination satisfying
          the requirements of this Agreement shall not be effective. In the case
          of a termination for Cause, the Notice of Termination shall also
          satisfy the requirements set forth in Section 4(a)(i).
    
          5. Severance Payment Upon Termination of Employment. If Executive's
     employment with the Company is terminated during the term of this Agreement
     and after a Change in Control (a) by the Company other than for Cause, or
     (b) by Executive for Good Reason, then Executive shall be entitled to the
     following:
    
          (a) Lump-Sum Severance Payment. In lieu of any further salary payments
          to the Executive for periods subsequent to the Date of Termination,
          the Company shall pay to the Executive a lump sum severance payment,
          in cash, equal to one and one half (1.5) (or, if less, the number of
          years, including fractions, from the Date of Termination until the
          Executive would have reached age sixty-five (65)) times the sum of (a)
          the Executive's Annual Base Salary in effect on date of termination
          and (b) the Executive's most recent Annual Bonus. If the most recent
          Annual Bonus was a stock option or a stock grant, the value of the
          bonus will be deemed to be the number of option shares times the
          closing price of the Company's Common Stock for the 20 trading days
          prior to Termination.
    
          (b) Continued Benefits. For a eighteen (18) month period (or, if less,
          the number of months from the Date of Termination until the Executive
          would have reached age sixty-five (65)) after the Date of Termination,
          the Company shall provide the Executive with life insurance, health,
          disability and other welfare benefits ("Welfare Benefits")
          substantially similar in all respects to those which the Executive is
          receiving immediately prior to the Notice of Termination (without
          giving effect to any reduction in such benefits subsequent to the
          Potential Change in Control preceding the Change in Control or the
          Change in Control which reduction constitutes or may constitute Good
          Reason). Benefits otherwise receivable by an Executive pursuant to
          this Section shall be reduced to the extent substantially similar
          benefits are actually received by or made available to the Executive
          by any other employer during the same time period for which such
          benefits would be provided pursuant to this Section at a cost to the
          Executive that is commensurate with the cost incurred by the Executive
          immediately prior to the Executive's Date of Termination (without
          giving effect to any increase in costs paid by the Executive after the
          Potential Change in Control preceding the Change in Control or the
          Change in Control which constitutes or may constitute Good Reason);
          provided, however, that if the Executive becomes employed by a new
          employer which maintains a medical plan that either (i) does not cover
          the Executive or a family member or dependent with respect to a
          preexisting condition which was covered under the applicable Company
          medical plan, or (ii) does not cover the Executive or a family member
          or dependent for a designated waiting period, the Executive's coverage
          under the applicable Company medical plan shall continue (but shall be
          limited in the event of noncoverage due to a preexisting condition, to
          such preexisting condition) until the earlier of the end of the
          applicable period of noncoverage under the new employer's plan or the
          third anniversary of the Executive's Date of Termination. The
          Executive agrees to report to the Company any coverage and benefits
          actually received by the Executive or made available to the Executive
          from such other employer(s). The Executive shall be entitled to elect
          to change his level of coverage and/or his choice of
    

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          coverage options (such as Executive only or family medical coverage)
          with respect to the Welfare Benefits to be provided by the Company to
          the Executive to the same extent that actively employed senior
          executives of the Company are permitted to make such changes,
          provided, however, that in the event of any such changes the Executive
          shall pay the amount of any cost increase that would actually be paid
          by an actively employed executive of the Company by reason of making
          the same change in his level of coverage or coverage options.
    
               (c) Gross-Up Payment. In the event that the Executive becomes
          entitled to the Severance Benefits or any other benefits or payments
          under this Agreement (other than pursuant to this Section) by reason
          of the accelerated vesting of stock options thereunder (together, the
          "Total Benefits"), and in the event that any of the Total Benefits
          will be subject to the Excise Tax, the Company shall pay to the
          Executive an additional amount (the "Gross-Up Payment") such that the
          net amount retained by the Executive, after deduction of any Excise
          Tax on the Total Benefits and any federal, state and local income tax,
          Excise Tax and FICA and Medicare withholding taxes upon the payment
          provided for by this Section, shall be equal to the Total Benefits.
    
               For purposes of determining whether any of the Total Benefits
          will be subject to the Excise Tax and the amount of such Excise Tax,
          (i) any other payments or benefits received or to be received by the
          Executive in connection with a Change in Control or the Executive's
          termination of employment (whether pursuant to the terms of this
          Agreement or any other agreement, plan or arrangement with the
          Company, any Person whose actions result in a Change in Control or any
          Person affiliated with the Company or such Person) shall be treated as
          "parachute payments" within the meaning of Section 280G(b)(2) of the
          Code, and all "excess parachute payments" within the meaning of
          Section 280G(b)(1) shall be treated as subject to the Excise Tax,
          unless in the opinion of tax counsel ("Tax Counsel") selected by the
          Company's independent auditors and acceptable to the Executive, such
          other payments or benefits (in whole or in part) do not constitute
          parachute payments, or such excess parachute payments (in whole or in
          part) represent reasonable compensation for services actually rendered
          within the meaning of Section 280G(b)(4) of the Code in excess of the
          Base Amount, or are otherwise not subject to the Excise Tax, (ii) the
          amount of the Total Benefits which shall be treated as subject to the
          Excise Tax shall be equal to the lesser of (A) the total amount of the
          Total Benefits reduced by the amount of such Total Benefits that in
          the opinion of Tax Counsel are not parachute payments, or (B) the
          amount of excess parachute payments within the meaning of Section
          280G(b)(1) (after applying clause (i), above), and (iii) the value of
          any non-cash benefits or any deferred payment or benefit shall be
          determined by the Company's independent auditors in accordance with
          the principles of sections 280G(d)(3) and (4) of the Code. For
          purposes of determining the amount of the Gross-Up Payment, the
          Executive shall be deemed to pay federal income taxes at the highest
          marginal rate of federal income taxation in the calendar year in which
          the Gross-Up Payment is to be made and state and local income taxes at
          the highest marginal rate of taxation in the state and locality of the
          Executive's residence on the Date of Termination, net of the reduction
          in federal income taxes which could be obtained from deduction of such
          state and local taxes (calculated by assuming that any reduction under
          Section 68 of the Code in the amount of itemized deductions allowable
          to the Executive applies first to reduce the amount of such state and
          local income taxes that would otherwise be deductible by the
          Executive).



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               In the event that the Excise Tax is subsequently determined to be
          less than the amount taken into account hereunder at the time of
          termination of the Executive's employment, the Executive shall repay
          to the Company, at the time that the amount of such reduction in
          Excise Tax is finally determined, the portion of the Gross-Up Payment
          attributable to such reduction (plus that portion of the Gross-Up
          Payment attributable to the Excise Tax, federal, state and local
          income taxes and FICA and Medicare withholding taxes imposed on the
          portion of the Gross-Up Payment being repaid by the Executive to the
          extent that such repayment results in a reduction in Excise Tax, FICA
          and Medicare withholding taxes and/or federal, state or local income
          taxes) plus interest on the amount of such repayment at the rate
          provided in Section 1274(b)(2)(B) of the Code. In the event that the
          Excise Tax is determined to exceed the amount taken into account
          hereunder at the time of the termination of the Executive's employment
          (including by reason of any payment the existence or amount of which
          cannot be determined at the time of the Gross-Up Payment), the Company
          shall make an additional Gross-Up Payment, determined as previously
          described, to the Executive in respect of such excess (plus any
          interest, penalties or additions payable by the Executive with respect
          to such excess) at the time that the amount of such excess is finally
          determined.
    
               (D) Timing of Payments. The payments provided for in Sections
          5(a) and 5(c) shall be made not later than the fifth (5th) day
          following the Date of Termination; provided, however, that if the
          amounts of such payments cannot be finally determined on or before
          such day, the Company shall pay to the Executive on such day an
          estimate, as determined in good faith by the Company, of the minimum
          amount of such payments and shall pay the remainder of such payments
          (together with interest at the rate provided in Section 1274(b)(2)(B)
          of the Code from the fifth (5th) day following the Date of Termination
          to the payment of such remainder) as soon as the amount thereof can be
          determined but in no event later than the thirtieth (30th) day after
          the Date of Termination. In the event that the amount of the estimated
          payments exceeds the amount subsequently determined to have been due,
          such excess shall constitute a loan by the Company to the Executive,
          payable on the fifth (5th) business day after demand by the Company
          (together with interest at the rate provided in Section 1274(b)(2)(B)
          of the Code from the fifth (5th) day following the Date of Termination
          to the repayment of such excess).
    
               6(D) Reimbursement of Legal Costs. The Company shall pay to the
          Executive all legal fees and expenses incurred by the Executive as a
          result of a termination which entities the Executive to any payments
          under this Agreement including all such fees and expenses, if any,
          incurred in contesting or disputing any Notice of Intent to Terminate
          under Section 4(a) hereof or in seeking to obtain or enforce any
          right or benefit provided by this Agreement or in connection with any
          tax audit or proceeding to the extent attributable to the application
          of Section 4999 of the Code to any payment or benefit provide
          hereunder. Such payments shall be made within five (5) business days
          after delivery of the Executive's respective written requests for
          payment accompanied by such evidence of fees and expenses incurred as
          the Company reasonably may require.
    
          7. Damages. Executive shall not be required to mitigate damages with
     respect to the amount of any payment provided under this Agreement by
     seeking other employment or otherwise, nor shall the amount of any payment
     provided under this Agreement be reduced by retirement benefits, deferred
     compensation or any compensation earned by Executive as a result of
     employment by another employer.
    


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          8. Successor to Company. The Company shall require any successor or
     assign (whether direct or indirect, by purchase, merger, consolidation or
     otherwise) to all or substantially all of the business and/or assets of the
     Company, by agreement in form and substance satisfactory to Executive,
     expressly, absolutely and unconditionally 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 it if no such succession or assignment had
     taken place. As used in this Agreement, "Company" shall mean the Company as
     hereinbefore defined and any successor or assign to its business and/or
     assets as aforesaid which executes and delivers the agreement provided for
     in this section or which otherwise becomes bound by all the terms and
     provisions of this Agreement by operation of law.
    
          9. Heirs of Executive. This Agreement shall inure to the benefit of
     and be enforceable by Executive's personal and legal representatives,
     executors, administrators, successors, heirs, distributes, devisees and
     legatees. If Executive should die while any amounts are still payable to
     Executive hereunder, all such amounts, unless otherwise provided herein,
     shall be paid in accordance with the terms of this Agreement to Executive's
     devisee, legatee, or other designee or, if there be so such designee, to
     Executive's estate.
    
          10. Arbitration. Any dispute, controversy or claim arising under or in
     connection with this Agreement, or the breach hereof, shall be settled
     exclusively by arbitration in accordance with the Rules of the American
     Arbitration Association then in effect. Judgment upon the award rendered by
     the arbitrator(s) may be entered in any court of competent jurisdiction.
     Any arbitration held pursuant to this section in connection with
     Executive's termination of employment shall take place in Houston, Texas at
     the earliest possible date. If any proceeding is necessary to enforce or
     interpret the terms of this Agreement, or to recover damages for breach
     thereof, the prevailing party shall be entitled to reasonable attorneys
     fees and necessary costs and disbursements, not to exceed in the aggregate
     one percent (1%) of the net worth of the other party, in addition to any
     other relief to which he or it may be entitled.
    
          11. Notice. For purposes of this Agreement, notices and all other
     communications provided for in this Agreement shall be in writing and shall
     be deemed to have been duly given when delivered by messenger or in person,
     or when mailed by United States registered mail, return receipt requested,
     postage prepaid, as follows:
    
          If to the Company:    Texas Biotechnology Corporation
                                7000 Fannin, Suite 1920
                                Houston, Texas 77030
                                Attention: President
    
          If to the Executive:  Pamela M. Murphy
                                c/o Texas Biotechnology Corporation
                                7000 Fannin, Suite 1920
                                Houston, Texas 77030
    
     or such other address as either party may have furnished to the other in
     writing in accordance herewith, except that notices of change of address
     shall be effective only upon receipt.
    

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          12. General Provisions.
    
               (a) Executive's rights and obligations under this Agreement shall
     not be transferable by assignment or otherwise, nor shall Executive's
     rights be subject to encumbrance or subject to the claims of the Company's
     creditors. Nothing in this Agreement shall prevent the consolidation of the
     Company with, or its merger into, any other corporation, or the sale by the
     Company of all or substantially all of its properties or assets; and this
     Agreement shall inure to the benefit of, be binding upon and be enforceable
     by, any successor surviving or resulting corporation, or other entity to
     which such assets shall be transferred. This Agreement shall not be
     terminated by the voluntary or involuntary dissolution of the Company.
    
               (b) This Agreement and any Employment Agreement with Executive
     plus terms of any stock option plans or grants constitutes the entire
     agreement between the parties hereto in respect to the rights and
     obligations of the parties following a Change in Control. This Agreement
     supersedes and replaces all prior oral and written agreements,
     understandings, commitments, and practices between the parties (whether or
     not fully performed by Executive prior to the date hereof), which shall be
     of no further force or effect.
    
               (c) The provisions of this Agreement shall be regarded as 
     divisible, and if any of said provisions or any part thereof are declared
     invalid or unenforceable by a court of competent jurisdiction, the validity
     and enforceability of the remainder of such provisions or parts thereof and
     the applicability thereof shall not be affected thereby.
    
               (d) This Agreement may not be amended or modified except by a 
     written instrument executed by the Company and Executive.
    
               (e) This Agreement and the rights and obligations hereunder shall
     be governed by and construed in accordance with the laws of the State of
     Texas.
    
               IN WITNESS WHEREOF, the parties have executed this Agreement as
     of the date first above written.



                                              TEXAS BIOTECHNOLOGY CORPORATION
                                              A Delaware Corporation
     
                                              By  /s/ DAVID B. MCWILLIAMS
                                                 -------------------------------
       Attest:                                    David B. McWilliams
                                                  President and CEO

    By /s/ STEPHEN L. MUELLER
       ------------------------------------
       By the authority of the Compensation
       Committee of the Board of Directors of
       Texas Biotechnology Corporation on
       March 23, 1999.                            /s/ PAMELA M. MURPHY
                                                  ------------------------------
                                                            Executive
   


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