EXHIBIT 1.1



                          ENCYSIVE PHARMACEUTICALS INC.

                                  COMMON STOCK

                             UNDERWRITING AGREEMENT



                                                              September 8, 2004

WACHOVIA CAPITAL MARKETS, LLC
301 South College Street, NC0610
Charlotte, North Carolina 28288

Dear Sirs:

1. INTRODUCTORY. Encysive Pharmaceuticals Inc., a Delaware corporation (the
"Company"), proposes to sell, pursuant to the terms of this Agreement, to
Wachovia Capital Markets, LLC ("Wachovia" or the "Underwriter"), an aggregate of
4,000,000 shares of common stock, $.005 par value (the "Common Stock"), of the
Company. The aggregate of 4,000,000 shares so proposed to be sold is hereinafter
referred to as the "Firm Stock". The Company also proposes to sell to the
Underwriter, upon the terms and conditions set forth in Section 3 hereof, up to
an additional 600,000 shares of Common Stock (the "Optional Stock"). The Firm
Stock and the Optional Stock are hereinafter collectively referred to as the
"Stock".

2. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company represents and
warrants to, and agrees with, the Underwriter that:

         (a) The Company meets the requirements for use of Form S-3 under the
         Securities Act of 1933, as amended (the "Securities Act") and the rules
         and regulations of the Commission (the "Rules and Regulations")
         thereunder. A registration statement on Form S-3 (File No. 333-116193)
         (including all pre-effective amendments thereto, the "Initial
         Registration Statement") in respect of the Stock has been filed with
         the Securities and Exchange Commission (the "Commission") pursuant to
         Rule 415 under the Securities Act; the Initial Registration Statement
         and any post-effective amendment thereto, each in the form heretofore
         delivered to you, and, excluding exhibits thereto but including all
         documents incorporated by reference in the prospectus contained
         therein, have been declared effective by the Commission in such form
         and meet the requirements of the Securities Act and the Rules and
         Regulations; other than a registration statement, if any, increasing
         the size of the offering (a "Rule 462(b) Registration Statement"),
         filed pursuant to Rule 462(b) under the Securities Act and the Rules
         and Regulations, which became effective upon filing, and any Form 8-K
         to be filed under the Securities Act regarding the execution of this
         Agreement and related matters, no other document with respect to the
         Initial Registration Statement or document incorporated by reference
         therein has heretofore been filed with the Commission; and no stop
         order suspending the effectiveness of the Initial Registration
         Statement, any post-effective amendment thereto or the Rule 462(b)
         Registration Statement, if any, has been issued and no proceeding for
         that purpose has been initiated or, to the Company's knowledge,
         threatened by the Commission (any preliminary prospectus included in
         the Initial Registration Statement or filed with the Commission
         pursuant to Rule 424(a) of the Rules and Regulations, is hereinafter
         called a "Preliminary Prospectus"); the various parts of the Initial
         Registration Statement and the Rule 462(b) Registration Statement, if
         any, including all exhibits thereto and including (i) the information
         contained in the form of final prospectus filed with the Commission
         pursuant to Rule 424(b) under the Securities Act and deemed by virtue
         of Rule 430A under the Securities Act to be part of the Initial
         Registration

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         Statement at the time it was declared effective and (ii) the documents
         incorporated by reference in the prospectus contained in the Initial
         Registration Statement at the time such part of the Initial
         Registration Statement became effective, each as amended at the time
         such part of the Initial Registration Statement became effective or
         such part of the Rule 462(b) Registration Statement, if any, became or
         hereafter becomes effective, are hereinafter collectively called the
         "Registration Statements"; and such final prospectus, in the form first
         filed pursuant to Rule 424(b) under the Securities Act, is hereinafter
         called the "Prospectus"; and any reference herein to any Preliminary
         Prospectus or the Prospectus shall be deemed to refer to and include
         the documents incorporated by reference therein pursuant to Item 12 of
         Form S-3 under the Securities Act, as of the date of such Preliminary
         Prospectus or Prospectus, as the case may be; any reference to any
         amendment or supplement to any Preliminary Prospectus or the Prospectus
         shall be deemed to refer to and include any documents filed after the
         date of such Preliminary Prospectus or Prospectus, as the case may be,
         under the Securities Exchange Act of 1934, as amended (the "Exchange
         Act"), and incorporated by reference in such Preliminary Prospectus or
         Prospectus, as the case may be; and any reference to any amendment to
         the Registration Statements shall be deemed to refer to and include any
         annual report of the Company filed pursuant to Section 13(a) or 15(d)
         of the Exchange Act after the effective date of the Initial
         Registration Statement that is incorporated by reference in the
         Registration Statements. No document has been or will be prepared or
         distributed in reliance on Rule 434 under the Securities Act. No order
         preventing or suspending the use of any Preliminary Prospectus has been
         issued by the Commission.

         (b) The Registration Statement conforms (and the Rule 462(b)
         Registration Statement, if any, the Prospectus and any amendments or
         supplements to either of the Registration Statements or the Prospectus,
         when they become effective or are filed with the Commission, as the
         case may be, will conform) in all material respects to the requirements
         of the Securities Act and the Rules and Regulations and do not and will
         not, as of the applicable effective date (as to the Registration
         Statements and any amendment thereto) and as of the applicable filing
         date (as to the Prospectus and any amendment or supplement thereto) and
         the First Closing Date (as defined below) and the Option Closing Date
         (as defined below) contain any untrue statement of a material fact or
         omit to state any material fact required to be stated therein or
         necessary to make the statements therein not misleading; provided,
         however, that the foregoing representations and warranties shall not
         apply to information contained in or omitted from the Registration
         Statements or the Prospectus or any such amendment or supplement
         thereto in reliance upon, and in conformity with, written information
         furnished to the Company by or on behalf of the Underwriter
         specifically for inclusion therein, which information the parties
         hereto agree is limited to the Underwriter's Information (as defined in
         Section 16).

         (c) The documents incorporated by reference in the Prospectus, when
         they became effective or were filed with the Commission, as the case
         may be, conformed in all material respects to the requirements of the
         Securities Act or the Exchange Act, as applicable, and the Rules and
         Regulations or the rules and regulations of the Commission under the
         Exchange Act, as applicable, and none of such documents contained any
         untrue statement of a material fact or omitted to state any material
         fact required to be stated therein or necessary to make the statements
         therein not misleading; and any further documents so filed and
         incorporated by reference in the Prospectus, when such documents become
         effective or are filed with Commission, as the case may be, will
         conform in all material respects to the requirements of the Securities
         Act or the Exchange Act, as applicable, and the Rules and Regulations
         or the rules and regulations of the Commission under the Exchange Act,
         as applicable, and will not contain any untrue statement of a material
         fact or omit to state any material fact required to be stated therein
         or necessary to make the statements therein not misleading.

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         (d) The Company and each of its subsidiaries (as defined in Section 14)
         have been duly organized and are validly existing as corporations or
         other legal entities in good standing (or the foreign equivalent
         thereof, if any) under the laws of their respective jurisdictions of
         organization, are duly qualified to do business and are in good
         standing as foreign corporations or other legal entities in each
         jurisdiction in which their respective ownership or lease of property
         or the conduct of their respective businesses requires such
         qualification, and have all power and authority necessary to own or
         hold their respective properties and to conduct the businesses in which
         they are engaged, except where the failure to so qualify or have such
         power or authority would not have, singularly or in the aggregate, a
         material adverse effect on the condition (financial or otherwise),
         results of operations, business or prospects of the Company and its
         subsidiaries taken as a whole (a "Material Adverse Effect"). The
         Company owns or controls, directly or indirectly, only the following
         corporations, partnerships, limited liability partnerships, limited
         liability companies, associations or other entities: (i)
         ImmunoPharmaceutics, Inc., a California corporation and wholly owned
         subsidiary of the Company; (ii) EP-ET, LLC, a Delaware limited
         liability company and wholly owned subsidiary of the Company; (iii)
         Encysive, L.P., a Delaware limited partnership, of which the Company is
         the sole limited partner and EP-ET, LLC is the sole general partner;
         (iv) Revotar Biopharmaceuticals, AG, a German corporation and
         majority-owned subsidiary of the Company; and (v) Encysive (UK)
         Limited, a United Kingdom private limited company and wholly owned
         subsidiary of the Company.

         (e) This Agreement has been duly authorized, executed and delivered by
         the Company.

         (f) The Stock to be issued and sold by the Company to the Underwriter
         hereunder has been duly and validly authorized and, when issued and
         delivered against payment therefor as provided herein, will be duly and
         validly issued, fully paid and nonassessable and free of any preemptive
         or similar rights and will conform to the description thereof contained
         in the Prospectus.

         (g) The Company has an authorized capitalization as set forth in the
         Prospectus, and all of the issued shares of capital stock of the
         Company, have been duly and validly authorized and issued, are fully
         paid and non-assessable, have been issued in compliance with federal
         and state securities laws, and conform to the description thereof
         contained in the Prospectus. None of the outstanding shares of Common
         Stock was issued in violation of any preemptive rights, rights of first
         refusal or other similar rights to subscribe for or purchase securities
         of the Company. There are no authorized or outstanding options,
         warrants, preemptive rights, rights of first refusal or other rights to
         purchase, or equity or debt securities convertible into or exchangeable
         or exercisable for, any capital stock of the Company or any of its
         subsidiaries other than those accurately described in the Prospectus.
         The description of the Company's stock option, stock bonus and other
         stock plans or arrangements, and the options or other rights granted
         thereunder, as described in the Prospectus accurately and fairly
         present the information required to be shown with respect to such
         plans, arrangements, options and rights.

         (h) All the outstanding shares of capital stock of each subsidiary of
         the Company have been duly authorized and validly issued, are fully
         paid and nonassessable and, except to the extent set forth in the
         Prospectus, are owned by the Company directly or indirectly through one
         or more wholly-owned subsidiaries, free and clear of any claim, lien,
         encumbrance, security interest, restriction upon voting or transfer or
         any other claim of any third party.

         (i) The execution, delivery and performance of this Agreement by the
         Company and the consummation of the transactions contemplated hereby
         will not conflict with or result in a breach or violation of any of the
         terms or provisions of, or constitute (with or without notice or lapse
         of time or both) a default under, any indenture, mortgage, deed of
         trust, loan agreement or other agreement or instrument to which the
         Company or any of its subsidiaries is a party or by which

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         the Company or any of its subsidiaries is bound or to which any of the
         property or assets of the Company or any of its subsidiaries is
         subject, nor will such actions result in any violation of the
         provisions of the charter or by-laws (or analogous governing
         instruments, as applicable) of the Company or any of its subsidiaries
         or any statute or any order, rule or regulation of any court or
         governmental agency or body having jurisdiction over the Company or any
         of its subsidiaries or any of their properties or assets.

         (j) Except for the registration of the Stock under the Securities Act
         and such consents, approvals, authorizations, registrations or
         qualifications as may be required under the Exchange Act, applicable
         state securities laws and the Nasdaq National Market ("Nasdaq") in
         connection with the purchase and distribution of the Stock by the
         Underwriter, no consent, approval, authorization or order of, or filing
         or registration with, any court or governmental agency or body is
         required for the execution, delivery and performance of this Agreement
         by the Company and the consummation of the transactions contemplated
         hereby.

         (k) KPMG LLP, who has expressed its opinions on the audited financial
         statements and related schedules included or incorporated by reference
         in the Registration Statements and the Prospectus are independent
         public accountants as required by the Securities Act and the Rules and
         Regulations.

         (l) The financial statements, together with the related notes and
         schedules, included or incorporated by reference in the Prospectus and
         in each Registration Statement fairly present the financial position
         and the results of operations and changes in financial position of the
         Company and its consolidated subsidiaries and other consolidated
         entities at the respective dates or for the respective periods therein
         specified, except as noted therein and except, in the case of unaudited
         financial statements, for normal year-end audit adjustments. Such
         statements and related notes and schedules have been prepared in
         accordance with generally accepted accounting principles recognized in
         the United States ("GAAP") applied on a consistent basis except as may
         be set forth in the Prospectus. The financial statements, together with
         the related notes and schedules, included in the Prospectus comply in
         all material respects with the Securities Act and the Rules and
         Regulations thereunder. No other financial statements or supporting
         schedules or exhibits are required by the Securities Act or the Rules
         and Regulations thereunder to be included in the Prospectus.

         (m) Neither the Company nor any of its subsidiaries has sustained,
         since the date of the latest audited financial statements included or
         incorporated by reference in the Prospectus, any material loss or
         interference with its business from fire, explosion, flood or other
         calamity, whether or not covered by insurance, or from any labor
         dispute or court or governmental action, order or decree, otherwise
         than as set forth or contemplated in the Prospectus; and, since such
         date, there has not been any change in the capital stock or long-term
         debt of the Company or any of its subsidiaries or any material adverse
         change, or any development involving a prospective material adverse
         change, in or affecting the business, general affairs, management,
         financial position, stockholders' equity or results of operations of
         the Company and its subsidiaries taken as a whole, otherwise than as
         set forth or contemplated in the Prospectus.

         (n) Except as set forth in the Prospectus and except for the
         modification of intellectual property rights pursuant to proceedings
         involving the processing and examination of patent and trademark
         applications and patents before governmental agencies or bodies, there
         is no legal or governmental proceeding pending to which the Company or
         any of its subsidiaries is a party or of which any property or assets
         of the Company or any of its subsidiaries is the subject which is
         required to be described in the Registration Statement or the
         Prospectus and is not described therein, or which, singularly or in the
         aggregate, if determined adversely to the Company or any

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         of its subsidiaries, might have a Material Adverse Effect or would
         prevent or adversely affect the ability of the Company to perform its
         obligations under this Agreement; and to the best of the Company's
         knowledge, no such proceedings are threatened or contemplated by
         governmental authorities or threatened by others. The Company and its
         subsidiaries are in compliance with all applicable federal, state,
         local and foreign laws, regulations, orders and decrees governing their
         business as prescribed by the United States Food and Drug
         Administration (the "FDA"), or any other federal, state or foreign
         agencies or bodies, including those bodies and agencies engaged in the
         regulation of pharmaceuticals or biohazardous substances or materials,
         except where noncompliance would not, singly or in the aggregate, have
         a Material Adverse Effect. All preclinical and clinical studies
         undertaken to support approval of products for commercialization have
         been conducted in compliance with all applicable federal, state or
         foreign laws, rules, orders or regulations, including current Good
         Laboratory and Good Clinical Practices in all material respects. No
         filing or submission to the FDA or any other federal, state or foreign
         regulatory body, that is intended to be the basis for any approval,
         contains any material omission or material false information.

         (o) Neither the Company nor any of its subsidiaries (i) is in violation
         of its charter or by-laws (or analogous governing instrument, as
         applicable), (ii) is in default in any respect, and no event has
         occurred which, with notice or lapse of time or both, would constitute
         such a default, in the due performance or observance of any term,
         covenant or condition contained in any indenture, mortgage, deed of
         trust, loan agreement or other agreement or instrument to which it is a
         party or by which it is bound or to which any of its property or assets
         is subject or (iii) is in violation in any respect of any law,
         ordinance, governmental rule, regulation or court decree to which it or
         its property or assets may be subject except, in the case of clauses
         (ii) and (iii), any violations or defaults which, singularly or in the
         aggregate, would not have a Material Adverse Effect.

         (p) The Company and each of its subsidiaries possess all licenses,
         certificates, authorizations and permits issued by, and have made all
         declarations and filings with, the appropriate local, state, federal or
         foreign regulatory agencies or bodies which are necessary or desirable
         for the ownership of their respective properties or the conduct of
         their respective businesses as described in the Prospectus, including
         without limitation all such licenses, certificates, authorizations and
         permits required by the FDA or any other federal, state or foreign
         agencies or bodies engaged in the regulation of pharmaceuticals or
         biohazardous materials, except where any failures to possess or make
         the same, singularly or in the aggregate, would not have a Material
         Adverse Effect; all of such licenses, certificates, authorizations and
         permits are valid and in full force and effect, except where the
         invalidity of such licenses, certificates, authorizations and permits
         or the failure of such licenses, certificates, authorizations and
         permits to be in full force and effect would not, singularly or in the
         aggregate, have a Material Adverse Effect; all such licenses,
         certificates, authorizations and permits are free and clear of any
         restrictions or conditions that are in addition to, or materially
         different from, those normally applicable to similar licenses,
         certificates, authorizations and permits; and neither the Company nor
         any of its subsidiaries has received notification of any revocation or
         modification of any such license, certificate, authorization or permit
         and has no reason to believe that any such license, certificate,
         authorization or permit will not be renewed.

         (q) Neither the Company nor any of its subsidiaries is or, after giving
         effect to the offering of the Stock and the application of the proceeds
         thereof as described in the Prospectus will become an "investment
         company" within the meaning of the Investment Company Act of 1940, as
         amended and the rules and regulations of the Commission thereunder.

         (r) The Company has not taken and will not take, directly or
         indirectly, any action designed or intended to stabilize or manipulate
         the price of any security of the Company, or which caused


                                                                               6

         or resulted in, or which might in the future reasonably be expected to
         cause or result in, stabilization or manipulation of the price of any
         security of the Company.

         (s) The Company and its subsidiaries own or possess the right to use
         all patents, trademarks, trademark registrations, service marks,
         service mark registrations, trade names, copyrights, licenses,
         inventions, trade secrets, know-how and other intellectual property
         rights which are necessary for the conduct of their respective
         businesses as described in the Prospectus, and the Company is not aware
         of any claim to the contrary or any challenge by any other person to
         the rights of the Company and its subsidiaries with respect to the
         foregoing. The Company and its subsidiaries have made all declarations
         and filings, including, without limitation, assignments and payment of
         fees, with the appropriate local, state or federal regulatory bodies
         which are necessary to maintain in full force and effect ownership and
         possession of the intellectual property rights of the Company and its
         subsidiaries, except where such failure to make the same would not,
         singularly or in the aggregate, have a Material Adverse Effect, and,
         except for the modification of intellectual property rights pursuant to
         proceedings involving the processing and examination of patent and
         trademark applications and patents before governmental agencies or
         bodies, the Company has not received written notification of any
         revocation or modification of any intellectual property right, and has
         no reason to believe that any renewable intellectual property right
         will not be renewed, other than any revocation, modification or failure
         to renew that would not, singularly or in the aggregate, have a
         Material Adverse Effect. The Company's and its subsidiaries' businesses
         as now conducted and as currently proposed to be conducted do not and
         will not infringe or conflict with any patents, trademarks, service
         marks, trade names, copyrights, trade secrets, licenses, know-how or
         other intellectual property right or franchise right of any person.
         Except as described in the Prospectus, no claim has been made against
         the Company or any of its subsidiaries alleging the infringement by the
         Company or any of its subsidiaries of any patent, trademark, service
         mark, trade name, copyright, trade secret, license, know-how or other
         intellectual property right or franchise right of any person.

         (t) Except as disclosed in the Prospectus, the Company and each of its
         subsidiaries have good and marketable title in fee simple to, or have
         valid rights to lease or otherwise use, all items of real or personal
         property which are material to the business of the Company and its
         subsidiaries taken as a whole, in each case free and clear of all
         liens, encumbrances, security interests, claims and defects that may
         result in a Material Adverse Effect.

         (u) No labor disturbance by the employees of the Company or any of its
         subsidiaries exists or, to the best of the Company's knowledge, is
         imminent which might be expected to, singularly or in the aggregate,
         have a Material Adverse Effect. The Company is not aware that any key
         employee or significant group of employees of the Company or any
         subsidiary plans to terminate employment with the Company or any such
         subsidiary.

         (v) No "prohibited transaction" (as defined in Section 406 of the
         Employee Retirement Income Security Act of 1974, as amended, including
         the regulations and published interpretations thereunder ("ERISA"), or
         Section 4975 of the Internal Revenue Code of 1986, as amended from time
         to time (the "Code")) or "accumulated funding deficiency" (as defined
         in Section 302 of ERISA) or any of the events set forth in Section
         4043(b) of ERISA (other than events with respect to which the 30-day
         notice requirement under Section 4043 of ERISA has been waived) has
         occurred with respect to any employee benefit plan which could,
         singularly or in the aggregate, have a Material Adverse Effect; each
         employee benefit plan of the Company and its subsidiaries is in
         compliance in all material respects with applicable law, including
         ERISA and the Code; the Company has not incurred and does not expect to
         incur liability under Title IV of ERISA with respect to the termination
         of, or withdrawal from, any "pension plan"; and each "pension plan" (as
         defined in ERISA) for which the Company would have any liability that
         is

                                                                               7

         intended to be qualified under Section 401(a) of the Code is so
         qualified in all material respects and nothing has occurred, whether by
         action or by failure to act, which could cause the loss of such
         qualification.

         (w) There has been no storage, generation, transportation, handling,
         treatment, disposal, discharge, emission, or other release of any kind
         of toxic or other wastes or other hazardous substances by, due to, or
         caused by the Company or any of its subsidiaries (or, to the best of
         the Company's knowledge, any other entity for whose acts or omissions
         the Company or any of its subsidiaries is or may be liable) upon any of
         the property now or previously owned or leased by the Company or any of
         its subsidiaries, or upon any other property, in violation of any
         statute or any ordinance, rule, regulation, order, judgment, decree or
         permit or which would, under any statute or any ordinance, rule
         (including rule of common law), regulation, order, judgment, decree or
         permit, give rise to any liability, except for any violation or
         liability which would not have, singularly or in the aggregate with all
         such violations and liabilities, a Material Adverse Effect; there has
         been no disposal, discharge, emission or other release of any kind onto
         such property or into the environment surrounding such property of any
         toxic or other wastes or other hazardous substances with respect to
         which the Company or any of its subsidiaries have knowledge, except for
         any such disposal, discharge, emission, or other release of any kind
         which would not have, singularly or in the aggregate with all such
         discharges and other releases, a Material Adverse Effect.

         (x) The Company and its subsidiaries each (i) have filed all necessary
         federal, state and foreign income and franchise tax returns, all of
         which, when filed, were true, complete and correct in all material
         respects, (ii) have paid all federal state, local and foreign taxes due
         and payable for which it is liable, and (iii) do not have any tax
         deficiency or claims outstanding or assessed or, to the best of the
         Company's knowledge, proposed against them which could reasonably be
         expected to have a Material Adverse Effect.

         (y) The Company and each of its subsidiaries carry, or are covered by,
         insurance in such amounts and covering such risks as is adequate for
         the conduct of their respective businesses and the value of their
         respective properties and as is customary for companies engaged in
         similar businesses in similar industries.

         (z) The Company and each of its subsidiaries maintain a system of
         internal accounting controls sufficient to provide reasonable
         assurances that (i) transactions are executed in accordance with
         management's general or specific authorization; (ii) transactions are
         recorded as necessary to permit preparation of financial statements in
         conformity with GAAP and to maintain accountability for assets; (iii)
         access to assets is permitted only in accordance with management's
         general or specific authorization; and (iv) the recorded accountability
         for assets is compared with existing assets at reasonable intervals and
         appropriate action is taken with respect to any differences.

         (aa) The minute books of the Company and each of its domestic
         subsidiaries have been made available to the Underwriter and counsel
         for the Underwriter, and such books (i) contain a complete summary of
         all meetings and actions of the board of directors (including each
         board committee) and shareholders (or analogous governing bodies and
         interest holders, as applicable) of the Company and each of its
         domestic subsidiaries since the time of its respective organization
         through the date of the latest meeting and action, and (ii) accurately
         in all material respects reflect all transactions referred to in such
         minutes.

         (bb) There is no franchise, lease, contract, agreement or document
         required by the Securities Act or by the Rules and Regulations to be
         described in the Prospectus or to be filed as an exhibit

                                                                               8

         to the Registration Statements which is not described or filed therein
         as required; and all descriptions of any such franchises, leases,
         contracts, agreements or documents contained in the Registration
         Statements are accurate and complete descriptions of such documents in
         all material respects, except for certain portions of such franchises,
         leases, contracts, agreements or documents omitted in reliance on Rule
         24b-2 under the Exchange Act. Other than as described in the
         Prospectus, no such franchise, lease, contract or agreement has been
         suspended or terminated for convenience or default by the Company or
         any of the other parties thereto, and neither the Company nor any of
         its subsidiaries has received notice or any other knowledge of any such
         pending or threatened suspension or termination, except for such
         pending or threatened suspensions or terminations that would not
         reasonably be expected to, singularly or in the aggregate, have a
         Material Adverse Effect. Further, other than as described in the
         Prospectus, all such franchises, leases, contracts, agreements and
         documents are in full force and effect and the Company and its
         subsidiaries, as applicable, are not in breach, violation or default of
         any such franchises, leases, contracts, agreements or documents and no
         event has occurred which with notice or lapse of time or both would
         constitute a breach, violation or default of any such franchises,
         leases, contracts, agreements or documents. The Company has not
         received any communication (whether written or oral) notifying the
         Company as to the termination or threatened termination or modification
         or threatened modification of any consulting, licensing, marketing,
         research and development, cooperative or any similar agreement.

         (cc) No relationship, direct or indirect, exists between or among the
         Company on the one hand, and the directors, officers, stockholders,
         customers or suppliers of the Company on the other hand, which is
         required to be described in the Prospectus and which is not so
         described.

         (dd) No person or entity has the right to require registration of
         shares of Common Stock or other securities of the Company because of
         the filing or effectiveness of the Registration Statements or
         otherwise, except for persons and entities who have expressly waived
         such right or who have been given timely and proper notice and have
         failed to exercise such right within the time or times required under
         the terms and conditions of such right.

         (ee) Neither the Company nor any of its subsidiaries own any "margin
         securities" as that term is defined in Regulation U of the Board of
         Governors of the Federal Reserve System (the "Federal Reserve Board"),
         and none of the proceeds of the sale of the Stock will be used,
         directly or indirectly, for the purpose of purchasing or carrying any
         margin security, for the purpose of reducing or retiring any
         indebtedness which was originally incurred to purchase or carry any
         margin security or for any other purpose which might cause any of the
         Securities to be considered a "purpose credit" within the meanings of
         Regulation T, U or X of the Federal Reserve Board.

         (ff) Neither the Company nor any of its subsidiaries is a party to any
         contract, agreement or understanding with any person that would give
         rise to a valid claim against the Company or the Underwriter for a
         brokerage commission, finder's fee or like payment in connection with
         the offering and sale of the Stock.

         (gg) No forward-looking statement (within the meaning of Section 27A of
         the Securities Act and Section 21E of the Exchange Act) contained in
         the Prospectus has been made or reaffirmed without a reasonable basis
         or has been disclosed other than in good faith.

         (hh) The Stock has been approved for listing subject to notice of
         issuance on the Nasdaq.

         (ii) The Company is in compliance with all applicable provisions of the
         Sarbanes-Oxley Act of 2002 and all rules and regulations promulgated
         thereunder or implementing the provisions thereof (the "Sarbanes-Oxley
         Act") that are then in effect and is actively taking steps to ensure

                                                                               9

         that it will be in compliance with other applicable provisions of the
         Sarbanes-Oxley Act not currently in effect upon and at all times after
         the effectiveness of such provisions.

         (jj) The Company has taken all necessary actions to ensure that, upon
         and at all times after Nasdaq shall have approved the Stock for
         inclusion, it will be in compliance with all applicable corporate
         governance requirements set forth in the Nasdaq Marketplace Rules that
         are then in effect and is actively taking steps to ensure that it will
         be in compliance with other applicable corporate governance
         requirements set forth in the Nasdaq Marketplace Rules not currently in
         effect upon and all times after the effectiveness of such requirements.

         (kk) Neither the Company nor any of its subsidiaries nor, to the best
         of the Company's knowledge, any employee or agent of the Company or any
         subsidiary, has made any contribution or other payment to any official
         of, or candidate for, any federal, state or foreign office in violation
         of any law or of the character required to be disclosed in the
         Prospectus.

         (ll) There are no transactions, arrangements or other relationships
         between and/or among the Company, any of its affiliates (as such term
         is defined in Rule 405 of the Securities Act) and any unconsolidated
         entity, including, but not limited to, any structure finance, special
         purpose or limited purpose entity that could reasonably be expected to
         materially affect the Company's liquidity or the availability of or
         requirements for its capital resources required to be described in the
         Prospectus which have not been described as required.

         (mm) There are no outstanding loans, advances (except normal advances
         for business expense in the ordinary course of business) or guarantees
         or indebtedness by the Company to or for the benefit of any of the
         officers or directors of the Company, except as disclosed in the
         Prospectus.

         (nn) There are no rulemaking or similar proceedings before the FDA or
         comparable federal, state, local or foreign government bodies which
         involve the Company or any of its subsidiaries, which, if the subject
         of an action unfavorable to the Company or any such subsidiary, could
         result in a Material Adverse Effect.

         (oo) The statements set forth in the Prospectus under the caption
         "Description of Capital Stock," insofar as they purport to constitute a
         summary of the terms of the capital stock of the Company, including the
         Common Stock, and under the captions "Risk Factors" and "Prospectus
         Supplement Summary," insofar as they purport to describe the provisions
         of the laws and documents referred to therein, are accurate, complete
         and fair.

3. PURCHASE, SALE AND DELIVERY OF OFFERED SECURITIES. On the basis of the
representations, warranties and agreements herein contained, but subject to the
terms and conditions herein set forth, the Company agrees to sell to the
Underwriter, and the Underwriter agrees to purchase from the Company, the Firm
Stock.

         The purchase price per share to be paid by the Underwriter to the
Company for the Stock will be $7.76 per share (the "Purchase Price").

The Company will deliver the Firm Stock to the Underwriter through the
facilities of The Depository Trust Company or, at the election of the
Underwriter, in the form of definitive certificates, in either case, issued in
such names and in such denominations as the Underwriter may direct by notice in
writing to the Company given at or prior to 12:00 Noon, New York time, on the
second full business day preceding the First Closing Date against payment of the
aggregate Purchase Price therefor in federal (same day) funds by wire transfer
to an account at J.P. Morgan Chase Bank - Houston, Texas, payable to the order
of the Company, all at the offices of Porter & Hedges, L.L.P., 700 Louisiana
Street, Suite 3500, Houston, Texas

                                                                              10

77002-2764. Time shall be of the essence, and delivery at the time and place
specified pursuant to this Agreement is a further condition of the obligations
of the Underwriter hereunder. The time and date of the delivery and closing
shall be at 10:00 A.M., New York time, on September 13, 2004, in accordance with
Rule 15c6-1 of the Exchange Act. The time and date of such payment and delivery
are herein referred to as the "First Closing Date". The First Closing Date and
the location of delivery of, and the form of payment for, the Firm Stock may be
varied by agreement between the Company and Wachovia.

         In the event the Underwriter elects to take delivery of the
certificates instead of delivery of the certificates through the facilities of
The Depository Trust Company, the Company shall make the certificates for the
Stock available to the Underwriter for examination in New York, New York at
least twenty-four hours prior to the First Closing Date.

         For the purpose of covering any over-allotments in connection with the
distribution and sale of the Firm Stock as contemplated by the Prospectus, the
Underwriter may purchase all or less than all of the Optional Stock. The price
per share to be paid for the Optional Stock shall be the Purchase Price. The
Company agrees to sell to the Underwriter the number of shares of Optional Stock
specified in the written notice by Wachovia described below and the Underwriter
agrees to purchase such shares of Optional Stock. The option granted hereby may
be exercised as to all or any part of the Optional Stock at any time, and from
time to time, not more than thirty (30) days subsequent to the date of this
Agreement. No Optional Stock shall be sold and delivered unless the Firm Stock
previously has been, or simultaneously is, sold and delivered. The right to
purchase the Optional Stock or any portion thereof may be surrendered and
terminated at any time upon notice by Wachovia to the Company.

         The option granted hereby may be exercised by written notice being
given to the Company by Wachovia setting forth the number of shares of the
Optional Stock to be purchased by the Underwriter and the date and time for
delivery of and payment for the Optional Stock. Each date and time for delivery
of and payment for the Optional Stock (which may be the First Closing Date, but
not earlier) is herein called the "Option Closing Date" and shall in no event be
earlier than two (2) business days nor later than five (5) business days after
written notice is given. (The Option Closing Date and the First Closing Date are
herein called the "Closing Dates".)

         The Company will deliver the Optional Stock to the Underwriter through
the facilities of The Depository Trust Company or, at the election of the
Underwriter, in the form of definitive certificates, in either case, issued in
such names and in such denominations as the Underwriter may direct by notice in
writing to the Company given at or prior to 12:00 Noon, New York time, on the
second full business day preceding the Option Closing Date against payment of
the aggregate Purchase Price therefor in federal (same day) funds by wire
transfer to an account at J.P. Morgan Chase Bank - Houston, Texas, payable to
the order of the Company, all at the offices of Porter & Hedges, L.L.P., 700
Louisiana Street, Suite 3500, Houston, Texas 77002-2764. Time shall be of the
essence, and delivery at the time and place specified pursuant to this Agreement
is a further condition of the obligations of the Underwriter hereunder. In the
event the Underwriter elects to take delivery of the certificates instead of
delivery of the certificates through the facilities of The Depository Trust
Company, the Company shall make the certificates for the Optional Stock
available to the Underwriter for examination in New York, New York not later
than 10:00 A.M., New York Time, on the business day preceding the Option Closing
Date. The Option Closing Date and the location of delivery of, and the form of
payment for, the Optional Stock may be varied by agreement between the Company
and Wachovia.

         The Underwriter proposes to offer the Stock for sale upon the terms and
conditions set forth in the Prospectus.

(4) FURTHER AGREEMENTS OF THE COMPANY. The Company agrees with the Underwriter
that:

                                                                              11

         (a) The Company will prepare the Rule 462(b) Registration Statement, if
         necessary, in a form approved by the Underwriter and file such Rule
         462(b) Registration Statement with the Commission on the date hereof;
         prepare the Prospectus in a form approved by the Underwriter and file
         such Prospectus pursuant to Rule 424(b) under the Securities Act not
         later than the second business day following the execution and delivery
         of this Agreement; make no further amendment or any supplement to the
         Registration Statements or to the Prospectus prior to the Option
         Closing Date to which the Underwriter shall reasonably object by notice
         to the Company after a reasonable period to review; advise the
         Underwriter, promptly after it receives notice thereof, of the time
         when any amendment to either Registration Statement has been filed or
         becomes effective or any supplement to the Prospectus or any amended
         Prospectus has been filed and to furnish the Underwriter with copies
         thereof; file promptly all reports and any definitive proxy or
         information statements required to be filed by the Company with the
         Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the
         Exchange Act subsequent to the date of the Prospectus and for so long
         as the delivery of a prospectus is required in connection with the
         offering or sale of the Stock; advise the Underwriter, promptly after
         it receives notice thereof, of the issuance by the Commission of any
         stop order or of any order preventing or suspending the use of any
         Preliminary Prospectus or the Prospectus, of the suspension of the
         qualification of the Stock for offering or sale in any jurisdiction, of
         the initiation or threatening of any proceeding for any such purpose,
         or of any request by the Commission for the amending or supplementing
         of the Registration Statements or the Prospectus or for additional
         information; and, in the event of the issuance of any stop order or of
         any order preventing or suspending the use of any Preliminary
         Prospectus or the Prospectus or suspending any such qualification, use
         promptly its best efforts to obtain its withdrawal.

         (b) If at any time prior to the expiration of nine months after the
         effective date of the Initial Registration Statement when a prospectus
         relating to the Stock is required to be delivered any event occurs as a
         result of which the Prospectus as then amended or supplemented would
         include any untrue statement of a material fact, or omit to state any
         material fact necessary to make the statements therein, in light of the
         circumstances under which they were made, not misleading, or if it is
         necessary at any time to amend the Prospectus or to file under the
         Exchange Act any document incorporated by reference in the Prospectus
         to comply with the Securities Act or the Exchange Act, the Company will
         promptly notify the Underwriter thereof and upon its request will
         prepare an amended or supplemented Prospectus or make an appropriate
         filing pursuant to Section 13 or 14 of the Exchange Act which will
         correct such statement or omission or effect such compliance. The
         Company will furnish without charge to the Underwriter and to any
         dealer in securities as many copies as the Underwriter may from time to
         time reasonably request of such amended or supplemented Prospectus; and
         in case the Underwriter is required to deliver a prospectus relating to
         the Stock nine months or more after the effective date of the Initial
         Registration Statement, the Company upon the request of the Underwriter
         and at the expense of the Underwriter will prepare promptly an amended
         or supplemented Prospectus as may be necessary to permit compliance
         with the requirements of Section 10(a)(3) of the Securities Act.

         (c) To furnish promptly to the Underwriter and to counsel for the
         Underwriter a signed copy of each of the Registration Statements as
         originally filed with the Commission, and each amendment thereto filed
         with the Commission, including all consents and exhibits filed
         therewith.

         (d) To deliver promptly to the Underwriter in New York City such number
         of the following documents as the Underwriter shall reasonably request:
         (i) conformed copies of the Registration Statements as originally filed
         with the Commission and each amendment thereto (in each case excluding
         exhibits), (ii) each Preliminary Prospectus, (iii) the Prospectus (not
         later than 10:00 A.M., New York time, of the business day following the
         execution and delivery of this Agreement) and any amended or
         supplemented Prospectus (not later than 10:00 A.M., New York


                                                                              12

         City, on the business day following the date of such amendment or
         supplement) and (iv) any document incorporated by reference in the
         Prospectus (excluding exhibits thereto).

         (e) To make generally available to its shareholders as soon as
         practicable, but in any event not later than eighteen months after the
         effective date of the Registration Statement (as defined in Rule 158(c)
         under the Securities Act), an earnings statement of the Company and its
         subsidiaries (which need not be audited) complying with Section 11(a)
         of the Securities Act and the Rules and Regulations (including, at the
         option of the Company, Rule 158).

         (f) The Company will promptly take from time to time such actions as
         the Underwriter may reasonably request to qualify the Stock for
         offering and sale under the securities or Blue Sky laws of such
         jurisdictions as the Underwriter may designate and to continue such
         qualifications in effect for so long as required for the distribution
         of the Stock; provided that the Company and its subsidiaries shall not
         be obligated to qualify as foreign corporations in any jurisdiction in
         which they are not so qualified or to file a general consent to service
         of process in any jurisdiction.

         (g) During the period of five years from the date hereof, the Company
         will deliver, upon request, to the Underwriter, (i) as soon as they are
         available, copies of all reports or other communications furnished to
         shareholders and (ii) as soon as they are available, copies of any
         reports and financial statements furnished or filed with the Commission
         pursuant to the Exchange Act or any national securities exchange or
         automatic quotation system on which the Stock is listed or quoted.

         (h) The Company will not directly or indirectly offer, sell, assign,
         transfer, pledge, contract to sell, or otherwise dispose of any shares
         of Common Stock or securities convertible into or exercisable or
         exchangeable for Common Stock for a period of 90 days (the "Restricted
         Period") from the date of the Prospectus without the prior written
         consent of Wachovia other than the Company's sale of the Stock
         hereunder, the issuance of restricted Common Stock or options to
         acquire shares of Common Stock pursuant to the Company's employee
         benefit plans, qualified stock option plans or other employee
         compensation plans existing on the date hereof and the issuance of
         shares of Common Stock pursuant to valid exercises of currently
         outstanding options, warrants or rights. Notwithstanding the foregoing,
         if (1) during the last eighteen (18) days of the Restricted Period the
         Company issues an earnings release or (2) prior to the expiration of
         the Restricted Period the Company announces that it will release
         earnings results during the 16-day period beginning on the last day of
         the Restricted Period, the restrictions imposed by this Section 4(h)
         shall continue to apply until the expiration of the 19-day period
         beginning on the issuance of the earnings release. The Company will
         cause each officer and director listed in Schedule A to furnish to the
         Underwriter, prior to the First Closing Date, a letter, substantially
         in the form of Exhibit I hereto, pursuant to which each such person
         shall agree not to directly or indirectly offer, sell, assign,
         transfer, pledge, contract to sell, or otherwise dispose of any shares
         of Common Stock or securities convertible into or exercisable or
         exchangeable for Common Stock for a period of 90 days from the date of
         the Prospectus, without the prior written consent of Wachovia and not
         to engage in any short selling of the Common Stock.

         (i) The Company will supply the Underwriter with copies of all
         correspondence to and from, and all documents issued to and by, the
         Commission in connection with the registration of the Stock under the
         Securities Act.

         (j) Prior to each of the Closing Dates the Company will furnish to the
         Underwriter, as soon as they have been prepared, copies of any
         unaudited interim consolidated financial statements of the Company for
         any periods subsequent to the periods covered by the financial
         statements appearing in the Registration Statement and the Prospectus.

                                                                              13

         (k) Prior to each of the Closing Dates, the Company will not issue any
         press release or other communication directly or indirectly or hold any
         press conference with respect to the Company, its condition, financial
         or otherwise, or earnings, business affairs or business prospects
         (except for routine oral marketing communications in the ordinary
         course of business and consistent with the past practices of the
         Company and of which the Underwriter is notified), without the prior
         written consent, such consent not to be unreasonably withheld or
         delayed, of the Underwriter, unless in the judgment of the Company and
         its counsel, and after notification to the Underwriter, such press
         release or communication is required by law.

         (l) Without limiting the provisions of section 4(h), in connection with
         the offering of the Stock, until Wachovia shall have notified the
         Company of the completion of the resale of the Stock, the Company will
         not, and will cause its affiliated purchasers (as defined in Regulation
         M under the Exchange Act) not to, either alone or with one or more
         other persons, bid for or purchase, for any account in which it or any
         of its affiliated purchasers has a beneficial interest, any Stock, or
         attempt to induce any person to purchase any Stock; and not to, and to
         cause its affiliated purchasers not to, make bids or purchase for the
         purpose of creating actual, or apparent, active trading in or of
         raising the price of the Stock.

         (m) The Company will not take any action prior to the Option Closing
         Date which would require the Prospectus to be amended or supplemented
         pursuant to Section 4(b).

         (n) The Company shall at all times comply with all applicable
         provisions of the Sarbanes-Oxley Act in effect from time to time.

         (o) The Company will apply the net proceeds from the sale of the Stock
         as set forth in the Prospectus under the heading "Use of Proceeds".

         (p) The Company shall at all times engage and maintain, at its
         expense, a registrar and transfer agent for the Stock.

5. PAYMENT OF EXPENSES. The Company agrees with the Underwriter to pay (a) the
costs incident to the authorization, issuance, sale, preparation and delivery of
the Stock and any taxes payable in that connection; (b) the costs incident to
the registration of the Stock under the Securities Act; (c) the costs incident
to the preparation, printing and distribution of the Registration Statement,
Preliminary Prospectus, Prospectus any amendments and exhibits thereto or any
document incorporated by reference therein; (d) the costs of printing,
reproducing and distributing this Agreement by mail, telex or other means of
communications; (e) any applicable listing or other fees; (f) the fees and
expenses (including related fees and expenses of counsel to the Underwriter) of
qualifying the Stock under the securities laws of the several jurisdictions as
provided in Section 4(f) and of preparing, printing and distributing Blue Sky
Memoranda and Legal Investment Surveys (including related fees and expenses of
counsel to the Underwriter); (g) all fees and expenses of the registrar and
transfer agent of the Stock; and (h) all other costs and expenses incident to
the performance of the obligations of the Company under this Agreement
(including, without limitation, the fees and expenses of the Company's counsel
and the Company's independent accountants); provided that, except as otherwise
provided in this Section 5 and in Section 9, the Underwriter shall pay its own
costs and expenses, including the fees and expenses of its counsel, any transfer
taxes on the Stock which it may sell and the expenses of advertising any
offering of the Stock made by the Underwriter.

6. CONDITIONS OF UNDERWRITER'S OBLIGATIONS. The obligations of the Underwriter
are subject to the accuracy, when made and on each of the Closing Dates, of the
representations and warranties of the Company contained herein, to the accuracy
of the statements of the Company made in any certificates

                                                                              14

pursuant to the provisions hereof, to the performance by the Company of its
obligations hereunder, and to each of the following additional terms and
conditions:

         (a) No stop order suspending the effectiveness of either the
         Registration Statements shall have been issued and no proceedings for
         that purpose shall have been initiated or threatened by the Commission,
         and any request for additional information on the part of the
         Commission (to be included in the Registration Statements or the
         Prospectus or otherwise) shall have been complied with to the
         reasonable satisfaction of the Underwriter. The Rule 462(b)
         Registration Statement, if any, and the Prospectus shall have been
         timely filed with the Commission in accordance with Section 4(a).

         (b) The Underwriter shall not have discovered and disclosed to the
         Company on or prior to the Closing Date that the Registration Statement
         or the Prospectus or any amendment or supplement thereto contains an
         untrue statement of a fact which, in the opinion of counsel for the
         Underwriter, is material or omits to state any fact which, in the
         opinion of such counsel, is material and is required to be stated
         therein or is necessary to make the statements therein not misleading.

         (c) All corporate proceedings and other legal matters incident to the
         authorization, form and validity of each of this Agreement, the Stock,
         the Registration Statement and the Prospectus and all other legal
         matters relating to this Agreement and the transactions contemplated
         hereby shall be reasonably satisfactory in all material respects to
         counsel for the Underwriter, and the Company shall have furnished to
         such counsel all documents and information that they may reasonably
         request to enable them to pass upon such matters.

         (d) Porter & Hedges, L.L.P. or Wood, Phillips, Katz, Clark & Mortimer
         shall have furnished to the Underwriter such counsel's or counsels'
         written opinion or opinions, as counsel to the Company, addressed to
         the Underwriter and dated the Closing Date, in form and substance
         reasonably satisfactory to the Underwriter, to the effect that:

             (i)      The Company and each of its domestic subsidiaries have
                      been duly incorporated and are validly existing as
                      corporations or other legal entities in good standing
                      under the laws of their respective jurisdictions of
                      organization, are duly qualified to do business and are in
                      good standing as foreign corporations in each jurisdiction
                      identified to us by the Company as those in which their
                      respective ownership or lease of property or the conduct
                      of their respective businesses requires such
                      qualification, and have all power and authority necessary
                      to own or hold their respective properties and to conduct
                      the businesses in which they are engaged, except where the
                      failure to so qualify or have such power or authority
                      would not have, singularly or in the aggregate, a Material
                      Adverse Effect.

             (ii)     The Company has an authorized capitalization as set forth
                      in the Prospectus, and all of the issued shares of capital
                      stock of the Company, including the Stock being delivered
                      on the Closing Date, have been duly and validly authorized
                      and issued, are fully paid and nonassessable and conform
                      to the description thereof contained in the Prospectus.

             (iii)    All the outstanding shares of capital stock (or analogous
                      ownership interests, as applicable) of each domestic
                      subsidiary of the Company have been duly authorized and
                      validly issued, are fully paid and nonassessable and,
                      except to the extent set forth in the Prospectus, are
                      owned by the Company directly or indirectly through one or
                      more wholly-owned domestic subsidiaries, free and

                                                                              15

                      clear of any claim, lien, encumbrance, security interest,
                      restriction upon voting or transfer or any other claim of
                      any third party.

             (iv)     There are no preemptive or other rights to subscribe for
                      or to purchase, nor any restriction upon the voting or
                      transfer of, any shares of the Stock pursuant to the
                      Company's charter or by-laws or any agreement or other
                      instrument known to such counsel.

             (v)      This Agreement has been duly authorized, executed and
                      delivered by the Company.

             (vi)     The execution, delivery and performance of this Agreement
                      and the consummation of the transactions contemplated
                      hereby will not conflict with or result in a breach or
                      violation of any of the terms or provisions of, or
                      constitute (with or without notice or lapse of time or
                      both) a default under any indenture, mortgage, deed of
                      trust, loan agreement or other agreement or instrument
                      known to such counsel after reasonable investigation to
                      which the Company or any of its domestic subsidiaries is a
                      party or by which the Company or any of its domestic
                      subsidiaries is bound or to which any of the properties or
                      assets of the Company or any of its domestic subsidiaries
                      is subject, nor will such actions result in any violation
                      of the Charter or by-laws (or analogous governing
                      instruments, as applicable) of the Company or of any of
                      its domestic subsidiaries or any statute or any order,
                      rule or regulation of any court or governmental agency or
                      body or court having jurisdiction over the Company or any
                      of its domestic subsidiaries or any of their properties or
                      assets.

             (vii)    Except for the registration of the Stock under the
                      Securities Act and such consents, approvals,
                      authorizations, registrations or qualifications as may be
                      required under the Exchange Act and applicable state
                      securities laws in connection with the purchase and
                      distribution of the Stock by the Underwriter, no consent,
                      approval, authorization or order of, or filing or
                      registration with, any court or governmental agency or
                      body is required for the execution, delivery and
                      performance of this Agreement by the Company and the
                      consummation of the transactions contemplated hereby.

             (viii)   The statements in the Prospectus under the heading
                      "Description of Capital Stock," "Risk Factors - Risks
                      Relating to Intellectual Property" and "Risk Factors -
                      Risks Related To Our Common Stock Outstanding," to the
                      extent that they constitute summaries of matters of law or
                      regulation or legal conclusions, have been reviewed by
                      such counsel and fairly summarize the matters described
                      therein in all material respects. The statements set forth
                      in the Company's Annual Report on Form 10-K for the year
                      ended December 31, 2003, as amended, set forth under "Part
                      I - Item 1 - Business - Licenses and Patents," to the
                      extent that they constitute summaries of matters of law or
                      regulation or legal conclusions, have been reviewed by
                      such counsel and fairly summarize the matters described
                      therein in all material respects.

             (ix)     Except for descriptions with respect to statutes, legal or
                      governmental proceedings relating to the FDA, the
                      description in the Registration Statements and Prospectus
                      of statutes, legal or governmental proceedings and
                      contracts and other documents are accurate in all material
                      respects; and, except with respect to statutes, legal or
                      governmental proceedings relating to the FDA, to the best
                      of

                                                                              16

                      such counsel's knowledge, there are no statutes, legal or
                      governmental proceedings, contracts or other documents of
                      a character required to be described in the Registration
                      Statement or Prospectus or to be filed as exhibits to the
                      Registration Statement which are not described or filed as
                      required.

             (x)      Neither the Company nor any of its domestic subsidiaries
                      (i) is in violation of its charter or by-laws (or
                      analogous governing instruments, as applicable), (ii) is
                      in default, and no event has occurred, which, with notice
                      or lapse of time or both, would constitute a default, in
                      the due performance or observance of any term, covenant or
                      condition contained in any agreement or instrument to
                      which it is a party or by which it is bound or to which
                      any of its properties or assets is subject of which we
                      have knowledge or (iii) is in violation of any law,
                      ordinance, governmental rule, regulation or court decree
                      to which it or its property or assets may be subject of
                      which we have knowledge or has failed to obtain any
                      license, permit, certificate, franchise or other
                      governmental authorization or permit necessary to the
                      ownership of its property or to the conduct of its
                      business except, in the case of clauses (ii) and (iii),
                      for those defaults, violations or failures which,
                      singularly or in the aggregate, would not have a Material
                      Adverse Effect.

             (xi)     To the best of such counsel's knowledge and other than as
                      set forth in the Prospectus, there are no legal or
                      governmental proceedings pending, except for the
                      modification of intellectual property rights pursuant to
                      proceedings involving the processing and examination of
                      patent and trademark applications and patents before
                      governmental agencies or bodies, to which the Company or
                      any of its domestic subsidiaries is a party or of which
                      any property or asset of the Company or any of its
                      domestic subsidiaries is the subject which, singularly or
                      in the aggregate, if determined adversely to the Company
                      or any of its domestic subsidiaries, might have a Material
                      Adverse Effect or would prevent or adversely affect the
                      ability of the Company to perform its obligations under
                      this Agreement; and, to the best of such counsel's
                      knowledge, no such proceedings are threatened or
                      contemplated by governmental authorities or threatened by
                      others.

             (xii)    To the best of such counsel's knowledge, the Company and
                      its domestic subsidiaries own or possess valid and
                      enforceable licenses or other rights to use all patents,
                      patent applications, trademarks, trademark registrations,
                      service marks, service mark registrations, trade names,
                      domain names, domain name registrations, copyrights,
                      licenses, inventions, trade secrets and rights used by the
                      Company or its domestic subsidiaries in connection with
                      their respective businesses (collectively, the
                      "Intellectual Property"). To the best of such counsel's
                      knowledge and other than as described in the Prospectus
                      (A) there are no third parties who have any rights in the
                      Intellectual Property that could preclude the Company or
                      any of its domestic subsidiaries, as applicable, from
                      conducting its business as currently conducted or as
                      presently contemplated to be conducted as described in the
                      Prospectus, (B) there are no pending or threatened
                      actions, suits, proceedings, investigations or claims by
                      others challenging the rights of the Company or any of its
                      domestic subsidiaries, as applicable, or, if the
                      Intellectual Property is licensed to the Company or any of
                      its domestic subsidiaries, as applicable, in respect of
                      any third party licensor, and (C) neither the Company nor
                      any of its domestic subsidiaries has and, to the extent
                      any Intellectual Property is licensed to the Company or
                      any of its domestic subsidiaries, as applicable, no third
                      party licensor has, infringed, or received any

                                                                              17

                      notice of infringement of or conflict with, any rights of
                      others with respect to the Intellectual Property.

             (xiii)   The Registration Statement was declared effective under
                      the Securities Act as of the date and time specified in
                      such opinion, the Rule 462(b) Registration Statement, if
                      any, was filed with the Commission on the date specified
                      therein, the Prospectus was filed with the Commission
                      pursuant to the subparagraph of Rule 424(b) of the Rules
                      and Regulations specified in such opinion on the date
                      specified therein and no stop order suspending the
                      effectiveness of the Registration Statement has been
                      issued and, to the knowledge of such counsel, no
                      proceeding for that purpose is pending or threatened by
                      the Commission.

             (xiv)    The Registration Statements, as of the respective
                      effective dates and the Prospectus, as of its date, and
                      any further amendments or supplements thereto, as of their
                      respective dates, made by the Company prior to the Closing
                      Date (other than the financial statements and other
                      financial data contained therein, as to which such counsel
                      need express no opinion) complied as to form in all
                      material respects with the requirements of the Securities
                      Act and the Rules and Regulations and the documents
                      incorporated by reference in the Prospectus and any
                      further amendment or supplement to any such incorporated
                      document made by the Company prior to the Closing Date
                      (other than the financial statements and related schedules
                      therein, as to which such counsel need express no
                      opinion), when they became effective or were filed with
                      the Commission, as the case may be, complied as to form in
                      all material respects with the requirements of the
                      Securities Act or the Exchange Act, as applicable, and the
                      Rules and Regulations and the rules and regulations of the
                      Commission under the Exchange Act, as applicable.

             (xv)     To the best of such counsel's knowledge no person or
                      entity has the right to require registration of shares of
                      Common Stock or other securities of the Company because of
                      the filing or effectiveness of the Registration Statements
                      or otherwise, except for persons and entities who have
                      expressly waived such right or who have been given proper
                      notice and have failed to exercise such right within the
                      time or times required under the terms and conditions of
                      such right.

             (xvi)    Neither the Company nor any of its domestic subsidiaries
                      is an "investment company" within the meaning of the
                      Investment Company Act and the rules and regulations of
                      the Commission thereunder.

             (xvii)   The Company meets the requirements for the use of Form S-3
                      under the Securities Act and the Rules and Regulations.
                      The Registration Statements meet the requirements set
                      forth in Rule 415(a)(1)(x) of the Rules and Regulations.

             (xviii)  The Company and its domestic subsidiaries possess all
                      licenses, certificates, authorizations and permits issued
                      by the appropriate federal, state or foreign regulatory
                      authorities necessary to conduct their businesses, except
                      for such licenses, certificates, authorizations or permits
                      the failure of which to maintain would not have a Material
                      Adverse Effect. Neither the Company nor any of its
                      domestic subsidiaries has received any notice of
                      proceedings relating to the revocation or modification of
                      any such certificate, authorization or permit which,
                      singly or in the aggregate, if the subject of an
                      unfavorable decision, ruling or finding, would have a
                      Material Adverse Effect. To the best of such counsel's

                                                                              18

                      knowledge, the Company and its domestic subsidiaries are
                      in compliance with all applicable federal, state, local
                      and foreign laws, regulations, orders and decrees
                      governing their business, except where noncompliance would
                      not, singly or in the aggregate, have a Material Adverse
                      Effect.

                  Such counsel shall also have furnished to the Underwriter a
         written statement, addressed to the Underwriter and dated the Closing
         Date, in form and substance satisfactory to the Underwriter, to the
         effect that (x) such counsel has acted as counsel to the Company in
         connection with the preparation of the Registration Statements (y)
         based on such counsel's examination of the Registration Statements and
         such counsel's investigations made in connection with the preparation
         of the Registration Statements and "conferences with certain officers
         and employees of and with auditors for and counsel to the Company",
         such counsel has no reason to believe that (I) the Registration
         Statements, as of the respective effective dates, contained any untrue
         statement of a material fact or omitted to state any material fact
         required to be stated therein or necessary in order to make the
         statements therein not misleading, or that the Prospectus contains any
         untrue statement of a material fact or omits to state any material fact
         required to be stated therein or necessary in order to make the
         statements therein, in light of the circumstances under which they were
         made, not misleading or (II) any document incorporated by reference in
         the Prospectus or any further amendment or supplement to any such
         incorporated document, when they became effective or were filed with
         the Commission, as the case may be, contained, in the case of a
         registration statement which became effective under the Securities Act,
         any untrue statement of a material fact or omitted to state any
         material fact required to be stated therein or necessary in order to
         make the statements therein not misleading, or, in the case of other
         documents which were filed under the Exchange Act with the Commission,
         any untrue statement of a material fact or omitted to state any
         material fact necessary in order to make the statements therein, in
         light of the circumstances under which they were made, not misleading;
         it being understood that such counsel need express no opinion as to the
         financial statements or other financial data contained in the
         Registration Statement or the Prospectus.

                  The foregoing opinion and statement may be qualified by a
         statement to the effect that such counsel has not independently
         verified the accuracy, completeness or fairness of the statements
         contained in the Registration Statement or the Prospectus and takes no
         responsibility therefor except to the extent set forth in the opinion
         described in clauses (viii) and (ix) above.

         (e) The Underwriter shall have received from Skadden, Arps, Slate,
         Meagher & Flom LLP, counsel for the Underwriter, such opinion or
         opinions, dated the Closing Date, with respect to such matters as the
         Underwriter may reasonably require, and the Company shall have
         furnished to such counsel such documents as they request for enabling
         them to pass upon such matters.

         (f) On the date hereof, the Underwriter shall have received from KPMG
         LLP a letter, addressed to the Underwriter and dated such date, in form
         and substance satisfactory to the Underwriter (i) confirming that they
         are independent certified public accountants with respect to the
         Company and its subsidiaries within the meaning of the Securities Act
         and the Rules and Regulations and (ii) stating the conclusions and
         findings of such firm with respect to the financial statements and
         certain financial information contained or incorporated by reference in
         the Prospectus.

         (g) On the Closing Date, the Underwriter shall have received a letter
         (the "bring-down letter") from KPMG LLP addressed to the Underwriter
         and dated the Closing Date confirming, as of the date of the bring-down
         letter (or, with respect to matters involving changes or developments
         since the respective dates as of which specified financial information
         is given in the Prospectus as of a date not more than three business
         days prior to the date of the bring-down

                                                                              19

         letter), the conclusions and findings of such firm with respect to the
         financial information and other matters covered by its letter delivered
         to the Underwriter on the same date as the date of execution of this
         Agreement pursuant to Section 6(f).

         (h) The Company shall have furnished to the Underwriter a certificate,
         dated the Closing Date, of its Chairman of the Board, its President or
         a Vice President and its chief financial officer stating that (i) such
         officers have carefully examined the Registration Statements and the
         Prospectus and, in their opinion, the Registration Statements as of
         their respective effective dates and the Prospectus, as of each such
         effective date, did not include any untrue statement of a material fact
         and did not omit to state a material fact required to be stated therein
         or necessary to make the statements therein not misleading, (ii) since
         the effective date of the Initial Registration Statement no event has
         occurred which should have been set forth in a supplement or amendment
         to the Registration Statements or the Prospectus, (iii) to the best of
         their knowledge after reasonable investigation, as of the Closing Date,
         the representations and warranties of the Company in this Agreement are
         true and correct and the Company has complied with all agreements and
         satisfied all conditions on its part to be performed or satisfied
         hereunder at or prior to the Closing Date, and (iv) subsequent to the
         date of the most recent financial statements included or incorporated
         by reference in the Prospectus, there has been no material adverse
         change in the financial position or results of operation of the Company
         and its subsidiaries, or any change, or any development including a
         prospective change, in or affecting the condition (financial or
         otherwise), results of operations, business or prospects of the Company
         and its subsidiaries taken as a whole, except as set forth in the
         Prospectus.

         (i) (i) Neither the Company nor any of its subsidiaries shall have
         sustained since the date of the latest audited financial statements
         included or incorporated by reference in the Prospectus any loss or
         interference with its business from fire, explosion, flood or other
         calamity, whether or not covered by insurance, or from any labor
         dispute or court or governmental action, order or decree, otherwise
         than as set forth or contemplated in the Prospectus and (ii) since such
         date there shall not have been any change in the capital stock or
         long-term debt of the Company or any of its subsidiaries or any change,
         or any development involving a prospective change, in or affecting the
         business, general affairs, management, financial position,
         stockholders' equity or results of operations of the Company and its
         subsidiaries, otherwise than as set forth or contemplated in the
         Prospectus, the effect of which, in any such case described in clause
         (i) or (ii), is, in the judgment of the Underwriter, so material and
         adverse as to make it impracticable or inadvisable to proceed with the
         sale or delivery of the Stock on the terms and in the manner
         contemplated in the Prospectus.

         (j) No action shall have been taken and no statute, rule, regulation or
         order shall have been enacted, adopted or issued by any governmental
         agency or body which would, as of the Closing Date, prevent the
         issuance or sale of the Stock or materially and adversely affect or
         potentially materially and adversely affect the business or operations
         of the Company; and no injunction, restraining order or order of any
         other nature by any federal or state court of competent jurisdiction
         shall have been issued as of the Closing Date which would prevent the
         issuance or sale of the Stock or materially and adversely affect or
         potentially materially and adversely affect the business or operations
         of the Company.

         (k) Subsequent to the execution and delivery of this Agreement there
         shall not have occurred any of the following: (i) trading in securities
         generally on the New York Stock Exchange or the American Stock Exchange
         or in the over-the-counter market, or trading in any securities of the
         Company on any exchange or in the over-the-counter market, shall have
         been suspended or minimum or maximum prices or maximum range for prices
         shall have been established on any such exchange or such market by the
         Commission, by such exchange or by any other regulatory

                                                                              20

         body or governmental authority having jurisdiction, (ii) a banking
         moratorium shall have been declared by Federal or state authorities or
         a material disruption has occurred in commercial banking or securities
         settlement or clearance services in the United States, (iii) the United
         States shall have become engaged in further hostilities, or the subject
         of any further act or acts of terrorism, or there shall have been an
         escalation in hostilities involving the United States, or there shall
         have been a declaration of a national emergency or war by the United
         States or (iv) there shall have occurred such a material adverse change
         in general economic, political or financial conditions (or the effect
         of international conditions on the financial markets in the United
         States shall be such) as to make it, in the judgment of the
         Underwriter, impracticable or inadvisable to proceed with the sale or
         delivery of the Stock on the terms and in the manner contemplated in
         the Prospectus.

         (l) Nasdaq shall have approved the Stock for listing, subject only to
         official notice of issuance.

         (m) Wachovia shall have received the written agreements, substantially
         in the form of Exhibit I hereto, of the officers and directors of the
         Company listed in Schedule A to this Agreement.

         All opinions, letters, evidence and certificates mentioned above or
elsewhere in this Agreement shall be deemed to be in compliance with the
provisions hereof only if they are in form and substance reasonably satisfactory
to counsel for the Underwriter.

7. INDEMNIFICATION AND CONTRIBUTION.

         (a) The Company shall indemnify and hold harmless the Underwriter, its
         officers, employees, representatives and agents and each person, if
         any, who controls the Underwriter within the meaning of the Securities
         Act (collectively the "Underwriter Indemnified Parties" and, each an
         "Underwriter Indemnified Party") against any loss, claim, damage or
         liability, joint or several, or any action in respect thereof, to which
         that Underwriter Indemnified Party may become subject, under the
         Securities Act or otherwise, insofar as such loss, claim, damage,
         liability or action arises out of or is based upon (i) any untrue
         statement or alleged untrue statement of a material fact contained in
         the Preliminary Prospectus, either of the Registration Statements or
         the Prospectus or in any amendment or supplement thereto or (ii) the
         omission or alleged omission to state in any Preliminary Prospectus,
         either of the Registration Statements or the Prospectus or in any
         amendment or supplement thereto a material fact required to be stated
         therein or necessary to make the statements therein not misleading and
         shall reimburse each Underwriter Indemnified Party promptly upon demand
         for any legal or other expenses reasonably incurred by that Underwriter
         Indemnified Party in connection with investigating or preparing to
         defend or defending against or appearing as a third party witness in
         connection with any such loss, claim, damage, liability or action as
         such expenses are incurred; provided, however, that the Company shall
         not be liable in any such case to the extent that any such loss, claim,
         damage, liability or action arises out of or is based upon an untrue
         statement or alleged untrue statement in or omission or alleged
         omission from the Preliminary Prospectus, either of the Registration
         Statements or the Prospectus or any such amendment or supplement in
         reliance upon and in conformity with written information furnished to
         the Company by or on behalf of the Underwriter specifically for use
         therein, which information the parties hereto agree is limited to the
         Underwriter's Information (as defined in Section 16). This indemnity
         agreement is not exclusive and will be in addition to any liability
         which the Company might otherwise have and shall not limit any rights
         or remedies which may otherwise be available at law or in equity to
         each Underwriter Indemnified Party.


                                                                              21

         (b) The Underwriter shall indemnify and hold harmless the Company its
         officers, employees, representatives and agents, each of its directors
         and each person, if any, who controls the Company within the meaning of
         the Securities Act (collectively the "Company Indemnified Parties" and
         each a "Company Indemnified Party") against any loss, claim, damage or
         liability, joint or several, or any action in respect thereof, to which
         the Company Indemnified Parties may become subject, under the
         Securities Act or otherwise, insofar as such loss, claim, damage,
         liability or action arises out of or is based upon (i) any untrue
         statement or alleged untrue statement of a material fact contained in
         the Preliminary Prospectus, either of the Registration Statements or
         the Prospectus or in any amendment or supplement thereto or (ii) the
         omission or alleged omission to state therein a material fact required
         to be stated therein or necessary to make the statements therein not
         misleading, but in each case only to the extent that the untrue
         statement or alleged untrue statement or omission or alleged omission
         was made in reliance upon and in conformity with written information
         furnished to the Company by or on behalf of the Underwriter
         specifically for use therein, and shall reimburse the Company
         Indemnified Parties for any legal or other expenses reasonably incurred
         by such parties in connection with investigating or preparing to defend
         or defending against or appearing as third party witness in connection
         with any such loss, claim, damage, liability or action as such expenses
         are incurred; provided that the parties hereto hereby agree that such
         written information provided by the Underwriter consists solely of the
         Underwriter's Information. This indemnity agreement is not exclusive
         and will be in addition to any liability which the Underwriter might
         otherwise have and shall not limit any rights or remedies which may
         otherwise be available at law or in equity to the Company Indemnified
         Parties.

         (c) Promptly after receipt by an indemnified party under this Section 7
         of notice of any claim or the commencement of any action, the
         indemnified party shall, if a claim in respect thereof is to be made
         against the indemnifying party under this Section 7, notify the
         indemnifying party in writing of the claim or the commencement of that
         action; provided, however, that the failure to notify the indemnifying
         party shall not relieve it from any liability which it may have under
         this Section 7 except to the extent it has been materially prejudiced
         by such failure; and, provided, further, that the failure to notify the
         indemnifying party shall not relieve it from any liability which it may
         have to an indemnified party otherwise than under this Section 7. If
         any such claim or action shall be brought against an indemnified party,
         and it shall notify the indemnifying party thereof, the indemnifying
         party shall be entitled to participate therein and, to the extent that
         it wishes, jointly with any other similarly notified indemnifying
         party, to assume the defense thereof with counsel reasonably
         satisfactory to the indemnified party. After notice from the
         indemnifying party to the indemnified party of its election to assume
         the defense of such claim or action, the indemnifying party shall not
         be liable to the indemnified party under this Section 7 for any legal
         or other expenses subsequently incurred by the indemnified party in
         connection with the defense thereof other than reasonable costs of
         investigation; provided, however, that any indemnified party shall have
         the right to employ separate counsel in any such action and to
         participate in the defense thereof but the fees and expenses of such
         counsel shall be at the expense of such indemnified party unless (i)
         the employment thereof has been specifically authorized by the
         indemnifying party in writing, (ii) such indemnified party shall have
         been advised by such counsel that there may be one or more legal
         defenses available to it which are different from or additional to
         those available to the indemnifying party and in the reasonable
         judgment of such counsel it is advisable for such indemnified party to
         employ separate counsel or (iii) the indemnifying party has failed to
         assume the defense of such action and employ counsel reasonably
         satisfactory to the indemnified party, in which case, if such
         indemnified party notifies the indemnifying party in writing that it
         elects to employ separate counsel at the expense of the indemnifying
         party, the indemnifying party shall not have the right to assume the
         defense of such action on behalf of such indemnified party, it being
         understood, however, that the indemnifying party shall not, in
         connection with any one such action or separate but substantially
         similar or


                                                                              22

         related actions in the same jurisdiction arising out of the same
         general allegations or circumstances, be liable for the reasonable fees
         and expenses of more than one separate firm of attorneys at any time
         for all such indemnified parties, which firm shall be designated in
         writing by Wachovia, if the indemnified parties under this Section 7
         consist of any Underwriter Indemnified Party, or by the Company if the
         indemnified parties under this Section 7 consist of any Company
         Indemnified Parties. Each indemnified party, as a condition of the
         indemnity agreements contained in Sections 7(a) and 7(b), shall use all
         reasonable efforts to cooperate with the indemnifying party in the
         defense of any such action or claim. Subject to the provisions of
         Section 7(d) below, no indemnifying party shall be liable for any
         settlement of any such action effected without its written consent
         (which consent shall not be unreasonably withheld), but if settled with
         its written consent or if there be a final judgment for the plaintiff
         in any such action, the indemnifying party agrees to indemnify and hold
         harmless any indemnified party from and against any loss or liability
         by reason of such settlement or judgment.

         (d) If at any time an indemnified party shall have requested that an
         indemnifying party reimburse the indemnified party for fees and
         expenses of counsel, such indemnifying party agrees that it shall be
         liable for any settlement of the nature contemplated by this Section 7
         effected without its written consent if (i) such settlement is entered
         into more than 45 days after receipt by such indemnifying party of the
         request for reimbursement, (ii) such indemnifying party shall have
         received notice of the terms of such settlement at least 30 days prior
         to such settlement being entered into and (iii) such indemnifying party
         shall not have reimbursed such indemnified party in accordance with
         such request prior to the date of such settlement.

         (e) If the indemnification provided for in this Section 7 is
         unavailable or insufficient to hold harmless an indemnified party under
         Section 7(a) or 7(b), then each indemnifying party shall, in lieu of
         indemnifying such indemnified party, contribute to the amount paid or
         payable by such indemnified party as a result of such loss, claim,
         damage or liability, or action in respect thereof, (i) in such
         proportion as shall be appropriate to reflect the relative benefits
         received by the Company on the one hand and the Underwriter on the
         other from the offering of the Stock or if the allocation provided by
         clause (i) above is not permitted by applicable law, in such proportion
         as is appropriate to reflect not only the relative benefits referred to
         in clause (i) above but also the relative fault of the Company on the
         one hand and the Underwriter on the other with respect to the
         statements or omissions which resulted in such loss, claim, damage or
         liability, or action in respect thereof, as well as any other relevant
         equitable considerations. The relative benefits received by the Company
         on the one hand and the Underwriter on the other with respect to such
         offering shall be deemed to be in the same proportion as the total net
         proceeds from the offering of the Stock purchased under this Agreement
         (before deducting expenses) received by the Company bear to the total
         underwriting discounts and commissions received by the Underwriter with
         respect to the Stock purchased under this Agreement, in each case as
         set forth in the table on the cover page of the Prospectus. The
         relative fault shall be determined by reference to, among other things,
         whether the untrue or alleged untrue statement of a material fact or
         the omission or alleged omission to state a material fact relates to
         information supplied by the Company on the one hand or the Underwriter
         on the other, the intent of the parties and their relative knowledge,
         access to information and opportunity to correct or prevent such untrue
         statement or omission; provided that the parties hereto agree that the
         written information furnished to the Company by or on behalf of the
         Underwriter for use in any Preliminary Prospectus, either of the
         Registration Statements or the Prospectus consists solely of the
         Underwriter's Information. The Company and the Underwriter agree that
         it would not be just and equitable if contributions pursuant to this
         Section 7(e) were to be determined by pro rata allocation or by any
         other method of allocation which does not take into account the
         equitable considerations referred to herein. The amount paid or payable
         by an indemnified party as a result of the loss, claim, damage or
         liability, or action in respect thereof, referred to above in this
         Section 7(e) shall be deemed to include, for purposes of

                                                                              23

         this Section 7(e), any legal or other expenses reasonably incurred by
         such indemnified party in connection with investigating or defending
         any such action or claim. Notwithstanding the provisions of this
         Section 7(e), the Underwriter shall not be required to contribute any
         amount in excess of the amount by which the total price at which the
         Stock underwritten by it and distributed to the public was offered to
         the public less the amount of any damages which the Underwriter has
         otherwise paid or become liable to pay by reason of any untrue or
         alleged untrue statement or omission or alleged omission. No person
         guilty of fraudulent misrepresentation (within the meaning of Section
         11(f) of the Securities Act) shall be entitled to contribution from any
         person who was not guilty of such fraudulent misrepresentation.

8. TERMINATION. The obligations of the Underwriter hereunder may be terminated
by Wachovia, in its absolute discretion by notice given to and received by the
Company prior to delivery of and payment for the Firm Stock if, prior to that
time, any of the events described in Sections 6(i) or 6(k) have occurred or if
the Underwriter shall decline to purchase the Stock for any reason permitted
under this Agreement.

9. REIMBURSEMENT OF UNDERWRITER'S EXPENSES. If (a) this Agreement shall have
been terminated pursuant to Section 8, (b) the Company shall fail to tender the
Stock for delivery to the Underwriter for any reason not permitted under this
Agreement, or (c) the Underwriter shall decline to purchase the Stock for any
reason permitted under this Agreement the Company shall reimburse the
Underwriter for the fees and expenses of its counsel and for such other
out-of-pocket expenses as shall have been reasonably incurred by it in
connection with this Agreement and the proposed purchase of the Stock, and upon
demand the Company shall pay the full amount thereof to Wachovia. If this
Agreement is terminated pursuant to Section 10 by reason of the default of the
Underwriter, the Company shall not be obligated to reimburse the defaulting
Underwriter on account of those expenses.

10. UNDERWRITER DEFAULT. If the Underwriter shall default in its obligations to
purchase shares of Stock hereunder, this Agreement shall terminate. Any
termination of this Agreement pursuant to this Section 10 shall be without
liability on the part of the Company, except expenses to be paid or reimbursed
pursuant to Sections 5 and 9 and except the provisions of Section 7 shall not
terminate and shall remain in effect.

11. SUCCESSORS; PERSONS ENTITLED TO BENEFIT OF AGREEMENT. This Agreement shall
inure to the benefit of and be binding upon the Underwriter, the Company and
their respective successors. Nothing expressed or mentioned in this Agreement is
intended or shall be construed to give any person other than the persons
mentioned in the preceding sentence any legal or equitable right, remedy or
claim under or in respect of this Agreement, or any provisions herein contained,
this Agreement and all conditions and provisions hereof being intended to be and
being for the sole and exclusive benefit of such persons and for the benefit of
no other person; except that the representations, warranties, covenants,
agreements and indemnities of the Company contained in this Agreement shall also
be for the benefit of the Underwriter Indemnified Parties, and the indemnities
of the Underwriter shall also be for the benefit of the Company Indemnified
Parties. It is understood that the Underwriter's responsibility to the Company
is solely contractual in nature and the Underwriter does not owe the Company, or
any other party, any fiduciary duty as a result of this Agreement.

12. SURVIVAL OF INDEMNITIES, REPRESENTATIONS, WARRANTIES, ETC. The respective
indemnities, covenants, agreements, representations, warranties and other
statements of the Company and the Underwriter, as set forth in this Agreement or
made by them respectively, pursuant to this Agreement, shall remain in full
force and effect, regardless of any investigation made by or on behalf of the
Underwriter, the Company or any person controlling any of them and shall survive
delivery of and payment for the Stock.

                                                                              24

13. NOTICES. All statements, requests, notices and agreements hereunder shall be
in writing, and:

         (a) if to the Underwriter, shall be delivered or sent by mail, telex or
         facsimile transmission to Wachovia Capital Markets, LLC, Equity Capital
         Markets, 7 St. Paul Street, Baltimore, Maryland 21202, Attention: West
         Riggs (Fax: 443-263-6809), or to such other address as Wachovia may
         designate in writing to the Company; and

         (b) if to the Company shall be delivered or sent by mail, telex or
         facsimile transmission to Encysive Pharmaceuticals Inc., 6700 West
         Loop, 4th Floor, Bellaire, Texas 77401, Attention: Bruce D. Given, M.D.
         (Fax: 713-796-8232).

14. DEFINITION OF CERTAIN TERMS. For purposes of this Agreement, (a) "business
day" means any day on which the New York Stock Exchange, Inc. is open for
trading and (b) "subsidiary" has the meaning set forth in Rule 405 of the Rules
and Regulations.

15. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

16. UNDERWRITER'S INFORMATION. The parties hereto acknowledge and agree that,
for all purposes of this Agreement, the Underwriter's Information consists
solely of the statements concerning the Underwriter contained in the fourth and
tenth paragraphs under the heading "Underwriting" in the Company's Prospectus
Supplement dated September 8, 2004.

17. PARTIAL UNENFORCEABILITY. The invalidity or unenforceability of any Section,
paragraph or provision of this Agreement shall not affect the validity or
enforceability of any other Section, paragraph or provision hereof. If any
Section, paragraph or provision of this Agreement is for any reason determined
to be invalid or unenforceable, there shall be deemed to be made such minor
changes (and only such minor changes) as are necessary to make it valid and
enforceable.

18. GENERAL. This Agreement constitutes the entire agreement of the parties to
this Agreement and supersedes all prior written or oral and all contemporaneous
oral agreements, understandings and negotiations with respect to the subject
matter hereof. In this Agreement, the masculine, feminine and neuter genders and
the singular and the plural include one another. The section headings in this
Agreement are for the convenience of the parties only and will not affect the
construction or interpretation of this Agreement. This Agreement may be amended
or modified, and the observance of any term of this Agreement may be waived,
only by a writing signed by the Company and the Underwriter.

19. COUNTERPARTS. This Agreement may be signed in any number of counterparts,
each of which shall be an original, with the same effect as if the signatures
thereto and hereto were upon the same instrument.

                                                                              25

         If the foregoing is in accordance with your understanding of the
agreement between the Company and the Underwriter, kindly indicate your
acceptance in the space provided for that purpose below.


                                   Very truly yours,

                                   ENCYSIVE PHARMACEUTICALS INC.


                                   By:     /s/ Stephen L. Mueller
                                        --------------------------------------
                                        Name:  Stephen L. Mueller
                                        Title: VP, Finance and Administration,
                                               Secretary and Treasurer


Accepted as of the date first above written:

WACHOVIA CAPITAL MARKETS, LLC

By: WACHOVIA CAPITAL MARKETS, LLC


By:     /s/ West Riggs
     -----------------------------
     Name:  West Riggs
     Title: Director



                                                                              26


                                   SCHEDULE A


Ron J. Anderson, M.D.

Tommy A. Brook, Ph.D.

J. Kevin Buchi

Frank C. Carlucci

Terrance C. Coyne, M.D.

Robert J. Cruikshank

Richard A.F. Dixon

Heather Giles, Ph.D.

Bruce D. Given, M.D.

Jeffrey Keyser

Pamela Mabry

Derek Maetzold

Stephen L. Mueller

Suzanne Oparil, M.D.

John M. Pietruski

Ann Tanabe

James A. Thomson, Ph.D.

Patrick Ward

James T. Willerson, M.D.

                                                                              27


                                    EXHIBIT I


                           [Form of Lock-Up Agreement]


                                                               September 8, 2004

Wachovia Capital Markets, LLC
301 South College Street, NC0610
Charlotte, NC  28288

Re:  Encysive Pharmaceuticals Inc. Shares of Common Stock

Dear Sirs:

         In order to induce Wachovia Capital Markets, LLC ("Wachovia") to enter
in to a certain underwriting agreement with Encysive Pharmaceuticals Inc., a
Delaware corporation (the "Company"), with respect to the public offering of
shares of the Company's common stock, par value $.005 per share ("Common
Stock"), the undersigned hereby agrees that for a period of 90 days following
the date of the final prospectus filed by the Company with the U.S. Securities
and Exchange Commission in connection with such public offering (the "Restricted
Period"), the undersigned will not, without the prior written consent of
Wachovia, directly or indirectly, (i) offer, sell, assign, transfer, pledge,
contract to sell, or otherwise dispose of, any shares of Common Stock
(including, without limitation, Common Stock which may be deemed to be
beneficially owned by the undersigned in accordance with the rules and
regulations promulgated under the Securities Act of 1933, as the same may be
amended or supplemented from time to time (such shares, the "Beneficially Owned
Shares")) or securities convertible into or exercisable or exchangeable in
Common Stock, (ii) enter into any swap, hedge or similar agreement or
arrangement that transfers in whole or in part, the economic risk of ownership
of the Beneficially Owned Shares or securities convertible into or exercisable
or exchangeable in Common Stock or (iii) engage in any short selling of the
Common Stock[; provided, however, that notwithstanding the foregoing, the
undersigned may sell up to an aggregate of * shares of Common Stock within such
90-day period without the prior written consent of Wachovia upon prior notice to
Wachovia].

         If:

         (1) during the last 18 days of the Restricted Period, the Company
issues an earnings release; or

         (2) prior to the expiration of the Restricted Period, the Company
announces that it will release earnings results during the 16-day period
beginning on the last day of the Restricted Period, the restrictions set forth
herin shall continue to apply until the expiration of the 19-day period
beginning on the issuance of the earnings release.

         Anything contained herein to the contrary notwithstanding, any person
to whom shares of Common Stock or Beneficially Owned Shares are transferred from
the undersigned shall be bound by the terms of this Agreement.

         In addition, the undersigned hereby waives, from the date hereof until
the expiration of the Restricted Period, any and all rights, if any, to request
or demand registration pursuant to the Securities Act of 1933, as the same may
be amended or supplemented from time to time, of any shares of Common




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

* As agreed with Wachovia.


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Stock that are registered in the name of the undersigned or that are
Beneficially Owned Shares. In order to enable the aforesaid covenants to be
enforced, the undersigned hereby consents to the placing of legends and/or
stop-transfer orders with the transfer agent of the Common Stock with respect to
any shares of Common Stock or Beneficially Owned Shares.

                                              [Signatory]


                                              By:
                                                 -------------------------------
                                                 Name:
                                                 Title: