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                                                                    EXHIBIT 99.2

                            STOCK PURCHASE AGREEMENT


         THIS STOCK PURCHASE AGREEMENT (the "Agreement") is made as of the 29th
day of December, 2000, by and between Atrix Laboratories, Inc., a Delaware
corporation having offices at 2579 Midpoint Drive, Fort Collins, CO 80525-4417
(the "Company"), and Sanofi-Synthelabo Inc., a Delaware corporation having
offices at 90 Park Avenue, New York, NY 10016 ("Investor").

         THE PARTIES HEREBY AGREE AS FOLLOWS:

1.       Purchase and Sale of Stock.

         1.1.     Sale and Issuance of Common Stock. Subject to the terms and
                  conditions of this Agreement, at the Closing (defined below)
                  Investor will purchase and the Company will sell and issue to
                  Investor 824,572 shares of Common Stock (the "Shares") for the
                  purchase price per share equal to $18.19125, which is one
                  hundred and ten percent (110%) of the average of the closing
                  prices reported by the NASDAQ National Market System for the
                  ten (10) consecutive trading days prior to, but not including,
                  the Closing Date, for an aggregate purchase price of Fourteen
                  Million Nine Hundred Ninety-Nine Thousand Nine Hundred and
                  Ninety-Five Dollars and Forty Cents ($14,999,995.40) (the
                  "Purchase Price").

         1.2.     Closing. The purchase and sale of the Common Stock shall take
                  place at the offices of the Company, 2579 Midpoint Drive, Fort
                  Collins, Colorado 80525, on the "Effective Date", as such term
                  is defined in the Collaboration, License and Supply Agreement
                  of even date herewith between the parties hereto (the
                  "Collaboration Agreement"), or at such other times and places
                  as the Company and Investor mutually agree upon in writing
                  (which times and places are designated as the "Closing"). At
                  the Closing, the Company shall deliver to its transfer agent,
                  American Stock Transfer & Trust Company, a letter, in the form
                  of Exhibit A, which letter directs American Stock Transfer &
                  Trust Company to deliver promptly to Investor a certificate
                  representing the Shares.

         1.3.     Purchase Price. At the Closing, the Purchase Price shall be
                  paid by Investor to the Company in immediately available funds
                  by wire transfer to a bank account designated by the Company
                  two (2) business days prior to the Closing Date or, if not so
                  designated, then by certified or official bank check payable
                  in immediately available funds to the order of the Company in
                  such amount.

1.4.     Definition.

                           (a)      The following terms, as used herein, have
                                    the following meanings:

                                    "Affiliate" shall have the meaning defined
                                    in Rule 501 of Regulation D as promulgated
                                    under the 1933 Act.

                                    "Closing Date" means the date of the
                                    Closing.
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                                    "Common Stock" means the Common Stock, par
                                    value $.001 per share of the Company.

                                    "GAAP" means generally accepted accounting
                                    principles in the United States.

                                    "Material Adverse Effect" means a material
                                    adverse effect on the condition (financial
                                    or otherwise), business, assets, results of
                                    operations of a corporation and its
                                    subsidiaries taken as a whole.

                                    "1934 Act" means the Securities Exchange Act
                                    of 1934, as amended, and the rules and
                                    regulations promulgated thereunder.

                                    "1933 Act" means the Securities Act of 1933,
                                    as amended, and the rules and regulations
                                    promulgated thereunder.

                                    "Person" shall mean an individual,
                                    corporation, partnership, trust, business
                                    trust, association, joint stock company,
                                    joint venture, pool, syndicate, sole
                                    proprietorship, and any other form of entity
                                    not specifically listed herein.

                                    "SEC" shall mean the U.S. Securities and
                                    Exchange Commission.

2.       Representations and Warranties of the Company. The Company hereby
         represents and warrants to Investor that:

         2.1.     Organization, Good Standing and Qualification. The Company is
                  a corporation duly organized, validly existing and in good
                  standing under the laws of the State of Delaware and has all
                  requisite corporate power and authority to carry on its
                  business as now conducted. The Company is duly qualified to
                  transact business and is in good standing in each jurisdiction
                  in which the failure to so qualify would have a Material
                  Adverse Effect.

         2.2.     Capitalization. The authorized capital of the Company consists
                  of:

                  (a)      Preferred Stock. 5,000,000 shares of Preferred Stock,
                           of which (i) 200,000 shares have been designated
                           Series A Preferred Stock, par value $.001 per share,
                           none of which are issued and outstanding; (ii) 20,000
                           shares have been designated Series A Convertible
                           Exchangeable Preferred Stock, par value $.001 per
                           share, of which 12,015 shares were issued and
                           outstanding on December 29, 2000; and (iii) 4,780,000
                           shares are undesignated, none of which are issued and
                           outstanding.

                  (b)      Common Stock. 25,000,000 shares of Common Stock, of
                           which 12,555,120 shares were issued and outstanding
                           on December 29, 2000.

         2.3.     Authorization. All corporate action on the part of the
                  Company, its officers, directors and stockholders necessary
                  for (i) its authorization, execution and


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                  delivery of the Agreement, (ii) the performance of all
                  obligations of the Company hereunder and (iii) the
                  authorization, issuance (or reservation for issuance) and
                  delivery of the Common Stock being sold hereunder, to the
                  extent that the foregoing requires performance on or prior to
                  the Closing, has been taken. This Agreement, assuming due
                  authorization, execution and delivery by Investor, constitutes
                  the valid and legally binding obligation of the Company,
                  enforceable against the Company in accordance with its terms,
                  except as such enforcement may be limited by applicable laws
                  relating to creditors' rights or principles of equity
                  affecting the availability of remedies.

         2.4.     Valid Issuance of Common Stock. The Shares, when issued
                  against payment thereof in accordance with this Agreement,
                  will be duly and validly issued, fully paid and nonassessable
                  and, based in part upon the representations of the Investor in
                  this Agreement, will be issued in compliance with all
                  applicable federal and state securities laws.

         2.5.     SEC Filings. The Company has registered its Common Stock
                  pursuant to Section 12 of the 1934 Act, and the Common Stock
                  is quoted on the Nasdaq National Market. The Company has filed
                  all 1934 Act reports for a period of at least twelve (12)
                  months immediately preceding the offer or sale of the Shares.
                  The Company's filings with the SEC complied as of their
                  respective filing dates, or in the case of registration
                  statements, their respective effective dates, as to form in
                  all material respects with all applicable requirements of the
                  1933 Act and the 1934 Act and the rules and regulations
                  promulgated thereunder. None of such filings, including,
                  without limitation, any exhibits, financial statements or
                  schedules included therein, at the time filed, or in the case
                  of registration statements, at their respective filing dates,
                  contained any untrue statement of a material fact or omitted
                  to state a material fact required to be stated therein or
                  necessary to make the statements therein, in light of the
                  circumstances under which they were made, not misleading. The
                  audited financial statements of the Company included in the
                  Company's Annual Report on Form 10-K for the year ended
                  December 31, 1999 comply as to form in all material respects
                  with the published rules and regulations of the SEC with
                  respect thereto, and such audited financial statements (i)
                  were prepared from the books and records of the Company, (ii)
                  were prepared in accordance with GAAP applied on a consistent
                  basis (except as may be indicated therein or in the notes or
                  schedules thereto) and (iii) present fairly the financial
                  position of the Company as of the dates thereof and the
                  results of operations and cash flows for the periods then
                  ended. The unaudited financial statements included in the
                  Company's Quarterly Reports on Form 10-Q for the quarterly
                  periods ended March 31, 2000, June 30, 2000 and September 30,
                  2000 comply as to form in all material respects with the
                  published rules and regulations of the SEC with respect
                  thereto; and such unaudited financial statements (i) were
                  prepared from the books and records of the Company, (ii) were
                  prepared in accordance with GAAP, except as otherwise
                  permitted under the 1934 Act and the rules and regulations
                  thereunder, on a consistent basis (except as may be indicated
                  therein or in the notes or schedules thereto, and except that
                  they do not contain footnotes and other presentation items


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                  that may be required by GAAP) and (iii) present fairly the
                  financial position of the Company as of the dates thereof and
                  the results of operations and cash flows (or changes in
                  financial condition) for the periods then ended, subject to
                  normal year-end adjustments and any other adjustments
                  described therein or in the notes or schedules thereto.

         2.6.     Litigation. Except as disclosed in the Company's filings with
                  the SEC, there is no action, suit or proceeding before or by
                  any court or governmental agency or body, domestic or foreign,
                  now pending or, to the knowledge of the Company, threatened,
                  against or affecting the Company, or any of its properties,
                  which could reasonably be expected to have, individually or in
                  the aggregate, a Material Adverse Effect.

         2.7.     No Default. Except as disclosed in the Company's filings with
                  the SEC, the Company is not in default in the performance or
                  observance of any material obligation, agreement, covenant or
                  condition contained in any indenture, mortgage, deed of trust
                  or other material agreement or instrument to which it is a
                  party or by which it or its property may be bound and which is
                  filed as an exhibit to the Company's 1934 Act reports, except
                  for defaults that have not had and would not reasonably be
                  expected to have, individually or in the aggregate, a Material
                  Adverse Effect.

         2.8.     Subsequent Events; Undisclosed Liabilities. Since September
                  30, 2000, the Company has not incurred any liability or
                  obligation, contingent or otherwise, that taken as a whole, is
                  material in the aggregate to the Company, except (i) in the
                  ordinary course of business consistent with past practices, or
                  (ii) as reflected in or reserved against in the balance sheet
                  of the Company as of September 30, 2000. Since September 30,
                  2000, the Company has conducted its business in the ordinary
                  course of business consistent with past practices, and there
                  has not been any Material Adverse Effect and there is no
                  condition existing that could reasonably be expected to result
                  in a Material Adverse Effect on the business of the Company.

         2.9.     Consents and Approvals. No material consent, approval,
                  qualification, order or authorization of, or filing with, any
                  local, state or federal governmental authority or any third
                  party, including any approval under the Hart-Scott-Rodino
                  Antitrust Improvements Act of 1976, as amended, is required on
                  the part of the Company in connection with the Company's valid
                  execution, delivery or performance of this Agreement, or the
                  offer, sale or issuance of the Shares by the Company, other
                  than the filings that have been made prior to the Closing,
                  except that any notices of sale required to be filed by the
                  Company with the SEC under Regulation D of the 1933 Act and
                  filings required by the rules of the Nasdaq National Market,
                  or such post-closing filing as may be required under
                  applicable state securities laws, which will be timely filed
                  within the applicable periods therefor.

         2.10.    Compliance with Laws and Court Orders. The Company is not in
                  violation of any applicable law, rule, regulation, judgment,
                  injunction, order or decree except for


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                  violations that have not had and would not reasonably be
                  expected to have, individually or in the aggregate, a Material
                  Adverse Effect.

         2.11.    No Conflict. The execution and delivery of this Agreement and
                  the Company's performance of its obligations under this
                  Agreement will not (i) violate any applicable law, ordinance,
                  rule or regulation of any governmental authority or (ii)
                  conflict with or result in a breach of the terms and
                  conditions of, or constitute any default under, the Company's
                  Certificate of Incorporation or By-laws, or any contract,
                  agreement or instrument to which the Company or any subsidiary
                  is a party or by which the Company or any Subsidiary or any of
                  their respective property if bound, except, in any such case,
                  for violations, conflicts or breaches which individually or in
                  the aggregate would not have a Material Adverse Effect.

         2.12.    Insurance. The Company has in full force and effect fire and
                  casualty, general liability and product liability insurance
                  policies, with extended coverage, in amounts customary for
                  companies similarly situated to the Company.

         2.13.    Environmental and Safety Laws. The Company is not in violation
                  of any applicable statute, law or regulation relating to the
                  environment or occupational health and safety, except where
                  such violation could not reasonably be expected to have a
                  Material Adverse Effect, and to the best of its knowledge, no
                  material expenditures are or will be required in order to
                  comply with any such existing statute, law or regulation.

         2.14.    Legal Proceedings, Etc. There is no legal, administrative,
                  arbitration or other action or proceeding or governmental
                  investigations pending, or to the Company's knowledge
                  threatened, against the Company which could reasonably be
                  expected to result in the issuance of an order restraining,
                  enjoining or otherwise prohibiting or making illegal the
                  consummation of any of the transactions contemplated by this
                  Agreement.

3.       Representations and Warranties of Investor. Investor hereby represents
         and warrants to the Company that:

         3.1.     Organization and Existence. Investor is a corporation duly
                  incorporated, validly existing and in good standing under the
                  laws of Delaware and has all requisite corporate power and
                  authority to carry on its business as now conducted.

         3.2.     Corporate Authorization. Investor has full corporate power and
                  authority to execute and deliver this Agreement and perform
                  its obligations hereunder. The execution, delivery and
                  performance by Investor of this Agreement have been duly
                  authorized by all requisite corporate action. This Agreement,
                  assuming due authorization, execution and delivery by the
                  Company, constitutes the valid and legally binding obligation
                  of Investor, enforceable against Investor in accordance with
                  its terms, except as such enforcement may be limited by
                  applicable laws relating to creditors' rights or principles of
                  equity affecting the availability of remedies.


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         3.3.     Purchase Entirely for Own Account. Investor is sophisticated
                  in transactions of this type and capable of evaluating the
                  merits and risks of the transactions described herein, and has
                  the capacity to protect its own interests. Investor has not
                  been formed solely for the purpose of entering into the
                  transactions described herein. The Shares to be received by
                  Investor will be acquired for investment for Investor's own
                  account, not as a nominee or agent, and not with a view to the
                  resale or distribution of any part thereof, and that Investor
                  has no present intention of selling, granting any
                  participation in, or otherwise distributing the same. By
                  executing this Agreement, Investor further represents that
                  Investor does not have any contract, undertaking, agreement or
                  arrangement with any person to sell, transfer or grant
                  participation to such person or to any third person, with
                  respect to any of the Shares.

         3.4.     Restricted Securities. Investor understands that the shares of
                  Common Stock it is purchasing are characterized as "restricted
                  securities" under the federal securities laws inasmuch as they
                  are being acquired from the Company in a transaction not
                  involving a public offering and that under such laws and
                  applicable regulations such securities may be resold without
                  registration under the 1933 Act only under certain limited
                  circumstances. In this connection Investor represents that it
                  is familiar with SEC Rule 144, as presently in effect, and
                  understands the resale limitations imposed thereby and by the
                  1933 Act.

                  Investor agrees that it shall not sell or otherwise transfer
                  any of the Shares without registration under the 1933 Act, or
                  pursuant to Rule 144 under the 1933 Act, or pursuant to an
                  opinion of counsel reasonably satisfactory to the Company that
                  an exemption from registration is available, and fully
                  understands and agrees that it must bear the total economic
                  risk of its purchase for an indefinite period of time because
                  of the restricted nature of the Shares. Investor understands
                  that the Company is under no obligation to register the Shares
                  on its behalf. Investor understands the lack of liquidity and
                  restrictions on transfer of the Shares and that this
                  investment is suitable only for a person or entity of adequate
                  financial means that has no need for liquidity of this
                  investment and that can afford a total loss of its investment.

         3.5.     Legends. Investor acknowledges that the certificates
                  evidencing the Shares shall bear the following or
                  substantially similar legend or such other legends as may be
                  required by state or other applicable securities laws:

                           "THE SHARES EVIDENCED BY THIS CERTIFICATE HAVE NOT
                           BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
                           AMENDED (THE "ACT"), OR THE SECURITIES ACT OF ANY
                           STATE. THE SHARES MAY NOT BE SOLD, TRANSFERRED FOR
                           VALUE, PLEDGED, HYPOTHECATED OR OTHERWISE ENCUMBERED
                           IN THE ABSENCE OF AN EFFECTIVE REGISTRATION OF THEM
                           UNDER THE ACT AND/OR THE SECURITIES ACT OF ANY STATE
                           OR IN THE ABSENCE OF AN OPINION OF COUNSEL ACCEPTABLE
                           TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED
                           UNDER SUCH ACT OR ACTS."


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         3.6.     Removal of Legends

                  (a)      Any legend endorsed on a certificate pursuant to
                           Section 3.5 shall be removed (i) if the shares of
                           Common Stock represented by such certificate shall
                           have been resold under an effective registration
                           statement under the 1933 Act or otherwise lawfully
                           sold in a public transaction, (ii) if such shares may
                           be transferred in compliance with Rule 144
                           promulgated under the 1933 Act, or (iii) if the
                           holder of such shares shall have provided the Company
                           with an opinion of counsel, in form and substance
                           acceptable to the Company and its counsel, stating
                           that a public sale, transfer or assignment of such
                           shares may be made without registration.

                  (b)      Any legend endorsed on a certificate as required by
                           state securities laws pursuant to Section 3.5 shall
                           be removed if the Company receives an order of the
                           appropriate state authority authorizing such removal
                           or if the holder of such shares provides the Company
                           with an opinion of counsel, in form and substance
                           acceptable to the Company and its counsel, stating
                           that such state legend may be removed.

         3.7.     Accredited Investor. Investor is an "accredited investor" (as
                  defined in Rule 501(a) under the 1933 Act) and has the
                  financial ability to bear the economic risks of its
                  investment, has adequate means for providing for its current
                  needs and contingencies and has no need for liquidity with
                  respect to its investment in the Company.

         3.8.     Consents and Approvals. Except for Schedule 13D or 13G under
                  the Securities Exchange Act of 1934, no material consent,
                  approval, qualification, order or authorization of, or filing
                  with, any local, state or federal governmental authority or
                  any third party, including any approval under the
                  Hart-Scott-Rodino Antitrust Improvements Act of 1976, as
                  amended, is required on the part of the Investor in connection
                  with the Investor's valid execution, delivery or performance
                  of this Agreement.

         3.9.     Legal Proceedings, Etc. There is no legal, administrative,
                  arbitration or other action or proceeding or governmental
                  investigations pending, or to the Investor's knowledge
                  threatened against the Investor which could reasonably be
                  expected to result in the issuance of an order restraining,
                  enjoining or otherwise prohibiting or making illegal the
                  consummation of any of the transactions contemplated by this
                  Agreement.

         3.10.    Availability of Funds. Investor has or will have available at
                  Closing, sufficient funds to pay the Purchase Price for the
                  Shares.

         3.11.    Ultimate Parent Entity. Sanofi-Synthelabo, a societe anonyme,
                  organized under the laws of France, is the ultimate parent
                  entity (as defined in 16 C.F.R. Section


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                  801.1(a)(3) and (b)) of Investor and Sanofi-Synthelabo
                  (societe anonyme), together with all entities it controls (as
                  defined in 16 C.F.R. Section 801.1(b)), does not presently
                  hold any voting securities of the Company.

4.       Covenant relating to Rule 144. The Company will file reports in
         compliance with the 1934 Act, will comply with all rules and
         regulations of the Commission applicable in connection with the use of
         Rule 144 and take such other actions and furnish the Investor with such
         other information as the Investor may request in order to avail itself
         of such rule or any other rule or regulation of the Commission allowing
         Investor to sell any Company Shares without registration, and will, at
         its own expense, upon the request of the Investor, deliver to the
         Investor a certificate, signed by the Company's principal financial
         officer, stating (a) the Company's name, address and telephone number
         (including area code), (b) the Company's Internal Revenue Service
         identification number, (c) the Company's Commission file number, (d)
         the number of shares of each class of stock outstanding as shown by the
         most recent report or statement published by the Company, and (e)
         whether the Company has filed the reports required to be filed under
         the 1934 Act for a period of at least ninety (90) days prior to the
         date of such certificate and in addition has filed the most recent
         annual report required to be filed thereunder. If at any time the
         Company is not required to file reports in compliance with either
         Section 13 or Section 15(d) of the 1934 Act, the Company at its expense
         will, upon the written request of the Investor, make available adequate
         current public information with respect to the Company within the
         meaning of paragraph (c)(2) of Rule 144.

5.       Lock-Up. Notwithstanding anything to the contrary contained in this
         Agreement, Investor shall not sell, contract to sell, grant any option
         to purchase, transfer the economic risk of ownership in, make any short
         sale of, pledge or otherwise transfer or dispose of (collectively,
         "Sell") any Shares for a period of one (1) year after the Closing Date.
         Further, Investor agrees that during any three-month period following
         the first anniversary of the Closing Date and prior to the second
         anniversary of the Closing Date, it will only Sell up to an aggregate
         of twenty-five percent (25%) of the Shares; provided, however, that
         Investor agrees that it will notify the Company prior to taking any
         action to Sell and in any event will not Sell, within one (1) trading
         day, in one or a series of related transactions, Shares constituting
         more than twenty percent (20%) of the average daily trading volume of
         the Common Stock over the twenty (20) trading days immediately
         preceding such trading day. Investor further agrees, in the event of a
         public offering by the Company of Common Stock on a Registration
         Statement on Form S-1, S-2, S-3 or S-4, not to Sell Shares for a period
         of ninety (90) days from the date Investor receives notice from the
         Company that the Company has filed or intends to file within thirty
         (30) days a registration statement with respect to the Company's Common
         Stock with the United States Securities and Exchange Commission. The
         above limitation shall not apply with respect to more than two (2)
         public offerings of Common Stock by the Company.

6.       Conditions to Closing.

         6.1.     Conditions of Investor to Closing; Deliveries to Investor. The
                  obligations of Investor to consummate the transactions
                  contemplated by this Agreement are


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                  subject to the satisfaction, at or prior to the Closing, of
                  each of the following conditions:

                  (a)      A certificate from a duly authorized officer of the
                           Company certifying that the representations and
                           warranties of the Company set forth in this Agreement
                           shall be true and correct as of the Closing Date as
                           if made on and as of the Closing Date.

                  (b)      The Collaboration Agreement shall have concurrently
                           closed.

                  (c)      Investor shall have received the following documents
                           or deliveries at or before the Closing, each of which
                           shall be in full force and effect:

                           (i) evidence of the delivery of the letter to the
                  Company's transfer agent pursuant to Section 1.2 above; and

                           (ii) a certificate signed by the chief executive
                  officer and the corporate secretary of the Company certifying
                  (x) to resolutions duly and validly adopted by the Board of
                  Directors of the Company evidencing and its authorization of
                  the execution and delivery of this Agreement and the issuance
                  of the Shares to Investor, and the consummation of the
                  transactions contemplated hereby and that such resolutions
                  have not been amended and remain in full force and effect, and
                  (y) to the names and signatures of the persons authorized on
                  behalf of the Company to execute and deliver this Agreement.

         6.2.     Conditions of the Company to Closing; Deliveries to the
                  Company. The obligations of the Company to consummate the
                  transactions contemplated by this Agreement are subject to the
                  satisfaction, at or prior to the Closing, of each of the
                  following conditions:

                  (a)      A certificate from a duly authorized officer of
                           Investor certifying that the representations and
                           warranties of Investor set forth in this Agreement
                           shall be true and correct as of the Closing Date as
                           if made on and as of the Closing Date.

                  (b)      The Collaboration Agreement shall have concurrently
                           closed.

                  (c)      The Company shall have received the following
                           documents or deliveries at or before the Closing,
                           each of which shall be in full force and effect:

                           (i) a certificate signed by the chief executive
                  officer and the corporate secretary of Investor certifying (x)
                  to resolutions duly and validly adopted by the Board of
                  Directors of Investor evidencing and its authorization of the
                  execution and delivery of this Agreement and the consummation
                  of the transactions contemplated hereby and that such
                  resolutions have not been amended and remain in full force and
                  effect, and (y) to the names and signatures of the persons
                  authorized on behalf of Investor to execute and deliver this
                  Agreement; and


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                           (ii) the consideration payable by Investor at Closing
                  as provided in Section 1.3 in immediately available funds.

7.       Termination.

         7.1.     Termination. This Agreement may be terminated prior to the
                  Closing:

                  (a)      By mutual written consent of the Company and
                           Investor.

                  (b)      In the event that the Collaboration Agreement shall
                           not have concurrently closed.

         7.2.     Effect of Termination. In the event of the termination of this
                  Agreement as provided in Section 7.1, this Agreement shall be
                  of no further force or effect; provided, however that the
                  termination of this Agreement shall not relieve any party from
                  any liability for any willful and knowing breach of this
                  Agreement.

8.       Miscellaneous.

         8.1.     Successors and Assigns. This Agreement may not be assigned
                  without the prior written consent of the non-assigning party;
                  provided, however, that without prior written approval,
                  Investor may assign any and all of its rights and interest
                  under this Agreement to one or more of its Affiliates and
                  designate one or more of its Affiliates to perform its
                  obligations under this Agreement; provided such Affiliate
                  expressly acknowledges and confirms the representations,
                  warranties and information set forth in Sections 3.4, 3.5 and
                  3.7 of this Agreement. Any purported assignment in violation
                  of this provision shall be null and void. The terms and
                  conditions of this Agreement shall inure to the benefit of and
                  be binding upon the respective permitted successors and
                  assigns of the parties. Nothing in this Agreement, express or
                  implied, is intended to confer upon any party other than the
                  parties hereto or their respective successors and assigns any
                  rights, remedies, obligations, or liabilities under or by
                  reason of this Agreement, except as expressly provided in this
                  Agreement.

         8.2.     Third Party Purchaser. A third-party purchaser of the Shares
                  from Investor will not be subject to any of the terms of this
                  Agreement other than those imposed by the federal and state
                  securities laws.

         8.3.     Governing Law. This Agreement shall be governed by and
                  construed under the laws of the State of New York
                  (irrespective of its choice of law principles).

         8.4.     Counterparts. This Agreement may be executed in two or more
                  counterparts, each of which shall be deemed an original, but
                  all of which together shall constitute one and the same
                  instrument.

         8.5.     Titles and Subtitles. The titles and subtitles used in this
                  Agreement are used for convenience only and are not to be
                  considered in construing or interpreting this Agreement.


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         8.6.     Notices. All notices, requests and other communications to any
                  party hereunder shall be in writing (including facsimile
                  transmission) and shall be deemed to have been given if
                  delivered personally, mailed by certified mail (return receipt
                  requested) or sent by cable, telegram, telecopier or
                  recognized overnight delivery service to the parties at the
                  following addresses or at such other addresses as specified by
                  the parties by like notice:

                           If to the Company:

                           Atrix Laboratories, Inc.
                           2579 Midpoint Drive
                           Fort Collins, Colorado 80525
                           Attn:  Dr. Charles P. Cox, Vice President of
                                  New Business Development
                           Fax:   (970) 482-9765
                           Phone: (970) 482-5868

                           With a copy to:

                           Morrison & Foerster LLP
                           370 17th Street, Suite 5200
                           Denver, Colorado 80202
                           Attn:  Warren L. Troupe, Esq.
                           Fax:   (303) 592-1510
                           Phone: (303) 592-1500

                           If to Investor:

                           Sanofi-Synthelabo Inc.
                           90 Park Avenue
                           New York, NY 10016
                           Attn:  Gregory Irace
                           Vice President and Chief Financial Officer
                           Telephone: (212) 551-4000
                           Facsimile: (212) 551-4905

                           With a copy to:

                           Sanofi-Synthelabo Inc.
                           90 Park Avenue
                           New York, New York 10016
                           Attn:  General Counsel
                           Telephone:  (212) 551-4306
                           Facsimile:  (212) 551-4919

                  Notice so given shall be deemed given and received (i) if by
                  mail on the fourth calendar day after posting; (ii) by cable,
                  telegram, telecopier, telex of personal


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                  delivery on the date of actual transmission or (as the case
                  may be) personal or other delivery; and (iii) if by overnight
                  courier, on the next business day following the day such
                  notice is delivered to the courier service.

         8.7.     Finders Fee. Each party represents that it neither is nor will
                  be obligated for any finders' fee or commission in connection
                  with this transaction. Investor agrees to indemnify and hold
                  harmless the Company from any liability for any commission or
                  compensation in the nature of a finders' fee (and costs and
                  expenses of defending against such liability or asserted
                  liability) for which Investor or any of its officers,
                  partners, employees or representatives is responsible. The
                  Company agrees to indemnify and hold harmless Investor from
                  any liability for any commission or compensation in the nature
                  of a finders' fee (and the costs and expenses of defending
                  against such liability or asserted liability) for which the
                  Company or any of its officers, employees or representatives
                  is responsible.

         8.8.     Expenses. The Company and the Investor shall pay their
                  respective costs and expenses incurred with respect to the
                  negotiation, execution, delivery and performance of this
                  Agreement.

         8.9.     Amendments and Waivers. Any term of this Agreement may be
                  amended and the observance of any term of this Agreement may
                  be waived (either generally or in a particular instance and
                  either retroactively or prospectively), only with the written
                  consent of the Company and the Investor. Any amendment or
                  waiver effected in accordance with this paragraph shall be
                  binding on the Investor and the Company.

         8.10.    Severability. If one or more provisions of this Agreement are
                  held to be unenforceable under applicable law, such provision
                  shall be excluded from this Agreement and the balance of this
                  Agreement shall be interpreted as if such provision were so
                  excluded and shall be enforceable in accordance with its
                  terms.

         8.11.    Entire Agreement. This Agreement constitutes the entire
                  agreement between the parties with respect to the subject
                  matter hereof and supersedes all prior agreements and
                  understandings, both oral and written, between the parties
                  with respect to the subject matter hereof. No representation,
                  inducement, promise, understanding, condition or warranty not
                  set forth herein has been made or relied upon by either party
                  intended to confer upon any person other than the parties
                  hereto any rights or remedies hereunder.

         8.12.    Other Agreements. The Company will not enter into any other
                  agreement with respect to its securities which violates the
                  rights granted to the Investor in this Agreement.


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         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.



ATRIX LABORATORIES, INC.                  SANOFI-SYNTHELABO INC.
a Delaware corporation                    a Delaware corporation

By: /s/ David R. Bethune                  By: /s/ John M. Spinnato
   ----------------------------------        ----------------------------------
Name:  David R. Bethune                   Name:  John M. Spinnato
Title: Chairman and Chief                 Title: Senior Vice President and
       Executive Officer                         General Counsel


                                          SANOFI-SYNTHELABO INC.
                                          a Delaware corporation

                                          By: /s/ Richard H. Thomson
                                             ----------------------------------
                                          Name:  Richard H. Thomson
                                          Title: Vice President and Treasurer


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                                    EXHIBIT A

                     LETTERHEAD OF ATRIX LABORATORIES, INC.



                                December __, 2000


American Stock Transfer & Trust Company
Transfer Agent and Registrar
6201 15th Avenue
Brooklyn, NY 11219


Attention:
          -------------------------

                  Re:     Atrix Laboratories, Inc. - Share Issuance Instructions

Ladies and Gentlemen:

                  Atrix Laboratories, Inc., a Delaware corporation (the
"Company"), proposes to issue _______________ (__________) shares of its common
stock, par value $.001 per share (the "Common Stock") pursuant to a Stock
Purchase Agreement between the Company and Sanofi-Synthelabo Inc. The shares to
be issued have been duly authorized, and when issued will be validly
outstanding, fully paid and non-assessable.

                  1. You are hereby irrevocably authorized and directed, as the
Company's Transfer Agent and Registrar, to register and countersign, as an
original issue, one certificate representing an aggregate of _________ shares of
the Common Stock in the name of Sanofi-Synthelabo Inc.

                  2. You are further directed to deliver the above referenced
share certificate to the following address, by registered mail:

                           Sanofi-Synthelabo Inc.
                           90 Park Avenue
                           New York, NY 10016
                           Attn:  Gregory Irace
                           Vice President and Chief Financial Officer

                  3.  The above-referenced certificate shall bear the following
legend:

                  "THE SHARES EVIDENCED BY THIS CERTIFICATE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR THE
SECURITIES ACT OF ANY STATE. THE SHARES MAY NOT BE SOLD, TRANSFERRED FOR VALUE,
PLEDGED, HYPOTHECATED OR OTHERWISE ENCUMBERED IN THE ABSENCE OF AN EFFECTIVE
REGISTRATION OF THEM


                                      A-1


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UNDER THE ACT AND/OR THE SECURITIES ACT OF ANY STATE OR IN
THE ABSENCE OF AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH
REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR ACTS."



            Please acknowledge receipt of these instructions below.

                                   Very truly yours,



                                   By:
                                      ------------------------------------------
                                   Name:    David R. Bethune
                                   Title:   Chairman and Chief Executive Officer



American Stock Transfer & Trust Company
as Transfer Agent and Registrar



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


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