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                                                                   EXHIBIT 10.13


                        CONFIDENTIAL TREATMENT REQUESTED

     Confidential Portions Of This Agreement Which Have Been Redacted Are Marked
With Brackets ([***]).  The Omitted Material Has Been Filed Separately With The
Securities And Exchange Commission.


                            PRODUCT SUPPLY AGREEMENT

     THIS PRODUCT SUPPLY AGREEMENT (the "Agreement") is entered into as of
January 29, 1999 (the "Effective Date"), by and between AMERICAN HOME PRODUCTS
CORPORATION, located at Five Giralda Farms, Madison, New Jersey 07940
(hereinafter "AHP"), and HORIZON PHARMACEUTICAL CORPORATION located at 660
Hembree Parkway, Suite 106, Roswell, Georgia 30076 (hereinafter "Horizon"). AHP
and Horizon may each be referred to herein individually as a "Party" and
collectively as the "Parties."

     WHEREAS, on January 29, 1999 Horizon and AHP entered into a license
agreement concerning AHP's grant of a license to Horizon of AHP's interest in
the Robinul(R) oral dosage form human pharmaceutical business in the United
States, its territories and possessions (including the Commonwealth of Puerto
Rico); and

     WHEREAS, Horizon desires AHP to manufacture or have manufactured and supply
to Horizon certain Robinul(R) products for sale by Horizon in the Territory (as
such term is defined below) and AHP desires to manufacture or have manufactured
and supply Horizon with such products on the terms and conditions set forth
herein.

     NOW THEREFORE, in consideration of the foregoing premises and the mutual
premises, covenants and conditions contained in this Agreement, the Parties
agree as follows:

1.   DEFINITIONS.

     As used in this Agreement, the following terms shall have the following
     respective meanings:

     1.1  "ACCEPTABLE PRODUCT" shall have the meaning set forth in Section 6.1
          hereof.

     1.2  "AFFILIATE" shall mean, in the case of either Party, any corporation,
          joint venture, or other business entity which directly or indirectly
          controls, is controlled by, or is under common control with that
          Party. "Control", as used in this Section 1.2, shall mean having the
          power to direct, or cause the direction of, the management and
          policies of an entity, whether

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through ownership of voting securities, by contract or otherwise.
Notwithstanding the foregoing, for purposes of this Agreement, the term
"Affiliate" shall not include subsidiaries in which a Party or its Affiliates
owns a majority of the ordinary voting power to elect a majority of the board of
directors but is restricted from electing such majority by contract or
otherwise, until such time as such restrictions are no longer in effect.

     1.3  "BINDING QUARTERLY FORECAST" shall have the meaning set forth in
          Section 2.3.1.

     1.4  "CALENDAR QUARTER" shall mean the respective periods of three (3)
          consecutive calendar months ending on March 31, June 30, September 30
          or December 31, for so long as this Agreement is in effect.

     1.5  "CERTIFICATE OF ANALYSIS" shall mean the certificate for each batch of
          Product delivered hereunder in the form contemplated by Section 2.6 of
          this Agreement.

     1.6  "CGMP" shall mean current good manufacturing practices of the FDA,
          including compliance with the FD&C Act, 21 C.F.R. parts 210 and 211
          and all applicable FDA rules, regulations, policies and guidelines in
          effect at a given time.

     1.7  "COMMERCIALLY REASONABLE EFFORTS" shall mean efforts and resources
          normally used by a Party for a compound or product owned by it or to
          which it has rights, which is of similar market potential at a similar
          stage in its product life, taking into account the competitiveness of
          the marketplace, the proprietary position of the compound or product,
          the regulatory structure involved, the profitability of the applicable
          products, and other relevant factors.

     1.8  "FDA" shall mean the United States Food and Drug Administration, and
          any successor thereto.

     1.9  "FD&C ACT" shall mean the United States Federal Food, Drug and
          Cosmetic Act, as amended.

     1.10 "FULLY ABSORBED COST" shall mean with respect to AHP's manufacture of
          the Product, the sum of AHP's standard unit costs of raw materials,
          direct labor and allocated overhead. The calculation of direct labor
          and allocated overhead costs will be consistent with AHP's then
          current cost accounting policies and procedures and in accordance with
          generally accepted accounting procedures.

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     1.11 "KNOW-HOW" shall mean all proprietary technical and clinical
          information, data and know-how relating to the manufacture of the
          Product, whether or not patentable, owned or controlled, as of the
          Effective Date or acquired during the term of this Agreement, by AHP
          or its Affiliates (with the right to have or disclose). Know-How shall
          include, without limitation, all processes, formulas, discoveries and
          inventions whether relating to biological, chemical, pharmacological,
          toxicological, pharmaceutical, physical and analytical safety, quality
          control and clinical data, including, without limitation, phase IV
          clinical study data. The term "Know-How", however, shall not include
          (i) any know-how, processes, information and data which is, as of the
          Effective Date or later becomes, generally available to the public or
          (ii) any general manufacturing know-how not specific to the Product.

     1.12 "LICENSE AGREEMENT" shall mean the License Agreement between AHP and
          Horizon relating to, among other things, the grant by AHP to Horizon
          of an exclusive license pertaining to certain of AHP's Robinul(R)
          Products within the Territory which License Agreement was executed on
          January 29, 1999.

     1.13 "MATERIALS" shall mean any or all Substances, inactive ingredients,
          excipients, components, labels, packaging materials and other
          consumable materials used in the manufacture of the Products,
          provided, however, that Materials shall not include any equipment used
          in the manufacture of the Products.

     1.14 "MG." shall mean milligrams.

     1.15 "NDA" shall mean a New Drug Application as defined in the FD&C Act and
          applicable regulations thereunder, as amended from time to time.

     1.16 "PRODUCTS" shall mean the following compositions and dosage forms
          containing Substance in the following amounts and supplied to Horizon
          pursuant to this Agreement:

                           Product A                 (Robinul(R))
                           Tablets
                           Glycopyrrolate
                           1 mg.
                           Supplied in:              Bottles of 100

                           Product B                 (Robinul(R) Forte)
                           Tablets
                           Glycopyrrolate
                           2 mg.
                           Supplied in:              Bottles of 100

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          In addition, Products shall include 1 mg. Tablets (Product C) and 2
          mg. Tablets (Product D) supplied in bulk but only for Horizon's
          requirements to self-package for sampling purposes.

          It is understood by the Parties hereto that the Products are to (a) be
          substantially similar to those Products currently manufactured and
          marketed by AHP in the Territory, (b) comply with the Specifications
          and (c) be sold under the trademark Robinul(R).

     1.17 "REGULATORY APPROVALS" shall mean all (i) authorizations by the
          appropriate Regulatory Authorities which are required for the
          manufacture (other than manufacturing facility licenses, approvals or
          authorizations), marketing, promotion, pricing and sale of the
          Products in the Territory, and (ii) investigational new drug
          applications permitting the clinical study of the Product in the
          Territory, each of which are owned by AHP or its Affiliates.

     1.18 "REGULATORY AUTHORITY" shall mean any national, supra-national,
          regional, state or local regulatory agency, department, bureau,
          commission, council or other governmental entity in the Territory
          involved in the granting of Regulatory Approval for the Product,
          including, without limitation, the FDA.

     1.19 "SPECIFICATIONS" shall mean specifications for or concerning the
          manufacturing, testing, and packaging of Products as set forth in the
          Regulatory Approvals for the Product and in Schedule 1.19 hereto, or
          as may be agreed upon by the Parties in writing from time to time.

     1.20 "SUBSTANCE" shall mean the chemical substance 3-[(cyclopentylhydroxy
          phenylacety1)oxy]-1, 1-dimethylpyrrolidinium bromide, otherwise known
          as glycopyrrolate.

     1.21 "TERM" shall have the meaning set forth in Section 10.1 hereof.

     1.22 "TERRITORY" shall mean the United States, its territories and
          possessions (including the Commonwealth of Puerto Rico).

     1.23 "THIRD PARTY(IES) shall mean any person(s) or party(ies) other than
          Horizon, AHP or their respective Affiliates.

     1.24 "TRANSACTION AGREEMENTS" shall mean this Agreement and the License
          Agreement.

     1.25 "$" shall mean United States dollars.

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2.   SUPPLY OF PRODUCTS.

     2.1  OBLIGATION TO SUPPLY. Subject to the provisions of this Agreement,
          during the Term of this Agreement, AHP shall manufacture or have
          manufactured for and supply to Horizon Products for sale by Horizon,
          its Affiliates or its permitted sublicensees in the Territory, and
          Horizon shall purchase from AHP its entire requirements of Products
          for sale in the Territory. All Products supplied under this Agreement
          are to be supplied in finished form, as specified in Horizon's
          purchase orders placed with AHP pursuant to Section 2.4 below.

     2.2  SUBCONTRACTING; ASSIGNMENT OF OBLIGATIONS.

          2.2.1RIGHT TO SUBCONTRACT OR ASSIGN. AHP may subcontract or assign any
               part of its manufacturing and supply obligations hereunder if it
               provides no less than six (6) months' written notice of its
               intent to do so to Horizon, subject to Horizon's prior right to
               take over such manufacturing and supply obligations. AHP and
               Horizon agree that, prior to transfer of manufacturing
               obligations to such subcontractor or assignee, such subcontractor
               or assignee must (i) have an FDA approved facility for the
               manufacture of Product and a supplement to the Regulatory
               Approvals permitting the manufacture of Product in such
               facilities must be approved by the FDA, and (ii) must agree in
               writing to comply with the obligations set forth in this
               Agreement. AHP shall assist in the qualification of such third
               party manufacturers or Horizon; provided, however, that AHP's
               assistance shall be limited to providing reasonable technical
               assistance not to exceed 30 man-days and the delivery of the
               following documentation: Batch records for both strengths of the
               Product, copies of change control history, all method validations
               (including new HPLC methods), active ingredient specification
               sheets, raw material test procedures, copies of process and
               cleaning validations, and a copy of the Product dossier made
               available to Horizon during the due diligence process. AHP shall
               notify Horizon or obtain Horizon's consent with respect to its
               purchase of Materials from qualified Third Parties for use in its
               manufacture of Product hereunder.

          2.2.2COSTS. In the event that (i) during the Term of this Agreement
               AHP subcontracts or assigns its manufacturing and supply
               obligations to a Third Party pursuant to Horizon's request or
               (ii) Horizon assumes, either directly or through a Third Party,
               the responsibilities for manufacturing and supplying Product
               during the Term of this Agreement as permitted under Section
               2.2.1 hereof, Horizon shall pay the out-of-pocket expenses
               incurred by either Party in transferring such manufacturing and
               supply responsibilities.

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     2.3  FORECASTS

          2.3.1ROLLING FORECASTS. Throughout the term of this Agreement, Horizon
               shall provide AHP with a rolling one (1) year forecast of its
               expected purchases of each Product, the mechanism for which shall
               be as follows:

          (i)  On or before the Effective Date, Horizon shall have provided AHP
               with a written forecast of its expected purchases of each of the
               Products for the period extending three (3) Calendar Quarters
               beyond the Calendar Quarter containing the Effective Date.
               Subject to Section 2.3.2, the forecast for this period, excluding
               the last two (2) Calendar Quarters, shall be binding upon
               Horizon.

          (ii) Beginning on the date of the first Calendar Quarter following the
               Effective Date and then on or prior to the first day of each
               subsequent Calendar Quarter, Horizon shall provide AHP with an
               update to its previously submitted forecast of its expected
               purchases of each of the Products. Such update shall consist of a
               repetition of the previously forecasted three (3) Calendar
               Quarters along with a newly introduced forecast for the Calendar
               Quarter subsequent to the last Calendar Quarter previously
               forecasted, provided, however, that the quantity forecasted for
               each Product for any Calendar Quarter shall not, without AHP's
               prior written consent, be more than one hundred twenty-five
               percent (125%) of the quantity forecasted for such Product for
               the immediately preceding Calendar Quarter. Subject to Section
               2.3.2, the forecast for this period, excluding the last two (2)
               Calendar Quarters, shall be binding upon Horizon.

          (iii)Under each of Sections 2.3.1(i) and 2.3.1(ii) above, the forecast
               for those quarters which is binding upon Horizon shall be a
               "Binding Quarterly Forecast."

          2.3.2QUANTITY LIMITATIONS. The quantity of each Product ordered by
               Horizon to be supplied by AHP in accordance with such orders in
               any Calendar Quarter shall not be less than seventy-five percent
               (75%) of the quantity of such Product specified in the most
               recent Binding Quarterly Forecast applicable to such Calendar
               Quarter. Additionally, AHP shall not be obligated to supply that
               quantity of any Product in any Calendar Quarter that is more than
               one hundred twenty-five percent (125%) of the quantity of such
               Product specified for the most recent Binding Quarterly Forecast
               applicable to such Calendar Quarter, but shall use its
               Commercially Reasonable Efforts to meet requirements in excess of
               such quantity. AHP shall provide sixty (60) days' written notice
               to Horizon in the event AHP determines that it cannot fill an
               order.
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     2.4  PURCHASE ORDERS

          2.4.1SUBMISSION OF PURCHASE ORDERS.  From time to time,  Horizon shall
               place  purchase  orders with AHP, in a format  agreed upon by the
               Parties, for each of the Products specifying the quantities of
               the Products desired, and the place(s) to which and the manner
               and dates by which delivery is to be made; said delivery dates to
               be no earlier than one hundred twenty (120) calendar days after
               the purchase order date. All purchase orders shall be sent by
               Horizon to the attention of the following employee of AHP or as
               otherwise instructed by AHP.

                          Wyeth-Ayerst Pharmaceuticals
                           P.O. Box 861
                           Paoli, PA 19301
                           Attn: Mr. Tom Higgins,
                                 Finished Stock Requirements Division
                           FAX:  (610) 651-3659

               Purchase orders made in accordance with the provisions of this
               Article 2 shall be deemed to be accepted by AHP if AHP has not
               rejected said purchase orders within ten (10) business days of
               receipt of the same, provided, however, that AHP shall not reject
               any purchase order specifying quantities within the quantity
               limitations set forth in Section 2.3.2 hereof and which purchase
               orders are otherwise in accordance with the provisions of this
               Article 2. To the extent the terms of any purchase order or
               acknowledgment thereof are inconsistent with the terms of this
               Agreement, the terms of this Agreement shall control.

          2.4.2SIZE OF ORDERS. All purchase orders for each Product placed by
               Horizon shall be whole number multiples of the production batch
               sizes used by AHP. These are set forth below (or as mutually
               agreed in writing by the Parties):

                   Product                   Batch Size - Expected Yield

                   Products A and C
                   1 mg. tablets                      [***] tablets

                   Products B and D
                   2 mg. tablets                      [***] tablets

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     2.5  DELIVERY. AHP shall execute all accepted purchase orders consistent
          with this Agreement by delivery ex works to Horizon's designated
          carrier at AHP's manufacturing or distribution facility of all ordered
          quantities of the Products no later than the delivery dates provided
          in Horizon's purchase orders. Title and risk of loss will pass to
          Horizon when each order of Products is delivered to the designated
          carrier of Horizon at AHP's manufacturing or distribution facility.

     2.6  SPECIFICATIONS; CERTIFICATE OF ANALYSIS. As of the time of such
          delivery by AHP, each batch of the Products will conform to the
          Specifications. AHP shall perform release testing in a manner
          consistent with testing methods agreed upon by the Parties. AHP shall
          provide to Horizon a Certificate of Analysis with each shipment of the
          Products to Horizon or its designated recipient stating that the
          Products conform to the Specifications and meet release
          specifications. The Certificate of Analysis shall be in a format
          agreed upon by the Parties and, if required under cGMP, such
          Certificate of Analysis shall include the Specifications and the
          results of release testing conducted by AHP on such Products. Upon
          Horizon's written request, AHP will also provide Horizon with a copy
          of the manufacturing and controls information for the applicable
          batch(es) delivered.

     2.7  LABELING. Within thirty (30) days after the Effective Date, Horizon,
          at its own expense, will provide AHP with Horizon's new labeling for
          the Product (including a new NDC number for each Product) bearing
          Horizon's corporate name and trade dress. If such labeling is changed
          in any manner other than a new NDC number and Horizon's corporate name
          and tradedress, such labeling shall be subject to the approval of AHP,
          which approval will not be unreasonably withheld. AHP agrees to either
          approve or disapprove such labeling within thirty (30) business days
          of AHP's receipt thereof from Horizon. AHP, at Horizon's expense, will
          print, either directly or through a Third Party, labels and other
          printed material to be included as part of the finished Product.
          Product manufactured by AHP after AHP's receipt and approval of
          Horizon's new labeling for the Product, shall bear such new labeling,
          provided, however, that AHP shall have no responsibility with respect
          to the content of such labeling, provided the content of the labeling
          printed by AHP is the same as the content of the labeling provided by
          Horizon. Horizon shall reimburse AHP for all reasonable costs incurred
          (on a Fully-Absorbed Cost basis) by AHP in making modifications to
          labeling, branding or imprinting, packaging and/or manufacturing
          processes to accommodate Horizon's new labeling or to accommodate any
          other changes requested by Horizon. Such reimbursement shall be made
          pursuant to invoices submitted by AHP to Horizon, which invoices shall
          be payable within thirty (30) days after Horizon's receipt thereof. In
          addition, should such new labeling result in any increase in AHP's
          cost of manufacturing the Product hereunder, the purchase price for
          such Product as calculated under Section 5.1 hereof, shall be
          increased by such additional costs. Notwithstanding the foregoing, AHP
          may supply Horizon with Product bearing AHP's labeling if such Product
          was manufactured and labeled prior to the Closing, it being agreed
          that Product manufactured from and after the Closing shall bear (i)
          AHP's label, or (ii) Horizon's new label.

     2.8  PURCHASE OF RESIDUAL INVENTORIES. Upon expiration or upon termination
          of this Agreement by AHP, upon AHP's request Horizon shall purchase
          from AHP (i) reasonable quantities of AHP's residual inventories of
          Products having not less than twelve months' remaining dating at the
          then current purchase price as determined in accordance with Section
          5.1 hereof, and (ii) reasonable quantities of AHP's residual
          inventories of Product specific Materials, including, without
          limitation, all labels and other Product specific packaging materials,
          but excluding all stocks of Substance and Materials used for the
          manufacture of Substance, at AHP's Fully Absorbed Cost for such
          Materials.

     2.9  INITIAL DELIVERY. AHP agrees to provide initial delivery of Products,
          subject to the timely receipt of an appropriate purchase order from
          Horizon in accordance with this Article 2, on or before Closing in
          accordance with procedures and terms to be set forth in the Systems
          Transfer documents developed by the Parties pursuant to Section 3.2 of
          the License Agreement.

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3.   MANUFACTURE OF PRODUCTS.

     3.1  MANUFACTURE OF PRODUCT. AHP agrees to manufacture and supply the
          Products in accordance with (i) the Specifications, (ii) the
          applicable Regulatory Approvals, as may be amended from time to time,
          and (iii) cGMP requirements, and all other applicable laws, rules and
          regulations. If

          (a)  upon Horizon's request the Parties mutually agree to change part
               or all of the Product manufacturing process, or

          (b)  any Product specific change in the applicable Regulatory
               Approvals (other than a change included under clause (a) above),
               applicable laws, rules or regulations requires a change in the
               Product manufacturing process

               Horizon shall reimburse AHP for all Fully Absorbed Costs incurred
               by AHP in connection with making such changes in the Product
               manufacturing process. Additionally, if either making any such
               change in the Product manufacturing process or any Product
               specific change in the applicable Regulatory Approvals,
               applicable laws, rules or regulations requires AHP to conduct
               development, testing or other activities (e.g., process
               development, stability testing, validation of new specifications,
               etc...) (collectively referred to as "Activities") in addition to
               those activities AHP conducted or is required to conduct in its
               manufacture of the Product immediately prior to such change in
               either the Product manufacturing process or the Product specific
               applicable Regulatory Approvals, applicable laws, rules or
               regulations being implemented, Horizon shall reimburse AHP for
               all Fully Absorbed Costs incurred by AHP in connection therewith.
               In addition to the foregoing, in the event that the Product
               manufacturing process is changed or AHP is required to conduct
               Activities in accordance with this Section 3.1, the purchase
               price for Product, other than for Product already manufactured
               and in inventory, shall be increased in an amount equivalent to
               the increase in AHP's manufacturing cost for Product, which
               increase shall be effective immediately upon AHP becoming aware
               of any proposed changes in the Regulatory Approvals, applicable
               laws, rules or regulations which requires either (i) a change in
               the Product manufacturing process or (ii) to AHP to conduct
               Activities, it will promptly notify Horizon and will consult with
               Horizon regarding the proposed changes and Activities, and will
               obtain Horizon's written consent prior to implementing the
               Activities and the changes, which consent shall not be
               unreasonably withheld. Notwithstanding the foregoing, in the
               event that Horizon requests changes in the manufacturing process,
               AHP shall not be obligated to make such change or conduct any
               Activities with respect thereto unless the parties mutually agree
               to make such change in the Product manufacturing process.

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     3.2  PROCUREMENT OF MATERIALS. AHP shall use its Commercially Reasonable
          Efforts to timely procure all Materials necessary for the production
          of the Products. Title to all such Materials shall reside in AHP.
          Notwithstanding the foregoing, AHP's obligation to supply Horizon with
          Product hereunder is subject to AHP's ability to obtain from Third
          Parties Materials in sufficient quantities to meet Horizon's and AHP's
          requirements for the manufacture of Products. AHP may, during any
          period of shortage of any Materials, prorate its supply of such
          Materials between Horizon and AHP's other uses (e.g., for sales of
          Products outside of the Territory or use in products other than
          Products) according to the relative quantities purchased/used by each
          during the immediately preceding twelve (12) months (or such shorter
          period of time that AHP has actually been supplying Product to Horizon
          hereunder if such shortage of Materials occurs prior to the first
          anniversary of the Effective Date) without regard to price. AHP shall
          use Commercially Reasonable Efforts to avoid entirely any such
          shortage or, if avoidance is not possible, to limit such period and
          amount and shall promptly inform Horizon if it becomes aware of any
          potential shortage. [***]

     3.3  REGULATORY FILINGS.  Horizon shall provide to AHP copies of all annual
          reports to the FDA.

     3.4  COMPLIANCE WITH LAWS AND REGULATIONS. While the Products are in its
          possession or under its control, AHP shall comply with all applicable
          federal, state and local statutory and regulatory requirements
          regarding the manufacture, packaging, handling and storage of the
          Products.

     3.5  PRODUCT COMPLAINTS. Horizon shall be solely responsible for
          interacting with the public with respect to complaints regarding
          Product quality. With respect to any such complaints, each Party shall
          have the responsibility for promptly conducting an investigation of
          any activities conducted by it under the Transaction Agreements which
          may be relevant to the complaint and each Party shall promptly report
          the results of such investigation to the other Party. The Parties
          shall cooperate in any investigation by the other Party of each such
          complaint which involves the Parties' duties under this Agreement.

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4.   TECHNOLOGY TRANSFER.

     4.1  TRANSFER OF PRODUCT MANUFACTURING KNOW-HOW. As soon as practicable
          after Horizon's request, and only if Horizon has complied with all of
          its obligations under the Transaction Agreements including, without
          limitation, the payment of all fees and payments that become due and
          payable prior to such time, AHP shall furnish Horizon with one copy of
          the Know-How, including all technical, manufacturing and AHP's other
          written information, including but not limited to process sheets, raw
          material and process specifications, manuals, vendors lists, and other
          writings specifically relating to the Products, which are currently
          used by AHP, its Affiliates or sub-contractors to manufacture or have
          manufactured Products according to the methods used by AHP or its
          Affiliates or subcontractors. AHP agrees that Horizon, its Affiliates
          or its permitted sublicensees, may use all Know-How listed in the
          preceding sentence for the manufacture of Products for sale in the
          Territory.

     4.2  TRAINING. In connection with the transfer of information described in
          Section 4.1, AHP shall permit a reasonable number of Horizon's
          technically skilled personnel and consultants designated by Horizon
          (with travel and living expenses paid by Horizon) to make one or more
          visits to such facilities of AHP or its Affiliates as may be engaged
          in the manufacture of Products for up to an aggregate of thirty (30)
          man-days in order to inspect and be instructed in all manufacturing
          techniques and procedures used by AHP, its Affiliates or
          subcontractors in the manufacture of Products.

     4.3  HORIZON'S USE OF KNOW-HOW. Horizon agrees that it shall use all
          Know-How provided to Horizon by or on behalf of AHP, its Affiliates or
          subcontractors pursuant to the Transaction Agreements for the sole
          purpose of making, using and/or selling the Products only in the
          Territory and shall not use or permit any Third Party to use such
          Know-How for the purpose of making Products for sale outside the
          Territory or for use as veterinary pharmaceutical products within or
          outside of the Territory. In the event, due to Horizon's failure to
          comply with any provision of the Transaction Agreements, such Know-How
          is used for the purpose of making Products for either sale outside the
          Territory or sale as veterinary pharmaceutical products within or
          outside of the Territory during such time period, Horizon shall
          immediately cease such use and/or sale and take such action as may be
          necessary to prevent a Third Party from using such Know-How for the
          purpose of making Products for sale outside the Territory and/or for
          sale as veterinary pharmaceutical products within or outside the
          Territory. The provisions of this Section shall not limit any other
          remedy AHP has on account of the use of such Know-How for the purpose
          of making Products for sale outside the Territory or for sale as
          veterinary pharmaceutical products within or outside the Territory.

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5.   PURCHASE PRICE.

     5.1  PRICE. Horizon shall purchase from AHP and AHP shall sell to Horizon
          Products at the purchase prices set forth in Schedule 5.1 hereof,
          which purchase prices shall be increased once each year by [***].

     5.2  FREIGHT, INSURANCE AND TAXES. Horizon shall pay all actual freight,
          insurance and government sales tax imposed on purchasers for resale,
          and duties and other fees (except tax on income to AHP) incurred in
          connection with the sale and shipment of the Products to Horizon.

     5.3  PAYMENT. Payments to AHP for the purchase price of delivered Products
          (as well as any other payment due from Horizon to AHP under this
          Agreement) shall be made by Horizon within thirty (30) days after the
          date of invoice, except as to Product orders which are rejected by
          Horizon in accordance with the procedures recited in Article 6, or
          which the Parties dispute are in conformance with the Specifications.
          In the event Product is rejected by Horizon, but is determined to be
          Acceptable Product pursuant to Section 6.2 hereof, the payment for
          such Product shall be due and payable within ten (10) days after the
          determination with respect to such Product is made in accordance with
          Section 6.2 hereof.

     5.4  MAINTENANCE OF RECORDS; AUDITS. AHP shall keep complete records of
          AHP's Fully Absorbed Costs for the manufacture and supply of Products
          hereunder, and shall permit an independent certified public accountant
          selected by Horizon and reasonably acceptable to AHP, at Horizon's
          expense, at the time of (a) any price adjustment under Section 5.1, or
          (b) request by AHP for reimbursement of costs incurred under Sections
          2.7 and 3.1 hereof, but, in any event, no more than once per year, to
          inspect and review such records during normal business hours and upon
          reasonable prior notice, in order to verify or determine such costs
          and whether an increase in such costs has occurred. The independent
          certified public accountant may not disclose to Horizon specific
          manufacturing cost breakdowns, but only whether or not the increase in
          AHP's Fully Absorbed Cost reported by AHP are correct. Horizon shall
          bear the costs and fees associated with such inspections and reviews
          unless it is determined by the independent certified public accountant
          that such price adjustment was unjustified (in excess of five percent
          (5%) more than the price increase determined by the independent
          certified public accountant to be justified), in which case AHP shall
          bear the costs and fees of such audit and shall promptly refund to
          Horizon any overpayments made by Horizon because of such unjustified
          price adjustment.

<PAGE>   13
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


6.   INSPECTION OF PRODUCT.

     6.1  INSPECTION; REJECTION OF PRODUCT. Horizon shall analyze representative
          samples of each lot of Product delivered to Horizon for purposes of
          determining whether the same meets the Specifications and was
          manufactured in accordance with the NDA and cGMP ("Acceptable
          Product") and, if performed, will do so within thirty (30) days from
          the date of delivery of such Products to Horizon's carrier. Horizon
          shall notify AHP in writing within said thirty (30) days of any of the
          Product or portion thereof, which Horizon is rejecting because it is
          not Acceptable Product. If Horizon fails to notify AHP that it is
          rejecting a lot of Product within such thirty (30) day period, such
          lot of Product shall be deemed to be Acceptable Product. In the event
          of a recall of Product, Section 9.1 hereof shall govern.

     6.2  THIRD PARTY ANALYSIS. If AHP, after good faith consultation with
          Horizon, disputes any finding by Horizon that Product is not
          Acceptable Product, representative samples of such Product shall be
          forwarded to a Third Party jointly selected by AHP and Horizon, in
          their reasonable discretion, for analysis, which analysis shall be
          performed in compliance with applicable FDA regulations for retesting
          of pharmaceutical products. The findings of such Third Party regarding
          whether the Product was Acceptable Product shall be binding upon the
          Parties. The cost of such analysis by such Third Party shall be borne
          by the Party whose findings differed from those generated by such
          Third Party.

     6.3  REPLACEMENT OF PRODUCT. AHP shall replace any Product order, or
          portion thereof, which is not Acceptable Product (unless such
          non-conformance is due to any negligent or wrongful act or omission by
          Horizon or its agents or subcontractors), at its cost and expense,
          including shipping costs.

     6.4  DISPOSITION OF REJECTED PRODUCT. AHP shall instruct Horizon as to the
          disposition of any Product order or portion thereof determined not to
          be Acceptable Product. At the sole option of AHP, said Product may be
          returned to AHP, at AHP's expense including shipping costs, or
          destroyed in an environmentally acceptable manner, at AHP's expense.
<PAGE>   14
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


7. INSPECTION AND ACCESS TO FACILITY AND RECORDS.

     7.1  INSPECTION BY REGULATORY AUTHORITIES. Upon the request of the FDA or
          other regulatory agency, such agency shall have access to observe and
          inspect AHP's or its Affiliates' facilities and procedures used for
          the manufacture, testing or warehousing of the Products and to audit
          such facilities for compliance with cGMP and/or other applicable
          regulatory standards.

     7.2  NOTIFICATION OF INQUIRIES AND INSPECTIONS. AHP also agrees to notify
          Horizon within ten (10) business days or such shorter time as may be
          required by the notification of the inspection, of any written or oral
          inquiries, notifications or inspection activity by the FDA or other
          regulatory agency in regard to any Product. AHP shall permit not more
          than two (2) Horizon representatives to attend any such inspections,
          and shall provide a reasonable description of any such governmental
          inquiries, notifications or inspections promptly after such visit or
          inquiry. AHP shall furnish to Horizon (i) within ten (10) business
          days after receipt, any report or correspondence issued by the FDA or
          other governmental agency in connection with such visit or inquiry,
          including but not limited to, any FDA Form 483 (List of Inspectional
          Observations) or applicable portions of any FDA Warning Letters which
          pertain to the Products in the Territory and (ii) not later than ten
          (10) business days prior to the time it provides to the FDA or other
          regulatory agency, copies of proposed responses or explanations
          relating to items set forth above (each, a "Proposed Response"), in
          each case redacted of trade secrets or other confidential or
          proprietary information of AHP that are unrelated to the obligations
          under this Agreement or are unrelated to the Products. AHP shall
          discuss with Horizon and consider in good faith any comments provided
          by Horizon on the Proposed Response. After the filing of a response
          with the FDA or other regulatory agency, AHP will notify Horizon of
          any further contacts with such agency relating to the subject matter
          of the response.

     7.3  INSPECTION BY HORIZON. AHP shall permit Horizon to inspect once
          annually that portion of the AHP facility where Product is
          manufactured and review such Product documents as is reasonably
          necessary for the purpose of assessing AHP's compliance with
          applicable regulations. Such inspection and document review shall be
          conducted upon reasonable prior notice by Horizon, but not less than
          thirty (30) days prior to the proposed inspection, at a time and date
          mutually agreeable to the Parties. In addition, in the event Horizon
          has received two or more shipments of Product determined not to be
          Acceptable Product pursuant to the procedures of Article VI hereof
          within a single Calendar Quarter, Horizon shall be permitted to
          conduct an additional such inspection to help determine the reason(s)
          for delivery of such non-Accepted Product.
<PAGE>   15
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


8.   WARRANTIES AND INDEMNITIES.

     8.1  REPRESENTATIONS AND WARRANTIES OF EACH PARTY. As of the Effective
          Date, each of Horizon and AHP hereby represents, warrants and
          covenants to the other Party hereto a follows:

          (a)  it is a corporation or entity duly organized and validly existing
               under the laws of the state or other jurisdiction of
               incorporation or formation;

          (b)  the execution, delivery and performance of this Agreement by such
               Party has been duly authorized by all requisite corporate action
               and do not require any shareholder action or approval;

          (c)  it has the power and authority to execute and deliver this
               Agreement and to perform its obligations hereunder;

          (d)  the execution, delivery and performance by such Party of this
               Agreement and its compliance with the terms and provisions hereof
               does not and will not conflict with or result in a breach of any
               of the terms and provisions of or constitute a default under (i)
               a loan agreement, guaranty, financing agreement, agreement
               affecting a product or other agreement or instrument binding or
               affecting it or its property; (ii) the provisions of its charter
               or operative documents or bylaws; or (iii) any order, writ,
               injunction or decree of any court or governmental authority
               entered against it or by which any of its property is bound; and

          (e)  it shall at all times comply with all applicable material laws
               and regulations relating to its activities under this Agreement.

     8.2  REPRESENTATIONS AND WARRANTIES OF AHP. In addition to the
          representations and warranties made by AHP in Section 8.1 hereof, AHP
          hereby represents and warrants to Horizon as follows:

          (a)  that all Products supplied hereunder conform to the
               Specifications, will be (and with respect to the initial delivery
               of Product to Horizon hereunder, were) manufactured in accordance
               with the applicable Regulatory Approvals and cGMP, and, subject
               to Section 2.7 hereof, will not be (and, with respect to the
               initial delivery of Product to Horizon hereunder, were not)
               adulterated or misbranded while in AHP's possession; and

          (b)  that it has not and will not use in any capacity the services of
               any persons debarred under 21 U.S.C. ss.335(a) or 335(b) in
               connection with the manufacture of the Products.

     8.3  COVENANTS OF HORIZON. In addition to the representations and
          warranties made by Horizon in Section 8.1 hereof and the covenants
          made by Horizon elsewhere in this Agreement, Horizon hereby covenants
          to AHP that it shall not sell the Products manufactured by AHP
          hereunder in countries other than those within the Territory and that
          it shall not sell such Products for veterinary use within or outside
          the Territory. Horizon further covenants that it shall not sell such
          Products to any Third Party which Horizon has reason to believe might
          sell the Products in countries other than those within the Territory.
          In the case of any such Third Party sales, Horizon shall exercise its
          Commercially Reasonable Efforts, consistent with applicable law, to
          gain a cessation of such Third Party sales of Products within such
          countries, including, to the extent possible, terminating its sales of
          Product to such Third Party.
<PAGE>   16
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


     8.4  NO OTHER WARRANTIES. EXCEPT FOR THE WARRANTIES EXPRESSLY MADE BY AHP
          IN SECTIONS 8.1 AND 8.2 HEREOF, AHP MAKES NO OTHER REPRESENTATION OR
          WARRANTIES, EITHER EXPRESS OR IMPLIED (WHETHER WRITTEN OR ORAL),
          INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR ANY
          WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE
          PRODUCTS OR AHP'S OBLIGATIONS HEREUNDER. ADDITIONALLY, EXCEPT FOR THE
          WARRANTIES MADE BY HORIZON IN THIS AGREEMENT, HORIZON MAKES NO OTHER
          REPRESENTATION OR WARRANTY, EITHER EXPRESS OR IMPLIED (WHETHER WRITTEN
          OR ORAL) WITH RESPECT TO HORIZON'S OBLIGATIONS HEREUNDER.

     8.5  INDEMNIFICATION BY AHP. AHP shall indemnify, defend and hold harmless
          Horizon, its Affiliates and their respective officers, directors,
          shareholders, employees, agents and representatives (each a "Horizon
          Indemnified Party") from any claims, losses, liabilities, costs,
          expenses (including reasonable attorney's fees) and damages to Third
          Parties, including any related to property or personal injury (each a
          "Liability") which the Horizon Indemnified Party may incur, suffer or
          be required to pay resulting from or arising in connection with (a)
          the breach by AHP of any representation or warranty contained in this
          Agreement; (b) any violation by AHP of any applicable federal, state
          or local regulation, statute or order in the manufacture and packaging
          of Products arising out of AHP's duties under this Agreement which is
          not attributable to printed materials provided by Horizon; or (c) any
          negligent act or omission by AHP or its affiliates in carrying out its
          obligations under this Agreement. Notwithstanding the foregoing, AHP
          shall have no obligations to defend, indemnify or hold harmless any
          Horizon Indemnified Party for any Liability that results from the
          negligence or intentional misconduct of Horizon, its Affiliates, or
          any of its permitted sublicensees or any of their respective officers,
          directors, employees, agents, consultants or representatives.

     8.6  INDEMNIFICATION BY HORIZON. Horizon shall indemnify, defend and hold
          harmless AHP and its Affiliates, and each of its and their respective
          employees, officers, directors and agents (each, an "AHP Indemnified
          Party") from and against any Liability which the AHP Indemnified Party
          may incur, suffer or be required to pay resulting from or arising in
          connection with (a) the breach by Horizon of any representation or
          warranty contained in this Agreement; (b) materials or promotional
          claims (except to the extent that AHP has previously reviewed and
          approved the specific material or promotional claim under Section 8.2
          of the License Agreement), (c) the manufacture, packaging, promotion,
          distribution, testing, use, marketing, sale or other disposition of
          Products by Horizon, its Affiliates, its permitted sublicensees or
          their respective subcontractors; or (d) the use of the Trademark by
          Horizon, its Affiliates, its permitted sublicensees or their
          respective subcontractors. Notwithstanding the foregoing, Horizon
          shall have no obligations to indemnify, defend, or hold harmless any
          AHP Indemnified Party for any Liability that results from the
          international misconduct or negligence of AHP, its Affiliates, its
          permitted sublicensees or any of their respective employees, officers,
          directors or agents, consultants or representatives.
<PAGE>   17
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


     8.7  CONDITIONS TO INDEMNIFICATION. The obligations of the indemnifying
          Party under Sections 8.5 and 8.6 are conditioned upon the delivery of
          written notice to the indemnifying Party of any potential Liability
          promptly after the indemnified Party becomes aware of such potential
          Liability. The indemnifying Party shall have the right to assume the
          defense of any suit or claim relating to the Liability if it has
          assumed responsibility for the suit or claim in writing; however, if
          in the reasonable judgment of the indemnified Party, such suit or
          claim involves an issue or matter which could have a materially
          adverse effect on the business operations or assets of the indemnified
          Party, the indemnified Party may waive its rights to indemnity under
          this Agreement and control the defense or settlement thereof, but in
          no event shall any such waiver be construed as a waiver of any
          indemnification rights such Party may have at law or in equity. If the
          indemnifying Party defends the suit or claim, the indemnified Party
          may participate in (but not control) the defense thereof at its sole
          cost and expense.

     8.8  SETTLEMENTS. Neither Party may settle a claim or action related to a
          Liability without the consent of the other Party, if such settlement
          would impose any monetary obligation on the other Party or require the
          other Party to submit to an injunction or otherwise limit the other
          Party's rights under this Agreement. Except as otherwise expressly set
          forth in this Article 8, any payment made by a Party to settle any
          such claim or action shall be at its own cost and expense.

     8.9  LIMITATION OF LIABILITY. With respect to any claim by one Party
          against the other arising out of the performance or failure of
          performance of the other Party under this Agreement, the Parties
          expressly agree that the liability of such Party to the other Party
          for such breach shall be limited under this Agreement or otherwise at
          law or equity to direct damages only and in no event shall a Party be
          liable for, punitive, exemplary or consequential damages. The
          limitations set forth in this Section 8.9 shall not apply with respect
          to the obligations of either Party to indemnify the other under
          Sections 8.5 or 8.6 hereof in connection with a Liability to a third
          party.

     8.10 INSURANCE. Horizon shall obtain and maintain at all times during the
          term of this Agreement Commercial General Liability Insurance,
          including Products Liability, with limits of liability of not less
          than [***] Dollars ($[***]) per occurrence and [***] Dollars ($[***])
          in the aggregate. Horizon shall provide AHP with a Certificate of
          Insurance evidencing this coverage within thirty (30) days of the
          Effective Date. Such insurance policy shall name AHP as an additional
          insured and Horizon shall use its Commercially Reasonable Efforts to
          ensure such insurance policy contains a provision requiring ten (10)
          day advance notification to AHP in the event of its cancellation or
          termination. AHP shall maintain self insurance and/or insurance
          obtained from Third Party insurers in amounts sufficient to cover its
          obligations under Section 8.5. Upon Horizon's written request, AHP
          shall provide Horizon with evidence of such insurance coverage.


<PAGE>   18

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

9.   RECALLS.

     9.1  PRODUCT RECALLS. In the event of an actual or threatened recall of any
          Product required or recommended by a governmental agency or authority
          of competent jurisdiction within the Territory or if recall of any
          Product is (i) reasonably deemed advisable by AHP or by Horizon, or
          (ii) jointly deemed advisable by AHP and Horizon, such recall shall be
          promptly implemented and administered by Horizon in a manner which is
          appropriate and reasonable under the circumstances and in conformity
          with accepted trade practices. In the event that a recall is caused
          because, due to negligent acts or omissions of AHP, its Affiliates or
          subcontractors, Product supplied by AHP to Horizon does not conform to
          the Specifications or was not manufactured in accordance with the
          applicable Regulatory Approvals and cGMP, the cost, including
          Horizon's reasonable out-of-pocket expenses, of any such recall shall
          be borne by AHP. Horizon shall pay all costs, including AHP's
          reasonable out-of-pocket expenses, associated with a recall for any
          other reason, including without limitation, recalls (i) caused by
          actions of Third Parties occurring after such Product is sold by
          Horizon, (ii) due to packaging or label defects for which Horizon has
          responsibility or (iii) due to any other breach by Horizon of its
          duties under this Agreement.

     9.2  NOTICE OF EVENTS THAT MAY LEAD TO PRODUCT RECALL. Each Party shall
          keep the other fully and promptly informed of any notification, event
          or other information, whether received directly or indirectly, which
          might affect the marketability, safety or effectiveness of Products or
          might result in a recall of Products by the FDA.

     9.3  RECALL DUE TO BREACH BY AHP. In the event of any recall for which AHP
          would be responsible for the costs in accordance with Section 9.1
          hereof, AHP shall, at the election of Horizon either:

          (a)  supply Products, without chare to Horizon, in an amount
               sufficient to replace the amounts of Products recalled, or

          (b)  refund to Horizon or give credit to Horizon against outstanding
               receivables due from Horizon for the price of Products to be
               delivered to Horizon in the future, in amounts equal to the price
               paid by Horizon to AHP for Products so recalled plus the
               reasonable transportation costs incurred by Horizon and not
               recovered by Horizon in respect of such recalled Products.

               In addition, if, as a direct result of any recall for which AHP
               would be responsible for the costs in accordance with Section 9.1
               hereof, Horizon's aggregate sales of Products in any consecutive
               thirty (30) day period fall below fifty percent (50%) of
               Horizon's average monthly sales of Products for the preceding six
               (6) months, then Horizon may postpone payment of the first and
               second payments following the recall otherwise due and payable
               under Section 4.1(ii) of the License agreement for six (6)
               months, after which Horizon shall resume making such payments,
               including immediate payment of the two postponed payments.

     9.4  DEFINITION OF RECALL. For Purposes of this Article 9, "recall" shall
          mean any action by Horizon and its Affiliates, or AHP and its
          Affiliates, to recover title or possession or halt distribution,
          prescription or consumption of Products sold or shipped to Third
          Parties. The term "recall" also applies to Product which would have
          been subject to recall if it had been sold or shipped.


<PAGE>   19
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

     9.5  SURVIVAL OF OBLIGATIONS. The provisions and obligations of this
          Article 9 shall survive any termination of this Agreement.

10.  TERM AND TERMINATION.

     10.1 TERM. This Agreement shall become effective upon the Effective Date of
          the License Agreement and, unless earlier terminated as provided
          below, shall remain in full force and effect for a period ending on
          the second (2nd) anniversary of the Effective Date (the "Term").
          Thereafter, the term of this Agreement may be extended by Horizon on
          six (6) months' prior written notice for up to six (6) additional
          months provided that the Parties agree upon all terms and conditions
          of such extension not later than the expiration of the Term. The
          Supply Price would be negotiated but shall not be less than AHP's
          Fully Absorbed Cost plus a [***] mark-up. If the Parties have not
          extended the term of this Agreement or signed a new supply agreement
          before the expiration of the Term, AHP shall have no obligation to
          supply Horizon with any Product after expiration of the Term. Upon
          expiration or termination of this Agreement for any reason, all unpaid
          amounts due pursuant to Section 5.1 shall become immediately due and
          payable.

     10.2 TERMINATION BY AHP. AHP may terminate this Agreement, except as
          limited hereinafter, immediately upon written notice, in the event

          (a)  Horizon fails to make any payment due and owing within thirty
               (30) days after notice thereof from AHP that such payment has not
               been made by Horizon by the date specified in Section 5.3; or

          (b)  Horizon commits a breach of any material provision of this
               Agreement which breach remains uncured for sixty (60) days,
               measured from the date written notice of such breach is given to
               Horizon, or if such breach is not susceptible of cure within such
               sixty (60) day period and Horizon uses good faith efforts to cure
               such breach, for one hundred eighty (180) days after written
               notice to Horizon; or

          (c)  the License Agreement is terminated for any reason, other than
               AHP's breach of the License Agreement, prior to the expiration of
               the Term of this Agreement.


<PAGE>   20

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

     10.3 TERMINATION BY HORIZON. Horizon may terminate this Agreement, in whole
          or with regard to a specific Product as applicable, immediately upon
          written notice in the event (a) AHP commits a breach of any material
          provision of this Agreement, which is not cured within thirty (30)
          days in case of a failure to make any payment due and owing; or (b)
          AHP commits a breach of any material provision of this Agreement which
          breach remains uncured for sixty (60) days, measured from the date
          written notice of such breach is given to AHP, or if such breach is
          not susceptible of cure within such sixty (60) day period and AHP uses
          good faith efforts to cure such breach, for one hundred eighty (180)
          days after written notice to AHP; or (c) the License Agreement is
          terminated for any reason other than Horizon's breach of the License
          Agreement prior to the expiration of the Term of this Agreement.

     10.4 INSOLVENCY. Either party may terminate this Agreement upon the filing
          or institution of bankruptcy, reorganization, liquidation or
          receivership proceedings, or upon an assignment of a substantial
          portion of the assets for the benefit of creditors by the other Party,
          or in the event a receiver or custodian is appointed for such party's
          business, or if a substantial portion of such Party's business is
          subject to attachment or similar process; provided, however, that in
          the case of any involuntary bankruptcy proceeding such right to
          terminate shall only become effective if the proceeding is not
          dismissed within ninety (90) days after the filing thereof.

     10.5 EFFECT OF TERMINATION. Upon termination or expiration of this
          Agreement, except in the event of termination of the Agreement by AHP
          pursuant to Sections 10.2 or 10.4, AHP shall have the obligations set
          forth in Sections 4.1 and 4.2. If AHP terminates this Agreement
          pursuant to either Section 10.2 or 10.4, the obligations set forth in
          Sections 4.1 and 4.2 hereof shall survive termination if Horizon has
          made or accelerates payment of all payments to AHP required under
          Section 4.1 of the License Agreement, and otherwise the obligations
          under Sections 4.1 and 4.2 hereof shall not survive termination. In
          the event that Horizon terminates this Agreement pursuant to Section
          10.3 hereof because of a failure to supply Product to Horizon which
          failure to supply results in an uncured breach of this Agreement by
          AHP, Horizon shall thereafter be permitted to manufacture Product
          either directly or through a Third Party and the transfer of
          manufacturing Know-How under Section 4.1 shall be accomplished as soon
          as practicable, but in no event more than thirty (30) days, after this
          Agreement is so terminated and the reasonable out-of-pocket costs
          incurred by the Parties in transferring such Product manufacturing
          responsibilities from AHP to either Horizon, its Affiliates or a Third
          Party shall be borne by AHP.

     10.6 ACCRUED OBLIGATIONS. Termination of this Agreement for any cause shall
          not release either Party from any obligation theretofore accrued.

     10.7 NO WAIVER. The failure on the part of either Party to exercise or
          enforce any right conferred upon it hereunder shall not be deemed to
          be a waiver of any such right nor operate to bar the exercise or
          enforcement thereof at any time thereafter.
<PAGE>   21

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

    10.8  OUTSTANDING ORDERS. Upon termination of this Agreement for any reason
          other than pursuant to Sections 10.2 or 10.5 hereof, AHP shall fill
          all outstanding purchase orders of Horizon or its Affiliates for the
          Products, unless otherwise instructed by Horizon.

    10.9  BULK SUBSTANCE. To the extent permitted under the supply agreement
          planned to be entered into between AHP and its supplier of Substance
          (the "Bulk Substance Supply Agreement"), AHP will use commercially
          reasonable efforts to have such supplier enter into a direct supply
          agreement for Substance with Horizon upon expiration of this
          Agreement, on the same terms and conditions, including price, as the
          Bulk Substance Supply Agreement. AHP shall not be required, as part of
          its commercially reasonable efforts, to pay any money or provide any
          other form of consideration to such supplier. Upon expiration of this
          Agreement, if such direct supply agreement is not entered into, AHP
          and Horizon will cooperate in a mutually agreeable arrangement under
          which to the extent feasible Horizon would obtain the benefits and
          assume the obligations of AHP under the Bulk Substance Supply
          Agreement as it relates to Substance, including subcontracting to
          Horizon, or under which AHP would enforce for the benefit of Horizon,
          with Horizon assuming AHP's obligations, any and all rights of AHP
          against such supplier. The purpose of such an arrangement would be for
          Horizon to obtain price, quantity, destination and delivery date terms
          comparable to AHP's rights under the Bulk Substance Supply Agreement.

    10.10 SURVIVAL. Subject to Section 10.5 hereof, the following provisions
          shall survive expiration or termination of this Agreement: Sections
          2.8, 3.3, 4.1, 4.2, 4.3, 5.4, 10.9, 10.10, 12.6 and 12.7 and Articles
          8, 9 and 11.

11.  CONFIDENTIALITY.

    11.1  NONDISCLOSURE OBLIGATION. Each of Horizon and AHP shall use only in
          accordance with this Agreement and shall not disclose to any Third
          Party any information including, without limitation, Know-How,
          received by it from the other Party (the "Information"), without the
          prior written consent of the other Party. The foregoing obligations
          shall survive the expiration or earlier termination of the last of the
          Transaction Agreements to so expire or to be so terminated for a
          period of five (5) years. These obligations shall not apply to
          Information that:

          (i)   is known by the receiving Party at the time of its receipt, and
                not through a prior disclosure by the disclosing Party, as
                documented by business records;

          (ii)  is at the time of disclosure or thereafter becomes published or
                otherwise part of the public domain without breach of this
                Agreement by the receiving Party;

          (iii) is subsequently disclosed to the receiving Party by a Third
                Party who has the right to make such disclosure;

          (iv)  is developed by the receiving Party independently of the
                Information received from the disclosing Party and such
                independent development can be documented by the receiving
                Party; or

          (v)   is required by law, regulation, rule, act or order of any
                governmental authority or agency to be disclosed by a Party,
                provided that notice is promptly delivered to the other Party in
                order to provide an opportunity to seek a protective order or
                other similar order with respect to such Information and
                thereafter the disclosing Party discloses to the requesting
                entity only the minimum Information required to be disclosed in
                order to comply with the request, whether or not a protective
                order or other similar order is obtained by the other Party.
<PAGE>   22

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

     11.2 PERMITTED DISCLOSURES. Information may be disclosed to employees,
          agents, consultants, sublicensees or suppliers of the recipient Party
          or its Affiliates, but only to the extent required to accomplish the
          purposes of this Agreement and only if the recipient Party obtains
          prior agreement from its employees, agents, consultants, sublicensees,
          suppliers or Third Party manufacturers to whom disclosure is to be
          made to hold in confidence and not make use of such Information for
          any purpose other than those permitted by this Agreement. Each Party
          will use at least the same standard of care as it uses to protect
          proprietary or confidential information of its own to ensure that such
          employees, agents, consultants, sublicensees, suppliers or Third Party
          manufacturers do not disclose or make any unauthorized use of the
          Information.

     11.3 DISCLOSURE OF AGREEMENT. Neither Horizon nor AHP shall release to any
          Third Party or publish in any way any non-public information with
          respect to the terms of this Agreement or concerning their cooperation
          without the prior written consent of the other, which consent will not
          be unreasonably withheld or delayed, provided, however, that either
          Party may disclose the terms of this Agreement to the extent required
          to comply with applicable laws, including, without limitation, the
          rules and regulations promulgated by the United States Securities and
          Exchange Commission, provided, however, that prior to making any such
          disclosure, the Party intending to so disclose the terms of this
          Agreement shall (i) provide the nondisclosing Party with written
          notice of the proposed disclosure and an opportunity to review and
          comment on the intended disclosure which is reasonable under the
          circumstances and (ii) shall seek confidential treatment for as much
          of the disclosure as is reasonable under the circumstances, including,
          without limitation, seeking confidential treatment of any information
          as may be requested by the other Party. Notwithstanding any other
          provision of this Agreement, each Party may disclose the terms of this
          Agreement to lenders, investment bankers and other financial
          institutions of its choice solely for purposes of financing the
          business operations of such Party either (i) upon the written consent
          of the other Party or (ii) if the disclosing Party uses reasonable
          efforts to obtain a signed confidentiality agreement with such
          financial institution with respect to such information on terms
          substantially similar to those contained in this Article 11.

     11.4 PUBLICITY. Subject to Section 11.3, all publicity, press releases and
          other announcements relating to this Agreement or the transactions
          contemplated hereby shall be reviewed in advance by, and shall be
          subject to the approval of, both Parties. The Party responding to a
          request for such approval shall respond to the other Party in writing
          within five (5) days of such request.

     11.5 WAIVER. AHP agrees that, upon AHP and its supplier of Substance
          entering into the Bulk Substance Supply Agreement, AHP shall waive its
          rights under the Confidentiality Agreement among AHP, Horizon, EJ
          Financial and Mikart, the License Agreement and this Agreement to the
          extent such agreements prohibit Horizon from communicating with such
          supplier and entering into agreement(s) regarding the Substance with
          such supplier.

12.  MISCELLANEOUS.

     12.1 FORCE MAJEURE. Neither Party shall be liable to the other for delay or
          failure in the performance of the obligations on its part contained in
          this Agreement if and to the extent that such failure or delay is due
          to circumstances beyond its control (including, without limitation,
          AHP's inability to obtain, from a Third Party, sufficient quantities
          of the raw materials needed for the manufacture of Substance to meet
          its manufacturing obligations hereunder) which it could not have
          avoided by the exercise of reasonable diligence. It shall notify the
          other Party promptly should such circumstances arise, giving an
          indication of the likely extent and duration thereof, and shall use
          all Commercially Reasonable Efforts to resume performance of its
          obligations as soon as practicable.

<PAGE>   23

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

     12.2 ASSIGNMENT.

          12.2.1 ASSIGNMENT BY HORIZON. Horizon may assign any or all of its
               right or obligations under this Agreement in the Territory to any
               of its Affiliates, for so long as they remain Affiliates. In
               addition, Horizon may assign any or all of its rights or
               obligations under this Agreement in the Territory in conjunction
               with a merger or acquisition of Horizon. Horizon may not
               otherwise assign any of its rights or obligations under this
               Agreement without AHP's prior written consent, which consent
               shall not be unreasonably withheld. AHP shall respond to such
               requests by Horizon for assignment within thirty (30) days from
               such request. Any permitted assignment shall not relieve Horizon
               of its responsibilities for performance of its obligations under
               this Agreement.

          12.2.2 ASSIGNMENT BY AHP. AHP may assign any or all of its rights or
               obligations under this Agreement to any of its Affiliates or to
               any Third Party, provided, however, that AHP may assign all or
               part of its obligations to a Third Party only after receiving
               Horizon's prior written consent, which consent shall not be
               unreasonably withheld or delayed; provided, further, that such
               assignment shall not relieve AHP of its responsibilities for
               performance of its obligations under this Agreement.
               Notwithstanding the foregoing, Horizon's consent shall not be
               required for any assignment made by AHP in connection with a
               merger or similar reorganization of AHP or its parent company or
               the sale of all or substantially all of AHP's or AHP's parent
               company's pharmaceutical assets.

          12.2.3 BINDING NATURE OF ASSIGNMENT. This Agreement shall be binding
               upon and inure to the benefit of the successors and permitted
               assigns of the Parties. Any assignment not in accordance with
               this Section 12.2 shall be void.

     12.3 NO WAIVER. The failure of either Party to require performance by the
          other Party of any of that other Party's obligations hereunder shall
          in no manner affect the right of such Party to enforce the same at a
          later time. No waiver by any Party hereto of any condition, or of the
          breach of any provision, term, representation or warranty contained in
          this Agreement, whether by conduct or otherwise, in any one or more
          instances, shall be deemed to be or construed as a further or
          continuing waiver of any such condition or breach, or of any other
          condition or of the breach of any other provision, term,
          representation or warranty hereof.

     12.4 SEVERABILITY. If a court or other tribunal of competent jurisdiction
          should hold any term or provision of this Agreement to be excessive,
          or invalid, void or unenforceable, the offending term or provision
          shall be deleted or revised to the extent necessary to be enforceable,
          and, if possible, replaced by a term or provision which, so far as
          practicable, achieves the legitimate aims of the Parties.

     12.5 RELATIONSHIP BETWEEN THE PARTIES. Both Parties are independent
          contractors under this Agreement. Nothing herein contained shall be
          deemed to create an employment, agency, joint venture or partnership
          relationship between the Parties hereto or any of their agents or
          employees, or any other legal arrangement that would impose liability
          upon one party for the act or failure to act of the other Party.
          Neither Party shall have any express or implied power to enter into
          any contracts or commitments or to incur any liabilities in the name
          of, or on behalf of, the other Party, or to bind the other Party in
          any respect whatsoever.

<PAGE>   24

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

     12.6 CORRESPONDENCE AND NOTICES.

          12.6.1 ORDINARY NOTICES. Correspondence, reports, documentation, and
               any other communication in writing between the Parties in the
               course of ordinary implementation of this Agreement shall be
               delivered by hand, sent by facsimile, overnight courier or by
               airmail to the employee or representative of the other Party who
               is designated by such other Party to receive such written
               communication.

          12.6.2 EXTRAORDINARY NOTICES. Extraordinary notices and communications
               (including, without limitation, notices of termination, force
               majeure, material breach, change of address) shall be in writing
               and sent by prepaid registered or certified air mail, or by
               facsimile confirmed by prepaid registered or certified air mail
               letter, and shall be deemed to have been properly served to the
               addressee upon receipt of such written communication.

          12.6.3 ADDRESSES. In the case of Horizon, the proper address for
               communications and for all payments shall be:

                       Horizon Pharmaceutical Corporation
                        660 Hembree Parkway, Suite 106
                        Roswell, Georgia 30076
                        Attn: Mr. Brent Dixon
                        Fax: (770) 442-9594

               and in the case of AHP, the proper address for communications and
               for all payments shall be:

                       Wyeth-Ayerst Laboratories
                       555 Lancaster Avenue
                       St. Davids, Pennsylvania  19087
                       Attn: Senior Vice President, Global Business Development
                       Fax: (610) 688-9498

               with a copy to:

                       American Home Products Corporation
                       5 Giralda Farms
                       Madison, New Jersey  07940
                       Attn: Senior Vice President and General Counsel
                       Fax: (973) 660-7156

<PAGE>   25

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

    12.7  CHOICE OF LAW. This Agreement is subject to and governed by the laws
          of the State of Delaware, excluding its conflict of law provisions.

    12.8  ENTIRE AGREEMENT; AMENDMENT. This Agreement, together with the other
          Transaction Agreements and the Confidential Disclosure Agreement
          between AHP and E.J. Financial Enterprises Inc. (an equity holder in
          Horizon) dated April 28, 1998, and all the covenants, promises,
          agreements, warranties, representations, conditions and understandings
          contained herein and therein sets forth the complete, final and
          exclusive agreement between the Parties and supersedes and terminates
          all prior and contemporaneous agreements and understandings between
          the Parties, whether oral or in writing. There are no covenants,
          promises, agreements, warranties, representations, conditions or
          understandings, either oral or written, between the Parties other than
          as are set forth in the Transaction Agreements. No subsequent
          alteration, amendment, change, waiver or addition to this Agreement
          shall be binding upon the Parties unless reduced to writing and signed
          by an authorized officer of each Party. No understanding, agreement,
          representation or promise, not explicitly set forth herein, has been
          relied on by either Party in deciding to execute this Agreement.

    12.9  HEADINGS. The headings and captions used in this Agreement are solely
          for the convenience of reference and shall not affect its
          interpretation.

    12.10 COUNTERPARTS. This Agreement may be executed in one or more
          counterparts each of which shall be an original and all of which shall
          constitute together the same document.

    12.11 FURTHER ACTIONS. Each Party agrees to execute, acknowledge and deliver
          such further instruments, and to do all other acts, as may be
          necessary or appropriate in order to carry out the purposes and intent
          of this Agreement including, without limitation, any filings with any
          antitrust agency which may be required.

     IN WITNESS WHEREOF, this Agreement has been executed by the duly authorized
representatives of the Parties as of the date set forth below.


AMERICAN HOME PRODUCTS CORPORATION        HORIZON PHARMACEUTICAL CORPORATION


By:___________________________________    By:___________________________________

Name:_________________________________    Name:_________________________________

Title:________________________________    Title:________________________________




<PAGE>   26

                                  SCHEDULE 1.19

                                 SPECIFICATIONS



         PRODUCT SPECIFICATIONS ARE SET FORTH ON THE FOLLOWING 22 PAGES



<PAGE>   27
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION



<TABLE>
<S>                                                  <C>
LABEL CLAIM:                                         [***]

DOSAGE FORM:                                         [***]

LOT SIZE:                                            [***]

PACKAGE SIZE:                                        [***]

PRODUCT CODE:                                        [***]

NDA NO.:                                             [***]

RX OR OTC:                                           [***]

OFFICIAL NF OR USP:                                  [***]

DEA CLASS:                                           [***]

FORM 6 NO.:                                          [***]

EXPIRATION DATE:                                     [***]

MFD. BY:                                             [***]
</TABLE>

              TABLE OF CONTENTS

PAGE 2 - GENERAL PRODUCT INFORMATION

PAGE 3 - IN-PROCESS - DURING COMPRESSION

PAGE 7 - BULK FINISHED PRODUCT - AFTER COMPRESSION

PAGE 17 - REGULATORY SPECIFICATIONS AND METHODS

PAGE 19 - PACKAGED PRODUCT SPECIFICATIONS AND TEST PROCEDURES


<PAGE>   28
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION

                                AFTER COMPRESSION

SAMPLING

This sample is the composite of in-process samples collected during the
compression of the lot and shall consist of at least [***] tablets.

TESTS

     Description

         Specification:   A white, round,  flat-face,  beveled-edge,  compressed
                          tablet,  [***] mm in  diameter  and [***] mm  thick.
                          One side is engraved  AHR-[***],  the obverse  side is
                          scored.  Odor shall be characteristic of product.

         Test:            [***]

     Weight (Average of [***] Tablets)

         Specification:    Theoretical average weight          [***]
                           Acceptable range                    [***]

         Test:             Record the average tablet weight of [***] tablets as
                           determined from [***].

     Dissolution - Glycopyrrolate

         Specification:    [***]

         Principle         [***]

         Reagants          [***]

         Calculation       [***]

Discussion

Start-up and Shut-down of System

         [***]


<PAGE>   29
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION

         Specification:     [***]

         Reagants:          [***]

         Procedure          [***]

         Calculation        [***]

                            [***]

         Calculation        [***]

     Discussion

     Start-up and Shut-down of System


     [***]


         Specification:    [***]

         Reagents          [***]

         Procedure         [***]

         Calculation       [***]



     [***]

Uniformity of Dosage Units

         Method:           [***]

         Specification:    [***]


<PAGE>   30
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION


         Test:             [***]

                           Principles       [***]

                           Apparatus        [***]


                           Reagents         [***]

                           Procedure        1.       [***]
                                            2.       [***]
                                            3.       [***]

                           Calculation               [***]




<PAGE>   31
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



                                      [***]


<PAGE>   32


                                        [***] - CONFIDENTIAL TREATMENT REQUESTED


        BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



                                      [***]




<PAGE>   33

                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION


ACCEPT/REJECT

[***]

1.       [***]

2.       [***]

<PAGE>   34
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION


INSPECTION

During the packaging of the product at A. H. Robins Company, the following
[***].

PRODUCT IDENTIFICATION

[***]

SHELF SAMPLE

[***]

NET CONTENTS OF CONTAINERS

         Specification:                     [***]

         Test:                              [***]

BOTTLES AND CAPS

         Specification:                     Complies with standard

         Test:                              Each bottle sampled shall be
                                            examined for the following:

                                            1.       [***]
                                            2.       [***]
                                            3.       [***]
                                            4.       [***]
                                            5.       [***]
                                            6.       [***]
                                            7.       [***]


<PAGE>   35
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION


LABELS

         Specification:                     Complies with standard

         Test:                              The label of each bottle sampled
                                            shall be examined for the following:

                                            1.       [***]
                                            2.       [***]
                                            3.       [***]
                                            4.       [***]
                                            5.       [***]

CARTONS

         Specification:                     Complies with standard

         Test:                              Each carton sampled shall be
                                            examined for the following:

                                            1.       [***]
                                            2.       [***]
                                            3.       [***]
                                            4.       [***]
                                            5.       [***]

INSERTS

         Specification:                     Complies with standard

         Test:                              The insert of each bottle sampled
                                            shall be examined for the following:

                                            1.       [***]
                                            2.       [***]
                                            3.       [***]
                                            4.       [***]


<PAGE>   36
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

                           GENERAL PRODUCT INFORMATION


STANDARDS

[***]

ACCEPT/REJECT

[***]

1.       [***]

2.       [***]

Specification Approved                               May, 1990

Robert W. Alexander, Jr.                     A. Edwin Martin
Director, Quality Assurance                  Vice President, GMP
A. H. Robins Company                         A. H. Robins Company


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



<PAGE>   37
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



                                     GRAPHIC
                                    WHITEHALL
                                     ROBINS


                                WHITEHALL ROBINS
                      ANALYTICAL DEVELOPMENT - TEST METHOD


Method:                    [***]

WH#/Product:               [***]

Method#:                   [***]

Date:

Supersedes:                [***]

Developed by:              [***]

Checked by:

Reviewed by:





<PAGE>   38
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES

--------------------------------------------------------------------------------
GRAPHIC                       ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------


                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                                Date:    [***]

Method#: [***]                                         Supersedes:      [***]
--------------------------------------------------------------------------------

COMPOSITE ASSAY FOR GLYCOPYRROLATE                            [***]

Reagents

[***]

Apparatus

[***]

Preparation of Standard Solution

NOTE:  Prepare this solution fresh daily.

1.       [***]

2.       [***]

3.       [***]

4.       [***]

<PAGE>   39
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES

--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                           Date:    [***]

Method#: [***]                                           Supersedes:      [***]
--------------------------------------------------------------------------------

Preparation of Sample Solution

1.       [***]

2.       [***]

3.       [***]

4.       [***]

5.       [***]

Procedure

1.       [***]

2.       [***]

3.       [***]

4.       [***]

5.       [***]



<PAGE>   40
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES

--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                             Date:    [***]

Method#: [***]                                      Supersedes:      [***]
--------------------------------------------------------------------------------

6.       [***]

7.       [***]

Manual Calculations
[***]


<PAGE>   41
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                               Date:    [***]

Method#: [***]                                        Supersedes:      [***]
--------------------------------------------------------------------------------









where:

         Au       =        absorbance of sample
         As       =        absorbance of standard
         Ws       =        weight of standard, in mg
         n        =        number of tablets used

CONTENT UNIFORMITY FOR [***]         [***]

Reagents

Refer to section under [***].

Apparatus

Refer to section under [***].

Preparation of Standard Solution

Refer to section under [***].


<PAGE>   42
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                                 Date:    [***]

Method#: [***]                                          Supersedes:      [***]
--------------------------------------------------------------------------------

Preparation of Sample Solution

1.       [***]

2.       [***]

3.       [***]

4.       [***]

Procedure

Refer to section under [***].

Manual Calculations

[***]

For [***] tablets:




<PAGE>   43
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                               Date:    [***]

Method#: [***]                                         Supersedes:      [***]
--------------------------------------------------------------------------------


                                                       [***]















For [***] tablets:

                                                       [***]

<PAGE>   44
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES



--------------------------------------------------------------------------------
GRAPHIC                    ANALYTICAL DEVELOPMENT - TEST METHOD
--------------------------------------------------------------------------------

                                       Robinul Tablets, Robinul Forte Tablets
WH#:     [***]                                  Date:    [***]

Method#: [***]                                            Supersedes:      [***]
--------------------------------------------------------------------------------


                                                       [***]













where:

         Au       =        absorbance of sample
         As       =        absorbance of standard
         Ws       =        weight of standard, in mg


<PAGE>   45
                                        [***] - CONFIDENTIAL TREATMENT REQUESTED

            BULK FINISHED PRODUCT SPECIFICATIONS AND TEST PROCEDURES

                                  SCHEDULE 5.1

                             INITIAL PURCHASE PRICES


Product           Strength  Package Size      AHP NDC#   Initial Purchase Price

<TABLE>
<S>               <C>       <C>                <C>       <C>
Robinul tablets   1 mg      bottles of 100     7824-63   $ [***]
Robinul tablets   2 mg      bottles of 100     7840-63   $ [***]
Robinul tablets   2 mg             bulk           N/A    $ [***] per [***]
Robinul tablets   2 mg             bulk           N/A    $ [***] per [***]
</TABLE>

<PAGE>   46

                                    EXHIBIT G

                               PENDING LIABILITIES

1.   The following civil actions are pending with respect to AHP's sale of the
     Product in the Territory:

                  Shimshock v. Truta, et al., Superior Court of California,
                  County of San Mateo, No. 400614