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                                                                    EXHIBIT 10.5

                           *** CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN
                           THIS DOCUMENT (INDICATED BY ASTERISKS) HAS BEEN
                           OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
                           EXCHANGE COMMISSION PURSUANT TO A REQUEST FOR
                           CONFIDENTIAL TREATMENT UNDER 17 C.F.R. SECTIONS
                           200.80(B)(4), 200.83 AND 230.406.

                           OMEPRAZOLE SUPPLY AGREEMENT

This Omeprazole Supply Agreement (the "AGREEMENT") is made as of this 25th day
of September, 2003 (the "EFFECTIVE DATE") by and among SANTARUS, INC.
("SANTARUS"), a corporation of Delaware located at 10590 W. Ocean Air Drive,
Suite 200, San Diego, CA 92130, INTERCHEM TRADING CORPORATION d/b/a INTERCHEM
CORPORATION ("INTERCHEM"), a corporation of New Jersey located at 120 Route 17
North, Paramus, New Jersey 07652 and UNION QUIMICO FARMACEUTICA, S.A.
("UQUIFA"), a corporation of Spain located at Mallorca, 262, 08008, Barcelona,
Spain.

WHEREAS, UQUIFA is a manufacturer of Omeprazole (Chemical Abstract No.
73590-58-6) and wishes to manufacture and supply Omeprazole to SANTARUS;

WHEREAS, INTERCHEM imports, warehouses, exports and sells Omeprazole
manufactured by UQUIFA; and

WHEREAS, SANTARUS desires a supply of commercial quantities of Omeprazole.

NOW, THEREFORE, in consideration of the mutual covenants set forth herein,
INTERCHEM, UQUIFA and SANTARUS( each, a "PARTY" and, collectively, the
"PARTIES") agree as follows.

1.       SCOPE OF AGREEMENT

1.1.     This Agreement shall apply to all purchases of Omeprazole by SANTARUS
         from UQUIFA during the term of this Agreement.

1.2.     This Agreement does not constitute a purchase order. Purchases under
         this Agreement shall be made only with purchase orders issued by
         SANTARUS to INTERCHEM (each, a "PURCHASE ORDER"). The Purchase Order
         shall set forth the quantities of Omeprazole desired, the desired
         delivery date and the desired destination for delivery and shall be in
         the form attached hereto as Appendix A. All terms and conditions of the
         Purchase Orders shall apply, provided that in the event of a conflict
         between the terms of any Purchase Order, order acknowledgement,
         packaging slip or other documentation, and the terms of this Agreement,
         the terms of this Agreement shall control, unless such documentation
         specifically states that it overrides conflicting terms of this
         Agreement arid is signed by each of the Parties.

1.3.     All Omeprazole sold by INTERCHEM on behalf of UQUIFA to SANTARUS will
         be manufactured by UQUIFA in accordance with the terms of this
         Agreement.


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2.       MANUFACTURING; OMEPRAZOLE SPECIFICATIONS

2.1.     UQUIFA shall manufacture the Omeprazole supplied to SANTARUS in
         accordance with (a) the specifications set forth on Schedule A attached
         hereto, and (b) the specifications, methods, processes and procedures,
         including site of manufacture, set forth in UQUIFA's drug master file
         (DMF No. 11551) ("DMF") as filed with the U.S. Food and Drug
         Administration ("FDA") (both (a) and (b), including any modifications
         approved in accordance with Section 2.2 hereof collectively, the
         "SPECIFICATIONS"). If UQUIFA wishes to make any change to the
         Specifications (including, but not limited to, any change that could
         affect the purity, potency, identity and/or physical properties of the
         Omeprazole or the site of its manufacture), it shall notify SANTARUS in
         writing in advance thereof and comply with the requirements of Section
         2.2 prior to implementing such change. Such notification shall describe
         the proposed change in sufficient detail so as to permit SANTARUS to
         understand the reasons for the proposed change and evaluate the impact
         of such change on its development plans, its plans to seek regulatory
         approval and its commercialization plans with respect to finished
         dosage form products (the "FINISHED PRODUCTS").

2.2.     Without limiting the generality of the foregoing provisions, neither
         UQUIFA nor INTERCHEM may change the Specifications unless (a) SANTARUS
         has agreed in writing to such change (which agreement SANTARUS may not
         unreasonably withhold), or (b) such change is required by (1) any
         regulatory agency which has jurisdiction over SANTARUS, UQUIFA and/or
         any of the Finished Products, or (2) by the U.S. Pharmacopoeia. If any
         change to the Specifications requires the approval of the FDA, other
         governmental agency or any foreign regulatory agency equivalent to the
         FDA, each having jurisdiction over Omeprazole, the Finished Products or
         SANTARUS' marketing of Finished Products (each a "REGULATORY AGENCY"),
         such change shall not be implemented until each Regulatory Agency has
         approved such change in writing and SANTARUS has had sufficient time to
         adopt and implement such change into its operations, including but not
         limited to any manufacturing of the Finished Products by SANTARUS'
         designated contract manufacturers. For the avoidance of doubt, neither
         UQUIFA nor INTERCHEM shall supply to SANTARUS hereunder, and SANTARUS
         shall have no obligation to accept any Omeprazole from UQUIFA or
         INTERCHEM manufactured in contravention of this Section 2.2.

2.3.     INTERCHEM and UQUIFA will take commercially reasonable steps necessary
         to enable SANTARUS to secure from the relevant Regulatory Agencies
         approval of UQUIFA as a source of supply of Omeprazole for SANTARUS'
         Finished Products to be marketed anywhere in the world. Without
         limiting the generality of the foregoing, INTERCHEM will supply to
         SANTARUS, as soon as possible, sufficient quantities of Omeprazole to
         enable SANTARUS to support the filing of one or more New Drug
         Application (the "NDA") (or Abbreviated New Drug Application, if
         applicable), together with all amendments and supplements thereto,
         referencing UQUIFA as its supplier of Omeprazole for its initial
         Finished Product candidate. UQUIFA will be responsible for


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         procuring and maintaining all regulatory filings and any other
         compliance efforts, including without limitation, the DMF, related to
         Omeprazole that are required in order to obtain approval from the FDA
         of SANTARUS' NDAs referencing Omeprazole and equivalent approvals from
         Regulatory Agencies in other jurisdictions, at no additional cost to
         SANTARUS.

2.4.     UQUIFA shall test, or have tested, each lot of Omeprazole shipped to
         SANTARUS using the analytical testing methodologies which are set forth
         in the Specifications. With each shipment of Omeprazole, UQUIFA or
         INTERCHEM shall deliver to SANTARUS certificates of analysis and
         compliance from UQUIFA (a) stating that the Omeprazole being shipped
         has been tested and does conform to the Specifications, (b) setting
         forth in detail the testing methodology employed by UQUIFA in making
         the foregoing determination and the results generated by such tests,
         and ( c) confirming compliance with the current good manufacturing
         practices ("CGMP") required by the FDA, and other relevant Regulatory
         Agencies in those jurisdictions of which SANTARUS has given UQUIFA
         notice, with respect to the manufacture and testing of Omeprazole for
         use as an active pharmaceutical ingredient in the Finished Products and
         subsequent sale in such jurisdictions.

3.       FORECASTS

3.1.     In order to assist INTERCHEM and UQUIFA in planning the production runs
         for Omeprazole, SANTARUS shall use its commercially reasonable efforts
         to provide to UQUIFA and INTERCHEM, at least           ***

                          ***           of the quantities of Omeprazole required
         by SANTARUS, *** period. SANTARUS shall deliver the first such forecast
         to INTERCHEM and UQUIFA as soon as reasonably practicable following the
         execution of this Agreement, and will update the forecast every ***
         thereafter. SANTARUS may, at its discretion, update such forecast more
         frequently. It is understood that all such forecasts are intended to be
         SANTARUS' estimates of its purchase requirements and they shall not be
         binding upon SANTARUS; however, UQUIFA and INTERCHEM shall, at minimum,
         supply the amounts specified in Section 3.3.

3.2.     After the Finished Products have received approval for marketing from a
         Regulatory Agency and have been made generally commercially available
         (hereinafter "COMMERCIAL LAUNCH"), UQUIFA and INTERCHEM shall, within
         *** days after SANTARUS has provided its *** forecast, notify SANTARUS
         in writing of any prospective problems it might have with respect to
         supplying SANTARUS' forecasted order quantities. Upon receipt of such
         notice, the Parties shall promptly discuss the inability to supply the
         amounts forecasted by SANTARUS and work in good faith to agree upon
         revised forecast amounts. ***
                                            ***

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

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3.3.     Subject to the lead-time requirements specified in Schedule B, UQUIFA
         and INTERCHEM shall deliver to SANTARUS' designated facility during any
         given month, pursuant to Purchase Orders provided under Section 3.4,
         the amount specified in the Purchase Order therefor, which amount may
         be                     ***
                                       ***
                                       ***
         (the "SUPPLY COMMITMENT"). In addition, UQUIFA and INTERCHEM shall use
         their best efforts to deliver any and all ordered amounts in excess of
         the Supply Commitment.

3.4.     SANTARUS shall provide to UQUIFA and INTERCHEM Purchase Orders for
         Omeprazole within the lead times set forth in Schedule B. Within ten
         (10) business days after the date that a Purchase Order is submitted
         (the "ORDER DATE"), INTERCHEM and UQUIFA shall acknowledge receipt of
         SANTARUS' Purchase Order and confirm that the amounts of Omeprazole
         ordered in the Purchase Order, subject to Section 3.3., will be timely
         supplied.

3.5.     UQUIFA and INTERCHEM agree to retain a                 ***

                   ***    .  ***    of safety stock will be held by INTERCHEM in
         the United States and *** of safety stock will be held by UQUIFA in
         Spain. UQUIFA AND INTERCHEM will promptly notify SANTARUS if UQUIFA's
         manufacturing capacity will be insufficient to fill a Purchase Order
         submitted by SANTARUS. Such notice will include the expected duration
         of the shortage and its impact on the supply of Omeprazole to SANTARUS.
         Such notification shall not operate to relieve UQUIFA or INTERCHEM of
         their obligations to deliver the ordered amounts of Omeprazole or
         affect SANTARUS' right to pursue any remedies that may be available to
         it. UQUIFA and INTERCHEM will use their best efforts to mitigate the
         impact on SANTARUS of shortages or other constrained capacity. The
         obligations of UQUIFA and INTERCHEM to maintain the safety stock
         specified herein shall commence as of the Commercial Launch.

4.       ORDER; DELIVERY

4.1.     Each Purchase Order for Omeprazole shall specify the quantity of
         Omeprazole ordered and the required delivery date and destination,
         consistent with the terms of this Agreement. Such delivery dates are
         "on dock" at SANTARUS' designated facility for such delivery.
         Deliveries must be made on normal business days of the designated
         facility unless otherwise coordinated.

4.2.     Subject to any agreement between SANTARUS and INTERCHEM and UQUIFA to
         the contrary, all orders shall be dispatched by UQUIFA to INTERCHEM,
         and INTERCHEM shall make all necessary shipping arrangements to
         SANTARUS' designated facility. Freight terms shall be as set forth in
         Schedule C.

4.3.     INTERCHEM and UQUIFA shall deliver the complete order amounts on the
         delivery date specified in the Purchase Order. Following receipt of any
         Omeprazole from UQUIFA, INTERCHEM shall be responsible for the
         warehousing of the Omeprazole in

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

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         the United States and for coordinating the import/export of the
         Omeprazole to the United States and to SANTARUS' designated
         manufacturing facilities (which are currently located in the United
         States and Canada) in a timely manner and in compliance with the
         Specifications and all Applicable Laws (as defined in Section 8.1.1).
         INTERCHEM and UQUIFA shall notify SANTARUS of the expected delivery
         date of the order to enable receipt to be coordinated.

4.4.     Subject to clearance by customs and, if required, the FDA, the
         Omeprazole shall be delivered to SANTARUS' designated facility in
         UQUIFA's normal packaging and documentation for Omeprazole, including
         without limitation cold storage procedures, as reflected in UQUIFA's
         DMF, provided that such packaging and documentation shall meet the
         customs and regulatory requirements within the United States and/or
         Canada, as applicable to the location of SANTARUS' designated facility
         for delivery. Each shipment shall include certificates of analysis and
         compliance, which include, without limitation, a statement of
         compliance with cGMP, and such other documentation and ` information as
         may be necessary or desirable for complying with import, export and
         customs laws, regulations and requirements as applicable.

5.       EXCLUSIVITY; PRICE; PAYMENT

5.1.     Subject to Section 5.4, SANTARUS agrees to *** of its Omeprazole
         intended for commercial sale from INTERCHEM and UQUIFA during the term
         of this Agreement (the " *** Obligation").             ***
                                                                ***
                                            ***

5.2.     The price for the Omeprazole to be purchased by SANTARUS hereunder is
         set forth in Schedule C, as adjusted in accordance with Section 5.3
         hereof (the "Price").

5.3.     The Price shall be in effect for the *** following the Effective Date
         and shall be renegotiated by SANTARUS, on the one hand, and INTERCHEM
         and UQUIFA, on the other hand, in good faith on *** reasonably in
         advance of the expiration of the applicable *** period and taking into
         account then prevailing market conditions.

5.4.     SANTARUS shall have no further obligation to comply with the ***
         Obligation under the following circumstances:

         (a)      in the event of breach by INTERCHEM or UQUIFA of any of the
                  terms set forth herein which breach is not cured within the
                  period set forth in Section 11.2; or

         (b)      in the event that the Parties are unable to agree on an annual
                  adjustment to the Price (as contemplated by 5.3) by at least
                        ***     prior to the expiration of the applicable    ***
                  period.

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

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         In the event the       ***     Obligation terminates pursuant to
         Section 5.4(a) or 5.4(b), INTERCHEM and UQUIFA shall be obligated to
         continue to perform under the terms hereof at the most recent previous
         Price agreed on by the Parties.

5.5.     INTERCHEM shall issue its invoice to SANTARUS at the time of shipment.
         Each invoice shall set forth, in U.S. Dollars, the applicable Price for
         the shipment properly determined in accordance with the provisions of
         this Agreement. Payment of the invoice by SANTARUS shall be within ***
         days following receipt of such invoice. Payment shall be subject to the
         inspection and acceptance procedures set forth in Section 6. SANTARUS
         may withhold a portion of any invoice that it disputes in good faith
         pending resolution of such dispute. All invoices and payments shall be
         in U.S. Dollars.

6.       INSPECTION OF SHIPMENTS

6.1.     SANTARUS shall visually inspect or have visually inspected the
         Omeprazole delivered hereunder for obvious damage and/or shortage
         (collectively, "OBVIOUS DAMAGE") immediately upon receipt and shall
         provide INTERCHEM and UQUIFA with written notice of any such Obvious
         Damage within   ***   days after receipt. SANTARUS shall be deemed to
         have accepted any shipment of Omeprazole but only with respect to
         Obvious Damage, unless INTERCHEM or UQUIFA receives the written notice
         required within the   **   -day time period specified above. At its
         discretion, SANTARUS may also test, or have tested, any lot of
         Omeprazole supplied to SANTARUS.

6.2.     At any time within   ***   after receipt of any lot of Omeprazole but
         promptly after discovery, SANTARUS may provide INTERCHEM with written
         notice of any non-obvious damage, including adulteration of the
         Omeprazole, failure to meet Specifications, or other latent damage
         (collectively, "NON-OBVIOUS DAMAGE"). Obvious Damage and Non-Obvious
         Damage shall hereinafter be collectively referred to as "DAMAGE".

6.3.     SANTARUS may reject any portion of any shipment of Omeprazole which
         contains any Damage by providing written notice to UQUIFA of its
         rejection. SANTARUS agrees to provide UQUIFA's Quality Control
         Department with documentation of Damage to confirm the existence
         thereof in connection with any notice of rejection.

6.4.     If UQUIFA and SANTARUS disagree as to the existence of Damage, then
         they will
                                                           ***
                                                           ***
                                                           ***
                                  ***

6.5.     Provided SANTARUS provides notice of the damage claimed within    ***
         days of receipt of the allegedly Damaged Omeprazole in the case of
         Obvious Damage and within    ***    of receipt of the allegedly Damaged
         Omeprazole in the case of Non-Obvious Damage, whether or not UQUIFA
         accepts SANTARUS' basis for rejection, promptly on receipt of a notice
         of rejection and/or shortage, UQUIFA and INTERCHEM

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

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         shall, at SANTARUS' request, and at no additional cost to SANTARUS,
         deliver to SANTARUS quantities of replacement Omeprazole equal to the
         rejected or short quantities as soon as reasonably practicable
         thereafter, and in no event more than   ***   days after such notice is
         given. UQUIFA and INTERCHEM will use expedited means of transport, if
         so requested by SANTARUS                ***
                        ***

6.6.     Notwithstanding any other provisions of this Agreement, SANTARUS
         agrees, if so requested by UQUIFA, to return to UQUIFA, at UQUIFA's
         expense, any Omeprazole that is, or is claimed to be, Damaged or
         otherwise to dispose of such Omeprazole as UQUIFA may request.

7.       CONFIDENTIALITY

7.1.     During the term of this Agreement, the Parties may disclose certain
         confidential and proprietary information and data to each other
         relating to their respective products, including active pharmaceutical
         ingredients and Finished Products ("PRODUCTS") and businesses,
         including, but not limited to financial and other business information,
         Product samples, formulas, manufacturing processes, specifications,
         drawings, schematics and other technical, customer and Product
         development plans, forecasts, strategies and other data. Except as
         otherwise specifically provided herein, all information disclosed by
         one Party (in such capacity, the "DISCLOSING PARTY") to the other Party
         (in such capacity, the "RECEIVING Party") relating to the Disclosing
         Party's Products and/or its business operations and the results,
         reports, etc., of testing and evaluation of any such information shall
         constitute "PROPRIETARY INFORMATION."

7.2.     Proprietary Information disclosed by a Disclosing Party to a Receiving
         Party hereunder shall be used by the Receiving Party solely in
         connection with exercising its rights or performing its obligations
         under this Agreement.

7.3.     In consideration of the Disclosing Party's disclosure and supply of
         Proprietary Information, each Party, as a potential Receiving Party,
         agrees that, for the term of the Agreement and for a period of ***
         years thereafter, it shall use the Disclosing Party's Proprietary
         Information exclusively to conduct the activities contemplated under
         this Agreement. Each Party further agrees, as a potential Receiving
         Party, for the term of the Agreement and for a period of *** years
         thereafter, it shall not disclose, without the express written consent
         of the Disclosing Party, any Proprietary Information, including this
         Agreement or the interest of the Disclosing Party in exploring the
         possibility of entering into a business relationship with the Receiving
         Party, to any person other than to those employees, consultants or
         agents of the Receiving Party ("REPRESENTATIVES") who will be directly
         involved in fulfilling the Receiving Party's obligations under this
         Agreement, provided that such Representatives have assumed like
         obligations of confidentiality in writing to the Disclosing Party.
         Notwithstanding the foregoing, (a) SANTARUS may disclose the existence
         and terms of this Agreement to bona fide potential investors,
         acquirers, corporate partners and financial advisors and (b) UQUIFA

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

                                       7
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         may disclose the existence (but not the terms of) this Agreement to
         bona fide potential investors and financial advisors.

7.4.     Each Party, as a potential Receiving Party, agrees to advise those of
         its Representatives who receive Proprietary Information (and such other
         persons who may receive Proprietary Information as permitted by 7.3(a)
         or 7.3(b) above) that such information (a) is proprietary and
         confidential to the Disclosing Party and (b) shall not be disclosed to
         anyone except as authorized herein. Each Party further agrees to take
         such reasonable precautions as it normally takes with its own
         confidential and proprietary information to prevent unauthorized
         disclosure or use of such Proprietary Information.

7.5.     In the event that the Receiving Party is required by any government
         regulation, law, court order or rule or otherwise becomes legally
         compelled to disclose any Proprietary Information, it will provide the
         Disclosing Party with prompt advance notice in writing so that the
         Disclosing Party may, at its discretion, reasonably intervene prior to
         disclosure. The Receiving Party will exercise its commercially
         reasonable efforts to obtain reliable assurance that confidential
         treatment will be accorded to such Proprietary Information.

7.6.     Notwithstanding any of the foregoing, the term "Proprietary
         Information" and the obligation of confidentiality associated therewith
         shall not apply to the following information: (a) information which, at
         the time of the Disclosing Party's disclosure to the Receiving Party,
         is publicly known; (b) information which, after the Disclosing Party's
         disclosure to the Receiving Party, becomes publicly known, except where
         such knowledge is the result of the Receiving Party's breach of this
         Agreement or otherwise is the result of any unauthorized disclosure by
         any of its employees or Representatives; (c) information which, prior
         to the Disclosing Party's disclosure to the Receiving Party, was
         already in the Receiving Party's possession, as evidenced by its prior
         written records; or (d) information which, subsequent to the Disclosing
         Party's disclosure to the Receiving Party, is obtained by the Receiving
         Party from a third Party which is lawfully in possession of such
         information and not subject to a contractual or fiduciary relationship
         to the Disclosing Party with respect thereto.

7.7.     Upon the termination of this Agreement, the Receiving Party shall, if
         so requested by the Disclosing Party, promptly return to the Disclosing
         Party the originals and all copies of any Proprietary Information then
         in the Receiving Party's possession. Notwithstanding the foregoing,
         Receiving Party may retain one copy of such Proprietary Information for
         archival purposes.

8.       QUALITY OF OMEPRAZOLE; REGULATORY MATTERS; REPRESENTATIONS AND
         WARRANTIES

8.1.     UQUIFA hereby represents, warrants and covenants as follows:

         8.1.1.   At all times during the term of this Agreement, UQUIFA's
                  facilities shall remain in compliance with, and the Omeprazole
                  shall be manufactured and delivered in compliance with, all
                  applicable laws, regulations and standards, including but not
                  limited to, the provisions of the Federal Food, Drug and
                  Cosmetic Act, as

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                  amended from time to time (the "Act"); the FDA's cGMP
                  including the FDA's Guidance for Industry, Manufacturing,
                  Processing or Holding Active Pharmaceutical Ingredients, March
                  1998, and any updates thereto; FDA's regulations for drug
                  establishment registration; the Specifications; the other
                  rules and regulations promulgated under the Act relating to
                  the manufacture of pharmaceutical products; and equivalent
                  laws, regulations and standards promulgated by Regulatory
                  Agencies in all jurisdictions for which SANTARUS has given
                  notice to UQUIFA (collectively, the "Applicable Laws").

         8.1.2.   No Omeprazole constituting or being a part of any shipment to
                  SANTARUS shall at the time of any such shipment be adulterated
                  within the meaning of the Act, or the rules and regulations
                  promulgated thereunder, as such law, rule or regulation is
                  constituted and in effect at the time of any such shipment.

         8.1.3.   All Omeprazole supplied to SANTARUS hereunder (i) shall comply
                  with the Specifications; (ii) shall have been manufactured,
                  stored and shipped in accordance with the Specifications,
                  applicable approvals from Regulatory Agencies and all
                  Applicable Laws, (iii) may be introduced into public commerce
                  consistent with the intended use for Omeprazole pursuant to
                  Applicable Laws, and (iv) will have expiration dating of not
                  less than       ***      .

         8.1.4.   All necessary licenses, permits or approvals required by
                  Applicable Laws in connection with the manufacture, storage,
                  and shipment of Omeprazole, including without limitation
                  permits related to manufacturing facilities shall be obtained
                  and maintained.

         8.1.5.   UQUIFA will (i) respond fully and accurately to all inquiries
                  directed to it by the FDA or any other Regulatory Agency that
                  may impact the quality or timely delivery of Omeprazole and
                  promptly notify SANTARUS of same, (ii) assist SANTARUS in
                  responding to inquiries directed to SANTARUS by the FDA or
                  other Regulatory Agencies, and (iii) provide the FDA or other
                  Regulatory Agencies with such information and data as is
                  requested by the FDA or other Regulatory Agencies with respect
                  to the manufacture, use, route of synthesis and testing of the
                  Omeprazole.

         8.1.6.   UQUIFA's DMF is current and acceptable to the FDA and UQUIFA's
                  manufacturing facilities are in compliance with the FDA's
                  cGMP.

         8.1.7.   UQUIFA has disclosed to SANTARUS all warning letters or
                  similar notices relating to its manufacturing facilities or
                  import alerts (including FDA Form 483's), if any, for products
                  manufactured in its facilities issued         ***     and
                  UQUIFA will during the term disclose in timely fashion all
                  such letters, alerts and notices.

         8.1.8.   UQUIFA has, and shall maintain, sufficient facilities,
                  personnel and resources to meet its obligations to supply
                  Omeprazole under this Agreement.

*** Portions of this page have been omitted pursuant to a request for
Confidential Treatment and filed separately with the Commission.

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         8.1.9.   UQUIFA is not aware of any claim by a third party that the
                  Omeprazole supplied hereunder or its process for manufacturing
                  the Omeprazole supplied hereunder would, if carried out in the
                  United States, Canada or Spain or in any other country where
                  generic Omeprazole is manufactured or sold, infringe,
                  misappropriate or violate any patent, trade secret or other
                  intellectual property right in effect in such countries.

         8.1.10.  To UQUIFA's knowledge (after reasonable inquiry and
                  investigation), the Omeprazole supplied to SANTARUS under this
                  Agreement and UQUIFA's process for manufacturing the
                  Omeprazole supplied hereunder will not infringe,
                  misappropriate or violate any patent, trade secret or other
                  intellectual property right in effect during the term of this
                  Agreement in the United States, Canada or Spain.

         8.1.11.  There are no pending or threatened claims against UQUIFA
                  asserting that any of the activities of UQUIFA relating to the
                  manufacture, import, use and sale of Omeprazole in the United
                  States, Canada or Spain or the conduct of the activities
                  contemplated herein by SANTARUS, infringe, misappropriate or
                  violate the rights of any third party.

8.2.     INTERCHEM hereby represents, warrants and covenants as follows:

         8.2.1.   At all times during the term of this Agreement, INTERCHEM's
                  facilities shall remain in compliance with, and following
                  delivery by UQUIFA, the Omeprazole shall be shipped and stored
                  in compliance with, the Specifications and all Applicable
                  Laws.

         8.2.2.   INTERCHEM shall not cause any Omeprazole shipped to SANTARUS
                  to, at the time of any such shipment, be adulterated within
                  the meaning of the Act, or the rules and regulations
                  promulgated thereunder, as such law, rule or regulation is
                  constituted and in effect at the time of any such shipment.

         8.2.3.   All necessary licenses, permits or approvals required by
                  Applicable Laws in connection with the storage and shipment of
                  Omeprazole by INTERCHEM shall be obtained and maintained.

         8.2.4.   INTERCHEM will (i) respond fully and accurately to all
                  inquiries directed to it by the FDA or any other Regulatory
                  Agency that may impact the quality or timely delivery of
                  Omeprazole and promptly notify SANTARUS of same, (ii) assist
                  SANTARUS in responding to inquiries directed to SANTARUS by
                  the FDA or other Regulatory Agencies, and (iii) provide the
                  FDA or other Regulatory Agencies with such information and
                  data as is requested by the FDA or other Regulatory Agencies
                  with respect to the manufacture, use, route of synthesis and
                  testing of the Omeprazole.

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<PAGE>

         8.2.5.   INTERCHEM has disclosed to SANTARUS any and all warning
                  letters or similar notices relating to its shipping and/or
                  storage facilities or import alerts (including FDA Form
                  483's), if any, issued        ***     and INTERCHEM will
                  during the term continue to disclose in timely fashion all
                  such notices.

         8.2.6.   INTERCHEM has, and shall maintain, sufficient facilities,
                  personnel and resources to meet its obligations under this
                  Agreement.

         8.2.7.   INTERCHEM is not aware of any claim by a third party that
                  UQUIFA's process for manufacturing the Omeprazole supplied
                  hereunder would, if carried out in the United States, Canada
                  or Spain or in any other country where generic Omeprazole is
                  manufactured or sold, infringe, misappropriate or violate any
                  patent, trade secret or other intellectual property right in
                  effect in such countries.

         8.2.8.   To INTERCHEM's knowledge (after reasonable inquiry and
                  investigation), UQUIFA's current process for manufacturing the
                  Omeprazole supplied hereunder and the Omeprazole supplied
                  utilizing such process does not infringe, misappropriate or
                  violate any patent, trade secret or other intellectual
                  property right in effect during the term of this Agreement in
                  the United States.

         8.2.9.   There are no pending or threatened claims against INTERCHEM
                  asserting that any of the activities of INTERCHEM relating to
                  the manufacture, import, use and sale of Omeprazole in the
                  United States, Canada or Spain or the conduct of the
                  activities contemplated herein by SANTARUS, infringe,
                  misappropriate or violate the rights of any third party.

8.3.     SANTARUS hereby represents, warrants and covenants to SANTARUS'
         knowledge (after reasonable inquiry and investigation), the Finished
         Product will not infringe, misappropriate or violate any third party
         patent, trade secret or other intellectual property right in effect
         during the term of this Agreement in the United States or Canada
         (provided, that SANTARUS' representation does not extend to any
         infringement, misappropriation or violation that arises out of or
         relates to the Omeprazole or the process for manufacturing the
         Omeprazole).

8.4.     Each Party represents and warrants that all corporate action on its
         part and on the part of each of its officers and directors necessary
         for the authorization, execution and delivery of this Agreement has
         been taken, it has the full right and authority to enter into this
         Agreement and perform its obligations hereunder and that it is not
         aware of any obligations owed to third parties that would conflict with
         its ability to perform its obligations hereunder.

8.5.     If requested in writing by SANTARUS (which request shall be delivered
         to both UQUIFA and INTERCHEM), INTERCHEM and UQUIFA shall permit
         SANTARUS or its authorized representatives to inspect INTERCHEM's
         and/or UQUIFA's facilities and records and be given access to
         INTERCHEM's and/or UQUIFA's personnel (at reasonable times, upon
         reasonable advance notice and in the company of an

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                                       11

<PAGE>

         INTERCHEM or UQUIFA representative, as the case may be, during normal
         business hours), to the extent SANTARUS deems reasonably necessary to
         enable SANTARUS to verify compliance by INTERCHEM and/or UQUIFA with
         its obligations under this Agreement and to verify compliance with any
         Applicable Laws.

8.6.     UQUIFA and INTERCHEM shall provide to SANTARUS yearly confirmation that
         it has timely filed with the FDA and all other relevant Regulatory
         Agencies, the required Annual Progress Report to UQUIFA's DMF for the
         year then ended.

8.7.     SANTARUS shall provide INTERCHEM and UQUIFA copies of product
         complaints, or notices or inquiries from the FDA or other Regulatory
         Agencies, which raise issues with respect to the manufacture or product
         quality of the Omeprazole provided by UQUIFA to SANTARUS. UQUIFA shall
         fully and appropriately investigate such matters and provide SANTARUS
         with a report of its investigation. In the event that INTERCHEM or
         UQUIFA receives any complaint, claims or adverse reaction reports
         regarding Omeprazole, including notices from the FDA regarding any
         alleged regulatory non-compliance of Omeprazole, such Party shall
         promptly and not more than     ***     after receipt, provide to
         SANTARUS all information contained in the complaint, report or notice
         and such additional information regarding Omeprazole as SANTARUS may
         reasonably request. INTERCHEM and UQUIFA shall comply, at a minimum,
         with FDA requirements for complaint handling with respect to such
         complaints, claims or adverse reaction reports.

8.8.     SANTARUS, INTERCHEM and UQUIFA each further represents and warrants,
         for itself, that it shall comply with all Applicable Laws in the
         performance of its obligations hereunder.

8.9.     UQUIFA and INTERCHEM shall promptly notify SANTARUS of any problems or
         unusual production situations which have, or are reasonably likely to
         have, an adverse effect on UQUIFA's or INTERCHEM's ability to perform
         its obligations hereunder or to deliver the Omeprazole to SANTARUS in a
         timely manner. In addition, UQUIFA and INTERCHEM shall notify and, if
         applicable, provide copies of any notices or communications to,
         SANTARUS of any FDA or other governmental agency inspection,
         investigation or other inquiry or communication relating to the
         manufacture of the Omeprazole or to any facility at which the
         Omeprazole is manufactured, including, but not limited to, any FDA FORM
         483 or warning letter, promptly and not more than *** after UQUIFA or
         INTERCHEM becomes aware of such inspection, investigation or other
         inquiry or communication and shall promptly thereafter provide to
         SANTARUS a written summary of all findings and corrective actions taken
         or planned by UQUIFA or INTERCHEM, including any written responses from
         UQUIFA or INTERCHEM to the FDA or other governmental agency. Such
         notices shall not operate to relieve UQUIFA or INTERCHEM of their
         obligations to deliver the ordered amounts of Omeprazole or affect
         SANTARUS' right to pursue any remedies that might be available to it.

8.10.    INTERCHEM and UQUIFA each covenants that it will not in the performance
         of its obligations under this Agreement use the services of any person
         debarred or suspended

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                                       12

<PAGE>

         under 21 U.S.C. Section 35(a) or (b). INTERCHEM and UQUIFA each
         represents that it does not currently have, and covenants that it will
         not hire, as an officer or an employee, any person who has been
         convicted of a felony under the laws of the United States for conduct
         relating to the regulation of any drug product under the Act.

8.11.    Each party shall maintain insurance as follows:

         8.11.1.  UQUIFA shall maintain commercial general liability insurance
                  and product liability insurance with a minimum limit per
                  occurrence or accident of $ ***  and an annual aggregate limit
                  of $ ***   for the term of this Agreement and for  ***   years
                  thereafter. Upon request, UQUIFA will provide to SANTARUS
                  copies of insurance certificates reflecting the above.

         8.11.2.  INTERCHEM shall maintain commercial general liability
                  insurance and product liability insurance with a minimum limit
                  per occurrence or accident of $ *** and an annual aggregate
                  limit of $ *** for the term of this Agreement and for ***
                  years thereafter. Upon request, INTERCHEM will provide to
                  SANTARUS copies of insurance certificates reflecting the
                  above.

         8.11.3.  SANTARUS shall maintain commercial general liability insurance
                  with a minimum limit per occurrence or accident of $  ***  and
                  an annual aggregate limit of $   ***   and product liability
                  insurance with a minimum limit per occurrence or accident of $
                  ***  and an annual aggregate limit of $  ***  for the term of
                  this Agreement and for  ***  years thereafter. Notwithstanding
                  the foregoing, SANTARUS shall increase its insurance coverage
                  as reasonably prudent in connection with the Commercial
                  Launch. Upon request, SANTARUS will provide to UQUIFA or
                  INTERCHEM copies of insurance certificates reflecting the
                  above.

8.12.    INTERCHEM and UQUIFA shall immediately notify SANTARUS of any
         information of the following kind about Omeprazole provided to
         SANTARUS:

         8.12.1.  information indicating that shipped product has not been
                  manufactured or supplied in accordance with the
                  Specifications, cGMP, this Agreement or in compliance with
                  Applicable Laws; and

         8.12.2.  information concerning any bacteriological contamination, or
                  any significant chemical, physical or other changes or
                  deterioration in the shipped Omeprazole, or the failure of one
                  or more shipped lots of Omeprazole to meet Specifications,
                  including stability parameters.

8.13.    EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, NO PARTY MAKES ANY
         WARRANTIES, EXPRESS, IMPLIED, STATUTORY OR OTHERWISE, AND EACH PARTY
         SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
         PARTICULAR PURPOSE.

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                                       13

<PAGE>

9.       INDEMNIFICATION

9.1.     SANTARUS hereby agrees to and shall defend, indemnify, and hold
         harmless INTERCHEM, UQUIFA, their affiliates and each of their
         respective employees, officers, directors and agents (the "SUPPLIER
         INDEMNITEES"), from, against, and in respect of, any and all losses,
         judgments, damages, liabilities, suits, actions, expenses (including
         reasonable attorney's fees), and proceedings arising from any claims of
         any third party to the extent resulting from:

         9.1.1.   any misrepresentation, breach of warranty, or the
                  non-fulfillment of any obligation, covenant, or duty on the
                  part of SANTARUS under this Agreement;

         9.1.2.   any claim, complaint, suit, proceeding or cause of action
                  against any of the Supplier Indemnitees alleging physical
                  injury or death, brought by or on behalf of an injured party,
                  or loss of service or consortium or a similar such claim,
                  complaint, suit, proceeding or cause of action brought by a
                  spouse, relative or companion of an injured party due to such
                  physical injury or death, and in each case arising out of the
                  Finished Products, except to the extent resulting from (i) any
                  misrepresentation, breach of warranty, or the non-fulfillment
                  of any obligation, covenant, or duty on the part of INTERCHEM
                  or UQUIFA under this Agreement, (ii) any negligence or willful
                  misconduct of the Supplier Indemnitees in performing this
                  Agreement, or (iii) any claim subject to INTERCHEM's and
                  UQUIFA's indemnification obligations under Section 9.2;

         9.1.3.   any negligence or willful misconduct of SANTARUS, its
                  employees, officers and directors in performing this
                  Agreement; and

         9.1.4.   any claim of patent infringement relating to a Finished
                  Product or the process for manufacturing a Finished Product
                  (excluding any claim of patent infringement arising out of or
                  relating to the Omeprazole or the process for manufacturing
                  the Omeprazole), which claim, if true, would be in
                  contravention of the representations, warranties and covenants
                  of SANTARUS hereunder.

9.2.     UQUIFA hereby agrees to and shall defend, indemnify, and hold harmless
         SANTARUS, its affiliates and each of their respective employees,
         officers, directors and agents (the "SANTARUS INDEMNITEES"), from,
         against, and in respect of, any and all losses, judgments, damages,
         liabilities, suits, actions, expenses (including reasonable attorney's
         fees), and proceedings arising from any claims of any third party to
         the extent resulting from:

         9.2.1.   any misrepresentation, breach of warranty, or the
                  nonfulfillment of any obligation, covenant, or duty on the
                  part of UQUIFA under this Agreement;

         9.2.2.   any claim, complaint, suit proceeding or cause of action
                  against any of the Santarus Indemnitees alleging physical
                  injury or death, brought by or on behalf of an injured party,
                  or loss of service or consortium or a similar such claim,
                  complaint, suit, proceeding or cause of action brought by a
                  spouse, relative or

                                       14

<PAGE>

                  companion of an injured party due to such physical injury or
                  death, and in each case arising out of the Omeprazole supplied
                  by INTERCHEM and UQUIFA to SANTARUS, except to the extent
                  resulting from (i) any misrepresentation, breach of warranty,
                  or the non-fulfillment of any obligation, covenant, or duty on
                  the part of SANTARUS under this Agreement, (ii) any negligence
                  or willful misconduct of the Santarus Indemnitees in
                  performing this Agreement, or (iii) any claim subject to
                  SANTARUS' indemnification obligations under Section 9.1;

         9.2.3.   any negligence or willful misconduct of UQUIFA or their
                  respective employees, officers or directors in performing this
                  Agreement; and.

         9.2.4.   any claim of patent infringement relating to the Omeprazole
                  supplied to SANTARUS or the process for manufacturing the
                  Omeprazole supplied to SANTARUS which claim, if true, would be
                  in contravention of the representations, warranties and
                  covenants of UQUIFA hereunder.

9.3.     INTERCHEM hereby agrees to and shall defend, indemnify, and hold
         harmless the Santarus Indemnitees from, against, and in respect of, any
         and all losses, judgments, damages, liabilities, suits, actions,
         expenses (including reasonable attorney's fees), and proceedings
         arising from any claims of any third party to the extent resulting
         from:

         9.3.1.   any misrepresentation, breach of warranty, or the
                  nonfulfillment of any obligation, covenant, or duty on the
                  part of INTERCHEM under this Agreement;

         9.3.2.   any negligence or willful misconduct of INTERCHEM or their
                  respective employees, officers or directors in performing this
                  Agreement.

9.4.     The foregoing indemnification obligations are subject to the following:
                ***
                                                 ***
                                                 ***
                                                 ***
                              ***

9.5.     The indemnification rights provided for herein are in addition to, and
         not in substitution for, any and all remedies available to a Party
         under this Agreement or otherwise at law or in equity. Notwithstanding
         anything to the contrary in this Section 9, each Party may, and
         expressly reserves the right to, seek judicial relief from any court of
         competent jurisdiction in order to obtain an injunction or other
         equitable relief.

9.6.     IN NO EVENT SHALL ANY OF THE PARTIES HERETO BE RESPONSIBLE OR LIABLE TO
         THE OTHER UNDER ANY PROVISION OF THIS AGREEMENT OR UNDER ANY THEORY OF
         NEGLIGENCE, STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY, FOR
         ANY CONSEQUENTIAL, INDIRECT, SPECIAL, OR EXEMPLARY DAMAGES OR LOST
         PROFITS. FOR THE PURPOSE OF CLARITY, NOTHING IN THIS SECTION IS
         INTENDED TO LIMIT THE INDEMNIFICATION OBLIGATIONS OF ANY PARTY WITH
         RESPECT TO THE

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                                       15

<PAGE>

         CHARACTERIZATION OF ANY CLAIM BY A THIRD PARTY AS CONSEQUENTIAL,
         INDIRECT, SPECIAL, OR EXEMPLARY DAMAGES OR LOST PROFITS.

10.      COSTS AND EXPENSES OF RECALL

10.1.    SANTARUS shall have sole control and responsibility for conducting all
         voluntary and involuntary recalls or other related action
         (collectively, "RECALLS") of units of any Finished Product; provided,
         however, that UQUIFA agrees to reimburse SANTARUS for all of its
         reasonable costs and expenses incurred with respect to any Recalls
         arising out of any of the causes set forth in Sections 9.2.1 through
         9.2.4. This Section 10 is intended to augment and not limit the
         indemnification provisions of Section 9 herein.

11.      TERM AND TERMINATION.

11.1.    This Agreement shall be effective for a period of four (4) years from
         the Effective Date hereof (the "INITIAL TERM") and shall be
         automatically renewed for additional two (2) year terms unless written
         notice of intent to terminate is provided by SANTARUS at least twelve
         (12) months prior to the expiration of the Initial Term or any
         extension term.

11.2.    This Agreement may be terminated by (i) SANTARUS upon      ***     days
         written notice to INTERCHEM or UQUIFA, as the case may be, of a failure
         by INTERCHEM or UQUIFA to perform or observe any material covenant,
         condition or agreement to be performed or observed by it under this
         Agreement, unless such breach has been cured within the   ***   notice
         period and (ii) UQUIFA upon    ***    written notice to SANTARUS of a
         failure by SANTARUS to perform or observe any material covenant,
         condition or agreement to be performed or observed by it under this
         Agreement, unless such breach has been cured within the   ***   notice
         period; provided, however, that with respect to a failure to timely
         supply ordered quantities of Omeprazole under this Agreement, UQUIFA
         and INTERCHEM combined shall have the right to cure such breach    ***
         during the term of this Agreement unless otherwise agreed by SANTARUS
         in writing; and provided, further, that if the breach by SANTARUS is a
         failure to pay an invoice when due (except as provided in Section 5.5),
         then the notice and cure period shall be       ***

11.3.    SANTARUS may terminate this Agreement effective immediately upon
         written notice to UQUIFA and INTERCHEM in the event that (a) UQUIFA or
         INTERCHEM dissolves, is declared insolvent or bankrupt by a court of
         competent jurisdiction; (b) a voluntary or involuntary petition of
         bankruptcy is filed in any court of competent jurisdiction by UQUIFA or
         INTERCHEM; or (c) this Agreement is assigned by UQUIFA or INTERCHEM for
         the benefit of creditors. UQUIFA or INTERCHEM may terminate this
         Agreement effective immediately upon written notice to SANTARUS in the
         event that (a) SANTARUS dissolves, is declared insolvent or bankrupt by
         a court of competent jurisdiction; (b) a voluntary or involuntary
         petition of bankruptcy is filed in any court of competent jurisdiction
         by SANTARUS; or (c) this Agreement is assigned by SANTARUS for the
         benefit of creditors.

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                                       16

<PAGE>

11.4.    SANTARUS may terminate this Agreement upon     ***     prior written
         notice to INTERCHEM and UQUIFA (or a shorter period required by the
         agency with jurisdiction) in the event that any governmental agency
         takes any action, or raises any objection, that prevents SANTARUS from
         importing, exporting, purchasing or selling either the Omeprazole or
         the Finished Product for a period reasonably anticipated to endure for
         more than      ***

11.5.    In the event of termination of this Agreement by SANTARUS due to an
         uncured breach of this Agreement by INTERCHEM or for INTERCHEM's
         dissolution, insolvency or bankruptcy pursuant to Section 11.3, UQUIFA
         will supply Omeprazole directly to SANTARUS, at SANTARUS' election,
         under terms of an agreement no less favorable to SANTARUS than the
         terms herein.

11.6.    SANTARUS may terminate this Agreement effective immediately upon
         written notice to INTERCHEM and UQUIFA should any legal proceeding be
         instituted against INTERCHEM or UQUIFA, which is reasonably likely to
         materially adversely impact INTERCHEM's and/or UQUIFA's ability to
         properly perform under this Agreement or subject SANTARUS to any
         material risk of liability or loss.

11.7.    In the event of termination of this Agreement by SANTARUS pursuant to
         Section 11.4, SANTARUS                ***
                                               ***
                                               ***
                                               ***
                        ***

11.8.    The provisions of this Section 11 as to termination shall not limit or
         restrict the rights of any Party to seek remedies or take measures that
         may be otherwise available to it at law or equity in connection with
         the enforcement and performance of obligations under this Agreement.

12.      NOTICES

Any and all notices required to be given under this Agreement will be in writing
and effective upon receipt, sent by facsimile transmission, mailed postage
prepaid by first-class certified or registered mail, or sent by express courier
service, at the respective addresses, as follows:

IF TO SANTARUS, TO:

         Santarus, Inc.
         10590 W. Ocean Air Drive
         Suite 200
         San Diego, CA 92130
         Attention: Vice President, Manufacturing
         and Product Development
         Telephone Number: (858) 314-5700

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                                       17

<PAGE>

         Facsimile Number:  (858) 314-5701

With a copy to:

         Santarus, Inc.
         10590 W. Ocean Air Drive
         Suite 200
         San Diego, CA 92130
         Attention: Sr. Dir., Legal Affairs
         Telephone Number: (858) 314-5700
         Facsimile Number: (858) 314-5702

IF TO INTERCHEM, TO:

         Interchem Trading Corporation
         120 Route 17 North
         P.O. Box 1579
         Paramus, NJ 07653
         Attention: Joseph M. Pizza
         Telephone Number: 201-261-7333
         Facsimile Number: 201-261-7339

IF TO UQUIFA, TO:

         Union Quimico Farmaceutica, SA
         Mallorca, 262
         08008 Barcelona, Spain
         Attention: Mark I. Robbins, Chief Executive
         Telephone Number: 011-34-93-467-48-10
         Facsimile Number: 011-34-93-488-04-91

With a copy to:

         Union Quimico Farmaceutica, SA
         Mallorca, 262
         08008 Barcelona, Spain
         Attention: Legal Affairs
         Telephone Number: 011-34-93-467-48-10
         Facsimile Number: 011-34-93-488-04-91

13.      MISCELLANEOUS

13.1.    Force Majeure. In the event that any Party hereto is prevented from
         complying, either in whole or in part, with any of the terms or
         provisions of this Agreement by reason of fire, flood, storm, strike or
         lockout, riot, war, rebellion, lack or failure of transportation


                                       18

<PAGE>

         facilities, court order, accident, or Acts of God, and to the extent
         that the foregoing are beyond a Party's reasonable control, then,
         unless conclusive evidence to the contrary is provided, upon written
         notice by the Party whose performance is so affected to the other, the
         requirements of this Agreement so affected (to the extent affected)
         shall be suspended during the period of, and only to the extent of,
         such disability. Said Party shall be excused by reason of said force
         majeure only so long as it is exercising its best efforts to overcome
         said reason.

13.2.    Assurances. Each Party to this Agreement shall execute, acknowledge and
         deliver such further instruments and documents, and do all such other
         acts and things as may be required by law or as may be necessary or
         advisable to carry out the intents and purposes of this Agreement. The
         Parties will cooperate with each other and offer reasonable assistance
         in carrying out their respective responsibilities under this Agreement.

13.3.    Compliance with Laws. Each Party will comply with all applicable laws,
         rules and regulations in the conduct of its responsibilities and
         activities under this Agreement.

13.4.    Governing Law. This Agreement shall be construed in accordance with the
         internal laws of the State of *** without reference to the conflict of
         laws provisions thereof. Each of the Parties hereto consents and agrees
         to the exclusive jurisdiction and venue of the state and federal courts
         sitting within the State of *** in connection with any legal
         proceedings brought by any other part relating to the subject matter of
         this Agreement and further agrees and consents that any resulting
         judgment rendered by any such court against a Party shall be valid and
         binding on such Party and may be entered in any jurisdiction in which
         such Party is located.

13.5.    Severability. If any provision of this Agreement shall be held to be
         invalid, illegal, or unenforceable, the validity, legality, or
         enforceability of the remaining provisions hereof shall not in any way
         be affected or impaired thereby unless the purposes of the Agreement
         cannot be achieved. In the event any provision shall be held invalid,
         illegal, or unenforceable the Parties shall use best efforts to
         substitute a valid, legal, and enforceable provision which insofar as
         practical implements the purposes hereof.

13.6.    No Assignment. No Party shall assign its rights and/or obligations
         under this Agreement without the prior written consent of the other
         Parties hereto, except that (a) SANTARUS may assign this Agreement in
         connection with the transfer or sale of all or substantially all of its
         assets or business to which the subject matter of this Agreement
         relates or in connection with any merger, consolidation or
         reorganization, without UQUIFA's or INTERCHEM's prior written consent;
         and (b) UQUIFA and/or INTERCHEM may assign this Agreement in connection
         with the transfer or sale of all or substantially all of its assets or
         business to which the subject matter of this Agreement relates or in
         connection with any merger, consolidation or reorganization with
         SANTARUS's prior written consent, which consent may not be unreasonably
         withheld.

13.7.    Waiver. No delay, waiver, omission or forbearance on the part of any
         Party to exercise any right, option, duty or power arising out of any
         breach or default by any other Party of any of the terms, provisions or
         covenants hereof, will constitute a waiver by such Party of

                                       19

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<PAGE>

         its rights to enforce any such right, option, duties or power as
         against the other Party hereto, or its rights as to any subsequent
         breach or default by the other Party.

13.8.    Survival. Upon termination or expiration of this Agreement, the
         obligations of the Parties which by their nature should survive and the
         obligations under Sections 7-13 of this Agreement and under any
         existing confidentiality agreements between the Parties shall survive.

13.9.    Entire Agreement. This Agreement and the Schedules attached hereto and
         the confidentiality agreements referenced in Section 13.8 constitute
         the full understanding and entire agreement between the Parties and
         supersede any and all prior oral or written understandings and
         agreements with respect to the subject matter hereof. No terms,
         conditions, understandings, or agreements purporting to modify, amend,
         waive or terminate this Agreement, or any provision hereof, shall be
         binding except by the execution of a writing specified to be an
         explicit amendment to this Agreement duly executed by the authorized
         signatories of the Parties hereto. No modification, waiver,
         termination, rescission, discharge or cancellation of any right or
         claim under this Agreement shall affect the right of any Party to
         enforce any other claim or right hereunder.

13.10.   Binding Agreement. Subject to Section 13.6, this Agreement shall be
         binding upon the Parties and their respective successors and permitted
         assigns and shall insure to the benefit of the Parties and their
         respective successors and permitted assigns.

13.11.   Headings. The headings used in this Agreement are for convenience of
         reference only and are not a part of the text hereof.

13.12.   Counterparts. This Agreement may be executed in counterparts, each of
         which shall constitute an original and all of which shall together
         constitute a single agreement.

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                                       20

<PAGE>

IN WITNESS WHEREOF, the Parties hereby agree to the terms and conditions of this
Agreement.

SANTARUS, INC.                               INTERCHEM TRADING
                                             CORPORATION d/b/a INTERCHEM
                                             CORPORATION

By:          /s/ Gerald T. Proehl            By:       /s/ Joseph M. Pizza
   ---------------------------------------      --------------------------------
Name:        Gerald T. Proehl                Name:     Joseph M. Pizza
Title:       President & CEO                 Title:    President
Date:         10/13/03                       Date:     9/29/2003

UNION QUIMICO FARMACEUTICA,
   S.A.

By:        /s/ Mark Ian Robbins
   ---------------------------------
Name:      Mark Ian Robbins
Title:     Chief Executive
Date:       6.10.2002

                 [SIGNATURE PAGE TO OMEPRAZOLE SUPPLY AGREEMENT]

<PAGE>

                                   SCHEDULE A

                                 SPECIFICATIONS

                                       ***
                                       ***
                                       ***

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<PAGE>

                                   SCHEDULE B

                                    LEAD TIME

                                       ***
                                       ***
                                       ***

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<PAGE>

                                   SCHEDULE C

                           PRICING AND SHIPPING TERMS

FREIGHT TERMS: INTERCHEM and UQUIFA shall make all necessary shipping
arrangements to SANTARUS' designated facility,          ***       SANTARUS'
designated facility, freight prepaid.

SHIPPING METHOD: Air Freight

PRICE:

                                       ***
                                       ***
                                       ***

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<PAGE>

                                   APPENDIX A

                             FORM OF PURCHASE ORDER

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