MOLECULAR BIOSYSTEMS INC
8-K, 1998-04-22
IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES
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<PAGE>

                          SECURITIES AND EXCHANGE COMMISSION
                                           
                                Washington, D.C. 20549
                                           
                                           
                                   _______________
                                           
                                           
                                       FORM 8-K
                                           
                                    CURRENT REPORT
                                           
                                           
                        PURSUANT TO SECTION 13 OR 15(d) OF THE
                                           
                           SECURITIES EXCHANGE ACT OF 1934


Date of Report (Date of earliest event reported)        APRIL 7, 1998
                                                 ------------------------------

                              MOLECULAR BIOSYSTEMS, INC.
                  --------------------------------------------------
                  (Exact name of registrant as specified in charter)



        DELAWARE                       1-10546                  38-30878632 
- ----------------------------         ------------           -------------------
(State or other jurisdiction         (Commission              (IRS Employer  
     of incorporation)               File Number)           Identification No.)


10070 BARNES CANYON ROAD, SAN DIEGO, CALIFORNIA                     92121   
- -----------------------------------------------                  ----------
   (Address of principal executive offices)                      (Zip Code)



Registrant's telephone number, including area code     (619) 452-0681         
                                                   ----------------------------

                10030 BARNES CANYON ROAD, SAN DIEGO, CALIFORNIA 92121          
            --------------------------------------------------------------
            (Former name or former address, if changed since last report.)


<PAGE>

ITEM 2.        ACQUISITION OR DISPOSITION OF ASSETS.

     On April 7, 1998, Molecular Biosystems, Inc. (the "Company") granted an 
exclusive license to Chugai Pharmaceutical Co., Ltd. ("Chugai") in Japan, 
Taiwan and South Korea for certain products pursuant to a Cooperative 
Development and Marketing Agreement.  The Company also sold shares of its 
common stock to Chugai pursuant to a Common Stock Purchase Agreement as part 
of the transaction.  Both of those Agreements are filed as exhibits to this 
Current Report on Form 8-K.

     COOPERATIVE DEVELOPMENT AND MARKETING AGREEMENT.

     Under the Cooperative Development and Marketing Agreement (the 
"Development Agreement"), the Company granted Chugai an exclusive license for 
the development and sale of Company products in Japan, Taiwan and South 
Korea.  This license will allow Chugai to develop and sell FS069, 
ORALEX-Registered Trademark- and a potential future ultrasound product for 
fifteen years from March 31, 1998.  The Company also granted to Chugai a 
right of first offer with respect to all ultrasound imaging agents owned or 
developed by the Company for certain uses in Japan, Taiwan and South Korea.  
FS069 is a perfluorocarbon based cardiac ultrasound contrast imaging agent.  
ORALEX-Registered Trademark- is a proprietary oral ultrasound agent to be 
used in the examination of the upper gastrointestinal anatomy.  

     Under the Development Agreement, the Company will receive from Chugai an 
initial license fee of $14 million, milestone payments of up to $20 million 
based on the achievement of certain product development goals and royalty 
payments from Chugai based on the sale of commercialized products in Japan, 
Taiwan and South Korea.  There can be no assurance, however, that all or any 
of these product development goals will be satisfied or that any products 
will be commercialized.

     COMMON STOCK PURCHASE AGREEMENT.

     Under the Common Stock Purchase Agreement, the Company sold to Chugai 
691,883 shares of common stock for $12.00 per share for a total equity 
investment of $8.3 million.  These shares are subject to certain covenants 
and restrictions, including "standstill" rights of the Company, a market 
stand-off provision and restrictions on transferability.

ITEM 7.        FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND
               EXHIBITS.

          (a)  Financial Statements:  Not applicable.

          (b)  PRO FORMA Financial Information:  Not Applicable

          (c)  Exhibits

          The following Exhibits are hereby filed as part of this Current 
Report on Form 8-K.

<TABLE>
<CAPTION>

EXHIBIT   DESCRIPTION

<S>      <C>
 2.1      Cooperative Development and Marketing Agreement effective as of March
          31, 1998 between the Company and Chugai Pharmaceutical Co., Ltd.

 2.2      Common Stock Purchase Agreement effective as of March 31, 1998 between
          the Company and Chugai Pharmaceutical Co., Ltd.

99.1      Press Release issued on April 8, 1998.

</TABLE>

                                       -2-

<PAGE>

                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the 
registrant has duly caused this report to be signed on its behalf by the 
undersigned hereunto duly authorized.

                                   MOLECULAR BIOSYSTEMS, INC.



                                   By:  /s/ Gerard A. Wills                    
                                       ----------------------------------------
                                        Gerard A. Wills
                                        Vice President, Finance and
                                        Chief Financial Officer


Date: April 22, 1998


                                       -3-

<PAGE>

                                 EXHIBIT INDEX

The following Exhibits are filed herewith:

<TABLE>
<CAPTION>

EXHIBIT   DESCRIPTION
<S>      <C>
+2.1      Cooperative Development and Marketing Agreement effective as of March
          31, 1998 between the Company and Chugai Pharmaceutical Co., Ltd.

 2.2      Common Stock Purchase Agreement effective as of March 31, 1998 between
          the Company and Chugai Pharmaceutical Co., Ltd.

99.1      Press Release issued April 8, 1998.

</TABLE>

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

           +   Certain confidential portions of this Exhibit were omitted by
               means of marking such portions with an asterisk (the "Mark"). 
               This Exhibit has been filed separately with the Secretary of the
               Commission without the Mark pursuant to the Company's Application
               Requesting Confidential Treatment under Rule 24b-2 under the
               Exchange Act of 1934, as amended.


                                       -4-

<PAGE>

                                                                    EXHIBIT 2.1
















                   COOPERATIVE DEVELOPMENT AND MARKETING AGREEMENT




















***  Certain confidential portions of this Exhibit were omitted by means of
     blackout of the text (the "Mark").  This Exhibit has been filed separately
     with the Secretary of the Commission without the Mark pursuant to the
     Company's Application Requesting Confidential Treatment under Rule 24b-2
     under the 1934 Act.  

                                      -1-

<PAGE>

                                  TABLE OF CONTENTS

                                                                           Page


ARTICLE 1 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .  1

ARTICLE 2 GRANT OF RIGHTS. . . . . . . . . . . . . . . . . . . . . . . . . .  7
     2.1  License Grants.. . . . . . . . . . . . . . . . . . . . . . . . . .  7
          (a)  Licensed Products.. . . . . . . . . . . . . . . . . . . . . .  7
          (b)  Chugai Improvements, Patents and Technology . . . . . . . . .  8
     2.2  Additional Imaging Products. . . . . . . . . . . . . . . . . . . .  8
     2.3  Covenant Not to Market or Sell Competitive Products. . . . . . . .  9

ARTICLE 3 DEVELOPMENT OF LICENSED PRODUCTS . . . . . . . . . . . . . . . . .  9
     3.1  Executive Committee. . . . . . . . . . . . . . . . . . . . . . . .  9
     3.2  Task Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     3.3  Chugai Development Efforts . . . . . . . . . . . . . . . . . . . . 10
     3.4  Filing for Marketing Approval for FS069. . . . . . . . . . . . . . 11
     3.5  Discontinuance of Chugai's Development Efforts . . . . . . . . . . 11
     3.6  MBI's Development Efforts. . . . . . . . . . . . . . . . . . . . . 12
     3.7  Coordination Among Licensees . . . . . . . . . . . . . . . . . . . 12
     3.8  Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

ARTICLE 4 COMMERCIALIZATION. . . . . . . . . . . . . . . . . . . . . . . . . 13
     4.1  Product Launch . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     4.2  Promotion and Marketing Obligations. . . . . . . . . . . . . . . . 13
          (a)  Marketing Efforts . . . . . . . . . . . . . . . . . . . . . . 13
          (b)  General Conduct . . . . . . . . . . . . . . . . . . . . . . . 14
          (c)  Trademark(s). . . . . . . . . . . . . . . . . . . . . . . . . 14
          (d)  Sales Forecasts . . . . . . . . . . . . . . . . . . . . . . . 14
          (e)  Phase IV Surveillance; Marketing Trials . . . . . . . . . . . 14

ARTICLE 5 ROYALTY AND MILESTONE PAYMENTS TO MBI. . . . . . . . . . . . . . . 15
     5.1  License Fee. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
     5.2  Milestone Payments . . . . . . . . . . . . . . . . . . . . . . . . 15
     5.3  Earned Royalties . . . . . . . . . . . . . . . . . . . . . . . . . 16
     5.4  Purchase Price for Licensed Products . . . . . . . . . . . . . . . 17
     5.5  Annual Minimum Royalties       ***     . . . . . . . . . . . . . . 17
     5.6  Funding of MBI Development Costs . . . . . . . . . . . . . . . . . 18
     5.7  Repayment of MBI Development Costs; Use of Chugai Data . . . . . . 18
     5.8  Records and Audit. . . . . . . . . . . . . . . . . . . . . . . . . 19

ARTICLE 6 PROCEDURE FOR PAYMENTS; RECORDS; AUDIT . . . . . . . . . . . . . . 19
     6.1  Manner and Place of Payment. . . . . . . . . . . . . . . . . . . . 19

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

                                      -i-

<PAGE>

     6.2  Records and Audit. . . . . . . . . . . . . . . . . . . . . . . . . 20


















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

                                     -ii-

<PAGE>

     6.3  Withholding Taxes. . . . . . . . . . . . . . . . . . . . . . . . . 20
     6.4  Product Bundling . . . . . . . . . . . . . . . . . . . . . . . . . 20

ARTICLE 7 MANUFACTURE AND SUPPLY OF LICENSED PRODUCTS. . . . . . . . . . . . 21
     7.1  Manufacture and Supply of Licensed Products. . . . . . . . . . . . 21
     7.2  Orders for Clinical Supplies . . . . . . . . . . . . . . . . . . . 22
     7.3  Delivery of Clinical Supplies. . . . . . . . . . . . . . . . . . . 22
     7.4  NO WARRANTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

ARTICLE 8 MARKETING AUTHORIZATIONS; OTHER REGULATORY COMPLIANCE ISSUES . . . 22
     8.1  Supply of Data . . . . . . . . . . . . . . . . . . . . . . . . . . 22
     8.2  Obtaining Marketing Authorizations . . . . . . . . . . . . . . . . 23
     8.3  Marketing Authorization Holder . . . . . . . . . . . . . . . . . . 23
     8.4  Marketing Authorizations and Pre-Marketing Expenses. . . . . . . . 23
     8.5  Provision of Regulatory Filings. . . . . . . . . . . . . . . . . . 23
     8.6  Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
     8.7  Adverse Reaction Reporting . . . . . . . . . . . . . . . . . . . . 23
     8.8  Post-First Commercial Sale Testing and Reporting . . . . . . . . . 24
     8.9  Product Recall . . . . . . . . . . . . . . . . . . . . . . . . . . 24
     8.10 Reports. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

ARTICLE 9 CONFIDENTIALITY. . . . . . . . . . . . . . . . . . . . . . . . . . 25
     9.1  Nondisclosure Obligations. . . . . . . . . . . . . . . . . . . . . 25
     9.2  Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
     9.3  Authorized Disclosure. . . . . . . . . . . . . . . . . . . . . . . 25
     9.4  Injunctive Relief. . . . . . . . . . . . . . . . . . . . . . . . . 26

ARTICLE 10 INTELLECTUAL PROPERTY . . . . . . . . . . . . . . . . . . . . . . 26
     10.1 Ownership of Intellectual Property . . . . . . . . . . . . . . . . 26
     10.2 Validity and Infringement of MBI Patents and Chugai Patents. . . . 26
     10.3 Infringement of Third Party Patents. . . . . . . . . . . . . . . . 27
     
     10.4 Responsibility for Patents and Trademarks . . . . . . . . . . . . .29

ARTICLE 11 TERM AND TERMINATION OF AGREEMENT . . . . . . . . . . . . . . . . 30
     11.1 Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
     11.2 Effect of Failure to Conduct Obligations . . . . . . . . . . . . . 30
     11.3 Termination for Default. . . . . . . . . . . . . . . . . . . . . . 32
     11.4 Effect of Termination. . . . . . . . . . . . . . . . . . . . . . . 32
          (a)  Termination by MBI. . . . . . . . . . . . . . . . . . . . . . 32
          (b)  Termination by Chugai . . . . . . . . . . . . . . . . . . . . 33
          (c)  Discontinuance of Development by Chugai . . . . . . . . . . . 34
     11.5 Surviving Obligations. . . . . . . . . . . . . . . . . . . . . . . 35

                                     -iii-

<PAGE>

ARTICLE 12 INDEMNITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
     12.1 Indemnification by MBI . . . . . . . . . . . . . . . . . . . . . . 35
     12.2 Indemnification by Chugai. . . . . . . . . . . . . . . . . . . . . 35
     12.3 Indemnification Procedures . . . . . . . . . . . . . . . . . . . . 35
     12.4 Exclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
     12.5 LIMITED LIABILITY. . . . . . . . . . . . . . . . . . . . . . . . . 36

ARTICLE 13 REPRESENTATIONS AND WARRANTIES. . . . . . . . . . . . . . . . . . 36
     13.1 Representation and Warranties of MBI . . . . . . . . . . . . . . . 36
          (a)  Corporate Power . . . . . . . . . . . . . . . . . . . . . . . 36
          (b)  Due Authorization . . . . . . . . . . . . . . . . . . . . . . 36
          (c)  Binding Agreement . . . . . . . . . . . . . . . . . . . . . . 36
          (d)  Documents Filed with FDA. . . . . . . . . . . . . . . . . . . 36
     13.2 Representations and Warranties of Chugai . . . . . . . . . . . . . 37
          (a)  Corporate Power . . . . . . . . . . . . . . . . . . . . . . . 37
          (b)  Due Authorization . . . . . . . . . . . . . . . . . . . . . . 37
          (c)  Binding Agreement . . . . . . . . . . . . . . . . . . . . . . 37
          (d)  No Transfers of Marketing Authorizations. . . . . . . . . . . 37
     13.3 WARRANTY DISCLAIMER. . . . . . . . . . . . . . . . . . . . . . . . 37

ARTICLE 14 ASSIGNMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
     14.1 Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
     14.2 Benefits and Binding Nature of Agreement . . . . . . . . . . . . . 37
     14.3 Prohibited Assignment Null and Void. . . . . . . . . . . . . . . . 38

ARTICLE 15 DISPUTE RESOLUTION. . . . . . . . . . . . . . . . . . . . . . . . 38
     15.1 Arbitration. . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
     15.2 Injunctive Relief. . . . . . . . . . . . . . . . . . . . . . . . . 38

ARTICLE 16 MISCELLANEOUS . . . . . . . . . . . . . . . . . . . . . . . . . . 39
     16.1  Export Law Compliance. . . . . . . . . . . . . . . . . . . . . . .39
     16.2  Foreign Corrupt Practices Act. . . . . . . . . . . . . . . . . . .39
     16.3  Entire Agreement . . . . . . . . . . . . . . . . . . . . . . . . .39
     16.4  Amendments and Waivers . . . . . . . . . . . . . . . . . . . . . .39
     16.5  No Other Terms and Conditions. . . . . . . . . . . . . . . . . . .39
     16.6  Force Majeure. . . . . . . . . . . . . . . . . . . . . . . . . . .40
     16.7  Notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
     16.8  English Language; Governing Law. . . . . . . . . . . . . . . . . .40
     16.9  Late Payments. . . . . . . . . . . . . . . . . . . . . . . . . . .41
     16.10 Severability. . . . . . . . . . . . . . . . . . . . . . . . . . . 41
     16.11 Rights and Remedies Cumulative. . . . . . . . . . . . . . . . . . 41
     16.12 Independent Contractors . . . . . . . . . . . . . . . . . . . . . 41
     16.13 Captions and Section References . . . . . . . . . . . . . . . . . 41
     16.14 References to Dollars . . . . . . . . . . . . . . . . . . . . . . 41
     16.15 Counterparts. . . . . . . . . . . . . . . . . . . . . . . . . . . 41
     16.16 Press Releases. . . .. . . . . . . . . . . . . . . . . . . . . . .41

                                     -iv-

<PAGE>
                             SCHEDULE OF EXHIBITS

     EXHIBIT        DESCRIPTION

     Exhibit 1.23   FS069
     Exhibit 1.34   MBI Patents
     Exhibit 1.40   ORALEX -Registered Trademark
     Exhibit 1.45   ***
     Exhibit 3.6(a) ORALEX -Registered Trademark and FS069
                     Development Program


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

                                      -v-

<PAGE>

                COOPERATIVE DEVELOPMENT AND MARKETING AGREEMENT


     THIS COOPERATIVE DEVELOPMENT AND MARKETING AGREEMENT (the "Agreement") is
made effective as of March 31, 1998 (the "Effective Date"), by and between
MOLECULAR BIOSYSTEMS, INC., a Delaware corporation ("MBI"), having a principal
place of business at 10030 Barnes Canyon Road, San Diego, CA 92121-2789, USA,
and CHUGAI PHARMACEUTICAL CO., LTD., a Japanese corporation ("Chugai"), having a
principal place of business at 2-1-9, Kyobashi, Chuo-ku, Tokyo 104-8301, Japan.

                                   RECITALS

     A.   MBI is engaged in the business of developing and commercializing
contrast agents for ultrasound and computed tomography.

     B.   Chugai desires to develop and commercialize certain of those 
ultrasound contrast agents, specifically FS069,  ***  and ORALEX-Registered 
Trademark- (as defined below), in the Territory (as defined below), and to 
purchase $8.3 million of MBI Common Stock pursuant to the Common Stock 
Purchase Agreement between the parties and dated as of the date hereof.

     C.   MBI and Chugai now desire that MBI grants to Chugai certain rights and
Chugai undertakes certain obligations relating to the contrast agents in the
Territory on the terms and conditions set forth herein.

     NOW THEREFORE, in consideration of the foregoing premises and the covenants
set forth below, the parties hereby agree as follows:

                                  ARTICLE 1
                                 DEFINITIONS

     As used herein, the following terms shall have the following meanings:

1.1  "ADDITIONAL IMAGING PRODUCTS" shall mean any ultrasound imaging agent owned
and developed by MBI during the Term, but only to the extent of its application
in the Field, other than a Licensed Product.  Notwithstanding the foregoing,
Additional Imaging Products shall not include any products that MBI does not
have the right to license to Chugai because of any patent, trademark or other
intellectual property rights of Third Parties.

1.2  "AFFILIATE" shall mean, with respect to each party, any entity directly or
indirectly controlling, controlled by or under common control with that party
where control means the ownership or control, directly or indirectly, of more
than fifty percent (50%) of all of the voting power of the shares (or other
securities or rights) entitled to vote for the election of directors or other
governing authority, as of the date of this Agreement or hereafter during the
Term; provided that such entity shall be considered an Affiliate only for the
time during which such control exists.

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

                                      -1-

<PAGE>

1.3  "APPLICABLE LAWS" shall mean all applicable laws, rules, regulations and 
guidelines within or without the Territory that may apply to the development, 
manufacturing, marketing or sale of the Licensed Products in the Territory or 
the performance of either party's obligations under this Agreement, including 
laws, regulations and guidelines governing the import, export, development, 
manufacture, marketing, distribution and sale of the Licensed Products in the 
Territory and the United States, to the extent applicable, and including all 
Good Manufacturing Practices or Good Clinical Practices standards or 
guidelines promulgated by the FDA or the Competent Authorities and including 
trade association guidelines, where applicable, as well as U.S. export 
control laws and the U.S. Foreign Corrupt Practices Act ("FCPA").

1.4  "CALENDAR QUARTER" shall mean a quarter ending on March 31, June 30, 
September 30 or December 31 of each Fiscal Year.

1.5  "CHANGE IN CONTROL" shall mean, with respect to each party, (i) a merger or
consolidation in which the party is not the surviving corporation or company; or
(ii) any transaction in which any "person" (within the meaning of Section 13(d)
and Section 14(d)(2) of the Securities Exchange Act 1934) is or becomes the
beneficial owner, directly or indirectly, of securities of the party
representing 50% plus one vote or more of the combined voting power of such
party's then-outstanding securities; or (iii) a sale of substantially all of the
party's assets.

1.6  "CHUGAI DEVELOPMENT PROGRAM" shall mean the preclinical, clinical and
process development programs to be conducted by Chugai in the Territory for each
of the Licensed Products.

1.7  "CHUGAI IMPROVEMENTS" shall mean any improvement or modification of or
relating to the MBI Technology, the Chugai Technology, the MBI Patents, the
Chugai Patents or the MBI Improvements made during the Term by either (i) Chugai
or any of its Affiliates or (ii) a Third Party for Chugai or any of its
Affiliates (to the extent that Chugai or its Affiliates have rights to
sublicense to MBI such improvement or modification or related technology).

1.8  "CHUGAI PATENTS" shall mean all patents (including, without limitation, all
substitutions, extensions, reissues, renewals, reexaminations, patents of
addition, supplementary protection certificates and inventors' certificates
thereof) and all patent applications (including, without limitation, all
provisional applications, divisions, continuations and continuations-in-part)
owned or in-licensed (with a right to sublicense) by Chugai or any of its
Affiliates during the Term that contain claims that are based upon or relate to
any of the Chugai Technology or the Chugai Improvements.

1.9  "CHUGAI TECHNOLOGY" shall mean, to the extent owned or in-licensed (with a
right to sublicense) by Chugai during the Term and necessary or useful to
develop, manufacture, use, sell or distribute the Licensed Products, the
following: all technology, technical information, inventions (whether or not
patentable), know-how, procedures, methods, designs and data, including, without
limitation, concepts, discoveries, works of expression, derivative works,
specifications, processes, techniques, plans, drawings, and all other scientific
or technical information or materials, in whatever form, and all patent,
copyright, trademark and trade secret rights.

                                      -2-

<PAGE>

1.10 "COMMENCEMENT" shall mean, with respect to a clinical trial, the date 
upon which the first patient is enrolled in the clinical trial.

1.11 "COMPETENT AUTHORITIES" shall mean the governmental entities in the
Territory responsible for the regulation of the Licensed Products, including,
without limitation, the MHW.

1.12 "COMPETITIVE PRODUCTS" shall mean any product intended for use or used in
connection with the Field other than any Licensed Product and any Additional
Imaging Product to which Chugai obtains rights under Section 2.2.  

1.13 "CONFIDENTIAL INFORMATION" shall mean, subject to the exceptions set forth
in Section 9.2, any information received by one party from the other party
pertaining to the MBI Technology, Chugai Technology, MBI Patents, Chugai Patents
or the Improvements, any know-how, data, process, technique, or formula relating
to the Licensed Products, or the Improvements, any research project or work in
process, and any development, scientific, engineering, manufacturing, marketing,
business, financial or personnel matter relating to either party, its present or
future products, sales, suppliers, customers, employees, investors or business,
whether in oral, written, graphic or electronic form.

1.14 "END USER" shall mean the entity that purchases a Licensed Product for use
for its intended purpose and not for resale or other redistribution.

1.15 "EUROPEAN COUNTRIES" shall mean all member countries of the European Union.

1.16 "EXECUTIVE COMMITTEE" shall mean the committee established pursuant to
Section 3.1.

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

1.18 "FD&C ACT" shall mean the United States Federal Food, Drug and Cosmetic Act
and applicable regulations promulgated thereunder, as amended from time to time.

1.19 "FIELD" shall mean any  *** .

1.20 "FIRST COMMERCIAL SALE" shall mean, (i) with respect to each country in the
Territory, the first sale in or into such country by Chugai, one of its
Affiliates or sublicensees, or one of its or their distributors after receipt of
Marketing Authorization of any Licensed Product to any end user for commercial
use, and (ii) with respect to the Territory, the first sale in the Territory by
Chugai, one of its Affiliates or sublicensees, or one of its or their
distributors after receipt of Marketing Authorization of any Licensed Product to
any end user for commercial use.  

1.21 "FISCAL YEAR" shall mean the period from April 1 through March 31.

1.22 "FORCE MAJEURE" shall mean any act or occurrence beyond the reasonable
control of a party that prevents its performance of any covenant or obligation
under this Agreement including

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without limitation:  (i) lightning, storms, earthquakes, landslides, flood, 
washouts or other acts of God; (ii) fires, explosions or breakage of or 
accidents to plant, machinery, equipment or storage; (iii) shortage of 
necessary labor, strikes, lockouts or other labor disturbances that could not 
reasonably have been foreseen or, even if reasonably foreseeable, could not 
have been avoided through reasonable efforts; (iv) civil disturbances, 
sabotage, war, blockades, insurrections, vandalism, riots, or epidemics; (v) 
acts of any military authority; and (vi) unavailability of utilities or 
transportation.

1.23 "FS069" shall mean that imaging contrast agent developed by MBI known as
FS069, but only in the formulation described in Exhibit 1.23, and covered by one
or more of the MBI Patents or the Chugai Patents.  FS069 includes any modified
or improved product to the extent that the product meets the specifications
described in Exhibit 1.23.

1.24 "IMPROVEMENTS" shall mean the Chugai Improvements and the MBI Improvements.

1.25 "IND" shall mean, with respect to any formulation or indication of any
Licensed Product, a proposal through which Chugai, its Affiliates or
sublicensees obtain the appropriate regulatory agency's permission to begin
testing a drug in human subjects in any country in the Territory, which proposal
is reasonably functionally equivalent to the Investigational New Drug
Application filed with the FDA for clinical testing of new drugs.

1.26 "INITIAL TARGETED INDICATIONS" shall mean (i) in the case of FS069,  *** ;
and (ii) in the case of ORALEX-Registered Trademark-,  ***.

1.27 "LICENSED PRODUCTS" shall mean ORALEX-Registered Trademark-, FS069 and ***.

1.28 "LICENSEE" shall mean any Third Party to which MBI has granted or may in
the future grant any rights to any of the Licensed Products outside the
Territory.

1.29 "  ***  " shall mean the classification of  ***  according to  ***.

1.30 "MARKETING AUTHORIZATION" shall mean all necessary or appropriate
approvals, including, without limitation, Pricing and Reimbursement Approvals,
where applicable, to put a Licensed Product on the market in a particular
country in the Territory.

1.31 "MBI DEVELOPMENT COSTS" shall mean MBI's  ***  incurred in conducting 
the MBI Development Program with respect to  ***  , including, 
without limitation, third party contract expenditures, costs of labor 
(including, without limitation, taxes, benefits and an appropriate allocation 
of supporting overhead), employee expenses, costs of materials and supplies, 
and any other  ***.

1.32 "MBI DEVELOPMENT PROGRAM" shall mean the development program for  ***  
to be conducted by MBI as proposed by MBI and approved by Chugai.


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1.33 "MBI IMPROVEMENTS" shall mean any improvement or modification of or 
relating to the MBI Technology, the Chugai Technology, the MBI Patents, the 
Chugai Patents or the Chugai Improvements made during the Term by either (i) 
MBI or (ii) a Third Party for MBI (to the extent that MBI has rights to 
sublicense to Chugai such improvement or modification or related technology).

1.34 "MBI PATENTS" shall mean the patents listed in Exhibit 1.34 attached 
hereto and made a part hereof (including, without limitation, all 
substitutions, extensions, reissues, renewals, reexaminations, patents of 
addition, supplementary protection certificates and inventors' certificates 
thereof) and all other patents (including, without limitation, all 
substitutions, extensions, reissues, renewals, reexaminations, patents of 
addition, supplementary protection certificates and inventors' certificates 
thereof) and all patent applications (including, without limitation, all 
provisional applications, divisions, continuations and continuations-in-part) 
owned or in-licensed (with a right to sublicense) by MBI during the Term that 
contain claims that are based upon or relate to any of the MBI Technology or 
the MBI Improvements.

1.35 "MBI TECHNOLOGY" shall mean, to the extent owned or in-licensed (with a 
right to sublicense) by MBI during the Term and necessary or useful to 
develop, manufacture, use, sell or distribute the Licensed Products, the 
following:  all technology, technical information, inventions (whether or not 
patentable), know-how, procedures, methods, designs and data, including, 
without limitation, concepts, discoveries, works of expression, derivative 
works, specifications, processes, techniques, plans, drawings, and all other 
scientific or technical information or materials, in whatever form, and all 
patent, copyright, trademark and trade secret rights related to the Licensed 
Products.  

1.36 "MHW" shall mean the Japanese Ministry of Health and Welfare or any
successor Japanese governmental agency with responsibility for the regulation of
Licensed Products.

1.37 "  ***  " shall mean  ***  that evaluates  ***  ***.

1.38 "NDA" shall mean, with respect to any formulation or indication of any
Licensed Product, an application for the distribution and sale of the Licensed
Product submitted to the appropriate regulatory agency in any country in the
Territory, which application is reasonably functionally equivalent to the New
Drug Application filed with the FDA for the approval of new drugs.

1.39 "NET SALES" shall mean (a) with respect to the sale or transfer of 
Licensed Product in Japan, the gross amount invoiced by Chugai or its 
Affiliates, or if Chugai or any of its Affiliates sells or transfers any 
Licensed Product to a sublicensee or distributor (which Licensed Product is 
later sold by the sublicensee or distributor for a gross invoiced amount 
greater than the gross amount invoiced by Chugai or its Affiliate to the 
sublicensee or distributor), the gross amount invoiced by the sublicensee or 
distributor, and (b) with respect to the sale or transfer of Licensed Product 
in any country other than Japan, the gross amount invoiced by Chugai's 
sublicensees or distributors, or if Chugai or its Affiliates sell or transfer 
any Licensed Product to an entity other than a sublicensee or distributor in 
any country other than Japan, the gross amount invoiced by


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Chugai or its Affiliates, less in each case to the extent applicable (i) 
trade, quantity and cash discounts actually given, in amounts customary in 
the trade, (ii) credits actually given or made on account of rejections or 
returns, (iii) consumption tax or any corresponding taxes levied on Chugai's 
sublicensees or distributors in Korea or Taiwan and (iv) rebates actually 
given and transportation and insurance charges actually paid by Chugai or an 
Affiliate on account of sales of Licensed Products by them in Japan or by 
Chugai's sublicensees or distributors on account of sales of Licensed 
Products to Third Parties in Korea and Taiwan.  Notwithstanding the foregoing 
deductions, in no event will Net Sales in any country in the Territory be 
less than  ***  in the applicable country during the Calendar Quarter prior 
to the Calendar Quarter for which Net Sales are determined (the "Minimum 
Amount"). In addition, both parties will discuss in good faith any 
adjustments to the Minimum Amount  ***  requested by Chugai after Chugai 
finishes investigating the market for each of the Licensed Products in each 
such country. With respect to each country in the Territory, if either party 
can demonstrate that the reasonable and customary aggregate deduction from 
the gross invoiced amount for the distribution of other imaging products by a 
similarly situated entity in such country is greater or less than  ***  , the 
Minimum Amount shall be adjusted to equal such reasonable and customary 
aggregate deduction subject to a limit of no more than  ***  and no less than 
  ***. The Minimum Amount shall be subject to adjustment in each country in 
the Territory not more frequently than  ***  every Fiscal Year.  Any dispute 
between the parties regarding a proposed adjustment to the Minimum Amount 
shall be resolved by arbitration conducted in accordance with the provisions 
of Section 15.1.

1.40 "ORALEX-REGISTERED TRADEMARK-" shall mean that imaging contrast agent
developed by MBI known as ORALEX-Registered Trademark-, but only in the
formulation described in Exhibit 1.40, and covered by one or more of the MBI
Patents or the Chugai Patents.  ORALEX-Registered Trademark- includes any
modified or improved product to the extent that the product meets the
specifications described in Exhibit 1.40. 

1.41 "PHASE III CLINICAL TRIAL" shall mean, with respect to a particular 
clinical trial, a large scale human clinical trial conducted by or on behalf 
of Chugai or any of its Affiliates or sublicensees, the purpose of which is 
to generate data concerning the safety and efficacy of any Licensed Product 
for the   ***  for which it is being studied to support any application for 
Marketing Authorization for the Licensed Product in any country in the 
Territory.

1.42 "PRICING AND REIMBURSEMENT APPROVALS" shall mean any pricing and 
reimbursement approvals that must be obtained before placing a Licensed 
Product on the market in any country in the Territory.

1.43 "PRODUCT UNITS" shall mean, with respect to each Licensed Product, the
individual containers that hold the Licensed Product.  MBI shall determine,
after consultation with Chugai, the size and other aspects relating to
containers for Licensed Products.

1.44 "  ***  " shall mean  ***.

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1.45 "  ***  " shall mean a   ***  , but only in the formulation described in 
Exhibit 1.45.  ***   includes any  ***   product to the extent the product 
meets the formulation described in Exhibit 1.45.

1.46 "RECORDS" shall mean complete and accurate records showing clearly all
transactions which are relevant to any sales, costs, expenses and payments under
this Agreement kept in a manner consistent with all other similar records
maintained by the party and in a manner that will facilitate a review of the
records by the other party.

1.47 "RIGHTS" shall mean the rights to develop, manufacture or sell any 
Additional Imaging Product in the Territory.

1.48 "SOP" shall mean Chugai's standard operating procedure for identifying and
reporting adverse drug experiences in compliance with Applicable Laws.

1.49 "TASK FORCE" shall mean the task force established pursuant to Section 3.2.

1.50 "TERM" shall mean the term of this Agreement as determined pursuant to
Section 11.1.

1.51 "TERRITORY" shall mean the following countries: Japan, Taiwan and South
Korea.

1.52 "THIRD PARTY" shall mean any entity or person other than MBI and its
Affiliates and Chugai and its Affiliates.

                                  ARTICLE 2
                               GRANT OF RIGHTS

2.1  LICENSE GRANTS.

     (a)  LICENSED PRODUCTS.  Subject to the terms and conditions of this
Agreement, MBI hereby grants to Chugai, and Chugai hereby accepts:  (i) an
exclusive license under the MBI Technology, the MBI Patents and the MBI
Improvements to sell and distribute Licensed Products during the Term solely
within the Territory and solely for use in the Field; (ii) an exclusive license
under the MBI Technology, the MBI Patents and the MBI Improvements to develop or
have developed the Licensed Products during the Term solely within the Territory
and solely for use in the Field and only to the extent specifically permitted
pursuant to Article 3 of this Agreement; and (iii) an exclusive license under
the MBI Technology, the MBI Patents and the MBI Improvements to make and have
made the Licensed Products during the Term solely within the Territory and
solely for use in the Field and only to the extent specifically permitted
pursuant to Article 7 of this Agreement.  Notwithstanding the foregoing grant to
Chugai of exclusive licenses to the MBI Technology, the MBI Patents and the MBI
Improvements solely within the Territory and solely for use in the Field, MBI
retains and shall have all rights to all applications of the MBI Technology, the
MBI Patents and the MBI Improvements, both outside the Territory and inside the
Territory but outside the Field.  Chugai shall have the right to sublicense the
rights granted in this Section 2.1 only

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to one or more of its Affiliates or Third Parties in the Territory, provided 
that Chugai, prior to granting any sublicense (i) gives MBI advance notice of 
the






















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sublicense and obtains MBI's prior written approval of the terms of the 
sublicense and identity of the sublicensee, which approval shall not be 
unreasonably withheld, (ii) retains control over that portion of the Chugai 
Development Program that the Affiliate or Third Party is performing, and 
(iii) remains responsible for the Affiliate's or the Third Party's compliance 
with all obligations under this Agreement.  Chugai shall cause each of its 
Affiliates, sublicensees and distributors to comply with Chugai's obligations 
under this Agreement.  MBI agrees to inform Chugai in writing, within a 
reasonable time period, of the development of any MBI Improvements, the 
issuance of any MBI Patents and the development of any MBI Technology 
licensed to Chugai pursuant to this Section 2.1(a).

     (b)  CHUGAI IMPROVEMENTS, PATENTS AND TECHNOLOGY.  Chugai hereby grants 
to MBI, and MBI hereby accepts, a perpetual license, with the right to 
sublicense, under the Chugai Improvements, the Chugai Patents and the Chugai 
Technology to develop, have developed, manufacture, have manufactured, use, 
sell, have sold and distribute the Licensed Products, all other products 
solely to the extent that they represent a modification or improvement of or 
relate to any of the Licensed Products, and all  ***  (including, without 
limitation, all  ***  that are not solely improvements or modifications of  
***).  The foregoing license shall be non-exclusive in the Territory and 
exclusive in all countries of the world outside the Territory.  The foregoing 
license shall also be royalty free (i)    ***   with respect to  ***, all 
other products solely to the extent that they represent a modification or 
improvement of or relate to  ***, and all   ***   (including, without 
limitation,  ***   that are not solely improvements or modifications of  ***) 
and (ii) for a period of  ***  from the Effective Date or, if earlier, the 
date this Agreement is terminated by Chugai pursuant to Section 11.4(b), with 
respect to ORALEX-Registered Trademark-, FS069 and all other products solely 
to the extent that they represent a modification or improvement of or relate 
to ORALEX-Registered Trademark- or FS069.  Beginning on the first day of the  
***   after the Effective Date, or, if earlier, the first day after the date 
this Agreement is terminated by Chugai pursuant to Section 11.4(b), MBI shall 
pay to Chugai a  ***  for sales of ORALEX-Registered Trademark-, FS069 and 
all other products solely to the extent that they represent a modification or 
improvement of or relate to ORALEX-Registered Trademark- or FS069, but only 
in the event that any of the Chugai Improvements, the Chugai Patents or the 
Chugai Technology licensed to MBI pursuant to this Section 2.1(b) are used by 
MBI in the manufacture, sale or distribution of ORALEX-Registered Trademark-, 
FS069 or such other products.  In the event that the parties   ***   by 
arbitration pursuant to Article 15. MBI shall give Chugai written notice 
identifying each Third Party to which MBI may sublicense any rights under 
this Section 2.1(b) prior to granting the sublicense.  Chugai agrees to 
promptly inform MBI in writing, within a reasonable time period, of the 
development of any Chugai Improvements, the issuance of any Chugai Patents 
and the development of any Chugai Technology licensed to MBI pursuant to this 
Section 2.1(b).

2.2  ADDITIONAL IMAGING PRODUCTS.  During the Term, MBI shall periodically,
including, but not limited to, at the meetings of the Task Force, provide Chugai
with information on any Additional Imaging Product and, prior to granting any
Rights for use in the field to any Third Parties in the Territory with respect
to any Additional Imaging Product, MBI shall notify Chugai in writing of MBI's
desire to offer such Rights to one or more Third Parties in the Territory (the

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"Offer Notice").  Any such Offer Notice provided by MBI to Chugai shall 
include an identification of the Additional Imaging Products,  ***.  Within   
***  after the receipt of the Offer Notice, Chugai shall inform MBI in 
writing of whether Chugai has an interest in the Additional Imaging Product.  
If Chugai informs MBI that it has no interest in the Additional Imaging 
Product, or if Chugai and MBI fail to execute a definitive agreement relating 
to such Additional Imaging Product with respect to the Territory within   *** 
after Chugai's receipt of the Offer Notice, then MBI may grant Rights with 
respect to such Additional Imaging Product to one or more Third Parties for 
use in the Field in the Territory,   ***.  All information disclosed by MBI 
pursuant to this Section 2.2 shall be deemed to be Confidential Information 
subject to the restrictions contained in Article 9.

2.3  COVENANT NOT TO MARKET OR SELL COMPETITIVE PRODUCTS.  Chugai hereby
covenants not to manufacture (except for internal development), market, sell or
distribute, either directly or through any Affiliate or Third Party, or to grant
any rights (whether by license, transfer or otherwise) to any Affiliate or Third
Party to develop, manufacture (except to Affiliates in connection with internal
development by Chugai), market, sell or distribute, any Competitive Product in
the Territory during the Term.

                                   ARTICLE 3
                       DEVELOPMENT OF LICENSED PRODUCTS

3.1  EXECUTIVE COMMITTEE.  The Executive Committee shall be comprised of six (6)
members, with three (3) appointed by MBI and three (3) appointed by Chugai. 
Within one (1) week after the date of execution of this Agreement, both parties
will notify the other party in writing of their members of the Executive
Committee.  The purpose of the Executive Committee shall be to discuss major
strategic issues related to the development and commercialization of the
Licensed Products.  All actions of the Executive Committee shall be governed by
the terms of this Agreement.  Either party may change its representative(s) on
the Executive Committee at any time by prior written notice to the other party. 
The Executive Committee shall meet at least once in each Fiscal Year, and at any
other times either party thinks necessary to meet, at such times and places as
are agreed to by MBI and Chugai, alternating between San Diego, California, and
Tokyo, Japan, or such other locations as the members of the Executive Committee
shall agree.  Meetings of the Executive Committee may be attended by such other
directors, officers and employees of each party as such party deems appropriate,
and by such consultants and non-employee agents of each party as the members of
the Executive Committee may from time to time agree.  The party hosting the
meeting of the Executive Committee shall prepare and deliver to the other party
(i) twenty (20) days prior to the date of the meeting, the agenda for the
meeting

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and (ii) within twenty (20) days after the date of the meeting, minutes of 
the meeting that set forth all discussions of the Executive Committee at the 
meeting.

3.2  TASK FORCE.  Promptly after the Effective Date, MBI and Chugai shall 
establish the Task Force.  The purpose of the Task Force will be to discuss 
day-to-day issues related to the collaboration, including the progress of 
each party in its development of the Licensed Products, the transfer of 
technology related to the Licensed Products from one party to the other, 
developments in each party's efforts to obtain Marketing Authorizations for 
each of the Licensed Products, the initial pricing of the Licensed Products 
and any significant changes to the initial pricing, the marketing, sales and 
distribution plans for each of the Licensed Products, and any other issues 
either party presents to the Task Force.  Either party may change its 
representatives on the Task Force at any time upon notice to the other party. 
 The Task Force shall meet (a) at least once every six (6) months prior to 
the commercial launch of all of the Licensed Products in Japan, (b) at such 
times as the parties may agree after the commercial launch of all of the 
Licensed Products in Japan and (c) and at any other time either party thinks 
necessary to meet, at such times and places as are agreed to by MBI and 
Chugai, alternating between San Diego, California, and Tokyo, Japan, or such 
other locations as the members of the Task Force shall agree.  Meetings of 
the Task Force may be attended by such other directors, officers and 
employees of each party as such party deems necessary, and by such 
consultants and non-employee agents of each party as the members of the Task 
Force may from time to time agree.  In addition, the party hosting the 
meeting of the Task Force shall prepare and deliver to the other party (i) at 
a reasonable time in advance of the meeting, the agenda for the meeting and 
(ii) within a reasonable time after the date of the meeting, minutes of the 
meeting that set forth all discussions of the Task Force at the meeting.  
Minutes shall be deemed approved unless any member of the Task Force objects 
to the accuracy of such minutes in writing to the other party within ten (10) 
business days of receipt.  Any dispute arising from the Task Force shall be 
presented to the Executive Committee for resolution.

3.3  CHUGAI DEVELOPMENT EFFORTS.  Chugai shall at its own expense use   ***   
(i) to carry out the Chugai Development Program for each Licensed Product, 
including without limitation, in the case of FS069, preclinical, clinical and 
process development programs for   ***; and (ii) to obtain Marketing 
Authorization as soon as practicable for each Licensed Product in each 
country in the Territory. Chugai shall be solely responsible for the conduct 
of all phases of the Chugai Development Program for each Licensed Product, 
including but not limited to clinical trials specified therein.  Chugai shall 
provide, at the meetings of the Task Force, regular updates on the progress 
of the Chugai Development Program for each Licensed Product and shall consult 
with MBI before making any changes to the Chugai Development Program for any 
of the Licensed Products.  At Chugai's request, MBI shall   ***.  All 
information disclosed by MBI   ***  shall be deemed to be Confidential 
Information subject to the restrictions contained in Article 9.  Subject to 
the first sentence of this Section 3.3, MBI acknowledges and agrees that 
Chugai shall have the right to modify or discontinue the Chugai Development 
Program for each Licensed

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Product   ***

3.4  FILING FOR MARKETING APPROVAL FOR FS069.  In addition to Chugai's 
obligation to use  ***  to develop FS069 as set forth in Section 3.3, 
Chugai shall file in Japan an application for Marketing Authorization with 
the Competent Authorities for FS069 for  ***.  In the event that Chugai 
has not filed   ***  prior to the end of the  ***, Chugai may obtain a  *** 
of the deadline to file   ***   not filed prior to such date by paying to 
MBI  ***   prior to the end of the  ***. If  ***  filed with the Competent 
Authorities prior to the end of the  ***, the payment made by Chugai 
pursuant to the end of the  ***  shall be credited to Chugai's milestone 
obligations under Section 5.2.  If   ***   are not filed prior 
to the end of the   ***, then MBI shall have the option as set forth in 
Section 11.2 to convert the license granted to Chugai pursuant to Section 
2.1(a) with respect to FS069 to a non-exclusive license.  The above   ***   
deadlines shall   ***   be extended in the event that (i) the issuance of an 
injunction by a court of competent jurisdiction prohibits Chugai from 
continuing the development of FS069 as a result of the infringement of FS069 
on one or more patents held by Third Parties or (ii) Chugai's failure to file 
in Japan an application for Marketing Authorization with the Competent 
Authorities for FS069 for   ***   is primarily the result of MBI's breach of
its obligations under this Agreement.  The length of the extension of the   
  ***   deadlines shall be day for day based on the length of the delay 
resulting from items (i) or (ii) above.  In addition, in the event that 
Chugai's filing of   ***  for Marketing Authorization required by this 
Section 3.4 is substantially delayed compared to the timing of filings by 
similarly situated companies in Japan as a result of irregularities in 
regulatory actions by the Competent Authorities, then Chugai will provide a 
detailed explanation of the events to MBI and both parties will discuss the 
reasons for the delay in good faith.

3.5  DISCONTINUANCE OF CHUGAI'S DEVELOPMENT EFFORTS.  Chugai shall be 
entitled,  ***, to discontinue the Chugai Development Program at any time 
with respect to one or more of the Licensed Products.  In the event that 
Chugai  ***  discontinue the Chugai Development Program with respect to any 
Licensed Product, (a) Chugai shall notify MBI promptly in writing of its 
decision, (b) all licenses granted to Chugai with respect to the Licensed 
Product shall terminate immediately, (c) all rights to the Licensed Product 
shall revert immediately to MBI, (d) Chugai shall pay to MBI, concurrently 
with the notice described in (a) above, all then-unpaid license fees 
described in Section 5.1, whether then due or not, and (e) Chugai shall 
comply with the provisions of Section 11.4.

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3.6  MBI'S DEVELOPMENT EFFORTS.

     (a)  MBI shall, either itself or through its Licensees and at no expense 
to Chugai, use  ***  to conduct a development program in the United States 
relating to the use of ORALEX-Registered Trademark- and FS069 for the Initial 
Targeted Indications and for other future  ***.  A description of the 
clinical studies MBI currently expects to conduct as its development program 
for ORALEX-Registered Trademark- and FS069 are set forth on Exhibit 3.6(a), 
attached hereto and made a part hereof.  Chugai acknowledges and agrees that 
the description of the clinical studies set forth on Exhibit 3.6(a) 
represents the types of studies that MBI presently anticipates it will 
conduct and that the clinical studies described on Exhibit 3.6(a) shall be 
subject to modification or discontinuance at any time by MBI in its sole 
discretion as it deems appropriate (after consulting with and providing  *** 
to Chugai).  MBI will  ***.  MBI shall provide, at the meeting of the Task 
Force, regular updates on the progress of the development program.  All 
information disclosed to Chugai pursuant to this Section 3.6(a) shall be 
deemed to be Confidential Information subject to the restrictions contained 
in Article 9.

     (b)  MBI shall use  ***  to conduct the MBI Development Program with 
respect to   ***.  The goal of the MBI Development Program is to  ***.  
Chugai acknowledges and agrees that the  ***   to be conducted by MBI as the 
MBI Development Program shall be subject to  ***.  MBI shall provide, at the 
meeting of the Task Force, regular updates of the MBI Development Program.  
Chugai shall reimburse MBI for all MBI Development Costs with respect to   
  ***  as set forth in Section 5.6 below.

     (c)  MBI shall make all decisions in its sole discretion with respect to
the development of the Licensed Products outside the Territory and shall make a
presentation at least once each Fiscal Year at a meeting of the Executive
Committee regarding its development of the Licensed Products outside the
Territory.

3.7  COORDINATION AMONG LICENSEES.  MBI shall use reasonable efforts (a) to
provide Chugai with any information obtained by MBI from any Licensee regarding
any adverse reaction involving a Licensed Product, subject to any limits on
MBI's ability to share such material information with Chugai contained in any
agreement between MBI and any such Licensee, and (b) to provide Chugai with any
publicly available, non-confidential promotional data and materials developed by
any Licensee.  Chugai agrees that is shall not, nor shall it permit any of its
Affiliates, sublicensees or distributors to, contact any such Licensee or
participate in any oral or written discussions or meetings with any such
Licensee without first notifying MBI and enabling MBI to participate in all such
discussions and to be present at all such meetings.

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3.8  PUBLICATIONS.  In the event Chugai proposes to publish or publicly 
present the results of its development activities with respect to any MBI 
Technology, MBI Improvements or MBI Patents, or if MBI proposes to publish or 
publicly present the results of its development activities with respect to 
any Chugai Technology, Chugai Improvements or Chugai Patents (in either case, 
the "Results"), Chugai or MBI, as the case may be (the "Publishing Party") 
shall submit to the other party (the "Published Party") for comment a draft 
of any proposed manuscript, abstract or speech regarding the Results at least 
  ***   prior to submission for publication or oral presentation.  The 
Published Party shall notify the Publishing Party in writing within   ***  
after receipt of such draft whether such draft contains Confidential 
Information of the Published Party, or information that if published or 
publicly presented would have an adverse effect on a patent application filed 
or to be filed by the Published Party ("Adverse Patent Information").  The 
Publishing Party shall not publish or publicly present any Confidential 
Information of the Published Party, and the Publishing Party shall delay the 
publication or public presentation of any Adverse Patent Information for the 
period of time requested by the Published Party, which shall be the period of 
time determined by the Published Party to be sufficient to enable it to file 
all patent applications it desires to file.  The Publishing Party shall cause 
its Affiliates, sublicensees, distributors and Third Party as the case may 
be, to comply with the requirements of this Section 3.8 with respect to any 
of their proposed publications.

                                  ARTICLE 4
                              COMMERCIALIZATION

4.1  PRODUCT LAUNCH.  Chugai shall initiate distribution and marketing of 
each Licensed Product in each country in the Territory upon receipt of 
Marketing Authorization required in such country and shall ensure that the 
First Commercial Sale of each Licensed Product occurs in each country in the 
Territory (i) no later than   ***   after receipt of all Pricing and 
Reimbursement Approvals required by the country for such Licensed Product or 
(ii) if no Pricing and Reimbursement Approvals are required in any country in 
the Territory, no later than   ***   after receipt of Marketing Authorization 
required in such country for such Licensed Product.  In the event that, at 
the time Chugai receives all Pricing and Reimbursement Approvals or Marketing 
Authorizations required in any country in the Territory for any Licensed 
Product,   ***, then the parties will in good faith   ***  the First 
Commercial Sale of the Licensed Product   ***.

4.2  PROMOTION AND MARKETING OBLIGATIONS.

     (a)  MARKETING EFFORTS.  Chugai agrees to use   ***   to promote the 
sale, marketing and distribution of each of the Licensed Products in each 
country in the Territory,   ***.  Chugai shall promptly advise MBI of any 
material issues that adversely affect Chugai's ability to market the Licensed 
Products in the Territory including, but not limited to,   ***.  In such 
event, Chugai and MBI shall discuss in good faith   ***   provided

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                                      -14-

<PAGE>

that neither party shall have any liability hereunder in the event   ***.

     (b)  GENERAL CONDUCT.  Chugai hereby covenants that it will not promote,
solicit or make sales of Licensed Products or advertise Licensed Products
outside of the Territory.  Chugai shall not, directly or indirectly, without the
prior written authorization of MBI contact any Competent Authority outside the
Territory regarding the Licensed Products.  Chugai shall cause each of its
Affiliates, sublicensees and distributors to comply with this Section 4.2(b). 
MBI hereby covenants that it will not promote, solicit or make sales of Licensed
Products or advertise Licensed Products in the Territory during the Term, except
to the extent permitted under Section 11.2 or 11.3.  MBI shall not, directly or
indirectly, without the prior written authorization of Chugai (which shall not
be unreasonably withheld or delayed), contact any Competent Authority about the
Licensed Products, except as required by Applicable Laws or as may be necessary
or appropriate to carry out its obligations hereunder.

     (c)  TRADEMARK(S).  MBI shall have the right to select one or more 
trademark(s) for use in connection with the promotion, marketing and sale of 
each Licensed Product outside the Territory, which trademark(s) shall be 
owned by MBI and   ***   Chugai is hereby granted an  *** license in the 
Territory to use such trademark(s) solely for such purposes. Notwithstanding 
the foregoing   ***.  Chugai shall have the right to select one or more 
trademark(s) for use in connection with the promotion, marketing and sale of 
each Licensed Product in the Territory.  Chugai shall consult with MBI prior 
to selecting any such trademark(s).

     (d)  SALES FORECASTS. No later than   ***   prior to the expected date 
of First Commercial Sale of each Licensed Product and no later than   ***   
prior to the start of each Fiscal Year thereafter, Chugai shall deliver to 
MBI, for review by MBI, a forecast of the number of the Product Units of the 
Licensed Product that Chugai expects it and its Affiliates, sublicensees and 
distributors to sell during each of the next Fiscal Year.

     (e)  PHASE IV SURVEILLANCE; MARKETING TRIALS.  Chugai shall be 
responsible for any Phase IV surveillance programs (or their functional 
equivalent) in the Territory for the Licensed Products, which shall be 
conducted in accordance with Applicable Laws.  Chugai shall be responsible 
for the conduct of any marketing trials that it determines are necessary.  
All expenses incurred in the Territory pursuant to this Section 4.2(e) shall 
be borne by Chugai.  Any interim data and results in written form of such 
surveillance programs and marketing trials shall be

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                                     -15-
<PAGE>

promptly provided to MBI in writing, and MBI  ***  shall have the right to 
incorporate, refer to and cross-reference such results and underlying data in 
any regulatory filing made by MBI  ***  outside the Territory or inside the 
Territory but outside the Field.  Further, Chugai agrees that should 
Applicable Laws require that any such interim data and results from such 
programs and trials be prepared in written form, Chugai shall comply with 
such requirements and provide all such information in writing to MBI, 
Competent Authorities as required by Applicable Laws and any  ***   
governmental agencies specified by MBI.  MBI shall provide promptly to Chugai 
any interim data and results in written form from any Phase IV surveillance 
programs or marketing programs with respect to the Licensed Products that are 
conducted by MBI  ***, and Chugai shall have the right to incorporate, refer 
to and cross-reference such results and underlying data in any regulatory 
filing made by Chugai, its Affiliates or its sublicensees in the Territory.  
MBI agrees that should Applicable Laws require that any such interim data and 
results from such programs and trials be prepared in written form, MBI shall 
comply with such requirements and provide all such information in writing to 
Chugai and Competent Authorities as required by Applicable Laws.  Chugai 
shall not be responsible for any expenses incurred outside the Territory 
pursuant to this Section 4.2(e).

                                  ARTICLE 5
                    ROYALTY AND MILESTONE PAYMENTS TO MBI

5.1  LICENSE FEE.  Chugai shall pay MBI a nonrefundable license fee of 
Fourteen Million Dollars ($14,000,000), of which  ***  shall be allocated 
to the license of FS069 and  ***  shall be allocated to the license of 
ORALEX-Registered Trademark-.  ***  of the total license fee has already 
been paid by Chugai.  The remaining  ***  shall be payable at the times 
and in the amounts specified below:

     Date of Payment                    Payment Amount

          ***
                                              ***
          ***
                                              ***
          ***
                                              ***
          ***
                                              ***

          ***                                 ***

5.2       MILESTONE PAYMENTS.  Chugai shall pay to MBI nonrefundable milestone
payments (the "Milestone Payments") at the times and in the amounts specified
below upon the occurrence of the corresponding events designated below:

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                                     -16-

<PAGE>

          (a)   ***.  Within   ***   after the   ***   by or on behalf of 
Chugai or any of its Affiliates or sublicensees   ***, Chugai shall pay to 
MBI a Milestone Payment equal to   ***.

          (b)   ***.  Within   ***   after the   ***   by or on behalf of 
Chugai or any of its Affiliates or sublicensees   ***, Chugai shall pay to 
MBI a Milestone Payment equal to   ***.

          (c)   ***.  Within   ***   after the   ***   by or on behalf of 
Chugai or any of its Affiliates or sublicensees  ***, Chugai shall pay to 
MBI a Milestone Payment equal to   ***.

          (d)   ***.  Within   ***   after the   ***   by or on
behalf of Chugai or any of its Affiliates or sublicensees   ***, Chugai
shall pay to MBI a Milestone Payment equal to   ***.

          (e)   ***.  Within   ***   after the   ***   by Chugai or any of 
its Affiliates or sublicensees   ***, Chugai shall pay to MBI a Milestone 
Payment equal to   ***.

          (f)   ***.  Within   ***   after the   ***   by Chugai or any of 
its Affiliates or sublicensees   ***, Chugai shall pay to MBI a Milestone 
Payment equal to   ***.

          In the event that Chugai pursues the development of   ***, and 
achieves the milestone events described above for   ***, then the Milestone 
Payments that would have been payable pursuant to this Section 5.2 on the   
***, as the case may be, shall be owing by Chugai on the other   ***   
developed by Chugai.

5.3       EARNED ROYALTIES.  Chugai shall pay to MBI, each Calendar Quarter, 
a royalty based upon annual Net Sales.  The royalty schedule described below 
shall be calculated based upon Net Sales generated during each Fiscal Year, 
so that aggregate Net Sales are separately computed for each Fiscal Year.  
With respect to any Fiscal Year during which this Agreement is not in effect 
for every day of such Fiscal Year, Net Sales shall be calculated based upon 
Net Sales generated during the portion of such Fiscal Year during which this 
Agreement is in effect. The percentage of the annual Net Sales shall be as 
follows:






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                                      -17-

<PAGE>

          (a)   ***.  With respect to Net Sales of Licensed Products   ***, 
Chugai shall pay a royalty on annual Net Sales according to the following 
schedule:
               
               (i)   ***   on that portion of annual Net Sales that are    ***;

               (ii)  ***   on that portion of annual Net Sales that are    
***; and

               (iii) ***   on that portion of annual Net Sales that are    ***.

          (b)   ***.  With respect to Net Sales of Licensed Products   ***, 
Chugai shall pay a royalty equal to   ***   of annual Net Sales.

5.4       PURCHASE PRICE FOR LICENSED PRODUCTS.  In the event that Chugai 
purchases any of the Licensed Products from MBI for commercial supply, then 
in addition to the earned royalty described in Section 5.3(a) above, Chugai 
shall pay to MBI an amount for each Product Unit purchased from MBI equal to  
***  of the average Net Sales price for all Product Units of the same 
Licensed Product sold by Chugai, its Affiliates, sublicensees and 
distributors during the prior Calendar Quarter.  Chugai shall calculate such 
average Net Sales price and deliver to MBI a detailed written report 
describing the calculation of such average Net Sales price no later than 
forty-five (45) days after the end of each Calendar Quarter.  All sales of 
Licensed Product after the end of any Calendar Quarter and prior to MBI's 
receipt of Chugai's report shall be at the price in effect for the Calendar 
Quarter preceding the Calendar Quarter just ended, and an adjustment shall be 
made on the first invoice delivered to Chugai after MBI's receipt of the 
report so that the price paid by Chugai for such Licensed Product is equal to 
***  of the average Net Sales price for all Product Units of the same 
Licensed Product sold by Chugai, its Affiliates, sublicensees and 
distributors during the immediately preceding Calendar Quarter. Concurrently 
with each shipment of Licensed Product, MBI shall invoice Chugai. The invoice 
shall be due and payable   ***   after shipment by MBI of the Product Units.  
All payments owing to MBI under this Section 5.4 shall be made in accordance 
with the provisions of Article 6.

5.5       ANNUAL MINIMUM ROYALTIES   ***.  In the event that in the   *** 
or any Fiscal Year thereafter during the Term, the sum of Chugai's total 
annual royalty payments to MBI pursuant to Section 5.3 above with respect to 
sales of the   ***   for such Fiscal Year plus the total amount, if any, paid 
by Chugai pursuant to Section 5.4 above for the purchase of   ***   from MBI 
(such sum shall be the "Payment Sum") is less than the annual minimum payment 
set forth opposite such Fiscal Year below (the "Annual Minimum"), Chugai 
shall pay to MBI the






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                                     -18-

<PAGE>

Shortfall (as defined below).  The Shortfall shall be paid by Chugai to MBI 
as required by Section 6.1 below.  In the event that Chugai purchases any of  
 ***   during any Fiscal Year for which an Annual Minimum is due, the Annual 
Minimum owing by Chugai to MBI shall be the amount set forth under the 
heading "Annual Minimum with purchase of any   ***."  In the event that 
Chugai does not purchase any of   ***   during any Fiscal Year for which an 
Annual Minimum is due, the Annual Minimum owing by Chugai to MBI shall be the 
amount set forth under the heading "Annual Minimum without purchase of any   
***."  The "Shortfall" shall equal the difference between (a) the applicable 
Annual Minimum for such  Fiscal Year and (b) the Payment Sum for such Fiscal 
Year.  The Annual Minimum shall not be applicable in the event that MBI 
converts the license granted to Chugai with respect to   ***.

<TABLE>
<CAPTION>
                          Annual Minimum      Annual Minimum
                           With Purchase     Without Purchase
Fiscal Year                  Of Any ***          Of Any ***
- -------------------------------------------------------------
<S>                              <C>                 <C>
   ***                           ***                 ***

   ***                           ***                 ***

   ***                           ***                 ***

   ***                           ***                 ***

   ***                           ***                 ***
</TABLE>

5.6       FUNDING OF MBI DEVELOPMENT COSTS.  Chugai shall pay all MBI 
Development Costs with respect to   ***.  MBI will provide Chugai, no later 
than thirty (30) days after the last day of each Calendar Quarter, a 
statement of the MBI Development Costs MBI incurred in conducting the MBI 
Development Program during such Calendar Quarter (a "Quarterly Statement").  
Chugai shall pay MBI in U.S. dollars in the United States within thirty (30) 
days after the date of the Quarterly Statement the amount invoiced as owing 
to MBI in the Quarterly Statement.  

5.7       REPAYMENT OF MBI DEVELOPMENT COSTS; USE OF CHUGAI DATA. In the 
event that MBI, directly or through any Third Party, sells   ***, MBI shall 
pay to Chugai   ***   of the MBI Development Costs previously paid by Chugai 
to MBI.  In the event that MBI, directly or through any Third Party, 
thereafter sells   ***, MBI shall pay to Chugai an additional   ***   of the 
MBI Development Costs previously paid by Chugai to MBI.  In the event that 
MBI incorporates the data from any preclinical test or clinical trial 
conducted by Chugai under the Chugai Development Program in either a New Drug 
Application filed with   ***   for a Licensed Product or in an application 
that is reasonably functionally equivalent to a New Drug Application with the 
appropriate regulatory authorities in   ***   for a Licensed Product , MBI 
shall pay to Chugai   ***   of the direct costs incurred by Chugai in 
conducting such preclinical test or clinical trial.  In the event that MBI 
thereafter incorporates such data in both a New Drug Application filed with   
***   for a Licensed Product and in an application that is reasonably 
functionally equivalent to a New Drug Application with the appropriate




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                                     -19

<PAGE>

regulatory authorities in   ***   for a Licensed Product, MBI shall pay to 
Chugai an additional  ***   of the direct costs incurred by Chugai in
conducting such preclinical test or clinical trial.  

5.8       RECORDS AND AUDIT.  MBI shall keep complete and accurate Records of 
the MBI Development Costs.  MBI shall permit Chugai, at Chugai's expense, by 
its own accountants or by independent certified public accountants reasonably 
acceptable to MBI, to examine the Records of the MBI Development Costs during 
MBI's normal business hours with reasonable notice, but not more than  ***  
per Fiscal Year and not later than   ***   following the date the Record was 
created. Chugai's accountants shall maintain in confidence, and the 
independent public accountants selected by Chugai shall, as a condition to 
such examination, execute a written agreement reasonably satisfactory to MBI 
to maintain in confidence, all information obtained during the course of any 
such examination, except for disclosure of the details and the results of the 
examination to Chugai.  MBI, provided that it agrees with the results of the 
examination, shall immediately pay to Chugai the amount of any overpayment by 
Chugai of MBI Development Costs revealed by the examination with interest 
calculated from the date(s) of overpayment by Chugai at the rate of   ***   
per month or, if lower, the maximum rate allowed by law.  Any dispute 
regarding the results of the examination that the parties are not able to 
resolve by mutual agreement shall be resolved in accordance with the dispute 
resolution provisions of Article 15.  In the event the amount of any 
overpayment by Chugai as finally determined is   ***   or more of the amount 
of MBI Development Costs subject to examination, MBI shall pay Chugai all 
reasonable costs and expenses incurred by Chugai associated with such 
examination within fifteen (15) days after written demand by Chugai.

                                    ARTICLE 6
                     PROCEDURE FOR PAYMENTS; RECORDS; AUDIT

6.1       MANNER AND PLACE OF PAYMENT.  Chugai shall pay to MBI the total 
amounts due under Sections 5.1, 5.2, 5.4 and 5.6 within the times set forth 
therein.  Chugai shall also pay to MBI the total amounts due under Sections 
5.3 and 5.5 within forty-five (45) days after the end of each Calendar 
Quarter, such payments in each case to be accompanied by a detailed written 
report by Chugai showing the calculation of Net Sales of each Licensed 
Product divided country-by-country in the Territory, including the quantities 
of the Product Units of each of the Licensed Products sold, the price at 
which the Product Units of each of the Licensed Products were sold, the 
royalties payable under this Agreement on the sales of the Product Units of 
each of the Licensed Products during the reporting period, the exchange rates 
used in converting any foreign currencies to United States dollars in the 
calculation of such royalties, the withholding taxes, if any, required by law 
to be deducted from such royalties and such other details as MBI may 
reasonably request.  The royalty rate used to calculate royalty payments due 
under Section 5.3 shall be based upon actual Net Sales through the date of 
calculation in such Fiscal Year.  To the extent that the Payment Sum for any 
Calendar Quarter during any Fiscal Year, when added to the previous Payment 
Sums and Shortfall payments, if any, actually paid by Chugai for earlier 
Calendar Quarters during the same Fiscal Year, is less than the pro rata 
portion of the applicable Annual Minimum for such Fiscal Year (with the 
applicable Annual Minimum (i) determined based on whether Chugai has 
purchased any of   ***


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                                     -20-

<PAGE>

from MBI during such Fiscal Year and (ii) calculated based upon the portion 
of the Fiscal Year covered by the relevant Calendar


























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                                      -21

<PAGE>

Quarter plus all previous Calendar Quarters of such Fiscal Year), then Chugai 
shall pay to MBI the Shortfall for such Calendar Quarter equal to the amount 
that, when added to the Payment Sum for such Calendar Quarter and the 
previous Payment Sums and Shortfall payments, if any, actually paid by Chugai 
under Section 5.5 for earlier Calendar Quarters during the same Fiscal Year, 
equals the pro rata portion of the applicable Annual Minimum (determined and 
calculated as set forth above in this sentence).  With respect to all 
royalties payable to MBI on sales of the Licensed Products pursuant to 
Section 5.3 invoiced in any currency other than United States dollars, the 
gross sales, Net Sales and royalties payable to MBI shall be expressed in the 
report required by this Section 6.1 in the foreign currency together with the 
United States dollar equivalent of the royalties payable to MBI, calculated 
using the average of the buying and selling exchange rates quoted by   ***   
(or any other bank mutually agreed to by both Chugai and MBI) at the close of 
business on the last banking day of the applicable Calendar Quarter.  All 
payments to MBI under this Agreement shall be made by wire transfer to an 
account of MBI designated by MBI from time to time and shall be made in U.S. 
Dollars.

6.2       RECORDS AND AUDIT.  Chugai shall keep, and shall cause each of its 
Affiliates, sublicensees and distributors to keep, complete and accurate 
Records.  Chugai shall permit MBI, and shall cause each of its Affiliates, 
sublicensees and distributors to permit MBI, at MBI's expense, by its own 
accountants or by independent certified public accountants reasonably 
acceptable to Chugai, to examine the Records during Chugai's normal business 
hours with reasonable notice, but not more than  ***  per Fiscal Year and not 
later than    ***   following the date the Record was created.  MBI's 
accountants shall maintain in confidence, and the independent public 
accountants selected by MBI shall, as a condition to such examination, 
execute a written agreement reasonably satisfactory to Chugai to maintain in 
confidence, all information obtained during the course of any such 
examination, except for disclosure of the details and the results of the 
examination to MBI.  Chugai, provided that it agrees with the results of the 
examination, shall immediately pay to MBI the amount of any underpayment by 
Chugai revealed by the examination with interest calculated from the date(s) 
the underpayment(s) was initially due by Chugai at the rate of   ***   per 
month or, if lower, the maximum rate allowed by law.  Any dispute regarding 
the results of the examination that the parties are not able to resolve by 
mutual agreement shall be resolved in accordance with the dispute resolution 
provisions of Article 15.  In the event the amount of any underpayment by 
Chugai as finally determined is   ***   or more of the amount in aggregate 
subject to examination, Chugai shall pay MBI all costs and expenses incurred 
by MBI associated with such examination within fifteen (15) days after 
written demand by MBI.

6.3       WITHHOLDING TAXES.  Payments to MBI hereunder shall be made without
deduction other than such amount (if any) as Chugai is required by law to deduct
or withhold.  Chugai shall obtain a receipt from the relevant taxing authorities
for all withholding taxes paid and forward such receipts to MBI to enable MBI to
claim any and all tax credits for which it may be eligible.  Chugai shall use
reasonable commercial efforts to enable or assist MBI to claim exemption from
such deductions or withholdings under any double taxation or similar agreement
or treaty from time to time in force.

6.4       PRODUCT BUNDLING.  In the event Chugai or any of its Affiliates,
sublicensees or distributors sells or transfers Product Units of any of the
Licensed Products in conjunction with


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                                      -22-

<PAGE>

any other product and in so doing sells or transfers the Product Units for an 
amount less than the lowest selling price for the Product Units sold 
separately, for the purposes of determining Net Sales from such sales or 
transfers, Net Sales shall be based upon the Net Sales price to a similar 
size customer ordering a similar volume of Product Units under similar but 
unbundled terms and conditions.

                                   ARTICLE 7
                 MANUFACTURE AND SUPPLY OF LICENSED PRODUCTS

7.1       MANUFACTURE AND SUPPLY OF LICENSED PRODUCTS.

          (a)  Chugai may manufacture or have manufactured the Licensed 
Products pursuant to the license granted under Section 2.1 above.  MBI shall 
provide reasonable assistance to Chugai in connection with the manufacture of 
the Licensed Products, which assistance shall include, if reasonably 
requested by Chugai, reasonable assistance to Chugai in identifying and 
communicating with suppliers of components of Licensed Products, and Chugai 
shall reimburse MBI for the reasonable lodging, meal and travel expenses (and 
all other travel-related expenses) incurred in providing the assistance to 
Chugai within thirty (30) days of receipt of an invoice for such travel 
expenses.  MBI's obligation to provide reasonable assistance to Chugai 
pursuant to the preceding sentence shall not exceed   ***   of assistance for 
each of the Licensed Products.  In the event that Chugai requests additional 
assistance in excess of the   ***   provided for above, MBI will use 
reasonable efforts to provide such additional assistance to Chugai on terms 
mutually agreed upon by MBI and Chugai. In the event that the parties are not 
able to agree on the terms under which such assistance will be provided to 
Chugai, MBI shall use   ***   to provide such assistance to Chugai   ***.  
Chugai's right to appoint a Third Party supplier to manufacture any of the 
Licensed Products for Chugai shall be subject to the Third Party supplier 
executing a binding contract between MBI and the Third Party supplier to 
manufacture the Licensed Products on terms acceptable to MBI.

          (b)  MBI shall use   ***   to manufacture and supply to Chugai   
***   quantity of FS069 and ORALEX-Registered Trademark- solely for use in 
the preclinical tests and clinical trials to be conducted as part of the 
Chugai Development Program, in each case until such time as Chugai obtains 
Marketing Authorization in Japan for FS069 and ORALEX or such time as Chugai 
is able itself or through one or more Affiliates or Third Parties to 
manufacture or have manufactured FS069 and ORALEX-Registered Trademark- that 
can be used in clinical trials, in each case whichever occurs first.

          (c)  If requested in writing by the other party, MBI and Chugai shall
discuss the terms under which each party would provide backup manufacturing
capabilities for the other.  The parties acknowledge that any backup
manufacturing arrangement would need to be mutually acceptable, and that neither
party shall have any liability hereunder in the event the parties are not able
to agree on the terms for such an arrangement.

          (d)  In the event that Chugai develops   ***, Chugai shall provide
reasonable assistance to MBI in connection with the manufacture of   ***, and


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                                     -23-

<PAGE>

MBI shall reimburse Chugai for the reasonable lodging, meal and travel 
expenses (and all other travel-related expenses) incurred in providing the 
assistance to MBI within thirty (30) days of receipt of an invoice for such 
travel expenses.  Chugai's obligation to provide reasonable assistance to MBI 
pursuant to the preceding sentence shall not exceed   ***   of assistance.  
In the event that MBI requests additional assistance in excess of the   ***   
provided for above, Chugai will use reasonable efforts to provide such 
additional assistance to MBI on terms mutually agreed upon by Chugai and MBI. 
In the event that the parties are not able to agree on the terms under which 
such assistance will be provided to MBI, Chugai shall use   ***   to provide 
such assistance to MBI   ***. 

7.2       ORDERS FOR CLINICAL SUPPLIES.  All orders for FS069 and 
ORALEX-Registered Trademark- pursuant to Section 7.1(b) shall be in writing 
and in the English language, shall be delivered to MBI as soon as reasonably 
practicable and shall include a requested delivery date, which date shall be 
not less than   ***   after the date of the order.  In ordering and 
delivering FS069 and ORALEX-Registered Trademark- under this Agreement, MBI 
and Chugai may use their standard forms, but nothing in any such form shall 
be construed to amend or modify the terms of this Agreement, and in the case 
of conflict herewith, the terms of this Agreement shall control.

7.3       DELIVERY OF CLINICAL SUPPLIES.  MBI shall use   ***   to deliver 
the quantities requested by Chugai within   ***   after the receipt of any 
order and shall assist Chugai in arranging any desired insurance (in amounts 
that Chugai shall determine) and transportation (via the method selected by 
Chugai) to the point of delivery requested by the Chugai.  All customs, 
duties, costs, taxes, insurance premiums and other expenses relating to such 
transportation and delivery, shall be at Chugai's expense.

7.4       NO WARRANTY.  MBI MAKES NO WARRANTIES WITH RESPECT TO THE CLINICAL 
SUPPLIES PROVIDED TO CHUGAI PURSUANT TO THIS AGREEMENT AND MBI DISCLAIMS ALL 
WARRANTIES EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY, 
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.

                                  ARTICLE 8
                  MARKETING AUTHORIZATIONS; OTHER REGULATORY
                              COMPLIANCE ISSUES

8.1       SUPPLY OF DATA.  MBI shall use reasonable efforts to provide Chugai 
with all data, including any documents filed or submitted to the FDA as part 
of any Investigational New Drug Application or New Drug Application for any 
of the Licensed Products, that is owned by MBI, is in MBI's possession and 
that MBI is not prohibited under to the terms of any agreement between MBI 
and any Third Party from disclosing to Chugai, to assist Chugai in obtaining 
Marketing Authorizations for the Licensed Products in the Territory.  If 
either party discovers any errors in the data, MBI shall promptly correct the 
error and send the corrected data to Chugai.



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<PAGE>

8.2       OBTAINING MARKETING AUTHORIZATIONS.  Chugai shall comply with 
Applicable Laws with respect to obtaining Marketing Authorizations for all 
countries in the Territory.  Chugai agrees to notify MBI in writing within 
fifteen (15) days of receipt of each Marketing Authorization.

8.3       MARKETING AUTHORIZATION HOLDER.  Unless otherwise required by 
Applicable Laws, Chugai or its Affiliates shall be the holder of all 
Marketing Authorization in the Territory.  Chugai, its Affiliates or 
sublicensees will not transfer, assign, mortgage, charge or sub-contract any 
of the Marketing Authorizations other than to MBI or to a Third Party 
sublicensee or distributor approved in writing by MBI and sublicensed or 
appointed by Chugai to distribute the Licensed Product, and Chugai will not 
do anything that might adversely affect any of the Marketing Authorizations.  
Any transfer of the Marketing Authorization by Chugai or its Affiliates to a 
Third Party sublicensee or distributor shall be subject to MBI's prior 
written approval (which shall not be unreasonably withheld).  Chugai agrees 
to provide MBI with appropriate evidence from the Competent Authorities 
documenting the transfer of any Marketing Authorization within thirty (30) 
days of the effective date of any transfer of the Marketing Authorization.  
Any transfers of a Marketing Authorization made in violation of this Section 
8.3 shall be null, void and unenforceable.  The term "transfer" shall 
include, but not be limited to, transfers from Chugai or its Affiliates to a 
Third Party sublicensee or distributor of an existing Marketing Authorization 
as well as cases in which the Third Party sublicensee or distributor rather 
than Chugai or one of its Affiliates makes an application for a Marketing 
Authorization.

8.4       MARKETING AUTHORIZATIONS AND PRE-MARKETING EXPENSES.  Chugai shall 
pay all costs and expenses incurred in seeking and maintaining all Pricing 
and Reimbursement Approvals and Marketing Authorizations in the Territory.  
Chugai shall also pay all costs and expenses relating to the marketing, sale 
or distribution of any Licensed Product in the Territory that are incurred 
prior to the First Commercial Sale of the Licensed Product in the Territory, 
including all such costs and expenses that are incurred by MBI that are 
approved by Chugai in writing in advance.

8.5       PROVISION OF REGULATORY FILINGS.  Chugai shall provide MBI with 
copies of all filings made to the Competent Authorities in the Territory 
relating to the Licensed Products filed in accordance with this Article 8.

8.6       ASSISTANCE.  Each party shall provide reasonable assistance to the 
other at the other's request, in connection with the other's performance of 
its obligations pursuant to this Article 8, subject to reimbursement of the 
assisting party's out-of-pocket costs and expenses.

8.7       ADVERSE REACTION REPORTING.  Each party shall advise the other 
party of the occurrence of any adverse events with respect to the Licensed 
Products within such time as will permit the other party to comply with 
Applicable Laws.  Within thirty (30) days before the First Commercial Sale or 
any test or trial conducted on a Licensed Product by Chugai or its 
Affiliates, sublicensees or distributors, the parties shall agree upon and 
finalize the SOP, provided that such SOP shall be Chugai's current SOP, 
modified only to the extent necessary to provide a mechanism for Chugai to 
provide information to MBI that is necessary under Applicable Laws for MBI to 
provide to the FDA.  The parties agree to follow the SOP in the Territory.

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<PAGE>

8.8       POST-FIRST COMMERCIAL SALE TESTING AND REPORTING.  If, after the 
date of First Commercial Sale in any country in the Territory, adverse events 
or other issues arise with respect to the safety or efficacy of a Licensed 
Product that jeopardize the Licensed Product's performance or are deemed by 
either party to potentially limit its approved indications, the parties shall 
consult with each other with respect to such events or other issues.  If the 
parties determine that the situation requires clinical testing after the 
First Commercial Sale in any country in the Territory, modifications to any 
Marketing Authorization or other communication with any Competent Authority 
or entity, MBI and Chugai shall cooperate to design and the parties shall 
implement any such testing, modifications or communication as shall be agreed 
upon by the parties; provided, however, that Chugai may communicate with any 
Competent Authority to the extent it deems necessary or appropriate to 
fulfill its obligations hereunder.   ***

8.9       PRODUCT RECALL.  Chugai and MBI each shall notify the other 
promptly if any Licensed Product is the subject of a recall, market 
withdrawal or correction in the Territory, and the parties shall reasonably 
cooperate in the handling and disposition of such recall, market withdrawal 
or correction; provided, however, in the event of a disagreement as to any 
matters related to such recall, market withdrawal or correction, other than 
the determination of who shall bear the costs as set forth in the immediately 
following sentence, each party shall have the right to cause a recall, market 
withdrawal or correction to be made.  MBI shall bear all costs of all 
recalls, market withdrawals or corrections of the Licensed Products that are 
caused by   ***. Chugai shall in all events be responsible for conducting any 
recalls, market withdrawals or corrections with respect to the Product Units, 
and in doing so shall consult with MBI.  Chugai shall maintain Records of all 
sales and distribution of Product Units and customers sufficient to 
adequately administer a recall, market withdrawal or correction for a period 
of five (5) years after the date the Record is created.

8.10      REPORTS.  Each party shall keep the other fully informed of all 
governmental activities and plans that potentially or actually affect the 
sale of the Licensed Product in the Territory to the extent that each such 
party has knowledge of such activities and plans.







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                                  ARTICLE 9
                               CONFIDENTIALITY

9.1       NONDISCLOSURE OBLIGATIONS.  During the Term, and for a period of 
   ***    after termination hereof, each party (the "receiving party") 
will maintain all Confidential Information of the other party (the 
"disclosing party") in trust and confidence and will not disclose any 
Confidential Information of the disclosing party to any Third Party or use 
any Confidential Information of the disclosing party for any purpose other 
than to the extent required to satisfy its obligations under this Agreement.  
Confidential Information of the disclosing party shall not be used for any 
purpose or in any manner that would constitute a violation of any Applicable 
Laws.  The receiving party will not reproduce the Confidential Information of 
the disclosing party in any form other than to the extent required to enable 
the receiving party to satisfy its obligations under this Agreement.  The 
receiving party will use at least the same standard of care to protect 
Confidential Information of the disclosing party as it uses to protect 
proprietary or confidential information of its own. The receiving party will 
promptly notify the disclosing party upon discovery of any unauthorized use 
or disclosure of the Confidential Information of the disclosing party.  All 
information that is to be held confidential shall be given only to employees 
of the receiving party who are made aware of the confidential nature of the 
information and who have an obligation to maintain the confidentiality of the 
information under a signed confidentiality agreement or employment agreement 
or who have a fiduciary responsibility to the receiving party and who have a 
bona-fide need to know.

9.2       EXCEPTIONS.  Confidential Information shall not include any 
information that the receiving party can document:

          (a)  was in its possession or known by it prior to receipt from the 
disclosing party;

          (b)  is or (through no fault of the receiving party) becomes 
generally available to the public;

          (c)  is rightfully disclosed to the receiving party by a Third 
Party having no obligations of confidentiality to the disclosing party, 
provided the receiving party complies with any restrictions imposed by the 
Third Party; or

          (d)  was independently developed by employees or consultants of the 
receiving party without access to any Confidential Information of the 
disclosing party.

9.3       AUTHORIZED DISCLOSURE.  Notwithstanding any other provision of this 
Agreement, each party may disclose Confidential Information if such 
disclosure:

          (a)  is required by law or regulation (including, without 
limitation, in connection with filings with the United States Securities and 
Exchange Commission), provided that the receiving party uses reasonable 
efforts to restrict disclosure and, in the course of regulatory disclosures, 
to obtain confidential treatment therefor in accordance with customary 
practices;

                                      -27-
<PAGE>

          (b)  is in response to a valid order of a court or other 
governmental body of the United States or any country in the Territory or of 
any political subdivision thereof; provided, however, that the receiving 
party shall first have given notice to the disclosing party and shall have 
made a reasonable effort to obtain a protective or other appropriate form of 
order requiring that the Confidential Information so disclosed be used only 
for the purposes for which the order was issued;

          (c)  is otherwise required by Applicable Laws;

          (d)  is otherwise necessary to file or prosecute patent 
applications, prosecute or defend litigation or comply with Applicable Laws 
or otherwise establish rights or enforce obligations under this Agreement, 
but only to the extent that any such disclosure is necessary; or

          (e)  is required by authorities, investigators or Institutional 
Review Boards in conjunction with performing clinical development programs, 
provided that the receiving party shall use reasonable efforts to restrict 
disclosure and to cause such authorities, investigators or Institutional 
Review Boards not to disclose the Confidential Information to any Third Party.

9.4       INJUNCTIVE RELIEF.  Each party acknowledges and agrees that due to 
the unique nature of the other's Confidential Information, there can be no 
adequate remedy at law for any breach of its obligations under Article 9 of 
this Agreement and, therefore, that upon any such breach or threat thereof, 
the other party shall be entitled, notwithstanding anything to the contrary 
in Article 15, to injunctive relief and other appropriate equitable relief in 
addition to whatever remedies it may have at law from any court of competent 
jurisdiction in any jurisdiction authorized to grant the relief necessary to 
prohibit the breach or threatened breach.

                                  ARTICLE 10
                            INTELLECTUAL PROPERTY

10.1      OWNERSHIP OF INTELLECTUAL PROPERTY.  Except to the extent licensed 
to Chugai pursuant to Section 2.1(a) above, MBI shall retain all of its 
rights, title and interest in and to (i) all MBI Technology, MBI Patents, and 
MBI Improvements and (ii) all trademarks licensed to Chugai pursuant to 
Section 4.2(c).  Except to the extent licensed to MBI pursuant to Sections 
2.1(b) above, Chugai shall retain all of its rights, title and interest in 
and to all Chugai Technology, Chugai Patents, and Chugai Improvements.

10.2      VALIDITY AND INFRINGEMENT OF MBI PATENTS AND CHUGAI PATENTS.

          (a)  In the event MBI or Chugai becomes aware of any actual or 
threatened infringement of any MBI Patents or any Chugai Patents in the 
Territory, that party shall promptly notify the other.

          (b)  MBI shall have the sole right, but not the obligation, after
consulting with Chugai, to bring and control any infringement action against any
person or entity infringing the MBI Patents directly or contributorily and to
defend the MBI Patents against any challenge to the

                                     -28-

<PAGE>

validity and enforceability of the MBI Patents in the appropriate courts or 
agencies outside the Territory.

          (c)  Each party shall promptly notify the other in writing of any 
infringement or suspected infringement of any of the MBI Patents or the 
Chugai Patents in the Territory.  MBI shall, after consulting with Chugai, 
have the first right, but not the obligation, to bring and control any 
infringement action against any person or entity infringing the MBI Patents 
in the Territory and Chugai shall, after consulting with MBI, have the first 
right, but not the obligation, to bring and control any infringement action 
against any person or entity infringing the Chugai Patents in the Territory.  
In the event that MBI elects not to bring any infringement action against any 
person or entity infringing the MBI Patents in the Territory within   ***   
after receiving written notice from Chugai of the infringement or suspected 
infringement, Chugai shall have the right to bring and control such action.  
In the event that Chugai elects not to bring any infringement action against 
any person or entity infringing the Chugai Patents in the Territory within   
***   after receiving written notice from MBI of the infringement or 
suspected infringement, MBI shall have the right to bring and control such 
action.  Each party shall notify the other party in writing (the "Action 
Notice") in the event the party initiates an action for infringement of the 
MBI Patents or the Chugai Patents in the Territory as permitted by this 
Section 10.2(c).  The other party shall reasonably cooperate with the 
initiating party, as reasonably requested, in the prosecution of the 
infringement action and shall have a period of   ***   from the date of the 
Action Notice to elect to participate in the infringement action.  If the 
other party so elects in writing, it shall pay   ***   of the costs and 
expenses incurred by the party initiating the infringement action in 
prosecuting the infringement action (which payment shall be made as the costs 
and expenses are incurred within thirty (30) days after receipt of an invoice 
from the party initiating the infringement action), and it shall receive   
***   of all damages or other monetary awards recovered in the action 
(including any amounts received in settlement).  Notwithstanding the election 
of the other party to participate in the infringement action, each party 
shall have the sole right to enter into a settlement or consent judgment or 
other voluntary final disposition of any infringement action relating to its 
patents without the consent of the other party.  In the event the other party 
does not notify the party initiating the infringement action in writing of 
its election to participate in the action within   ***   after the date of 
the Action Notice or gives the other party written notice of its intent not 
to participate in the infringement action prior to the end of such   ***   
period, the party initiating the infringement action shall pay all of the 
costs and expenses incurred in prosecuting the infringement action and shall 
keep all damages or other monetary awards recovered in the action (including 
any amounts received in settlement).

10.3      INFRINGEMENT OF THIRD PARTY PATENTS.  

          (a)  If a Third Party asserts that a patent or other proprietary 
right owned by it is infringed by the manufacture, use or sale of any 
Licensed Product in the Territory, the party against whom the claim is 
asserted shall immediately provide the other party notice of the claim and 
the related facts in reasonable detail.   ***   shall control the defense of 
all such claims in the Territory, and   ***   shall provide reasonable 
assistance to   ***    in the defense of all such claims.   ***   shall also 
have the right to control the settlement of such claims; provided, however, 
that no settlement shall be entered into   ***.

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<PAGE>

All settlements approved by   ***   and the reasonable expenses of the 
litigation resolved by the settlement, and all final, non-appealable 
judgments and the reasonable expenses of the litigation that results in the 
final, non-appealable judgment, shall be paid as follows:  (i) except as 
provided in clause (ii) below, (a)   ***   of such reasonable expenses, 
settlements, and judgments (including any royalties owing pursuant to any 
settlement or judgment) to the extent that they relate to   ***, and (b)   
***   shall pay   ***   such expenses, settlements and judgments (including 
any royalties owing pursuant to any settlement or judgment) to the extent 
that they relate to   ***   and (ii)   ***   shall pay   ***   such expenses, 
settlements, and judgments (including any royalties owing pursuant to any 
settlement or judgment) to the extent that they relate to   ***.  If MBI 
determines that a Licensed Product potentially infringes on the intellectual 
property rights of a Third Party in the Territory, then upon MBI's written 
request and until Chugai's receipt of further written notice from MBI, Chugai 
shall cease all sales and distribution of such Licensed Product.  In 
addition, in the event Chugai determines that a Licensed Product potentially 
infringes on the intellectual property rights of a Third Party in the 
Territory, Chugai shall have the right to cease all sales and distribution of 
such Licensed Product.

          (b)  Each party shall immediately notify the other party in the 
event it becomes aware of both (i) a claim by any Third Party that a patent 
or other proprietary right owned by the Third Party is infringed by the 
manufacture, use or sale of any Licensed Product outside the Territory and 
(ii)   ***   shall control the defense of all such claims, and   ***   shall 
provide reasonable assistance to   ***   in the defense of all such claims.   
***   shall also have the right to control the settlement of such claims; 
provided, however, that no settlement of such claims shall be entered into   
***   shall pay   ***   reasonable expenses, settlements and judgments 
(including any royalties owing pursuant to any settlement or judgment) 
arising from such litigation.

          (c)   ***.  If Chugai is prohibited by court order from developing, 
manufacturing, or marketing any of the Licensed Products in the Territory   
***   MBI and Chugai shall hold an Executive Committee meeting within ten 
(10) days after Chugai has stopped developing, manufacturing, or marketing 
any of the Licensed Products and the Executive Committee shall discuss 
potential future actions with respect to the   ***.  If Chugai is required by 
court order to stop developing,









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                                     -30-

<PAGE>

manufacturing, marketing or selling any Licensed Product   ***. 
Notwithstanding the forgoing, Chugai shall not be relieved from paying 
milestone payments under Section 5.2 or royalties under Section 5.3 with 
respect to development activities conducted or Net Sales made before or after 
the period during which Chugai ceases development, manufacturing, marketing 
or sales activities as a result of such court order.

10.4      RESPONSIBILITY FOR PATENTS AND TRADEMARKS.
      
       (a)     MBI shall, at its own cost and expense, file and prosecute 
patent, copyright and trademark applications and maintain patents, copyrights 
and trademarks relating to the MBI Technology and the MBI Improvements in the 
Territory.  Chugai shall, at its own cost and expense, file and prosecute 
patent, copyright and trademark applications and maintain patents, copyrights 
and trademarks relating to the Chugai Technology, the Chugai Improvements and 
any trademarks selected by Chugai for the Licensed Products in the Territory. 
Each party will consult the other party with respect to, and will keep that 
party promptly informed of, all material developments relating to the 
preparation, filing, prosecution and maintenance of patents and patent 
applications covered by this Agreement.  Each party shall endeavor in good 
faith to coordinate its efforts with those of the other party to minimize or 
avoid interference with the prosecution of the other party's patent 
applications.

          (b)  MBI shall, at its own cost and expense, maintain during the 
term granted and seek extensions of the term of the MBI Patents and patents 
relating to MBI Improvements in the Territory.  Chugai shall, at its own cost 
and expense, maintain during the term granted and seek extensions of the term 
of the Chugai Patents and patents relating to Chugai Improvements in the 
Territory.  

          (c)  Each party initially responsible for preparation, filing, 
prosecution and maintenance of a particular patent or patent application (the 
"Initial Responsible Party") shall give thirty (30) days advance notice (the 
"Discontinuance Election") to the other party of any intention or decision to 
cease preparation, filing, prosecution or maintenance of any patent or patent 
application relating to its technology (a "Discontinued Patent"); provided, 
however, that abandonment of a patent application in favor of a continuation 
or continuation-in-part thereof shall not constitute discontinuance of the 
parent application.  In such case, the other party may elect at its sole 
discretion to continue preparation, filing, prosecution or maintenance of the 
Discontinued Patent at its sole expense, subject to the prior rights of Third 
Parties.  The party so continuing shall own any such patent or patent 
application and patents maturing therefrom, subject to the prior rights of 
Third Parties, and the Initial Responsible Party shall execute such documents 
and perform such acts as may be reasonably necessary for the other party to 
file or to continue to prosecute or maintain any such patent or patent 
applications, including assigning ownership of such patents and patent 
applications to the party electing to continue.  Discontinuance may be on a 
country-by-country basis or for a patent application or patent series in 
total.




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<PAGE>

    (d)    MBI shall provide to Chugai reasonable material information in 
MBI's possession that will help Chugai register the license of all patents 
that are exclusively licensed to Chugai pursuant to this Agreement with the 
Japanese Patent Office.  All costs and expenses of any such registration 
shall be paid by Chugai.  

                                  ARTICLE 11
                      TERM AND TERMINATION OF AGREEMENT

11.1      TERM.  Unless sooner terminated as otherwise provided in this 
Agreement, the term of this Agreement will commence on the Effective Date and 
continue for a period of fifteen (15) years from the Effective Date.  If 
requested by either party in writing no later than   ***   prior to the end 
of the term of the Agreement, both parties will discuss a potential extension 
of the term of the Agreement, provided that neither party shall have any 
liability hereunder in the event the parties are not able to agree on an 
extension of the term of this Agreement.  

11.2      EFFECT OF FAILURE TO CONDUCT OBLIGATIONS.

          (a)  In the event Chugai fails to meet any of its development 
obligations set forth in Sections 3.3 or any of its marketing or distribution 
obligations set forth in Section 4.1 in any country in the Territory with 
respect to any Licensed Product, or in the event that Chugai fails to meet 
its development obligation set forth in Section 3.4 with respect to FS069 in 
Japan, then in addition to any other rights it may have under this Agreement, 
MBI shall have the option to convert Chugai's exclusive rights under this 
Agreement to nonexclusive rights in such country with respect to such 
Licensed Product.

          (b)  Prior to exercising any rights under this Section 11.2, MBI 
shall give Chugai thirty (30) days' notice and shall meet with Chugai, at 
Chugai's request and expense, during such thirty (30) day period, to discuss 
any disagreements about whether Chugai has satisfied its development 
obligations under Section 3.3 or 3.4 or its marketing and distribution 
obligations under Section 4.1.  Upon expiration of such thirty (30) day 
period, MBI shall have the right in its sole discretion to convert Chugai's 
exclusive rights under this Agreement to nonexclusive rights in such country 
with respect to such Licensed Product unless Chugai satisfies the applicable 
development or marketing and distribution obligation during such thirty (30) 
day period.

          (c)  In the event that both:

                (A) either (i)   ***   contained in the patents issued or     
          published under the numbers   ***, or (ii) ***  contained in the 
          patents issued or published under the  numbers  ***, respectively, 
          or no patents issue in   ***   based on the  patent claims contained 
          in the   ***   filed  under the application number   ***, or 
          (iii)   ***   contained in the patents issued or published under 
          the numbers

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<PAGE>

     ***  respectively, and no other patents are issued with respect to  ***  
     or (iv)  ***  contained in the patents issued or published under the 
     numbers  ***  , respectively, or no patents issue in  *** based on the 
     patent claims contained in the  ***  filed under the application number  
     ***  , and no other patents are issued with respect to  ***  or (v)  *** 
     contained in the patent published under the number ***  are determined 
     to be invalid by the patent authority in  *** , and 

          (B) Chugai suffers a material loss in sales of a Licensed Product 
     in Japan, Korea or Taiwan as a result of both (i)  ***  for such 
     Licensed Product in such country (and, in the case of   ***  ) and (ii) 
     the introduction of one or more products by Third Parties in such 
     country that would have been precluded had the  ***  (and , in the case 
     of  ***  ,

then Chugai shall be permitted to elect one (but not both) of the following 
remedies:  either (i) the royalty owing to MBI pursuant to Section 5.3 for 
sales of the Licensed Product   ***  (and, in the case of  ***  ) shall be 
reduced in an amount agreed upon by MBI and Chugai, or (ii) Chugai shall be 
permitted to terminate this Agreement with respect to the Licensed Product  
***  (and, in the case of   ***  ).  Chugai shall only be entitled to receive 
a royalty reduction or to terminate this Agreement in the country or 
countries in which  ***  (and, in the case of  ***    ), and the royalty 
shall not be reduced, nor shall Chugai have any right to terminate this 
Agreement pursuant to this Section 11.2(c), in any other countries in the 
Territory or with respect to any other Licensed Products. Chugai shall 
exercise its election under  this Section 11.2(c) be delivering written 
notice to MBI at least  ***  prior to the effective date of Chugai's 
election.  If MBI disputes Chugai's right to exercise its election under this 
Section 11.2(c), the parties shall meet in good faith to discuss the dispute. 
 If MBI and Chugai cannot agree on the amount of such royalty reduction, the 
matter will be arbitrated pursuant to the provisions of Section 15.1.  The 
arbitrator will be instructed to resolve the dispute based on ***  .  In 
addition, in the event that Chugai elects pursuant to this Section 11.2(c) to 
terminate this Agreement with respect to any Licensed Product in any country 
in the Territory, Chugai shall not at any time thereafter (whether 

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<PAGE>

during or after the Term) manufacture, market, sell or distribute, either 
directly or through any Affiliate or Third Party, nor shall Chugai grant any 
rights (whether by license, transfer or otherwise) to any Affiliate or Third 
Party to manufacture, market, sell or distribute, *** .

11.3      TERMINATION FOR DEFAULT.  If either party is in material default of 
any of its obligations under this Agreement and (i) fails to remedy the 
default within  ***  after receipt of written notice  ***  in the case of 
nonpayment) from the other party detailing the substance of the default or 
(ii) in the event the default is not capable of cure within such  ***  
period, fails to commence to cure the default within such period and 
thereafter to prosecute such cure diligently to completion (but in no event 
shall the period for such cure be greater than  ***  after the receipt of the 
written notice of the default) the other party may terminate this Agreement 
with immediate effect by written notice. 

11.4      EFFECT OF TERMINATION.

          (a)  TERMINATION BY MBI.  In the event that MBI terminates this 
Agreement as a result of Chugai's material breach pursuant to Section 11.3, 
then:

               (i)  All licenses granted to Chugai pursuant to Section 
          2.1.(a) and Section 4.2(c) shall terminate immediately, and Chugai, 
          its Affiliates, sublicensees and distributors shall have no further 
          rights in the MBI Technology, the MBI Patents, the MBI Improvements 
          or the trademarks owned by or licensed to MBI. 

              (ii)  Chugai shall immediately transfer to MBI, at MBI's 
          request, all rights to all trademarks owned or in-licensed by 
          Chugai or its Affiliates, sublicensees or distributors under which 
          the Licensed Products are sold in the Territory and Chugai shall 
          not, either directly or indirectly, use or permit the use of the 
          trademarks owned by MBI or the trademarks owned or in-licensed by 
          Chugai or its Affiliates, sublicensees or distributors under which 
          the Licensed Products are sold in the Territory or of the 
          promotional procedures, methods or documentation relating to the 
          Licensed Products.

              (iii)  Chugai shall promptly return or destroy, at MBI's 
          direction and at Chugai's expense, all data, writings and other 
          documents and tangible materials supplied to Chugai by MBI during 
          the term of this Agreement.

               (iv)  Chugai shall promptly provide to MBI, as reasonably 
          requested by MBI and at Chugai's expense, full and complete copies 
          of all toxicity, efficacy, and other data generated by Chugai or 
          its Affiliates, sublicensees or distributors in the course of 
          Chugai's efforts to develop the Licensed Products or to obtain 
          Marketing Authorizations for the Licensed Products, including but 
          not limited to any IND, NDA or other documents filed with any 
          Competent Authority in the Territory.  Chugai shall also cooperate, 
          at its own expense and as reasonably requested by MBI, with any 
          Third Parties selected by MBI to distribute, market or sell the 
          Licensed Product in the Territory following the termination of the 
          Agreement by MBI pursuant to Section 11.3.  Such cooperation shall 
          include, but 

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<PAGE>

      shall not be limited to, *** .

               (v)  Chugai shall transfer immediately to MBI, to the extent 
      permitted by Applicable Laws, without consideration, any Marketing 
      Authorizations held by Chugai and Chugai will also cause any Marketing 
      Authorizations held by its Affiliates, sublicensees or distributors to 
      be transferred immediately to MBI, to the extent permitted by 
      Applicable Laws.  Chugai will fully cooperate at its own cost with MBI 
      and all Competent Authorities and do all things and acts necessary to 
      cause both the legal and equitable ownership of the Marketing 
      Authorizations to vest in MBI or its designees immediately after 
      termination of the Agreement by MBI pursuant to Section 11.3, including 
      without limitation granting (and causing each of its Affiliates, 
      sublicensees and distributors to grant) a perpetual, exclusive, 
      royalty-free license to MBI to use all rights under any Marketing 
      Authorizations that cannot be transferred to MBI under Applicable Laws. 
      MBI and any Third Parties selected by MBI to distribute, market or sell 
      the Licensed Product in the Territory following termination of the 
      Agreement by MBI pursuant to Section 11.3 shall also be authorized to 
      cross-reference any such Marketing Authorizations held by Chugai, its 
      Affiliates, sublicensees or distributors with respect to the Licensed 
      Product where permitted by Applicable Laws.

Termination of this Agreement by MBI pursuant to this Section 11.4(a) shall not
prohibit MBI from exercising any other remedies it may have as a result of
Chugai's material breach of this Agreement.

          (b)  TERMINATION BY CHUGAI.  In the event that Chugai terminates this
Agreement as a result of MBI's material breach pursuant to Section 11.3, then:

               (i)  All licenses granted to Chugai pursuant to Section 
      2.1.(a) and Section 4.2(c) shall terminate immediately, and Chugai, its 
      Affiliates, sublicensees and distributors shall have no further rights 
      in the MBI Technology, the MBI Patents, the MBI Improvements or the 
      trademarks owned by MBI. 

              (ii)  Chugai shall not, either directly or indirectly, use or 
      permit the use of the trademarks owned by MBI or the trademarks owned 
      or in-licensed by Chugai or its Affiliates, sublicensees or 
      distributors under which the Licensed Products are sold in the 
      Territory or of the promotional procedures, methods or documentation 
      relating to the Licensed Products.

             (iii)  Chugai shall promptly return or destroy, at MBI's 
      direction and at MBI's expense, all data, writings and other documents 
      and tangible materials supplied to Chugai by MBI during the Term.

              (iv)  Upon mutually agreeable terms and conditions, Chugai 
      shall provide to MBI, as reasonably requested by MBI, full and complete 
      copies of all toxicity, efficacy, and other data generated by Chugai or 
      its Affiliates, sublicensees or distributors in the course of Chugai's 
      efforts to develop the Licensed Products or to obtain Marketing  


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<PAGE>

      Authorizations for the Licensed Products, including but not limited to 
      any IND, NDA or other documents filed with any Competent Authority in 
      the Territory.

               (v)  Upon mutually agreeable terms and conditions, Chugai 
      shall transfer (and shall cause its Affiliates, sublicensees and 
      distributors to transfer) (A) any trademarks owned or in-licensed by 
      Chugai or its Affiliates, sublicensees or distributors under which the 
      Licensed Product are sold in the Territory and (B) any Marketing 
      Authorizations held by Chugai or any of its Affiliates, sublicensees or 
      distributors, to the extent permitted by Applicable Laws.

               (vi) In the event that MBI desires to use any data, writings 
      or other documents or tangible material supplied by Chugai to MBI 
      during the Term, Chugai shall sell such data, writings, documents and 
      materials to MBI  ***  , as reasonably agreed by the parties.  
      In the event that MBI does not desire to use any such data, writings, 
      documents or materials, MBI shall promptly return or destroy such 
      items, at Chugai's direction.

Termination of this Agreement by Chugai pursuant to this Section 11.4(b) 
shall not prohibit Chugai from exercising any other remedies it may have as a 
result of MBI's material breach of this Agreement.

      (c)  DISCONTINUANCE OF DEVELOPMENT BY CHUGAI.  In the event that Chugai 
elects at any time to discontinue the Chugai Development Program with respect 
to any of the Licensed Products pursuant to Section 3.5 prior to obtaining 
any Marketing Authorization for such Licensed Product, then:

               (i)  All licenses granted to Chugai pursuant to Section 
      2.1.(a) and Section 4.2(c) with respect to the Licensed Product shall 
      terminate immediately, and Chugai, its Affiliates, sublicensees and 
      distributors shall have no further rights in the MBI Technology, the 
      MBI Patents, the MBI Improvements or the trademarks owned by MBI with 
      respect to the Licensed Product. 

              (ii)  Chugai shall not, either directly or indirectly, use or 
      permit the use of the trademarks owned by MBI or the trademarks owned 
      or in-licensed by Chugai or its Affiliates, sublicensees or 
      distributors under which the Licensed Products are sold in the 
      Territory or of the promotional procedures, methods or documentation 
      relating to the Licensed Product.

             (iii)  Chugai shall promptly return or destroy, at MBI's 
      direction and at MBI's expense, all data, writings and other documents 
      and tangible materials with respect to the Licensed Products supplied 
      to Chugai by MBI during the Term.

              (iv) Chugai shall promptly provide to MBI, as reasonably 
      requested by MBI and at a reasonable expense to Chugai, full and 
      complete copies of all toxicity, efficacy, and other data generated by 
      Chugai or its Affiliates, sublicensees or distributors in the course of 
      Chugai's efforts to develop the Licensed Product or to obtain Marketing 
      Authorizations 

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

                                       -36-

<PAGE>

      for the Licensed Product, including but not limited to any IND, NDA or 
      other documents filed with any Competent Authority in the Territory.  
      Chugai shall also cooperate, at MBI's expense and as reasonably 
      requested by MBI, with any Third Parties selected by MBI to distribute, 
      market or sell the Licensed Product in the Territory following the 
      termination of the Chugai Development Program with respect to the 
      Licensed Product.  Such cooperation shall include, but shall not be 
      limited to,  ***.

11.5     SURVIVING OBLIGATIONS.  Termination or expiration of this Agreement 
shall not relieve either party of its obligations under Sections 2.1(b), 5.7, 
6.2, 8.3, 8.8 and 8.10 and Articles 9, 10 (other than Section 10.2(a)), 11, 
12, 15 and 16.

                                    ARTICLE 12
                                    INDEMNITY

12.1      INDEMNIFICATION BY MBI.  MBI agrees to indemnify and hold Chugai 
and its officers, directors, employees and agents harmless from and against 
all claims, damages, losses, costs and expenses, including reasonable 
attorneys' fees (individually, a "Loss" and collectively, "Losses"), that 
Chugai may incur to the extent that such Losses arise out of or result from 
(i) any Licensed Product manufactured by MBI and supplied to Chugai pursuant 
to Section 7.1(b) to the extent that such Licensed Product causes or results 
in the injury, illness or death of any person, but only to the extent that 
such Losses arise out of or result from (a) a defect in the MBI Technology 
incorporated into the Licensed Product or (b) the negligence, recklessness or 
willful misconduct of MBI or its officers, employees or agents in connection 
with the manufacture of such Licensed Product, (ii) violation by MBI of the 
provisions of this Agreement, (iii) violation by MBI of any Applicable Laws, 
or (iv) breach of any representation made or warranty given by MBI in this 
Agreement, or (v) the manufacture, sale or use of any Licensed Product that 
is not supplied by Chugai and which is sold by MBI, its Affiliates, Licensees 
or distributors outside the Territory, but only to the extent that the Losses 
arise out of claims asserted against Chugai outside the Territory.  In 
addition, in the event that Chugai informs MBI that it believes any of the 
Licensees has damaged the value of any trademarks for the Licensed Products 
used by Chugai, MBI will work with Chugai in good faith in an effort to 
communicate Chugai's concerns to the Licensee.

12.2      INDEMNIFICATION BY CHUGAI.  Chugai agrees to indemnify and hold MBI 
and its officers, directors, employees and agents harmless from and against 
all Losses that MBI may incur to the extent that such Losses arise out of or 
result from (i) violation by Chugai of the provisions of this Agreement; (ii) 
violation by Chugai, its Affiliates sublicensees or distributors of any 
Applicable Laws; (iii) breach of any representation or warranty given by 
Chugai in this Agreement; and (iv) the manufacture, sale or use of any 
Licensed Product that is not supplied by MBI and which is  manufactured, 
marketed or sold by Chugai or its Affiliates, sublicensees or distributors, 
but only to the extent that the Losses arise out of claims asserted against 
MBI inside the Territory.

12.3      INDEMNIFICATION PROCEDURES.  The party seeking indemnification 
under this Article 12 (the "Indemnified Party") shall (i) give the other 
party (the "Indemnifying Party") notice of the relevant claim, (ii) cooperate 
with the Indemnifying Party, at the Indemnifying Party's expense, in the 
defense of such claim, and (iii) give the Indemnifying Party the right to 
control the defense 


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

                                      -37-

<PAGE>

and settlement of any such claim, except that the Indemnifying Party shall 
not enter into any settlement that affects the Indemnified Party's rights or 
interest without the Indemnified Party's prior written approval.  The 
Indemnified Party shall have no authority to settle any claim on behalf of 
the Indemnifying Party.

12.4      EXCLUSIONS.  MBI shall have no obligation of indemnity under this 
Article 12 for any claims related to any Licensed Products (i) which are 
modified other than by MBI or its agents, to the extent that the Loss relates 
to such modification, or (ii) which are combined with other products, 
processes or materials not provided by MBI, to the extent that the Loss 
relates to such combination.

12.5      LIMITED LIABILITY.  EXCEPT AS OTHERWISE PROVIDED BELOW IN THE LAST 
SENTENCE OF THIS SECTION 12.5 AND NOTWITHSTANDING ANYTHING ELSE IN THIS 
AGREEMENT OR OTHERWISE, NEITHER PARTY WILL BE LIABLE WITH RESPECT TO ANY 
SUBJECT MATTER OF THIS AGREEMENT UNDER ANY CONTRACT, NEGLIGENCE, STRICT 
LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR (I) ANY SPECIAL, INDIRECT, 
INCIDENTAL OR CONSEQUENTIAL DAMAGES OR (II) COST OF PROCUREMENT OF SUBSTITUTE 
GOODS, TECHNOLOGY OR SERVICES. THE LIMITATIONS OF THIS SECTION 12.5 SHALL NOT 
APPLY TO ANY CLAIMS FOR BREACH OF ARTICLE 9.

                                   ARTICLE 13
                        REPRESENTATIONS AND WARRANTIES

13.1      REPRESENTATION AND WARRANTIES OF MBI.  MBI hereby represents and 
warrants as follows:

          (a)  CORPORATE POWER.  MBI is duly organized and validly existing 
under the laws of the state of Delaware and has full corporate power and 
authority to enter into this Agreement and to carry out the provisions hereof.

          (b)  DUE AUTHORIZATION.  MBI is duly authorized to execute and 
deliver this Agreement and to perform its obligations hereunder.

          (c)  BINDING AGREEMENT.  This Agreement is a legal and valid 
obligation binding upon MBI and is enforceable in accordance with its terms.  
The execution, delivery and performance of this Agreement by MBI does not 
conflict with any agreement, instrument or understanding, oral or written, to 
which it is a party or by which it may be bound, nor violate any Applicable 
Laws of any court, governmental body or administrative or other agency having 
authority over it.

          (d)  DOCUMENTS FILED WITH FDA.  To the best of MBI's knowledge, the 
data presented to the FDA for review in connection with the approval of the 
New Drug Application for FS069 was obtained from the development of FS069 
conducted by MBI, its Affiliates or its agents and was not intentionally 
altered by MBI.

                                      -38-

<PAGE>



13.2      REPRESENTATIONS AND WARRANTIES OF CHUGAI.  Chugai hereby represents 
and warrants as follows:

          (a)  CORPORATE POWER.  Chugai is duly organized and validly existing 
under the laws of Japan and has full corporate power and authority under
Applicable Laws to enter into this Agreement and to carry out the provisions 
hereof.

          (b)  DUE AUTHORIZATION.  Chugai is duly authorized to execute and
deliver this Agreement and to perform its obligations hereunder.

          (c)  BINDING AGREEMENT.  This Agreement is a legal and valid 
obligation binding upon Chugai and is enforceable in accordance with its terms.
The execution, delivery and performance of this Agreement by Chugai does not
conflict with any agreement, instrument or understanding, oral or written, to
which it is a party or by which it may be bound, nor violate any Applicable Laws
of any court, governmental body or administrative or other agency having
authority over it.

          (d)  NO TRANSFERS OF MARKETING AUTHORIZATIONS.  Chugai will not
transfer, assign, mortgage nor charge any of the rights under the Marketing
Authorizations other than to MBI or to a person designated by MBI or to a Third
Party distributor appointed by Chugai to distribute the Licensed Products that 
has been approved by MBI and has entered into a written agreement as provided in
Section 8.3.  Chugai shall not intentionally do anything to adversely affect the
Marketing Authorizations. Chugai shall not knowingly do anything to prejudice
the ability of MBI or any entity designated by MBI to act as the holder of any
Marketing Authorization.

13.3      WARRANTY DISCLAIMER.  EXCEPT FOR SUCH REPRESENTATIONS AND WARRANTIES
AS ARE EXPRESSLY PROVIDED IN THIS AGREEMENT, NEITHER PARTY MAKES ANY OTHER
REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT
LIMITATION, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NON-INFRINGEMENT WITH RESPECT TO THE LICENSED PRODUCTS, ANY TECHNOLOGY OR ANY
PRODUCTS SUPPLIED OR SERVICES PERFORMED HEREUNDER.

                                      ARTICLE 14
                                      ASSIGNMENT

14.1      ASSIGNMENT.  Neither party shall assign its rights or delegate its 
duties under the Agreement without the prior written consent of the other; 
provided, however, that either party may assign this Agreement to any successor
by merger or sale of all or substantially all of its business.

14.2      BENEFITS AND BINDING NATURE OF AGREEMENT.  In the case of any 
permitted assignment of this Agreement pursuant to Section 14.1, this Agreement
shall be binding upon, and shall inure to the benefit of, the permitted assigns
of the parties hereto.


                                      -39-


<PAGE>


14.3      PROHIBITED ASSIGNMENT NULL AND VOID.  Any attempted assignment or
delegation in contravention of Section 14.1 shall be void and of no effect.

                                      ARTICLE 15
                                  DISPUTE RESOLUTION

15.1      ARBITRATION.  If a dispute arises from or relates to the 
interpretation, implementation or alleged breach of this Agreement, or with 
respect to any of the transactions or events contemplated hereby, the parties 
shall attempt in good faith to resolve the dispute within thirty (30) days by 
referring the dispute to one or more executive officers of each party.  If 
the dispute is not resolved by the executive officers within thirty (30) days 
after either party informs the other of the dispute in writing, the dispute 
shall be resolved by binding arbitration.  Each party shall give fifteen (15) 
days written notice to the other party prior to initiating any arbitration 
proceedings.  Any arbitration hereunder shall be conducted under the 
International Chamber of Commerce Arbitration Rules.  Each such arbitration 
shall be conducted in the English language by a panel of three arbitrators 
appointed in accordance with such rules.  Any such arbitration shall be held 
in   ***.  The arbitrators shall determine all issues regarding such dispute, 
including without limitation, procedure, discovery, arbitrability and waiver. 
 The arbitrators shall have the discretion to order a prehearing exchange of 
information by the parties, including, without limitation, production of 
requested documents, exchange of summaries of testimony by proposed witnesses 
and examination by deposition of parties.  The parties shall instruct the 
arbitrators to render their decision no later than ninety (90) days after 
submission of the dispute, which decision shall be in writing and shall 
specify the factual and legal bases for the award.  The arbitration of such 
issues, including the determination of any amount of damages suffered by any 
party hereto by reason of acts or omissions of the other party, shall be 
final and binding upon all parties.  The arbitrators shall have the authority 
to grant specific performance, and judgment on the arbitration award may be 
entered in any court having jurisdiction thereof.  Notwithstanding the 
foregoing, the arbitrator or arbitrators shall not be authorized toaward 
punitive damages with respect to any such claim or controversy, nor shall any 
party seek punitive damages relating to any matter under, arising out of or 
relating to this Agreement under any circumstances. Except as otherwise set 
forth in this Agreement, the cost of any arbitration hereunder, including the 
cost of the record or transcripts thereof, if any, administrative fees, and 
all other fees involved including reasonable attorneys' fees incurred by the 
party determined by the arbitrators to be the prevailing party, shall be paid 
by the party determined by the arbitrators not to be the prevailing party, or 
otherwise allocated in an equitable manner as determined by the arbitrators.

15.2      INJUNCTIVE RELIEF.  Notwithstanding any other provision of this 
Article 15 to the contrary, (i) any party shall be entitled to petition a court 
of competent jurisdiction for the specific, limited purpose of requesting
injunctive relief only in the event either party violates or attempts to violate
any of the covenants set forth in Article 9 hereof and (ii) MBI shall be
entitled to petition a court of competent jurisdiction for the specific, limited
purpose of requesting injunctive relief and other equitable remedies only in the
event of any breach or threatened breach by Chugai of the restrictions set forth
in Section 2.3 or 8.3.  Either party seeking injunctive relief in accordance
with the provisions of this Section 15.2 shall be entitled to petition a court
of competent jurisdiction in any jurisdiction authorized to grant the relief
necessary to prohibit the breach or


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



                                      -40-


<PAGE>

threatened breach for which the relief is sought.  This Section 15.2 shall 
not limit any other legal or equitable remedies (i) that either party may 
have against the other for breach of the covenants found in Article 9 or (ii) 
that MBI may have against Chugai for breach of the restrictions set forth in 
Section 2.3 or 8.3.  This Section 15.2 shall apply with equal force to 
Chugai's Affiliates, sublicensees and distributors, if any of them is the 
holder of the Marketing Authorization at the time the breach or threatened 
breach of Section 8.3 takes place.  The prevailing party shall be entitled to 
recover from the other party reasonable attorneys' fees and costs in 
connection with any such proceedings.

                                      ARTICLE 16
                                    MISCELLANEOUS

16.1      EXPORT LAW COMPLIANCE.  Chugai understands and recognizes that the 
Licensed Products and other materials made available to it hereunder may be 
subject to the export administration regulations of the United States 
Department of Commerce and other United States government regulations related 
to the export of drugs.  Chugai represents that it is familiar with and 
agrees to comply with all such regulations, including any future 
modifications thereof, in connection with the distribution of Licensed 
Products.  Chugai agrees that it will not export or reexport outside the 
Territory, directly or indirectly, any Licensed Product or clinical data 
relating to any License Product without the prior written consent of MBI and 
without complying with all Applicable Laws.  Chugai agrees to obtain the same 
agreement from each of its Affiliates, sublicensees and distributors. Chugai 
hereby agrees to indemnify and hold MBI harmless from any breach of this 
Section 16.1.

16.2      FOREIGN CORRUPT PRACTICES ACT.  Chugai hereby agrees that it shall 
comply with the requirements of the FCPA and shall refrain from any payments 
to Third Parties which would cause MBI or Chugai to violate the FCPA.  Chugai 
hereby agrees to indemnify and hold harmless MBI from any breach of this 
Section 16.2.

16.3      ENTIRE AGREEMENT.  This Agreement, the exhibits and schedules 
attached hereto or referenced herein, if any, and the Common Stock Purchase 
Agreement between the parties dated as of the date hereof together embody the 
final, complete and exclusive understanding between the parties relating to 
the subject matter hereof and thereof, and replace and supersede all 
proposals, oral and/or written, prior negotiations, representations, 
understandings and agreements between the parties relating to the subject 
matter hereof and thereof.

16.4      AMENDMENTS AND WAIVERS.  No modification or waiver of any term or 
condition of this Agreement shall be of any force or effect unless such 
modification or waiver is in writing and signed by an authorized officer of 
each party hereto. Any waiver by either party of any default or breach of 
this Agreement shall not constitute a waiver of any other or subsequent 
default or breach.

16.5      NO OTHER TERMS AND CONDITIONS.  The parties intend that this 
Agreement expresses all of the terms and conditions applicable to the sale of 
Licensed Products and accordingly agree that all provisions, terms and 
conditions of any purchase order, sales or order acknowledgment, invoice or 
other business form or document (a "Form"), unless an amendment to this 
Agreement


                                      -41-


<PAGE>


in accordance with Section 16.4 hereof, shall be superseded hereby and 
therefore shall be disregarded and have no force and effect.  If a Form 
purports to be conditioned in any manner on agreement to and/or acceptance of 
any provisions, terms and conditions other than those set forth herein, then 
such condition is hereby waived.  In no event shall either party be bound by 
any provisions, terms or conditions relating to the subject matter of this 
Agreement not set out herein.

16.6      FORCE MAJEURE.  Except with respect to a failure to perform any of 
its obligations under Section 3.4 or Section 11.3 of this Agreement, neither 
party shall be liable to the other for its failure to perform any of its 
obligations under this Agreement, except for payment obligations, during any 
period in which such performance is delayed because of, or rendered 
impracticable or impossible due to, a Force Majeure.  The party experiencing 
the failure or delay shall promptly notify the other party in writing of the 
failure or delay.

16.7      NOTICE.  All notices concerning this Agreement shall be written in 
the English language and shall be deemed to have been received (a) five (5) 
days after being properly sent by commercial overnight courier, or (b) two 
(2) days after being transmitted by confirmed facsimile, in each case 
addressed as follows:

               If to MBI:

                    Molecular Biosystems, Inc.
                    10030 Barnes Canyon Road
                    San Diego, California USA 92121-2789

                    Attention: Corporate Counsel

                    Telephone: (619) 824-2216
                    Facsimile: (619) 824-2395

               If To Chugai:

                    Chugai Pharmaceutical Co., Ltd.
                    2-1-9 Kyobashi, Chuo-ku
                    Tokyo 104-8301, Japan

                    Attention: Director, Legal Department

                    Telephone: 03-3273-0887
                    Facsimile: 03-3281-0315

16.8      ENGLISH LANGUAGE; GOVERNING LAW.  This Agreement has been prepared 
in the English language and the English language shall control its 
interpretation. This Agreement shall be governed by and construed in 
accordance with the internal laws of the  ***  without regard to its 
conflicts of laws principles. 


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


                                      -42-


<PAGE>


16.9      LATE PAYMENTS.  All amounts due and owing to a party under this 
Agreement that are not paid by the other party when due shall bear interest 
at the rate of  ***  per month or, if lower, the maximum rate allowed by law, 
in either case calculated from the date the amount was first due.

16.10     SEVERABILITY.  In the event that any provision of this Agreement 
shall be unenforceable or invalid under any applicable law or be so held by 
applicable court decision, such enforceability or invalidity shall not render 
this Agreement unenforceable or invalid as a whole, and, in such event, such 
provision shall be changed and interpreted so as to best accomplish the 
objectives of such unenforceable or invalid provision within the limits of 
applicable law or applicable court decisions.

16.11     RIGHTS AND REMEDIES CUMULATIVE.  Except as expressly provided 
herein, the rights and remedies provided in this Agreement shall be 
cumulative and not exclusive of any other rights and remedies provided by law 
or otherwise.

16.12     INDEPENDENT CONTRACTORS.  Each party shall act as an independent 
contractor under the terms of this Agreement.  Neither party is, nor shall it 
be deemed to be, an employee, agent, co-venturer, partner or legal 
representative of the other for any purpose.  Neither party shall be entitled 
to enter into any contracts in the name of, or on behalf of the other, nor 
shall either party be entitled to pledge the credit of the other in any way 
or hold itself out as having authority to do so.

16.13     CAPTIONS AND SECTION REFERENCES.  The section headings appearing in 
this Agreement are inserted only as a matter of convenience and in no way 
define, limit, construe or describe the scope or extent of such section or in 
any way affect such section.

16.14     REFERENCES TO DOLLARS.   All references to "dollars" or "$" in this 
Agreement are references to United States dollars unless reference is 
expressly made to the currency of another country. 

16.15     COUNTERPARTS.  This Agreement may be executed in counterparts with 
the same force and effect as if each of the signatories had executed the same 
instrument.

16.16     PRESS RELEASES.  The parties agree that the terms of this Agreement
shall be considered Confidential Information of both parties.  However, each
party shall have the right to disclose the terms of this Agreement to any
potential acquiror, merger partner or other bona fide potential financial
partner (which disclosure shall, however, be subject to the terms of a
nondisclosure agreement with the potential acquiror, merger partner or financial
partner), or if counsel to such party advises such party that it is proper to
make such disclosure to comply with rules and regulations of the United States
Securities and Exchange Commission, to satisfy Generally  Accepted Accounting
Principles or for other legal reasons.  Notwithstanding the foregoing, the
parties agree that the initial press releases regarding this Agreement shall be
mutually agreed by the parties.


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


                                      -43-


<PAGE>


          IN WITNESS WHEREOF, the parties have each caused this Agreement to 
be signed and delivered by their duly authorized representatives as of the 
date first written above.  

                               MOLECULAR BIOSYSTEMS, INC.



                               BY: /S/ B. VENKATADRI     
                                   ------------------------ 
                                   BOBBA VENKATADRI

                               TITLE: PRESIDENT AND CEO           
                                      ---------------------

                               CHUGAI PHARMACEUTICAL CO. LTD.



                               BY: /S/ ILLEGIBLE         
                                   ------------------------
                               TITLE: EXECUTIVE DIRECTOR, ACCOUNTING DEPARTMENT














                  [SIGNATURE PAGE TO COOPERATIVE DEVELOPMENT
                               AND MARKETING AGREEMENT]


                                      -44-


<PAGE>


EXHIBIT 1.23 

FS069
                                          
                                        ***














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

                              Exhibit 1.23-1


<PAGE>

PATENTS:


<TABLE>
<CAPTION>

              

     MBI         COUNTRY OR               STATUS             APPLICATION       APPLICATION      PATENT NUMBER        ISSUE DATE
  REFERENCE        REGION                                       NUMBER            DATE           (PUBLICATION       (PUBLICATION
    NUMBER                                                                                         NUMBER)              DATE)
- --------------------------------------------------------------------------------------------------------------------------------
         

<S>           <C>                <C>                       <C>               <C>             <C>                  <C>             
 ALB-1-JP1    JAPAN              ISSUED                    59-501032         01/26/84        1 598 465            01/28/91
                                                           [21]              [22]
                                 (TERM EXTENSION GRANTED)

 ALB-1-JP2    JAPAN              ISSUED                    61-289108         12/05/86        1 677 653            07/13/92

 ALB-2-JP1    JAPAN              PUBLISHED / OPPOSED       63-323826         12/23/88        (06-62445)           (08/17/94)

 ALB-2-KR1    KOREA              ISSUED                    17665/88          12/28/88        106 494              10/22/96

 ALB-2-TW1    TAIWAN             ISSUED                    77 109 129        12/29/88        037 100              6/15/90

 ALB-4-JP1    JAPAN              ISSUED                    01-237390         09/12/89        1 988 539            11/08/95

 ALB-4-KR1    KOREA              ALLOWED                   13246/89          09/12/89
                                                                              
 ALB-4-TW1    TAIWAN             ISSUED                    78 106 958        09/08/89        152 186              02/21/91    [44]

 AGM-1-JP1    JAPAN              PUBLISHED                 07-503679         07/01/94        (08-509002)          (09/24/96)   
                                                           [21]                               [11]                [43]

 AGM-1-KR1    KOREA              PENDING                   96-700002         07/01/94

 AGM-1-TW1    TAIWAN             ISSUED                    83 107 084        08/01/94        080 177              12/11/96
                                                           [21]              [22]
</TABLE>


***














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

                                 Exhibit 1.23-2


<PAGE>


EXHIBIT 1.34
MBI PATENTS

<TABLE>
<CAPTION>

     MBI         COUNTRY OR               STATUS             APPLICATION       APPLICATION      PATENT NUMBER        ISSUE DATE
  REFERENCE        REGION                                       NUMBER            DATE           (PUBLICATION       (PUBLICATION
    NUMBER                                                                                         NUMBER)              DATE)
- --------------------------------------------------------------------------------------------------------------------------------
<S>           <C>                <C>                       <C>               <C>             <C>                  <C>          
 ALB-1-JP1    JAPAN              ISSUED                    59-501032         01/26/84        1 598 465            01/28/91
                                                           [21]              [22]
                                 (TERM EXTENSION GRANTED)

 ALB-1-JP2    JAPAN              ISSUED                    61-289108         12/05/86        1 677 653            07/13/92

 ALB-2-JP1    JAPAN              PUBLISHED / OPPOSED       63-323826         12/23/88        (06-62445)           (08/17/94)

 ALB-2-KR1    KOREA              ISSUED                    17665/88          12/28/88        106 494              10/22/96

 ALB-2-TW1    TAIWAN             ISSUED                    77 109 129        12/29/88        037 100              6/15/90

 ALB-4-JP1    JAPAN              ISSUED                    01-237390         09/12/89        1 988 539            11/08/95

 ALB-4-KR1    KOREA              ALLOWED                   13246/89          09/12/89
                                                                              
 ALB-4-TW1    TAIWAN             ISSUED                    78 106 958        09/08/89        152 186              02/21/91    [44]

 AGM-1-JP1    JAPAN              PUBLISHED                 07-503679         07/01/94        (08-509002)          (09/24/96)   
                                                           [21]                                  [11]             [43]

 AGM-1-KR1    KOREA              PENDING                   96-700002         07/01/94
 

 AGM-1-TW1    TAIWAN             ISSUED                    83 107 084        08/01/94        080 177              12/11/96
                                                           [21]              [22]

 NEG-2-JP1    JAPAN              PUBLISHED                 07-509877         09/19/94        (08-511033)          (11/19/96)   
                                                           [21]              [22]                [11]             [43]
</TABLE>














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

                              Exhibit 1.34-1


<PAGE>


EXHIBIT 1.40
ORALEX-Registered Trademark-
***














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

                              Exhibit 1.40-1


<PAGE>


PATENT:

<TABLE>
<CAPTION>

     MBI         COUNTRY OR               STATUS             APPLICATION       APPLICATION      PATENT NUMBER        ISSUE DATE
  REFERENCE        REGION                                       NUMBER            DATE           (PUBLICATION       (PUBLICATION
    NUMBER                                                                                         NUMBER)              DATE)
- --------------------------------------------------------------------------------------------------------------------------------
 <S>               <C>                   <C>                   <C>               <C>             <C>                 <C>         
 NEG-2-JP1         JAPAN                 PUBLISHED             07-509877         09/19/94        (08-511033)         (11/19/96)   
                                                               [21]              [22]            [11]                [43]
</TABLE>

***














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

                              Exhibit 1.40-2


<PAGE>


EXHIBIT 1.45

***















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


                              Exhibit 1.45-1

<PAGE>


EXHIBIT 3.6(a)
MBI ORALEX-Registered Trademark- AND FS069 DEVELOPMENT PROGRAM

***














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

                              Exhibit 3.6(a)-1



<PAGE>

                                                      EXHIBIT 2.2 













                           -------------------------------
                              MOLECULAR BIOSYSTEMS, INC.

                           COMMON STOCK PURCHASE AGREEMENT

                                    March 31, 1998
                           -------------------------------


<PAGE>




 
                              TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                        PAGE

<S>                                                                        <C>
Section 1 Authorization and Sale of Common Stock . . . . . . . . . . . .   1
     1.1  Authorization. . . . . . . . . . . . . . . . . . . . . . . . .   1
     1.2  Sale of Common . . . . . . . . . . . . . . . . . . . . . . . .   1

Section 2 Closing Date; Delivery . . . . . . . . . . . . . . . . . . . .   1
     2.1  Closing Date . . . . . . . . . . . . . . . . . . . . . . . . .   1
     2.2  Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . .   1

Section 3 Representations and Warranties of the Company. . . . . . . . .   2
     3.1  Organization and Standing. . . . . . . . . . . . . . . . . . .   2
     3.2  Corporate Power; Authorization . . . . . . . . . . . . . . . .   2
     3.3  Issuance and Delivery of the Shares. . . . . . . . . . . . . .   2
     3.4  Governmental Consents. . . . . . . . . . . . . . . . . . . . .   2
     3.5  SEC Documents; Financial Statements. . . . . . . . . . . . . .   2
     3.6  No Material Adverse Change . . . . . . . . . . . . . . . . . .   3

Section 4 Representations, Warranties and Covenants of the Purchaser. . .  3
     4.1  Authorization. . . . . . . . . . . . . . . . . . . . . . . . .   3
     4.2  Investment Experience. . . . . . . . . . . . . . . . . . . . .   3
     4.3  Investment Intent. . . . . . . . . . . . . . . . . . . . . . .   3
     4.4  Registration or Exemption Requirements . . . . . . . . . . . .   4
     4.5  Restriction on Short Sales . . . . . . . . . . . . . . . . . .   4
     4.6  No Legal, Tax or Investment Advice . . . . . . . . . . . . . .   4
     4.7  Legends. . . . . . . . . . . . . . . . . . . . . . . . . . . .   4

Section 5 Conditions to Closing of Purchaser . . . . . . . . . . . . . .   5
     5.1  Representations and Warranties . . . . . . . . . . . . . . . .   5
     5.2  Performance. . . . . . . . . . . . . . . . . . . . . . . . . .   5
     5.3  Qualifications . . . . . . . . . . . . . . . . . . . . . . . .   5
     5.4  Compliance Certificate . . . . . . . . . . . . . . . . . . . .   5

Section 6 Conditions to Closing of Company . . . . . . . . . . . . . . .   5
     6.1  Representations and Warranties . . . . . . . . . . . . . . . .   5
     6.2  Covenants. . . . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.3  Qualifications . . . . . . . . . . . . . . . . . . . . . . . .   5
     6.4  Compliance Certificate . . . . . . . . . . . . . . . . . . . .   6

Section 7 Additional Covenants . . . . . . . . . . . . . . . . . . . . .   6
     7.1  Standstill Provisions. . . . . . . . . . . . . . . . . . . . .   6
     7.2  Market Stand-off . . . . . . . . . . . . . . . . . . . . . . .   6

</TABLE>

                                      -i-


<PAGE>

                              TABLE OF CONTENTS
                                 (CONTINUED)

<TABLE>
<CAPTION>
                                                                        PAGE

<S>                                                                        <C>
Section 8 Restrictions on Transferability of Shares:Compliance with
            Securities Act . . . . . . . . . . . . . . . . . . . . . . .   6
     8.1  Restrictions on Transferability. . . . . . . . . . . . . . . .   6
     8.2  Transfer of Shares After Registration. . . . . . . . . . . . .   7

Section 9 Miscellaneous. . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.1  Amendments and Waivers . . . . . . . . . . . . . . . . . . . .   7
     9.2  Governing Law. . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.3  Survival . . . . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.4  Successors and Assigns . . . . . . . . . . . . . . . . . . . .   7
     9.5  Entire Agreement . . . . . . . . . . . . . . . . . . . . . . .   7
     9.6  Notices, etc . . . . . . . . . . . . . . . . . . . . . . . . .   7
     9.7  Severability of this Agreement . . . . . . . . . . . . . . . .   8
     9.8  Counterparts . . . . . . . . . . . . . . . . . . . . . . . . .   8
     9.9  Further Assurances . . . . . . . . . . . . . . . . . . . . . .   8
     9.10 Termination. . . . . . . . . . . . . . . . . . . . . . . . . .   8
     9.11 Expenses . . . . . . . . . . . . . . . . . . . . . . . . . . .   8
     9.12 Currency . . . . . . . . . . . . . . . . . . . . . . . . . . .   9
</TABLE>

Exhibit A -- Instruction Sheet for Purchaser
Exhibit B -- Form of Stock Certificate Questionnaire/Purchaser Certificate
Exhibit C -- Form of Purchaser's Certificate of Subsequent Sale


                                      -ii-

<PAGE>


                        MOLECULAR BIOSYSTEMS, INC.

                     COMMON STOCK PURCHASE AGREEMENT



          This Common Stock Purchase Agreement (the "Agreement") is made as of
March 31, 1998, by and among Molecular Biosystems, Inc., a Delaware corporation
(the "Company"), with its principal office at 10030 Barnes Canyon Road, San
Diego, California USA 92121-2789, and Chugai Pharmaceutical Co., Ltd., a
Japanese corporation (the "Purchaser") with its principal office at 2-1-9,
Kyobashi, Chuo-ku, Tokyo 104-8301, Japan.


                                Section 1
 
                 AUTHORIZATION AND SALE OF COMMON STOCK

          1.1  AUTHORIZATION.  The Company has authorized the sale and issuance
of 691,883 shares of its Common Stock pursuant to this Agreement (the "Shares").

          1.2  SALE OF COMMON.  Subject to the terms and conditions of this
Agreement, the Company agrees to issue and sell to Purchaser and Purchaser
agrees to purchase from the Company 691,883 shares for $12.00 per share (the
"Purchase Price").


                                Section 2

                         CLOSING DATE; DELIVERY

          2.1  CLOSING DATE.  The closing of the purchase and sale of the Shares
hereunder (the "Closing") shall be held at the offices of Brobeck, Phleger &
Harrison LLP, 550 West "C" Street, Suite 1200, San Diego, California 92101 at
4:30 p.m. on or before April 7, 1998, or at such other time and place upon which
the Company and the Purchaser shall agree.  The date of the Closing is
hereinafter referred to as the "Closing Date."

          2.2  DELIVERY.  At the Closing, the Company will deliver to Purchaser
a certificate, registered in the Purchaser's name, representing the number of
Shares to be purchased by the Purchaser.  Such delivery shall be against payment
of the purchase price therefor by check or wire transfer to the Company in the
amount of the Purchase Price.

                                      

<PAGE>


                                Section 3

              REPRESENTATIONS AND WARRANTIES OF THE COMPANY

          The Company represents and warrants to Purchaser as of the Closing
Date as follows:

          3.1  ORGANIZATION AND STANDING.  The Company is a corporation duly
organized and validly existing under, and by virtue of, the laws of the State of
Delaware and is in good standing as a domestic corporation under the laws of
said state.

          3.2  CORPORATE POWER; AUTHORIZATION.  The Company has all requisite
legal and corporate power and has taken all requisite corporate action to
execute and deliver this Agreement, to sell and issue the Shares and to carry
out and perform all of its obligations under this Agreement.  This Agreement
constitutes the legal, valid and binding obligation of the Company, enforceable
in accordance with its terms, except (i) as limited by applicable bankruptcy,
insolvency, reorganization or similar laws relating to or affecting the
enforcement of creditors' rights generally and (ii) as limited by equitable
principles generally.  The execution and delivery of this Agreement does not,
and the performance of this Agreement and the compliance with the provisions
hereof and the issuance, sale and delivery of the Shares by the Company will
not, materially conflict with, or result in a material breach or violation of
the terms, conditions or provisions of, or constitute a material default under,
or result in the creation or imposition of any material lien pursuant to the
terms of, the Certificate of Incorporation or Bylaws of the Company or any
statute, law, rule or regulation or any state or federal order, judgment or
decree or any indenture, mortgage, lease or other material agreement or
instrument to which the Company or any of its properties is subject.

          3.3  ISSUANCE AND DELIVERY OF THE SHARES.  The Shares, when issued in
compliance with the provisions of this Agreement, will be validly issued, fully
paid and nonassessable.  The issuance and delivery of the Shares is not subject
to preemptive or any other similar rights of the stockholders of the Company or
any liens or encumbrances.

          3.4  GOVERNMENTAL CONSENTS.  No consent, approval, order or
authorization of, or registration, qualification, designation, declaration or
filing with, any federal, state, or local governmental authority on the part of
the Company is required in connection with the consummation of the transactions
contemplated by this Agreement except for (a) such filings as have been made
prior to the Closing, except that any notices of sale required to be filed with
the SEC under Regulation D of the Securities Act, or such post-closing filings
as may be required under applicable state securities laws, which will be timely
filed within the applicable periods therefor and (b) the filing of the Listing
Application with the New York Stock Exchange.

          3.5  SEC DOCUMENTS; FINANCIAL STATEMENTS.  As of their respective
filing dates, all documents (the "SEC Documents") filed by the Company with the
Securities and Exchange Commission (the "SEC") complied in all material respects
with the requirements of the Securities Exchange Act of 1934, as amended (the
"Exchange Act") or the Securities Act of 1933, as amended (the "Securities
Act"), as applicable.  None of the SEC Documents as of their respective dates


                                      2.


<PAGE>


contained any untrue statement of material fact or omitted to state a material
fact required to be stated therein or necessary to make the statements made
therein, in light of the circumstances under which they were made, not
misleading.

          3.6  NO MATERIAL ADVERSE CHANGE.  Except as otherwise disclosed
herein, since September 30, 1997, there have not been any changes in the assets,
liabilities, financial condition, business prospects or operations of the
Company from that reflected in the Financial Statements except changes in the
ordinary course of business which have not been, either individually or in the
aggregate, materially adverse.


                                Section 4

          REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PURCHASER

          Purchaser hereby represents and warrants to the Company as of the
Closing Date as follows:

          4.1  AUTHORIZATION.  Purchaser represents and warrants to the Company
that:  (i) Purchaser has all requisite legal and corporate or other power and
capacity and has taken all requisite corporate or other action to execute and
deliver this Agreement, to purchase the Shares and to carry out and perform all
of its obligations under this Agreement; and (ii) this Agreement constitutes the
legal, valid and binding obligation of the Purchaser, enforceable in accordance
with its terms, except (a) as limited by applicable bankruptcy, insolvency,
reorganization, or similar laws relating to or affecting the enforcement of
creditors' rights generally and (b) as limited by equitable principles
generally.

          4.2  INVESTMENT EXPERIENCE.  Purchaser is an "accredited investor" as
defined in Rule 501(a) under the Securities Act.  Purchaser is aware of the
Company's business affairs and financial condition and has had access to and has
acquired sufficient information about the Company to reach an informed and
knowledgeable decision to acquire the Shares.  Purchaser has such business and
financial experience as is required to give it the capacity to protect its own
interests in connection with the purchase of the Shares.

          4.3  INVESTMENT INTENT.  Purchaser is purchasing the Shares for its
own account as principal, for investment purposes only, and not with a present
view to, or for, resale, distribution or fractionalization thereof, in whole or
in part, within the meaning of the Securities Act.  Purchaser understands that
its acquisition of the Shares has not been registered under the Securities Act
or registered or qualified under any state securities law in reliance on
specific exemptions therefrom, which exemptions may depend upon, among other
things, the bona fide nature of Purchaser's investment intent as expressed
herein.  Purchaser has completed or caused to be completed the Purchaser
Questionnaire attached hereto as EXHIBIT B, and the responses provided therein
shall be true and correct as of the Closing Date.  Purchaser has, in connection
with its decision to purchase the Shares relied solely upon the SEC Documents
and the representations and warranties of the 


                                      3.


<PAGE>

Company contained herein. Purchaser will not, directly or indirectly, offer, 
sell, pledge, transfer or otherwise dispose of (or solicit any offers to buy, 
purchase or otherwise acquire or take a pledge of) any of the Shares except 
in compliance with the Securities Act, and the rules and regulations 
promulgated thereunder.

          4.4  REGISTRATION OR EXEMPTION REQUIREMENTS.  Purchaser further
acknowledges and understands that the Shares may not be resold or otherwise
transferred except in a transaction registered under the Securities Act or
unless an exemption from such registration is available.  

          4.5  RESTRICTION ON SHORT SALES.  Purchaser represents and warrants to
and covenants with the Company that Purchaser has not engaged and will not
engage in any short sales of the Company's Common Stock prior to the
effectiveness of a registration statement registering the resale of the Shares,
except to the extent that any such short sale is fully covered by shares of
Common Stock of the Company other than the Shares.

          4.6  NO LEGAL, TAX OR INVESTMENT ADVICE.  Purchaser understands that
nothing in this Agreement or any other materials presented to Purchaser in
connection with the purchase and sale of the Shares constitutes legal, tax or
investment advice.  Purchaser has consulted such legal, tax and investment
advisors as it, in its sole discretion, has deemed necessary or appropriate in
connection with its purchase of the Shares.

          4.7  LEGENDS.  To the extent applicable, each certificate or other
document evidencing any of the Shares shall be endorsed with the legends set
forth below, and the Purchaser covenants that, except to the extent such
restrictions are waived by the Company, the Purchaser shall not transfer the
shares represented by any such certificate without complying with the
restrictions on transfer described in the legends endorsed on such certificate:

               (a)  "THE SHARES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD,
TRANSFERRED, ASSIGNED, PLEDGED, OR HYPOTHECATED ABSENT AN EFFECTIVE REGISTRATION
THEREOF UNDER SUCH ACT OR COMPLIANCE WITH RULE 144 PROMULGATED UNDER SUCH ACT,
OR UNLESS THE COMPANY HAS RECEIVED AN OPINION OF COUNSEL, SATISFACTORY TO THE
COMPANY AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED."

               (b)  "THE SHARES REPRESENTED HEREBY ARE SUBJECT TO THE
RESTRICTIONS ON TRANSFER CONTAINED IN A CERTAIN COMMON STOCK PURCHASE AGREEMENT,
AS AMENDED FROM TIME TO TIME.  THE COMPANY WILL UPON WRITTEN REQUEST FURNISH A
COPY OF SUCH AGREEMENT TO THE HOLDER HEREOF WITHOUT CHARGE."

               (c)  Any other legend required by law.


                                      4.


<PAGE>

                                Section 5

                   CONDITIONS TO CLOSING OF PURCHASER

          Purchaser's obligation to purchase the Shares at the Closing is, at
the option of Purchaser, subject to the fulfillment or waiver as of the Closing
Date of the following conditions:

          5.1  REPRESENTATIONS AND WARRANTIES.  The representations and
warranties of the Company contained in Section 3 shall be true on and as of the
Closing with the same effect as though such representations and warranties had
been made on and as of the date of such Closing.

          5.2  PERFORMANCE.  The Company shall have performed and complied with
all agreements, obligations and conditions contained in this Agreement that are
required to be performed or complied with by it on or before the Closing.

          5.3  QUALIFICATIONS.  All authorizations, approvals, or permits, if
any, of any governmental authority or regulatory body of the United States or of
any state that are required as of the Closing in connection with the lawful
issuance and sale of the Shares pursuant to this Agreement shall have been duly
obtained and shall be effective as of the Closing.

          5.4  COMPLIANCE CERTIFICATE.  An officer of the Company shall have
delivered to Purchaser a certificate certifying that the conditions specified in
Sections 5.1 and 5.2 have been fulfilled.


                                Section 6

                    CONDITIONS TO CLOSING OF COMPANY

          The Company's obligation to sell and issue the Shares at the Closing
is, at the option of the Company, subject to the fulfillment or waiver of the
following conditions:

          6.1  REPRESENTATIONS AND WARRANTIES.  The representations and
warranties of the Purchaser contained in Section 4 shall be true on and as of
the Closing with the same effect as though such representations and warranties
had been made on and as of the date of such Closing.

          6.2  COVENANTS.  The Purchaser shall have performed and complied with
all agreements, obligations and conditions contained in this Agreement that are
required to be performed or complied with by the Purchaser on or before the
Closing.

          6.3  QUALIFICATIONS.  All authorizations, approvals, or permits, if
any, of any governmental authority or regulatory body of the United States or of
any state that are required as of the Closing in connection with the lawful
issuance and sale of the Shares pursuant to this Agreement shall have been duly
obtained and shall be effective as of the Closing.

                                      5.



<PAGE>


          6.4  COMPLIANCE CERTIFICATE.  An officer of Purchaser shall have
delivered to the Company a certificate certifying that the conditions specified
in Sections 6.1 and 6.2 have been fulfilled.


                              Section 7

                        ADDITIONAL COVENANTS

          7.1  STANDSTILL PROVISIONS.  Commencing as of the Closing and through
the fifth anniversary of the Effective Date, Purchaser (including all affiliates
(as defined in Rule 144) of the Purchaser ("Affiliate")) shall not acquire
beneficial ownership of any shares of Common Stock of the Company, any
securities convertible into or exchangeable for Common Stock, or any other right
to acquire Common Stock, except by way of stock dividends or other distributions
or offerings made available to holders of Common Stock generally (collectively,
"Company Stock"), from the Company or any other person or entity without the
prior written consent of the Company, which consent may be withheld in its sole
discretion; PROVIDED, HOWEVER, that in no event shall (i) the original purchase
of Shares pursuant to this Agreement or (ii) the acquisition by Purchaser (or an
Affiliate) of another Company that at the time of the acquisition owns
securities of the Company constitute a violation of this Section 7.1.

          7.2  MARKET STAND-OFF.  The Purchaser hereby agrees that during the
period of duration not to exceed 120 days specified by the Company and an
underwriter of capital stock of the Company, following the effective date of a
registration statement pursuant to which the Company is offering securities
under the Securities Act, it shall not, to the extent requested by the Company
and such underwriter (and provided the same restriction is agreed to by the
officers and directors of the Company), directly or indirectly sell, offer to
sell, contract to sell (including, without limitation, any short sale), grant
any option to purchase or otherwise transfer or dispose of (other than to donees
who agree to be similarly bound) any securities of the Company held by it at any
time during such period except Common Stock included in such registration.  In
order to enforce the foregoing covenant, the Company may impose stop-transfer
instructions with respect to the Shares until the end of such period.


                              Section 8

             RESTRICTIONS ON TRANSFERABILITY OF SHARES:
                   COMPLIANCE WITH SECURITIES ACT

          8.1  RESTRICTIONS ON TRANSFERABILITY.  The Shares shall not be
transferable in the absence of a registration under the Securities Act or an
exemption therefrom or in the absence of compliance with any term of this
Agreement.  The Company shall be entitled to give stop transfer instructions to
its transfer agent with respect to the Shares in order to enforce the foregoing
restrictions.


                                      6.

<PAGE>


          8.2  TRANSFER OF SHARES AFTER REGISTRATION.  Purchaser hereby
covenants with the Company not to make any sale of the Shares except in
accordance with Section 7.2 AND either (i) in accordance with a registration
statement, in which case Purchaser covenants to comply with the requirement of
delivering a current prospectus, or (ii) in accordance with Rule 144, in which
case Purchaser covenants to comply with Rule 144.  Purchaser further
acknowledges and agrees that such Shares are not transferable on the books of
the Company unless the certificate submitted to the Company's transfer agent
evidencing such Shares is accompanied by a separate certificate executed by an
officer of, or other person duly authorized by, the Purchaser in the form
attached hereto as EXHIBIT C.


                              Section 9

                            MISCELLANEOUS

          9.1  AMENDMENTS AND WAIVERS.  Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or prospectively
but only if so expressly stated), only with the written consent of the Company
and Purchaser.  Any amendment or waiver effected in accordance with this Section
shall be binding upon each holder of any securities purchased under this
Agreement at the time outstanding, each future holder of all such securities,
and the Company.

          9.2  GOVERNING LAW.  This Agreement shall be governed in all respects
by and construed in accordance with the laws of the State of California without
any regard to conflicts of laws principles.

          9.3  SURVIVAL.  The representations, warranties, covenants and
agreements made in this Agreement shall survive any investigation made by the
Company or the Purchaser and the Closing.

          9.4  SUCCESSORS AND ASSIGNS.  The provisions hereof shall inure to the
benefit of, and be binding upon, the successors, assigns, heirs, executors and
administrators of the parties to this Agreement.  Notwithstanding the foregoing,
Purchaser shall not assign this Agreement without the prior written consent of
the Company.

          9.5  ENTIRE AGREEMENT.  This Agreement constitutes the full and entire
understanding and agreement between the parties with regard to the subjects
hereof.

          9.6  NOTICES, ETC.  All notices and other communications required or
permitted under this Agreement shall be in writing and may be delivered in
person, by facsimile, overnight delivery service or registered or certified
mail, addressed to the Company or the Purchaser, as the case may be, at their
respective addresses set forth at the beginning of this Agreement, or at such
other address as the Company or the Purchaser shall have furnished to the other
party in writing.  All notices and other communications shall be effective upon
the earlier of actual receipt thereof by


                                      7.

<PAGE>


the person to whom notice is directed or (i) in the case of notices and 
communications sent by personal delivery or facsimile, one business day after 
such notice or communication arrives at the applicable address or was 
successfully sent to the applicable facsimile number, (ii) in the case of 
notices and communications sent by overnight delivery service, at noon (local 
time) on the second business day following the day such notice or 
communication was sent, and (iii) in the case of notices and communications 
sent by United States mail, seven days after such notice or communication 
shall have been deposited in the United States mail.

          9.7  SEVERABILITY OF THIS AGREEMENT.  If any provision of this
Agreement shall be judicially determined to be invalid, illegal or
unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

          9.8  COUNTERPARTS.  This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

          9.9  FURTHER ASSURANCES.  Each party to this Agreement shall do and
perform or cause to be done and performed all such further acts and things and
shall execute and deliver all such other agreements, certificates, instruments
and documents as the other party hereto may reasonably request in order to carry
out the intent and accomplish the purposes of this Agreement and the
consummation of the transactions contemplated hereby.

          9.10 TERMINATION.  In the event that the Closing shall not have
occurred on or before ninety (90) days from the date hereof, this Agreement
shall terminate at the close of business on such date.

          9.11 EXPENSES.  The Company and Purchaser shall bear its own expenses
incurred on its behalf with respect to this Agreement and the transactions
contemplated hereby, including fees of legal counsel.


                                      8.


<PAGE>


          9.12 CURRENCY.  All references to "dollars" or "$" in this Agreement
shall be deemed to refer to United States dollars.

          The foregoing agreement is hereby executed as of the date first above
written.


                                   "COMPANY"

                                   MOLECULAR BIOSYSTEMS, INC.,
                                   a Delaware corporation


                                   By:    /s/ B. Venkatadri         
                                          ------------------------------------

                                   Title: President and CEO    
                                          ------------------------------------


                                   "PURCHASER"


                                   CHUGAI PHARMACEUTICAL CO., LTD.


                                   By:    /s/ ILLEGIBLE             
                                          ------------------------------------

                                   Title: President            
                                          ------------------------------------


                                      9.


<PAGE>


                                                                  Exhibit A


                   INSTRUCTION SHEET FOR PURCHASER

             (to be read in conjunction with the entire
                  Common Stock Purchase Agreement)



A.   Complete the following items in the Common Stock Purchase Agreement:

     1.   Provide the information regarding the Purchaser requested on the
          signature page.  The Agreement must be executed by an individual
          authorized to bind the Purchaser.

     2.   Exhibit B-1 - Stock Certificate Questionnaire:

          Provide the information requested by the Stock Certificate
          Questionnaire;

     3.   Exhibit B-2 - Purchaser Certificate:

          Provide the information requested by the Certificate for Corporate,
          Partnership, Trust, Foundation and Joint Purchasers, as applicable.

     4.   Return the signed Purchase Agreement including the properly completed
          Exhibits B-1 and B-2 to:

               Molecular Biosystems, Inc.
               10030 Barnes Canyon Road
               San Diego, CA USA 92121-2789

B.   Instructions regarding the transfer of funds for the purchase of Shares
     will be sent by facsimile to the Purchaser by the Company at a later date.

C.   In the event the Purchaser elects to resell the Shares pursuant to Rule 144
     of the Securities Act of 1933, as amended ("Rule 144"), the Purchaser, 

          (i)  must comply with all of the requirements of Rule 144 for resale
               of securities; and

          (ii) must send a letter in the form of Exhibit C to the Company so
               that the Shares may be properly transferred.

D.   In the event the Purchaser elects to resell the Shares pursuant to the
     Registration Statement after the Registration Statement covering the Shares
     is effective, as described in the Purchase Agreement, the Purchaser:

     (i)  must deliver a current prospectus, and annual and quarterly
          reports of the Company to the buyer (prospectuses, and annual and
          quarterly reports may be obtained from the Company at the
          Purchaser's request); and
                                                                  
     (ii) must send a letter in the form of Exhibit C to the Company so
          that the Shares may be properly transferred.


<PAGE>
                                                                   
                                                                  Exhibit B-1



                     MOLECULAR BIOSYSTEMS, INC.

                   STOCK CERTIFICATE QUESTIONNAIRE

     Pursuant to Section 4.3 of the Agreement, please provide us with the
     following information:

1.   The exact name that the Shares are to be
     registered in (this is the name that will
     appear on the stock certificate(s)).  You 
     may use a nominee name if appropriate:

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

2.   The relationship between the Purchaser of
     the Shares and the Registered Holder
     listed in response to item 1 above:

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

                                                                    
3.   The mailing address of the Registered 
     Holder listed in response to item 1 above:

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

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

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

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

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

4.   The Tax Identification Number of the 
     Registered Holder listed in response to
     item 1 above:

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


<PAGE>


                                                                  Exhibit B-2

                     MOLECULAR BIOSYSTEMS, INC.

               CERTIFICATE FOR CORPORATE, PARTNERSHIP,
               TRUST, FOUNDATION AND JOINT PURCHASERS

          If the investor is a corporation, partnership, trust, pension plan,
foundation, joint purchaser (other than a married couple) or other entity, an
authorized officer, partner, or trustee must complete, date and sign this
Certificate.

                             CERTIFICATE

          The undersigned certifies that the representations and responses below
are true and accurate:

          (a)  The investor has been duly formed and is validly existing and has
full power and authority to invest in the Company.  The person signing on behalf
of the undersigned has the authority to execute and deliver the Common Stock
Purchase Agreement on behalf of the Purchaser and to take other actions with
respect thereto.

          (b)  Indicate the form of entity of the undersigned:

               ___  Limited Partnership

               ___  General Partnership

               ___  Corporation

               ___  Revocable Trust (identify each grantor and indicate under
                    what circumstances the trust is revocable by the grantor: 

                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ------------------.  (Continue on a separate piece of 
                    paper, if necessary.)

               ___  OTHER TYPE OF TRUST (INDICATE TYPE OF TRUST AND, FOR TRUSTS
                    OTHER THAN PENSION TRUSTS, NAME THE GRANTORS AND
                    BENEFICIARIES:                                  
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    ----------------------------------------------------------
                    -----------------.  (Continue on a separate piece of 
                    paper, if necessary.)

               ___  Other form of organization (indicate form of organization
                     (--------------------).
                      
          (c)  Indicate the approximate date the undersigned entity was formed:
               --------------------------.

          (d)  In order for the Company to offer and sell the Shares in
conformance with state and federal securities laws, the following information
must be obtained regarding your investor status.  Please INITIAL EACH CATEGORY
applicable to you as an investor in the Company.

          ___  1.   A bank as defined in Section 3(a)(2) of the Securities Act,
          or any savings and loan association or other institution as defined in
          Section 3(a)(5)(A) of the Securities Act whether acting in its
          individual or fiduciary capacity;


<PAGE>


          ___  2.   A broker or dealer registered pursuant to Section 15 of the
          Securities Exchange Act of 1934;

          ___  3.   An insurance company as defined in Section 2(13) of the
          securities Act;

          ___  4.   An investment company registered under the Investment
          Company Act of 1940 or a business development company as defined in
          Section 2(a)(48) of that Act;

          ___  5.   A Small Business Investment Company licensed by the U.S.
          Small Business Administration under Section 301(c) or (d) of the Small
          Business Investment Act of 1958;

          ___  6.   A plan established and maintained by a state, its political
          subdivisions, or any agency or instrumentality of a state or its
          political subdivisions, for the benefit of its employees, if such plan
          has total assets in excess of $5,000,000;

          ___  7.   An employee benefit plan within the meaning of the Employee
          Retirement Income Security Act of 1974, if the investment decision is
          made by a plan fiduciary, as defined in Section 3(21) of such act,
          which is either a bank, savings and loan association, insurance
          company, or registered investment adviser, or if the employee benefit
          plan has total assets in excess of $5,000,000 or, if a self-directed
          plan, with investment decisions made solely by persons that are
          accredited investors;

           ___ 8.   A private business development company as defined in
          Section 202(a)(22) of the Investment Advisers Act of 1940;

          ___  9.   An organization described in Section 501(c)(3) of the
          Internal Revenue Code, a corporation, Massachusetts or similar
          business trust, or partnership, not formed for the specific purpose of
          acquiring the Shares, with total assets in excess of $5,000,000;

          ___  10.  A trust, with total assets in excess of $5,000,000, not
          formed for the specific purpose of acquiring the Shares, whose
          purchase is directed by a sophisticated person who has such knowledge
          and experience in financial and business matters that such person is
          capable of evaluating the merits and risks of investing in the
          Company;

          ___  11.  An entity in which ALL of the equity owners qualify under
          any of the above subparagraphs.  If the undersigned belongs to this
          investor category only, list the equity owners of the undersigned, and
          the investor category which each such equity owner satisfies:
          --------------------------------------------------------------------
          --------------------------------------------------------------------
          --------------------------------------------------------------------
          --------------------------------------------------------------------.
          (Continue on a separate piece of paper, if necessary.)


Dated:                        , 19
          --------------------    ---

                              ------------------------------------------------
                              Name of investor



                              ------------------------------------------------
                              Signature and title of authorized
                              officer, partner or trustee


<PAGE>


                                                                  Exhibit C


             PURCHASER'S CERTIFICATE OF SUBSEQUENT SALE


To:  Molecular Biosystems, Inc.
     10030 Barnes Canyon Road
     San Diego, CA USA 92121-2789  

     Attention:  General Counsel

          The undersigned, the Purchaser or an officer of, or other person duly

authorized by, the Purchaser, hereby certifies that 
                                                   ---------------------------
- -------------------------------------                       (fill in name 
         of Purchaser)               institution was the

Purchaser of the shares evidenced by the attached certificate, and as such,

proposes to transfer such shares on or about                   either (i) in
                                            -------------------
                                                   (date)
accordance with the registration statement, file number [__________] in which

case the Purchaser certifies that the requirement of delivering a current 

prospectus has been complied with or will be complied with in connection with 

such sale, or (ii) in accordance with Rule 144 under the Securities Act of 1933,

as amended ("Rule 144"), in which case the Purchaser certifies that it has

complied with or will comply with the requirements of Rule 144.

Print or type:
               
                     Name of Purchaser:                               
                                          ------------------------------------

                     Name of Individual 
                     representing
                     Purchaser (if an 
                     Institution):                                       
                                          ------------------------------------

                     Title of Individual
                     representing
                     Purchaser (if an
                     Institution):                                       
                                          ------------------------------------

                     Signature by:

                     Purchaser or
                     Individual repre-
                     senting Purchaser:                                  
                                          ------------------------------------



<PAGE>
                                                                  Exhibit 99.1

                                                                  NEWS RELEASE

MOLECULAR BIOSYSTEMS, INC.
     ROBERT P. GIARGIARI, INVESTOR RELATIONS (619) 812-7179
     PATRICIA SULLIVAN, CORPORATE COMMUNICATIONS (619) 812-7146
     E-MAIL:  [email protected]



           MOLECULAR BIOSYSTEMS AND CHUGAI PHARMACEUTICALS ESTABLISH
           A MULTIPLE PRODUCT ALLIANCE FOR ULTRASOUND IMAGING AGENTS


     SAN DIEGO, CALIF. and Tokyo, Japan, April 8, 1998 -- Molecular 
Biosystems, Inc. (NYSE:MB) ("MBI") and Chugai Pharmaceuticals Wednesday 
announced that they have entered into an exclusive license agreement for the 
development and sale of two products, FS069 and ORALEX-Registration Mark- in 
Japan, Taiwan and South Korea.  This alliance reflects each company's 
commitment to be a world leader in the development and commercialization of 
contrast agents for the rapidly growing ultrasound field.

     In exchange for granting to Chugai a royalty-based license to market 
these products in the named countries, MBI will receive an upfront license 
fee from Chugai of $14 million.  In addition, Chugai will make an equity 
investment in MBI common stock. MBI will also receive milestone payments of 
up to $20 million based on the achievement of certain product development 
goals and will receive royalties from Chugai from the sale of commercialized 
products in the territory.

     FS069, the first and only commercially available perfluorocarbon based 
cardiac ultrasound contrast imaging agent, is now licensed for sale in every 
territory around the world.  To date, FS069 is the first and only 
perfluorocarbon based agent to have been approved for sale in the United 
States by the U.S. Food and Drug Administration and additionally is the first 
to have been recommended for approval in Europe by the Committee for 
Proprietary Medicinal Products.  Marketing authorization in Japan would give 
Chugai and MBI access to the world's second largest market for ultrasound 
imaging.

     ORALEX, which recently completed Phase 2 clinical trials in the U.S., is 
a proprietary oral ultrasound agent designed to distend the stomach and to 
displace gases in order to provide physicians with a better view into the 
upper gastrointestinal (GI) anatomy, including the stomach wall and pancreas.


<PAGE>

     Bobba Venkatadri, president and CEO of MBI, commented on the 
significance of this new strategic alliance:  "In extending our leadership 
position in the ultrasound arena, MBI is committed to the global development 
and commercialization of multiple products along multiple technology 
platforms. The inclusion of both FS069 and ORALEX in this partnership 
validates the world-class scientific efforts underway at MBI and gives us the 
opportunity to build a successful product franchise in the Far East."

     "Chugai, as one of the largest pharmaceutical companies in Japan, is an 
ideal partner given its extensive skills and experience in product 
development and marketing.  We are confident in their ability to move 
aggressively toward bringing MBI's exciting products to market," added 
Venkatadri.

      "We view this partnership as an excellent match, given each company's 
common goal to define the standards in ultrasound contrast imaging," Osamu 
Nagayama, president of Chugai.  "After examining carefully several products 
under development in this field and the growth potential for ultrasound 
contrast, we concluded that MBI's combination of products would give us a 
distinct competitive edge in terms of efficacy, safety, and marketability.  
We look forward to continuing Chugai's legacy of achievements by making FS069 
and ORALEX major successes in Japan, Taiwan and South Korea."

     Molecular Biosystems (NYSE: MB), based in San Diego, California, is a 
world leader in the development and commercialization of ultrasound contrast 
agents for diagnostic imaging.  The company's breakthrough products, 
including FS069 and ORALEX, enables improved diagnoses of disease through 
clearer ultrasound images.  Information about MBI may be obtained via fax by 
calling 888/329-4007 (toll-free) or via the internet by pointing your browser 
to (http://www.mobi.com).

     Chugai Pharmaceuticals, Ltd., based in Tokyo, is a major research-based, 
fully-integrated Japanese pharmaceutical company, known for its innovative 
products.

     This news release contains forward-looking statements that involve risk 
and uncertainties. The commercialization of FS069 and ORALEX in Japan, Taiwan 
or South Korea may differ from the companies' expectation. Among the factors 
that could result in a materially different outcome are: the failure of FS069 
or ORALEX to gain marketing authorization or market acceptance in the 
territories; and other risk factors reported from time to time in MBI's 
filings with the Securities Exchange Commission.





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