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                                                                  EXHIBIT 10.34


                               FIRST AMENDMENT TO
                         INTERNATIONAL LICENSE AGREEMENT
                                     BETWEEN
           ABBOTT INTERNATIONAL, LTD. AND SONUS PHARMACEUTICALS, INC.

        THIS FIRST AMENDMENT ("Amendment") dated January 31, 1999 ("Amendment
Effective Date"), by and between Abbott International, Ltd., a Delaware
corporation with principal offices at 100 Abbott Park Road, Abbott Park,
Illinois 60064-3500 ( "ABBOTT") and SONUS Pharmaceuticals, Inc., a Delaware
corporation with principal offices at 22026 20th Avenue, S.E., Suite 102,
Bothell, Washington 98021 ("SONUS").

                                    RECITALS

        WHEREAS, ABBOTT and SONUS have previously entered into an International
License Agreement dated October 1, 1996 ("International Agreement"), whereby
ABBOTT obtained certain exclusive marketing rights for certain territories
outside of the United States, subject to limited SONUS co-promotion rights, to
certain ultrasound contrast agents;

        WHEREAS, ABBOTT and SONUS desire to amend the International Agreement as
set forth in this Amendment;

        NOW, THEREFORE, in consideration of the premises and the mutual promises
and covenants set forth below, ABBOTT and SONUS mutually agree as follows:

1.      Capitalized terms used in this Amendment and not otherwise defined in
        this Amendment shall have the meanings set forth in the International
        Agreement. Article 1 of the International Agreement is amended as
        follows: (a) Article 1.10 is amended as follows:

                "First Sale Date" means the earlier of: (i) the date of the
first sale of the Product in a given Major Country following the Approval
Date(as defined


                      [*] CONFIDENTIAL PORTIONS OMITTED AND
                      FILED SEPARATELY WITH COMMISSION



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               below) in such Major Country by ABBOTT or an ABBOTT Affiliate or
               sublicensee to a Third Party; or (ii) the date ninety (90) days
               after the Approval Date in such Major Country."

        (b) The following new definitions are added to Article 1:

               "1.24" 'Approval Date' means the later to occur of the date of
               Regulatory Approval by the European Medicines Evaluation Agency
               ("EMEA") of the Product for (i) the Cardiology Indication and
               (ii) the Radiology Indication. 

               "1.25" 'Cardiology Indication' means the indication for the
               Product [*] 

               "1.26" 'Radiology Indication' means the indication for the
               Product [*]

2.      The introduction of Article 2.1(A) of the International Agreement is
        amended as follows:

               "(A) SONUS shall be responsible for all activities required to
               obtain Regulatory Approval, exclusive of price approval and
               reimbursement approval, in Countries which as of the Effective
               Date, are members of the European Community ('EC Countries).
               These activities will include, but not be limited to, clinical
               trials and the filing of an application for marketing approval
               with the EMEA. SONUS will pursue these activities diligently and
               will use its reasonable best efforts to obtain such Regulatory
               Approval, exclusive of price approval and reimbursement approval,
               as quickly as is feasible. ABBOTT shall be responsible for all
               activities required to obtain price approval and reimbursement
               approval in such EC Countries. ABBOTT will pursue such activities
               diligently and will use its reasonable best efforts to obtain
               such price approvals and reimbursement approvals as quickly as is
               feasible."

3.      Article 2.2(A) of the International Agreement is amended as follows:

               "(A) If ABBOTT desires to participate financially in such
               additional clinical research, and communicates its decision to
               participate in accordance with Article 2.4 of the United States
               Agreement, as amended, SONUS shall reimburse ABBOTT fifty percent
               (50%) of such costs and expenses funded by ABBOTT ('Reimbursement
               Amount') by either, at the option of SONUS:

                      (i) reimbursing ABBOTT in cash such Reimbursement Amount
                      with interest at the United States prime rate of interest
                      (as published in the Wall Street 



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                      Journal Midwest Edition on the date on which ABBOTT funds
                      such reimbursement) within five (5) years of the date such
                      Reimbursement Amount is fully paid by ABBOTT; or

                      (ii) reducing the royalty rates payable by ABBOTT to SONUS
                      as provided in Article 6.1 at such dates and in such
                      amounts as is mutually agreed by the parties; or

                      (iii) in the event that the net tangible assets of SONUS
                      shall, at any time within five (5) years of the date such
                      Reimbursement Amount is fully paid by ABBOTT, fall below
                      an amount equal to the then current Nasdaq National Market
                      listing requirements for net tangible assets contained in
                      paragraph 4450(a)(3) of the NASD Manual, as such paragraph
                      may be amended from time to time, plus One Million Dollars
                      ($1,000,000) reimbursing ABBOTT such Reimbursement Amount
                      with interest at the United States prime rate of interest
                      (as published in the Wall Street Journal Midwest Edition
                      on the date on which ABBOTT funds such reimbursement), by
                      issuing and delivering to ABBOTT within such five (5) year
                      period shares of Common Stock of SONUS having a fair
                      market value equal to such Reimbursement Amount plus such
                      interest pursuant to the terms and conditions of a
                      Securities Purchase Agreement substantially in the form
                      attached hereto as Exhibit 2.2(A), and which is
                      incorporated herein by reference; or

                      (iv) reimbursing ABBOTT partially in cash pursuant to
                      Article 2.2(A)(i) and the remainder in SONUS Common Stock
                      pursuant to Article 2.2(A)(iii). If the parties are unable
                      to agree on a reduction of the royalty rates pursuant to
                      Article 2.2(A)(ii) within thirty (30) days of the date on
                      which they began discussing such reduction, then the
                      parties shall utilize the ADR procedure pursuant to
                      Article 20 to determine the royalty rate reduction. Once
                      the ADR procedure has been initiated, and through the date
                      of the final ADR decision, ABBOTT may deduct 10% from its
                      royalty payments to SONUS. Promptly after the ADR
                      decision, ABBOTT shall pay SONUS the balance of royalty
                      payments due under the reduced royalty rate (if any), or
                      SONUS shall repay to ABBOTT the overpayment by ABBOTT (if
                      any). Any such amount due



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                      from one party to the other shall be due and payable (with
                      interest at the prime rate of interest as published in the
                      Wall Street Journal Midwest Edition on the date of the ADR
                      decision) within thirty (30) days of the owing party's
                      receipt of the ADR decision."

4.      The second sentence of Article 3.2(A) of the International Agreement is
        amended as follows:

                      "ABBOTT shall use its reasonable best efforts to optimize
                      sales, profitability, and market share of the Product in
                      the Territory in a manner consistent with the efforts
                      which it exerts to optimize sales, profitability, and
                      market share of its other products in the Territory."

5.      Article 3.2(B)(i)(c)(1) of the International Agreement is amended as
        follows:

                      "(1) ABBOTT's failure to make the minimum royalty payment
                      in a Major Country in the Territory was due to the fact
                      that the Approval Date did not occur within the time frame
                      contemplated by the parties as set forth in the Plan for
                      that Major Country. The Net Sales forecast shall be
                      adjusted as mutually agreed by the parties to reflect the
                      actual Approval Date and the actual indications approved,
                      and any material changes to the assumptions for the Net
                      Sales forecast, including without limitation any
                      additional indications which may be approved as
                      contemplated in Section 2.2. If the parties are unable to
                      agree on such adjustment within thirty (30) days of the
                      date on which they began discussing such adjustment, then
                      the parties will utilize the Dispute Resolution Procedure
                      under Article 20 to determine such adjustment."

6.      Article 3.4(A) of the International Agreement is deleted and replaced
        with the following:

               (A) ABBOTT and SONUS have previously entered into a Development
               and Supply Agreement dated May 6, 1993, as amended ("the Supply
               Agreement") under which ABBOTT has agreed to manufacture the
               Product for SONUS. SONUS may purchase Product under the Supply
               Agreement to fulfill ABBOTT's purchase orders under Article 3.5.
               All manufacturing of the Product by ABBOTT for sale in the



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               Territory by ABBOTT shall be in accordance with the terms of the
               Supply Agreement, as amended from tie to time, and the
               specifications for the Product under the Supply Agreement."

7.      Article 3.4 of the International Agreement is amended by adding the
        following:

               "(E) ABBOTT and SONUS agree that during the term of this
               Agreement a certain portion of the Product will be packaged [*].
               In the early years following the First Sale Date of the Product
               packaged [*] in the E.U., a larger percentage of total Unit Sales
               shall consist of [*], whereas in later years, ABBOTT shall move
               toward selling a larger percentage of the total Unit Sales of
               [*], in accordance with the following guidelines:

                                       [*]

        In the event that actual Unit Sales of [*] as a percentage of total Unit
        Sales exceed the percentage thresholds set forth in this Subsection (E),
        ABBOTT and SONUS agree to discuss an adjustment of the percentages or
        modifications to [*] or a modification to the royalty rates under
        Article 6, as appropriate." If the parties are unable to agree upon a
        reasonable adjustment or modification within thirty (30) days of the
        date on which they began discussing such adjustment or modifications,
        then the parties shall use the ADR procedure pursuant to Article 20 to
        determine such adjustment or modifications (if any).

8.      Article 4 of the International Agreement shall be amended by adding the
        following last sentence:

                "ABBOTT agrees that, as of the Amendment Effective Date, SONUS
                has fulfilled its obligations to ABBOTT relating to the
                SONUS/Daiichi Agreement under this Article 4."

9.      SONUS acknowledges that ABBOTT has exercised the options granted under
        Article 5.1(C)(i) and Article 5.1(C)(ii), and that the licenses relating
        respectively to such options have been granted to ABBOTT and are part
        of, and subject to the terms and conditions of, the International
        Agreement as modified by this Amendment.



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10.     SONUS acknowledges that the amounts referred to in items 1,2 and 3 of
        Appendix 5.2 and in items 1,2 and 3 of Appendix 5.3 of the International
        Agreement, as modified by this Amendment, have been paid by ABBOTT to
        SONUS in full prior to the Amendment Effective Date.

11.     New Articles 5.4 and 5.5 are added to the International Agreement as
        follows:

                "5.4 Acceleration of Radiology Milestone Payments. As indicated
                in Appendices 5.2 and 5.3 of the International Agreement, as
                modified by this Amendment, certain of the milestone payments
                have been conditioned upon the achievement of specific
                milestones relating to specified indications for the Product.
                Fifty percent (50%) of each such payment is to be earned based
                on approval of the Cardiology Indication ('Cardiology Milestone
                Payment') and the remaining fifty percent (50%) is to be earned
                based on approval of the Radiology Indication or of a radiology
                indication mutually agreed by the parties in writing hereafter
                ('Radiology Milestone Payment').

                5.5 Prepayment of Radiology Milestone. Within one (1) year
                following the Radiology Prepayment Date (as such term is defined
                in Exhibit A to the Securities Purchase Agreement), SONUS shall
                have the right to request that ABBOTT prepay any or all of such
                Radiology Milestone Payments in consideration for the issuance
                by SONUS to ABBOTT of shares of SONUS Common Stock pursuant to
                and subject to the terms and conditions of the Securities
                Purchase Agreement in the form attached hereto as Exhibit
                2.2(A), the terms and conditions of which Securities Purchase
                Agreement are incorporated herein by reference. Anything herein
                or in the Securities Purchase Agreement notwithstanding, SONUS
                shall not have the right to request that ABBOTT make any
                prepayment of any Radiology Milestone Payment, (i) relating to
                the U.S. NDA approval milestone unless and until SONUS has
                received the first U.S. FDA approval of the Product in the Field
                (as defined in the United States Agreement), and (ii) relating
                to the first shipment date of Product for sale in Germany,
                France, Italy, Spain, Canada or



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                the United Kingdom milestone, unless and until the first
                shipment of Product has occurred in any such country. If SONUS
                does not request prepayment of the Radiology Milestone Payments
                within such one (1) year period as provided in the Securities
                Purchase Agreement, ABBOTT shall not be obligated to pay the
                Radiology Milestone Payments until such time as SONUS obtains
                EMEA approval of the Radiology Indication. In the event that
                ABBOTT has prepaid any or all of the Radiology Milestone
                Payments, SONUS shall repay thirty percent (30%) of the dollar
                value of such prepaid amount ("Repayment Amount") to ABBOTT if
                SONUS fails to achieve the Radiology Milestone on or before the
                date which is [*] following the Amendment Effective Date. SONUS
                shall pay to ABBOTT the Repayment Amount by either, at the
                option of SONUS: (i) repaying ABBOTT the Repayment Amount in the
                form of cash within ten (10) days following the date which is
                [*] following the Amendment Effective Date; or (ii) issuing and
                delivering to ABBOTT a number of shares of Common Stock of SONUS
                equal to the Repayment Amount pursuant to the terms and
                conditions of the Securities Purchase Agreement.

12.     Article 6.1 of the International Agreement is amended as follows:

                "Royalty Rate. The Royalty Rate applicable to calculate ABBOTT's
                Royalty payment, pursuant to Article 6.2 below, shall be based
                upon the number of approved indications for the Product in
                Germany, France, Italy, Spain and the United Kingdom, and upon
                the level of ABBOTT's aggregate annual Net Sales in the
                Territory, as set forth in Appendix 6.1 to this Amendment."

13.     As of the Amendment Effective Date, SONUS has under development an
        ultrasound diagnostic imaging product within the Field which SONUS has
        designated as [*]. SONUS and ABBOTT acknowledge and agree that: (i) [*]
        falls within the definition of "Product" (although all specific terms
        and conditions with respect to [*] shall be set forth in a separate



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        agreement between ABBOTT and SONUS), and (ii) ABBOTT has exclusive
        rights to market and sell [*]. SONUS and ABBOTT shall exert all
        reasonable efforts to negotiate in good faith, execute and deliver a
        separate agreement with respect to [*].

14.     Registration Rights. SONUS shall, prior to or on the Amendment Effective
        Date, cause to be amended the Sonus Pharmaceuticals, Inc. Third Amended
        and Restated Registration Rights Agreement dated May 15, 1996, as
        amended ("Registration Rights Agreement"), to include the shares of
        Common Stock issued by SONUS to ABBOTT and Common Stock issuable upon
        exercise of the Warrants pursuant to the United States Agreement, as
        amended, and the Securities Purchase Agreement, as "Registrable
        Securities" as the term "Registrable Securities" is defined in the
        Registration Rights Agreement.

15.     Appendices. Appendices of the International Agreement are amended as set
        forth in the corresponding Appendices attached to this Amendment.

16.     Confidentiality. In the event that this Amendment is to be filed with
        the Securities and Exchange Commission, ABBOTT and SONUS shall discuss
        any request for confidential treatment of certain financial and other
        terms of this Amendment and cooperate in the preparation and filing of
        any confidential treatment requests submitted to the Securities and
        Exchange Commission with respect to this Amendment.

17.     Counterparts. This Amendment may be executed in any number of
        counterparts, each of which shall be deemed an original, but all
        together shall constitute one and the same instrument.

18.     Except as expressly modified by this Amendment, all terms and conditions
        of the International Agreement shall remain in full force and effect.





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        IN WITNESS WHEREOF, each of the parties hereto has caused this Amendment
to be executed by its duly authorized representative as of the day and year
first above written.


ABBOTT INTERNATIONAL, LTD.                SONUS PHARMACEUTICALS, INC.


By:    /s/ Richard A. Gonzalez            By:    /s/ Michael A. Martino
       -----------------------------             -----------------------------
Title: President, Hospital Products       Title: President
       Division


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                                  APPENDIX 5.2

                           MILESTONE AND LICENSE FEES
                                PAYMENT SCHEDULE




                                                        
1.     Execution of Definitive Agreement                       US$ 1 million

2.     Filing of NDA with EMEA                                 US$ 1 million 
          within 15 days

3.     Commencement of Phase III Myocardial Perfusion Studies*
          within 30 days                                       US$ 1 million
          within 120 days                                          1 million
          within 150 days                                          1 million

4.     United States NDA Approval
          within 15 days                                       US$ 3 million***

5.     European Community Marketing Authorization Granted
          within 15 days                                       US$ 2 million
          within 105 days                                          1 million***
          within 195 days                                          1 million***

6.     First Shipment Date of Product for Sale** 
          within 15 days                                       US$ 3 million***
          within 105 days                                          1 million***




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7.     Annual**** (One-Time)  U.S. $20 Million Net Sales in the
          Territory                                            US$ 4 million

8.     Annual**** (One-Time) U.S. $40 Million Net Sales in the
          Territory                                            US$ 2 million

       Total License and Milestone Payments                    US$ 22 million



*"Commencement" means enrollment of first patient in a U.S. clinical study.

**To Germany, France, Italy, Spain, Canada or the United Kingdom.

***These milestone payments shall be earned based on approved indications. Of
the amount specified in item 4 above, fifty percent (50%) shall be earned based
on United States NDA approval by the FDA of the Cardiology Indication for the
Product, and fifty percent (50%) shall be earned based on United States NDA
approval by the FDA of the Radiology Indication or a radiology indication
mutually agreed by the parties hereafter for the Product. Of the amounts
specified in items 5 and 6 above, fifty percent (50%) shall be earned based on
approval by the EMEA of the Cardiology Indication for the Product, and fifty
percent (50%) shall be earned based on approval by the EMEA of the Radiology
Indication or of a radiology indication mutually agreed by the parties hereafter
for the Product.

****"Annual" means the then-applicable fiscal year of ABBOTT.





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                                  APPENDIX 5.3


                 OFFSETTABLE MILESTONES, LICENSE AND OPTION FEES
                                PAYMENT SCHEDULE


                                                        
1.     Execution of Definitive Agreement
          within 300 days                                      US$ 700,000

2.     Commencement of Phase III Myocardial Perfusion Studies*
          within 30 days                                       US$ 700,000 
          within 120 days                                          700,000

3.     After Exercise by ABBOTT of Article 5.1 (C) Option
          On December 15, 1997                                 US$ 1,400,000 
          On January 15, 1998                                        700,000
          On April 15, 1998                                          700,000

4.     European Community Marketing Authorization Granted
          within 15 days                                       US$ 700,000 
          within 105 days                                          700,000** 
          within 195 days                                          700,000** 
          within 265 days                                          700,000**





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5.     Annual*** (One-Time) U.S. $20 Million Net Sales in the 
          Territory                                            US$ 2,800,000

6.     Annual*** (One-Time) U.S. $40 Million Net Sales in the
          Territory                                            US$  2,100,000

       Total Offsettable License and Milestone Payments        US$ 12,600,000



* "Commencement" means enrollment of first patient in a U.S. clinical study.

** These milestone payments shall be earned based on approved indications. Fifty
percent (50%) shall be earned based on approval by the EMEA of the Cardiology
Indication for the Product, and fifty percent (50%) shall be earned based on
approval by the EMEA of the Radiology Indication or a radiology indication
mutually agreed by the parties hereafter for the Product.

*** "Annual" means the then-applicable fiscal year of ABBOTT.









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                                  APPENDIX 6.1

                                  ROYALTY RATES




Indications                            Aggregate Annual** Sales          Royalty Rate
- -------------------------------        --------------------------        ----------------
                                                                  
Sales during the period that           Up to $42 million                 24% of Net Sales
there is only Cardiology                                              
Indication approved in the E.U.*                                      
                                                                      
Sales during the period that           Greater than $42 million          28% of Net Sales
there is only Cardiology                                              
Indication approved in the E.U.*                                      
                                                                      
Sales during the period that           Up to $90 million                 28% of Net Sales
there are Cardiology and                                              
Radiology Indications approved                                        
in the E.U.*                                                          
                                                                      
Sales during the period that           From $90 million to $125          32% of Net Sales
there are Cardiology and               million                        
Radiology Indications approved                                        
in the E.U.*                                                          
                                                                      
Sales during the period that           Over $125 million                 36% of Net Sales
there are Cardiology and                                              
Radiology Indications approved                                        
in the E.U.*                                                          
                                                                      
Sales during the period that           Up to $90 million                 32% of Net Sales
there are Cardiology, Radiology                                       
and perfusion Indications                                             
approved in the E.U.*                                                 
                                                                      
Sales during the period that           From $90 million to $125          36% of Net Sales
there are Cardiology, Radiology        million                        
and perfusion Indications                                             
approved in the E.U.*                                                 
                                                                      
Sales during the period that           From $125 million to $225         40% of Net Sales
there are Cardiology, Radiology        million                        
and perfusion Indications                                             
approved in the E.U.*                                                 
                                                                      
Sales during the period that           Over $225 million                 42% of Net Sales
there are Cardiology, Radiology                                       
and perfusion Indications                                             
approved in the E.U.*                                                 






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* "Approved in the E.U." means that EMEA marketing authorization has been
obtained for the specified indications in at least Germany, France, Italy, Spain
and the United Kingdom.










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