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                                                                    EXHIBIT 99.2


                  SECTION 906 CERTIFICATION OF PERIODIC REPORT


I, Richard J. Klein, Chief Financial Officer of Sonus Pharmaceuticals, Inc. (the
"Company"), certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002,
18 U.S.C. Section 1350, that:

(1)   the Annual Report on Form 10-K of the Company for the fiscal year ended
      December 31, 2002 (the "Report") fully complies with the requirements of
      Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C.
      78m or 780(d)); and

(2)   the information contained in the Report fairly presents, in all material
      respects, the financial condition and results of operations of the
      Company.

Dated: March 10, 2003



                                           /s/ Richard J. Klein
                                           -------------------------------------
                                           Richard J. Klein
                                           Chief Financial Officer

