EXHIBIT 99.1
NEWS RELEASE


          SONUS ANNOUNCES THE FDA HAS REQUESTED ADDITIONAL INFORMATION
                      REGARDING THE ECHOGEN(R) NDA REVIEW


          COMPANY EXPECTS RESPONSE TO LEAD TO APPROVABILITY BY THE FDA

BOTHELL, WASH., February 26, 1998 -- SONUS Pharmaceuticals, Inc. (Nasdaq-NNM:
SNUS), today announced that the Company has received notice from the U.S. Food
and Drug Administration (FDA) that approval of the EchoGen(R) New Drug
Application (NDA) requires additional information. The Company expects to be
able to provide completely all of the requested information. EchoGen(R) is the
Company's proprietary fluorocarbon-based ultrasound contrast agent being
investigated to improve ultrasound images for cardiology and radiology.

SONUS received official notice that the FDA has completed its review of the
EchoGen(R) NDA and has asked the Company to provide additional information
relating to the manufacturing processes, including chemistry and analytical
methods validation, and to provide a re-analysis of some of the animal and
clinical data. None of the FDA's questions or requests for data are related to
the clinical safety of the product as reflected in the clinical trials with
EchoGen(R). The Company will be providing these data to the FDA to allow
completion of the review by the FDA. Once the issues are addressed to the FDA's
satisfaction, SONUS anticipates that the FDA's final determination will be
positive.

"Based on substantial additional clinical and pre-clinical work completed since
the NDA was filed, we believe we can complete assembly of the information that
the FDA has requested within a few weeks, although this period could be extended
due to circumstances we cannot directly control," said Steven C. Quay, M.D.,
Ph.D., president and CEO of SONUS. "Some of the data requires re-analysis, which
is underway at this time, and all of our efforts are focused on quickly
responding to all remaining issues."

SONUS Pharmaceuticals, Inc., based in Bothell, Wash., is engaged in the research
and development of ultrasound contrast agents and drug delivery systems based on
its proprietary PhaseShift(TM) and fluorocarbon technology. The Company's
products are being investigated to improve the diagnosis and treatment of heart
disease, cancer and other debilitating conditions.


                                     -More-


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SONUS PHARMACEUTICALS, INC. - RECEIVES NOTICE FROM FDA
FEBRUARY 26, 1998
PAGE TWO



Contact:       Investors                           Media
               Gregory Sessler                     Kelly Ford
               SONUS Pharmaceuticals, Inc.         SONUS Pharmaceuticals, Inc.
               (425) 487-9500                      (425) 487-9500

Certain of the statements made in this news release are forward looking such as
those relating to the regulatory approval of EchoGen(R). As discussed in SONUS'
annual report on Form 10-K filed March 19, 1997, actual results could differ
materially from those projected in the forward-looking statements as a result of
the following factors, among others: EchoGen(R) will require regulatory
approval, which approval is subject to certain regulatory requirements and can
be lengthy and may include additional requests by the FDA; and market acceptance
of EchoGen(R) will depend on a number of factors, including safety, efficacy,
ease of administration and the presence of competitive imaging products or
technologies. There can be no assurance that the FDA will approve EchoGen(R).

NOTE: SONUS Pharmaceuticals' press releases are available via PR Newswires'
Company News on Call service. To receive previous SONUS press releases via fax,
dial 1-800-758-5804, ext. 108377. SONUS releases also can be accessed on the
Internet at http://prnewswire.com. Additional information about SONUS can be
accessed at the SONUS Home Page, http://www.sonuspharma.com.



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