Sonus Pharmaceuticals Ends Discovery Efforts of Two Programs and Reduces its Headcount

Sonus Pharmaceuticals Ends Discovery Efforts of Two Programs and Reduces its Headcount

3/25/2008

BOTHELL, Wash., March 25, 2008 -- Sonus Pharmaceuticals today announced that it has focused its efforts on the clinical development of SN2310 and on broadening and deepening its pipeline of clinical drug candidates through external initiatives. As a result of this decision, the Company has ended its internal discovery efforts in two small molecule oncology programs and further reduced its headcount and quarterly cash burn.

``After a careful and thorough review of our internal initiatives and the existing capital market environment, we've decided to focus our efforts on the continued development of SN2310, our Phase 1 clinical compound, and on expanding our drug candidate pipeline through external initiatives, including in-licensing and strategic transactions,'' said Michael A. Martino, President and Chief Executive Officer of Sonus Pharmaceuticals. ``Our two discovery programs had promising potential, and the team had made encouraging progress in a relatively short period of time. However, the potential returns on those programs were long-term, and we have made a strategic decision to focus on initiatives designed to provide us with drug candidates whose potential could be realized in a much shorter timeframe than any developed through the internal discovery program. Our decision was a difficult one to make and reduces our workforce by 16 employees,'' he added.

As a result of the decision to end the internal discovery effort, the Company now believes it has sufficient cash to fund operations into the fourth quarter of 2009.

About Sonus Pharmaceuticals

Headquartered near Seattle, Washington, Sonus Pharmaceuticals, Inc. is focused on the development of cancer drugs that are designed to provide better efficacy, safety and tolerability, and ease of use. Sonus moved an oncology product candidate, SN2310, into a Phase 1 clinical trial in September 2006. For additional information on Sonus, including past news releases, please visit http://www.sonuspharma.com.

Safe Harbor

Certain statements made in this press release are forward-looking such as those, among others, relating to the development, safety and efficacy of therapeutic drugs and potential applications for these products. As discussed in Sonus Pharmaceuticals' filings with the Securities and Exchange Commission, including its Annual Report on Form 10-K for 2007, actual results could differ materially from those projected in the forward-looking statements as a result of the following factors, among others: the Company's products will require extensive clinical testing and approval by regulatory authorities; such approvals are lengthy and expensive and may never occur; risks that the Phase 1 clinical trial for SN2310 will not be successful; risks that the Company may not be successful in obtaining funding from third parties or completing a financing necessary to support the costs and expenses of clinical studies and related development activities; and risks that external strategic initiatives may not be available on acceptable terms, or even if available, may not be consummated. The Company undertakes no obligation to update the forward-looking statements contained herein or to reflect events or circumstances occurring after the date hereof.