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Treatment for Insomnia

Update: Silenor Now FDA Approved - March 17, 2010

FDA Complete Response Letter for Silenor (doxepin)

Somaxon Receives Complete Response Letter from the FDA for Silenor (doxepin)

SAN DIEGO--(BUSINESS WIRE)--Feb 26, 2009 - Somaxon Pharmaceuticals, Inc., a specialty pharmaceutical company focused on the in-licensing, development and commercialization of proprietary product candidates for the treatment of diseases and disorders in the central nervous system therapeutic area, today announced that the company has received a Complete Response Letter from the U.S. Food and Drug Administration (FDA) for its New Drug Application (NDA) for Silenor (doxepin) for the treatment of insomnia. Based on its review, the FDA has determined that the NDA cannot be approved in its present form.

In the Complete Response Letter the FDA raised a number of issues relating to the interpretation of the efficacy data contained in the Silenor NDA and indicated that the FDA was open to a discussion of these concerns. The FDA did not specifically request the company to conduct additional clinical trials of Silenor. The company believes that a discussion with the FDA will be necessary to gain a complete understanding of the implications of the issues raised in the Complete Response Letter, and the company intends to schedule this discussion as soon as possible.

With respect to safety, the FDA noted that there were no adverse events observed in the clinical studies included in the NDA that would preclude approval, but asked the company to address the possibility that doxepin may prolong the cardiac QT interval. The company intends to respond by submitting to the FDA the results of its completed clinical trial of doxepin that evaluated the potential for electrocardiogram effects. As the company has previously disclosed, the results of this clinical trial demonstrated that doxepin had no effect on QT interval prolongation when administered at 6 mg or 50 mg.

"We continue to believe that the data in the NDA we have submitted, together with the QT data we will submit, is sufficient to support a determination by the FDA that Silenor can be approved for the treatment of insomnia," said Richard W. Pascoe, Somaxon's president and chief executive officer. "We are committed to working with the FDA to resolve the issues raised in the Complete Response Letter so that Silenor can be approved. As we continue to seek approval of Silenor, we will continue to take measures to conserve our cash and will evaluate financing alternatives available to us."

About Silenor

Silenor is a low-dose (1 mg, 3 mg, 6 mg) oral tablet formulation of doxepin hydrochloride that is patent protected for use in insomnia. Physicians have prescribed doxepin for more than 35 years for the treatment of depression and anxiety at dosages typically ranging from 75 mg to 300 mg per day. Based upon the controlled clinical trials of Silenor completed by Somaxon, the company believes that Silenor may be well tolerated by patients. In addition, the FDA has indicated that it will recommend that Silenor not be scheduled as a controlled substance.

About Somaxon Pharmaceuticals, Inc.

Headquartered in San Diego, CA, Somaxon Pharmaceuticals, Inc. is a specialty pharmaceutical company focused on the in-licensing, development and commercialization of proprietary product candidates for the treatment of diseases and disorders in the central nervous system therapeutic area. A New Drug Application (NDA) for Silenor (doxepin), Somaxon's drug candidate for insomnia, has been filed with the U.S. Food and Drug Administration and currently is under review.

For more information, please visit the company's web site at

Somaxon cautions you that statements included in this press release that are not a description of historical facts are forward-looking statements. For example, statements regarding the review process for the NDA and the potential approval of the NDA for Silenor are forward looking statements. The inclusion of forward-looking statements should not be regarded as a representation by Somaxon that any of its plans will be achieved. Actual results may differ materially from those set forth in this release due to the risks and uncertainties inherent in Somaxon's business, including, without limitation, Somaxon's interpretation of the Complete Response Letter, and the FDA's agreement with such interpretation; the potential for Silenor to receive regulatory approval for one or more indications on a timely basis or at all; the potential for the FDA to impose non-clinical, clinical or other requirements to be completed before or after regulatory approval of Silenor; Somaxon's ability to demonstrate to the satisfaction of the FDA that potential NDA approval of Silenor is appropriate prior to the completion of standard, long-term carcinogenicity studies, given the context of completed trials and pending studies; the timing and results of non-clinical studies for Silenor, and the FDA's agreement with Somaxon's interpretation of such results; Somaxon's ability to raise sufficient capital to meet FDA requirements and otherwise fund its operations, and to meet its obligations to parties with whom it contracts relating to financing activity, and the impact of any such financing activity on the level of Somaxon's stock price; the impact of any inability to raise sufficient capital to fund ongoing operations, including the potential to be required to restructure the company or to be unable to continue as a going concern; Somaxon's ability to successfully commercialize Silenor, if it is approved by the FDA; the potential to enter into and the terms of any strategic transaction relating to Silenor; the scope, validity and duration of patent protection and other intellectual property rights for Silenor; whether any approved label for Silenor is sufficiently consistent with such patent protection to provide exclusivity for Silenor; Somaxon's ability to operate its business without infringing the intellectual property rights of others; unexpected findings relating to Silenor that could delay or prevent regulatory approval or commercialization, or that could result in recalls or product liability claims; other difficulties or delays in development, testing, manufacturing and marketing of and obtaining regulatory approval for Silenor; the market potential for insomnia treatments, and Somaxon's ability to compete within that market; and other risks detailed in Somaxon's prior press releases as well as in its periodic filings with the Securities and Exchange Commission.

You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement and Somaxon undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof. This caution is made under the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934.

Contact: Investor Inquiries
Somaxon Pharmaceuticals, Inc.
Meg McGilley
Chief Financial Officer
PondelWilkinson, Inc.
Rob Whetstone
Media Inquiries
BioComm Network
Blake Sweat

Posted: February 2009

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