Paladin Labs Inc : PALADIN AND SOMAXON ANNOUNCE FILING OF NEW DRUG SUBMISSION FOR SILENOR(R)

MONTREAL, CANADA and SAN DIEGO, CA - February 22, 2012 ? Paladin Labs Inc. (TSX:PLB) and Somaxon Pharmaceuticals, Inc. (Nasdaq: SOMX) today announced that Paladin has filed a New Drug Submission (NDS) that has been accepted for review by Health Canada for Silenor® (doxepin) for the treatment and symptomatic relief of insomnia.

"We are pleased that Health Canada has accepted to review our submission for Canadian regulatory approval for Silenor®," said Mark Beaudet, interim President and Chief Executive Officer of Paladin Labs Inc. "We believe that Silenor® can fill a significant unmet need in the Canadian insomnia market. To date, the Canadian prescription sleep aid market has consisted mainly of zopiclone, an older medication that, despite its limitations, has driven the market to exceed $87 million in 20111, an increase of 10% vs. 2010."

If approved, Silenor® could be the first and only prescription product approved for the treatment of insomnia in Canada that is not a controlled substance.

Paladin received rights to commercialize Silenor® in Canada, South America and Africa from Somaxon in June 2011. Under the collaboration agreements, there is no payment due to Somaxon from Paladin as a result of the NDS filing. Once Silenor® is commercialized in the licensed territories, Somaxon will be eligible to receive sales-based milestone payments of up to US$128.5 million as well as a tiered double-digit percentage of net sales.

Silenor® is a low-dose (3 mg and 6 mg) oral tablet formulation of doxepin. If approved, Silenor® is expected to be the first and only non-controlled prescription sleep medication in Canada indicated for the treatment and symptomatic relief of insomnia characterized by difficulty in falling asleep, frequent nocturnal awakening and/or early morning awakenings.

Paladin Labs Inc., headquartered in Montreal, Canada, is a specialty pharmaceutical company focused on acquiring or in-licensing innovative pharmaceutical products for the Canadian and select international markets. With this strategy, a focused Canadian national sales team and proven marketing expertise, Paladin has evolved into one of Canada's leading specialty pharmaceutical companies. For more information, please visit the Company's web site at www.paladinlabs.com.

Headquartered in San Diego, CA, Somaxon Pharmaceuticals, Inc. is a specialty pharmaceutical company that sells Silenor ® in the United States. For more information, please visit the company's web site at www.somaxon.com.

1 IMS Health - moving annual total for the 12 months ended December 31, 2011

This press release may contain forward-looking statements and predictions. These forward-looking statements, by their nature, necessarily involve risks and uncertainties that could cause actual results to differ materially from those contemplated by the forward-looking statements. The Company considers the assumptions on which these forward-looking statements are based to be reasonable at the time they were prepared, but cautions that these assumptions regarding the future events, many of which are beyond the control of the Company and its subsidiaries, may ultimately prove to be incorrect. Factors and risks, which could cause actual results to differ materially from current expectations, are discussed in the annual report as well as in the Company's Annual Information Form for the year ended December 31, 20 10. The Company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information or future events and except as required by law. For additional information on risks and uncertainties relating to these forward-looking statements, investors should consult the Company's ongoing quarterly fillings, annual report and Annual Information Form and other fillings found on SEDAR at www.sedar.com.

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 regulatory approval in countries outside the United States and the achievement of milestone payments 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, the market potential for insomnia treatments, and Somaxon's and Paladin Labs' ability to compete within that market; Somaxon's reliance on its collaboration partner, Paladin Labs, and its adherence to the terms of its contract; the timing of receipt of regulatory approval in countries outside of the United States, if at all; Somaxon's ability to successfully enforce its intellectual property rights and defend its patents, including any developments relating to the recent submission of abbreviated new drug applications for generic versions of Silenor 3 mg and 6 mg tablets and related patent litigation; the possible introduction of generic competition of Silenor; the scope, validity and duration of patent protection and other intellectual property rights for Silenor; whether the approved label for Silenor is sufficiently consistent with such patent protection to provide exclusivity for Silenor; Somaxon's ability to successfully commercialize Silenor in the United States; the ability of Somaxon to ensure adequate and continued supply of Silenor to successfully meet anticipated market demand; Somaxon's ability to raise su fficient capital to fund its operations, and the impact of any such financing activity on the level of its stock price; the impact of any inability to raise sufficient capital to fund ongoing operations, including any patent infringement litigation; Somaxon's ability to operate its business without infringing the intellectual property rights of others; inadequate therapeutic efficacy or unexpected adverse side effects relating to Silenor that could result in recalls or product liability claims; other difficulties or delays in development, testing, manufacturing and marketing of Silenor; the timing and results of post-approval regulatory requirements for Silenor, and the FDA's agreement with Somaxon's interpretation of such results and other risks de tailed in Somaxon's prior press releases and periodic filings with the Securities and Exchange Commission.
Readers 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 press 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.

# # #

Samira Sakhia, CA, MBA

Chief Financial Officer

Tel: 514-669-5367

Fax: 514-344-4675

Email: info@paladinlabs.com

Website: www.paladinlabs.com

Tran Nguyen

Chief Financial Officer

(858) 876-6500