First Multiple Dose Clinical Trial of TorreyPines Therapeutics, Inc. Oral Compound NGX426 Demonstrates Compound Is Safe and Well-Tolerated

Findings Support Development for Chronic Pain Indications

LA JOLLA, Calif., Feb. 11 /PRNewswire/ -- TorreyPines Therapeutics, Inc. today announced that oral administration of NGX426, an AMPA/kainate-type glutamate receptor antagonist, was safe and well-tolerated in healthy male and female subjects when dosed once daily for five consecutive days.

“The successful completion of this Phase I trial demonstrating the safety and tolerability of NGX426 when dosed over multiple days provides support for pursuing a Phase II program in chronic indications,” said Ev Graham, Chief Executive Officer of TorreyPines. “Combined with the positive results from our recently completed Phase I study of NGX426 in a capsaicin induced pain model, we are very encouraged about the potential for NGX426 to treat both acute and chronic pain conditions.”

The Phase I double-blind, placebo-controlled trial enrolled 20 healthy male and female subjects in sequential, dose-escalating cohorts. Subjects received once-daily oral doses of either 90 mg or 150 mg of NGX426 or placebo for five consecutive days, approximating exposure under steady-state pharmacokinetic conditions. Overall, NGX426 was well-tolerated. There were no dose-limiting adverse events or discontinuations from the study and reported adverse events were generally mild and transient.

NGX426, an ester prodrug, is an oral form of tezampanel, TorreyPines most advanced product candidate. Pharmacokinetic analyses from two Phase I studies confirmed that when given to humans, NGX426 is rapidly converted to tezampanel, the active moiety. To date, six Phase II, double-blind, placebo-controlled trials have demonstrated that tezampanel, administered either subcutaneously or intravenously, was more effective than placebo in relieving pain across migraine, nociceptive and neuropathic pain models, including a capsaicin-induced pain model. In December 2008, TorreyPines announced that NGX426 demonstrated a statistically significant reduction in spontaneous pain, hyperalgesia (abnormally increased pain state) and allodynia (pain resulting from normally non-painful stimuli to the skin) compared to placebo following intradermal injections of capsaicin in a human experimental model of cutaneous pain, hyperalgesia and allodynia.

In order to pursue the Phase II clinical development of NGX426, TorreyPines intends to explore financing and strategic alternatives, including a possible project financing, equity financing, partnership, asset out-licensing or sale of the company.

About TorreyPines Therapeutics, Inc.

TorreyPines Therapeutics, Inc. is a biopharmaceutical company committed to providing patients with better alternatives to existing therapies through the research, development and commercialization of small molecule compounds. The company’s goal is to develop versatile product candidates each capable of treating a number of acute and chronic diseases and disorders such as migraine, chronic pain, muscle spasticity, xerostomia and cognitive disorders. The company is currently developing three product candidates: two ionotropic glutamate receptor antagonists and one muscarinic receptor agonist. Further information is available at www.torreypinestherapeutics.com.

This press release contains forward-looking statements or predictions. Such forward-looking statements include, but are not limited to, statements regarding the potential for NGX426 as a treatment for clinical pain states, including the potential for NGX426 as a treatment for neuropathic pain and acute migraine, and the ability for TorreyPines to successfully complete a strategic or financing transaction. Such statements are subject to numerous known and unknown risks, uncertainties and other factors, which may cause TorreyPines’ actual results to be materially different from historical results or from any results expressed or implied by such forward-looking statements, including whether experimental pain models of pain, including the capsaicin model, are accurate in predicting efficacy of novel analgesics in early clinical trials, whether the results of any Phase II trial or other study of NGX426 will be consistent with the results of the study reported in this press release, whether TorreyPines will be able to complete any potential strategic or financing transaction on terms acceptable to TorreyPines’ stockholders, how the volatile economic environment will affect TorreyPines’ efforts to complete a strategic or financing transaction, whether TorreyPines’ cash resources will be sufficient to fund operations as planned, whether any preclinical studies or clinical trials, either ongoing or conducted in the future, will prove successful, and if successful, whether the results can be replicated; whether safety and efficacy profiles of any of the company’s product candidates will be established, or if established, will remain the same, be better or worse in future clinical trials, if any; whether pre-clinical results will be substantiated by ongoing or future clinical trials, if any, or whether any of the company’s product candidates will be able to improve the signs or symptoms of their respective clinical indication; whether any of the company’s product candidates will support a filing for marketing approval, will be approved by the regulatory authorities, or if approved, will prove competitive in the market; or whether the necessary financing to support the company’s product development programs will be available. In particular there is no guarantee that clinical trials of any of the company’s product candidates will be completed on schedule or that results of these clinical trials will be reported within the anticipated timeframe, that NGX426 will successfully treat migraine, neuropathic pain and/or other indications for which it is developed, or that TorreyPines will be able to complete the necessary development work and receive regulatory approval for NGX426. These and other risks which may cause results to differ are described in greater detail in the “Risk Factors” section of TorreyPines’ annual report on Form 10-K for the year ended December 31, 2007 and TorreyPines other SEC reports. The forward-looking statements are based on current information that is likely to change and speak only as of the date hereof.

CONTACT: Paul Schneider of TorreyPines Therapeutics, Inc.,
+1-858-623-5665, ext. 125, pschneider@tptxinc.com; or Investor, Rhonda
Chiger of Rx Communications Group, +1-917-322-2569, rchiger@rxir.com, for
TorreyPines Therapeutics, Inc.

Web site: http://www.torreypinestherapeutics.com/

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