Anesiva, Inc. Initiates New Phase 2 Trial of Adlea(TM) for Pain Relief Following Knee Replacement Surgery

SOUTH SAN FRANCISCO, Calif., Sept. 13 /PRNewswire-FirstCall/ -- Anesiva, Inc. today announced that it has initiated a new Phase 2 study of Adlea(TM) (formerly 4975) for the relief of post-operative pain in patients undergoing total knee replacement surgery, also called total knee arthroplasty (TKA). Adlea is a long-acting, non-opiate analgesic drug designed to provide pain relief for weeks to months after a single local administration during the surgical procedure.

"Given the positive preliminary results from our studies of Adlea in a number of clinical settings, we believe that Adlea offers a unique profile of powerful pain reduction without the side effects common to many medicines for moderate to severe pain," said John P. McLaughlin, chief executive officer of Anesiva. "In total knee replacement surgery, up to 80 percent of these patients will experience moderate to severe pain following this surgery with current pain medications as well as the side effects associated with those pain medicines, such as vomiting, nausea and sedation. We believe Adlea may offer significant and continuous lasting relief from the moderate to severe pain that commonly follows this procedure. We look forward to obtaining additional results in this indication."

Previously, the company successfully studied a 5mg dose of Adlea in patients who had completed total knee replacement. The new trial will evaluate a higher dose of Adlea-15mg-relative to 5mg and placebo in a double-blind, multi-center study of approximately 80 TKA patients. This 15mg dose equates to a higher drug concentration that has shown significant analgesic efficacy in other clinical settings.

Anesiva's goal is to initiate other clinical trials of Adlea for two lead indications in the coming months: management of acute post-operative pain associated with orthopedic surgeries and management of osteoarthritis pain in the knee. These include a Phase 2 trial in total hip replacement, a Phase 2 trial in arthroscopic shoulder surgery, a Phase 2 / 3 trial in osteoarthritis of the knee and a Phase 3 trial in TKA.

How Adlea May Provide Long-Duration, Well-Tolerated Pain Relief

Adlea is long-acting, with the potential to provide pain relief for weeks or months after just a single localized treatment. It is a non-opiate TRPV1 agonist with a unique mechanism of action that provides a long-lasting, localized effect on C-fibers and blocks the transmission of aching, throbbing pain caused by major surgical procedures and end-stage osteoarthritis. Because it selectively acts on pain-sensing nerve endings, Adlea does not affect other nerve fibers necessary for sensory or motor sensations, such as those needed to sense temperature or pressure. In clinical studies to date, the prolonged analgesic effect of Adlea does not seem to be associated with the systemic side effects commonly associated with NSAIDs (gastrointestinal and renal toxicities, and impaired clotting), COX-2 inhibitors (cardiovascular risks and renal toxicity), or opiates (respiratory depression, nausea/vomiting, sedation, disorientation, physical dependence, and the risk of addiction).

About Total Knee Arthroplasty

Total knee replacement (also known as total knee arthroplasty) is generally performed in patients with end-stage osteoarthritis of the knee. These patients have disabling pain which imposes severe limitations on their mobility, and knee replacement is performed with the goal of restoring or improving patients' quality of life. There were an estimated 470,000 total knee replacement procedures performed in the United States in 2005, and the number of replacements will continue to grow as the average age of the U.S. population increases and as these individuals conduct more active lives. The American Academy of Orthopedic Surgery projects that approximately 3.5 million of these procedures will be done each year by 2030.

About Anesiva and its Diverse Portfolio of Pain Products

Anesiva, Inc. is a late-stage biopharmaceutical company that seeks to be the leader in the development and commercialization of novel therapeutic treatments for pain. The company has one FDA-approved product, Zingo(TM) (lidocaine hydrochloride monohydrate) powder intradermal injection system, to reduce pain associated with peripheral venous access procedures in children three to 18 years of age. The second product in Anesiva's pipeline, Adlea(TM) (formerly 4975), has been shown to reduce pain after only a single administration for weeks to months in multiple settings in numerous mid-stage clinical trials for site-specific, moderate-to-severe pain. Anesiva is based in South San Francisco, CA. For more information about Anesiva's leadership in the development of products for pain management, and an overview of the clinical challenges being addressed by its product candidates, go to http://www.anesiva.com.

Forward Looking Statements

This press release includes "forward-looking statements" within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. Words such as "expect," "estimate," "project," "budget," "forecast," "anticipate," "intend," "plan," "may," "will," "could," "should," "believes," "predicts," "potential," "continue," and similar expressions are intended to identify such forward-looking statements. Forward-looking statements in this press release include matters that involve known and unknown risks, uncertainties and other factors that may cause actual results, levels of activity, performance or achievements to differ materially from results expressed or implied by this press release. Such risk factors include, among others: the timing and results of our clinical trials, whether Adlea will ultimately prove to be safe and effective in TKA and other indications, whether Anesiva can commercially release new products successfully and the degree to which these products gain market acceptance. Actual results may differ materially from those contained in the forward-looking statements in this press release. Additional information concerning these and other risk factors is contained in Anesiva's quarterly report on Form 10-Q for the quarter ended June 30, 2007.

Anesiva undertakes no obligation and does not intend to update these forward-looking statements to reflect events or circumstances occurring after this press release. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement.

CONTACT: Paul Goodson, Sr. Dir., Investor Relations of Anesiva, Inc.,+1-650-246-6898, investors@anesiva.com

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