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FDA Approves Trelstar 22.5 mg

FDA Approves Watson's Trelstar 22.5 mg, the First and Only 6-Month Intramuscular GnRH Agonist for the Palliative Treatment of Advanced Prostate Cancer

MORRISTOWN, N.J., March 11 /PRNewswire-FirstCall/ -- Watson Pharmaceuticals, Inc., today announced the U.S. Food and Drug Administration (FDA) approval of Trelstar 22.5 mg (triptorelin pamoate for injectable suspension), a new twice-yearly formulation of Trelstar, a proven, simple and effective palliative treatment of advanced prostate cancer. With an anticipated May launch, Trelstar 22.5 mg is the first and only six-month intramuscular (IM) GnRH agonist available for the palliative treatment of advanced prostate cancer. Trelstar 22.5 mg is also the only six-month GnRH agonist that is stored at room temperature; no refrigeration is required.

Trelstar 22.5 mg releases triptorelin pamoate, a gonadotropin releasing hormone (GnRH) agonist, over a prolonged period and, in turn, suppresses testosterone production for six months. Developed by Debiopharm Group and first approved in the U.S. in 2000, Trelstar is indicated for the palliative treatment of advanced prostate cancer and is currently available in one-month (3.75 mg) and three-month (11.25 mg) forms. The new, longer-acting six-month formulation is designed to provide patients and physicians with a more convenient therapeutic option that is well tolerated and as effective.

Trelstar is administered via the MIXJECT® delivery system, which utilizes a thin (21-gauge) needle, and thereby offers easy administration with low incidence of injection site pain. In fact, in the clinical trial, only 1.7% of patients reported injection site pain. Following administration, the MIXJECT® needle is captured to help comply with OSHA regulations.

"Trelstar 22.5 mg builds on our extensive and established urology portfolio, and the forthcoming May launch will mark another critical milestone in the growth of our Brand business," said Fred Wilkinson, Executive Vice President, Global Brands at Watson. "We are confident that the unique combination of convenience, reliable testosterone and PSA suppression, and injection site tolerability of this longer-acting Trelstar formulation will provide advanced prostate cancer patients and their physicians an important treatment option. In fact, we plan to further evaluate and quantify the unique injection site tolerability this product offers as compared to other commonly used GnRH agonists later this year."

The approval is based on a 12-month (48 week) phase 3 study evaluating the efficacy, pharmacokinetics, and safety of Trelstar 22.5 mg administered every six months (24 weeks) in patients with advanced prostate cancer. Over the study, Trelstar 22.5 mg produced a mean testosterone serum level of 12.8 ng/dL from month two through month 12, well below castration levels associated with androgen deprivation therapy. By day 29, 97.5% of the clinical trial patients achieved castrate level, and >98% of all patients were below castrate level at month six and month 12. Median prostate specific antigen (PSA) was also reduced by 96.4% at the end of the study. The most commonly reported adverse events associated with the use of Trelstar 22.5 mg included hot flushes (71.7%), erectile dysfunction (10.0%), and testicular atrophy (7.5%).

About Prostate Cancer

Prostate cancer is the most common cancer among men in the U.S. and causes approximately 27,000 U.S. male fatalities each year. As of 2009, more than two million men in this country were estimated to be living with prostate cancer, and the National Cancer Institute estimates that nearly 200,000 men were diagnosed in the U.S. alone in 2009. The U.S. market for the palliative treatment of advanced prostate cancer is defined by the use of GnRH agonists and antagonists.

Important Safety Information

The most commonly reported adverse events associated with the use of Trelstar 22.5 mg included hot flushes (71.7%), erectile dysfunction (10.0%), and testicular atrophy (7.5%). The most commonly reported adverse events associated with the use of Trelstar 3.75 mg/ Trelstar 11.25 mg included hot flushes (58.6%/73.0%), skeletal pain (12.1%/13.2%), impotence (7.1%/2.3%), headache (5.0%/6.9%), leg pain (2.1%/5.2%), and edema in legs (0.0%/6.3%). Trelstar is contraindicated in women who are or may become pregnant as well as patients who are hypersensitive to triptorelin, other GnRH agonists, or GnRH. Anaphylactic shock, hypersensitivity, and angioedema related to triptorelin administration have been reported. Trelstar causes an initial transient increase in testosterone levels. Patients may experience the onset or exacerbation of symptoms during this period, including bone pain, neuropathy, hematuria, spinal cord compression, or urethral or bladder outlet obstruction. Patients with metastatic vertebral lesions and/or urinary tract obstruction should be closely observed.

About Watson Pharmaceuticals, Inc.

Watson Pharmaceuticals, Inc., is a leading global specialty pharmaceutical company. The Company is engaged in the development and distribution of generic pharmaceuticals and specialized branded pharmaceutical products focused on Urology and Women's Health. Watson has operations in many of the world's established and growing international markets.

In the U.S., the Watson brand portfolio includes RAPAFLO, GELNIQUE, Oxytrol, Trelstar 3.75 mg and Trelstar 11.25 mg and INFeD. In addition, Watson markets the following brands under co-promotion agreements: AndroGel, with Solvay Pharmaceuticals, Inc., and Femring, with Warner Chilcott Limited. The Watson brand pipeline portfolio includes a number of products, including URACYST, under development for cystitis; and three novel new contraceptives.

For press release and other company information, visit Watson Pharmaceuticals' Web site at http://www.watson.com/.

About Debiopharm Group

Debiopharm Group is a Swiss-based global biopharmaceutical group of companies with a focus on the development of prescription drugs that target unmet medical needs. The group in-licenses promising biological and small molecule drug candidates. It develops its products for global registration and maximum commercial potential. Once registered, the products are out-licensed to pharmaceutical partners for sales and marketing.

Debiopharm independently funds the worldwide development of all of its products while providing expertise in pre-clinical and clinical trials, manufacturing, drug delivery and formulation, and regulatory affairs.

Founded in 1979 and headquartered in Lausanne, Switzerland, Debiopharm has developed four products with global combined sales of $2.6 billion in 2008.

For more information on Debiopharm Group, please visit: www.debiopharm.com

MIXJECT® is a registered trademark of Medimop Medical Projects Ltd. All other trademarks are property of their respective owners.

Forward-Looking Statement

Statements contained in this press release that refer to non-historical facts are forward-looking statements that reflect Watson's current perspective of existing information as of the date of this release. For example, any statements in this press release concerning future approvals or other events related to products or future products and Watson's strategic initiatives and business plans are forward-looking statements. It is important to note that Watson's goals and expectations are not predictions of actual performance. Actual results may differ materially from Watson's current expectations depending upon a number of factors affecting Watson's business. These factors include, among others, the impact of competitive products and pricing; timely and successful consummation and implementation of strategic initiatives; the timing and success of product launches; the difficulty of predicting the timing or outcome of product development efforts and FDA or other regulatory agency approvals or actions; costs and efforts to defend or enforce intellectual property and contractual rights; difficulties or delays in manufacturing; the availability and pricing of third party sourced products and materials; successful compliance with FDA and other governmental regulations applicable to Watson their third party manufacturers' facilities, products and/or businesses; changes in the laws and regulations, including Medicare and Medicaid, affecting among other things, pricing and reimbursement of pharmaceutical products; and such other risks and uncertainties detailed in Watson's periodic public filings with the Securities and Exchange Commission, including but not limited to Watson's annual report on Form 10-K for the year ended December 31, 2009. Except as expressly required by law, Watson disclaims any intent or obligation to update these forward-looking statements.

Posted: March 2010

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