Watson Pharmaceuticals, Inc., a leading specialty pharmaceutical company, announced that it received a Complete Response Letter from the US Food and Drug Administration (FDA) on its New Drug Application (NDA) for Trelstar 22.5 mg (triptorelin pamoate for injectable suspension), a 24-week formulation of Trelstar for the palliative treatment of advanced prostate cancer. The Trelstar NDA was prepared in cooperation with Debiopharm Group, a Swiss-based global biopharmaceutical group of companies.

According to the letter, the FDA has requested clarifications related to the clinical testing of the product, additional information regarding the chemistry, manufacturing and controls (CMC) of the product and other components, and information related to third party manufacturing. Watson is working to ensure the requested information is provided to the FDA expeditiously.

Trelstar 22.5 mg builds on Watson's long-standing track record in prostate cancer and expanding urology franchise. The new, longer-acting formulation of Trelstar is designed to be conveniently administered and to continuously suppress the production of testosterone in men with advanced prostate cancer for 24 weeks. Trelstar is an already proven therapy with established efficacy and safety in two formulations - a four-week formulation (Trelstar Depot) and a 12-week formulation (Trelstar LA).

Trelstar, developed by Debiopharm Group and marketed by Watson, administers a synthetic luteinizing hormone releasing hormone (LHRH) agonist, triptorelin, which suppresses the production of testosterone in the testicles. Prostatic cancer proliferation is regulated in part by the level and activity of testosterone. Trelstar is currently available in a four-week depot formulation (Trelstar Depot) and a 12-week long-acting formulation (Trelstar LA), offering an alternative treatment for prostate cancer when orchiectomy (removal of the testicles) or estrogen administration are either not indicated or unacceptable to the patient. Trelstar does not require refrigeration and should be stored at controlled room temperature.

Watson Pharmaceuticals, Inc., is a global leader in the development and distribution of pharmaceuticals with a broad portfolio of generic products and a specialized portfolio of brand pharmaceuticals focused on Urology, Women's Health and Nephrology/Medical.

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.