Auxilium Pharmaceuticals, Inc. a specialty biopharmaceutical company, announced it has reached the target enrollment for the double-blind placebo-controlled phase III programme of Xiaflex for the treatment of Peyronie's disease. In accordance with the study design, all enrolled patients will have received their first injection of either Xiaflex or placebo by the end of March 2011.

The company will exceed its enrollment target of 600 patients. Peyronie's disease is the development of a collagen plaque on the penis that can cause the penis to curve during erection, often interfering with or preventing intercourse and resulting in psychological distress or bother for the patient.

“We are very pleased to achieve this important development milestone in Peyronie's disease and advance what can potentially be a second indication for Xiaflex,” said Armando Anido, CEO and president of Auxilium. “We believe completing the enrollment of over 600 patients at sites in the US and Australia in less than six months speaks to the enthusiasm in the urology community and their prospective patients for a non-surgical treatment alternative. We anticipate reporting top-line results in the first half of 2012.”

The late stage global development plan for Xiaflex for Peyronie's disease consists of four clinical studies and is known by the acronym Impress - The Investigation for Maximal Peyronie's Reduction Efficacy and Safety Studies. The two randomized, double-blind, placebo-controlled phase III studies enrolled a total of over 600 patients at approximately 70 sites in the US and Australia, with a 2:1 ratio of Xiaflex to placebo.

There is also one open label study, which is expected to enroll approximately 250 patients, at approximately 30 sites in the US, EU and New Zealand, and one pharmacokinetic study, which should enroll approximately 16 patients in the US Xiaflex will be administered two times a week every six weeks for up to four treatment cycles (2 x 4). Each treatment cycle will be followed by a penile modelling procedure. Patients will be followed for 52 weeks post-first injection in the double-blind studies and for 36 weeks in the open label trial.

The trials' co-primary endpoints are the mean percent improvement from baseline in penile curvature compared to placebo and the mean change from baseline in the Peyronie's disease bother domain of the Peyronie's Disease Questionnaire (PDQ) compared to placebo.

The PDQ is a proprietary questionnaire that the Company developed with the FDA following our phase II b studies as a valid tool for measuring Peyronie's disease bother. The PDQ also measures severity of psychological and physical symptoms of Peyronie's disease and penile pain. Safety measurements include adverse event monitoring, immunogenicity testing and clinical labs.

“We are encouraged by the clinical profile of Xiaflex, which emerged from our earlier phase II and II b clinical trials in Peyronie's disease,” said James P. Tursi, MD, Auxilium's vice president of Clinical Research & Development. “We believe that our phase III double-blind studies with Xiaflex in Peyronie's disease should provide pivotal evidence that Xiaflex is well-tolerated and produces clinically and statistically significant reductions in both penile curvature and disease bother.”

Peyronie's disease is the development of collagen plaque, or scar tissue, on the shaft of the penis that hardens and reduces flexibility, thus causing pain and forcing the penis to bend or arc during erection. This may prevent intercourse. In addition to difficulty with sexual intercourse, Peyronie's disease may also be associated with emotional distress, bother, loss of self-esteem and depression. Prevalence of Peyronie's disease is estimated to be approximately 5% in adult men, but actual prevalence may be higher, based on autopsies.

Auxilium Pharmaceuticals, Inc. is a specialty biopharmaceutical company with a focus on developing and marketing products to predominantly specialist audiences, such as urologists, endocrinologists, certain targeted primary care physicians, hand surgeons, subsets of orthopaedic, general, and plastic surgeons who focus on the hand, and rheumatologists.