Auxilium Pharmaceuticals, Inc, a specialty biopharmaceutical company, announced top-line efficacy and safety results for the phase-IIb clinical trial for Xiaflex (collagenase clostridium histolyticum) in the treatment of Peyronie's disease. The phase-IIb study was designed to measure efficacy endpoints of improvement in penile curvature and improvement in patients' sexual quality of life using the company's Peyronie's disease Patient Reported Outcome (PRO) questionnaire. Overall, Xiaflex demonstrated a statistically significant change compared to placebo at 36 weeks in both improvement in penile curvature (p=0.001) and the PRO Peyronie's disease bother domain (p=0.046). Xiaflex was well-tolerated and the most common treatment related adverse events in the phase-IIb study were consistent with adverse events reported in previous Peyronie's disease trials with Xiaflex, which included injection site bruising, edema and pain.

"We believe the results from this trial provide a meaningful step forward to a better understanding of the treatment of Peyronie's disease with Xiaflex," said Armando Anido, Auxilium's chief executive officer and president. "We expect to meet with the US FDA in the second quarter of 2010 to discuss a proposed phase-III plan that potentially could be started in the second half of 2010."

The Xiaflex Peyronie's disease phase-IIb trial is one of the largest prospective, randomized, placebo-controlled studies conducted in Peyronie's disease. A total of 145 patients evaluable for efficacy enrolled in 12 clinical sites across the US, with 109 patients receiving Xiaflex as a series of intralesional injections and 36 receiving placebo (3:1 ratio) in the study. The treatment and placebo arms were also randomized to test for a benefit with the addition of penile modelling versus no modeling (1:1). Modelling refers to massaging of the plaque and is intended to maximize the enzymatic effect of the Xiaflex injection in the plaque.

"Xiaflex has shown a sustained benefit at 36 weeks versus placebo for patients suffering from Peyronie's disease," said Laurence A Levine, investigator and professor, Department of Urology, Rush University Medical Center. "The drug had a statistically significant reduction in penile curvature and demonstrated statistically significant improved quality of life for patients as measured by the PRO domain for Peyronie's disease bother. Getting these efficacy results without the risks of surgical intervention would be an enormous advantage for patients suffering from Peyronie's disease."

The most common adverse events reported in the Peyronie's phase-IIb trial were injection site bruising, edema and pain. These adverse events were consistent with previous trials. There have been no drug related serious adverse events or systemic hypersensitivity events reported in this trial or any of the previous Xiaflex Peyronie's disease clinical studies. Including data from all Xiaflex Peyronie's disease clinical studies, over 1,200 Xiaflex injections have been administered to more than 240 Peyronie's patients.

Auxilium Pharma is a specialty biopharmaceutical company with a focus on developing and marketing to urologists, endocrinologists, orthopaedists and select primary care physicians.