Xiaflex for Peyronie’s Disease Decision by FDA due by December 6, 2013

Xiaflex, one of the most promising treatments for Peyronie’s disease in years is due for FDA decision by December 6th deadline as previously reported by us.

We believe that given the results of the randomized controlled trials on hand and no significant negative comments by the FDA the delay is due to FDA concern with limiting the treatment to the more symptomatic and more severe disease such as curvature >30-40 degrees, pain, deformity, functional limitations.

Given the high prevalence of mild, mostly aesthetically concerning disease, treatment of a large population of patients with minimal functional disability is likely to lead to a significant number of side effects that may be more severe than the condition treated.  This is likely to be the greatest concern on the mind of FDA panel in charge of evaluating Xiaflex.  

In fact, FDA is sufficiently concerned about Collagenase that it implemented a fairly robust REMS (Risk Evaluation and Mitigation Strategy) for Dupuytren’s contracture with a palpable cord.

FDA is Concerned about the Potential for Use of Xiaflex in Men with Less Severe Peyronie’s

The greatest concern is penile rupture 1/250 that occurred during sex within 2-3 weeks of injection.  FDA may require a very clear consent / counseling document to avoid sexual intercourse for 2-3 weeks after injections/remodeling.

Most likely, enrollment will require satisfaction of a preset criteria at least the same used in the trials but we suspect that the FDA may choose to be more stringent initially in terms of patient qualification and selection for FDA approved indication.  The randomized studies enrolled patients with >30 degree curvature and non-calcified plaques.