The sBLA submission is based on data from the clinical studies known by the acronym IMPRESS – The I nvestigation for M aximal P eyronie's R eduction E fficacy and S afety S tudies – and other controlled and uncontrolled clinical studies, in which over 1,000 Peyronie's disease patients were enrolled and received over 7,400 injections of XIAFLEX.
In the two phase III double-blind placebo-controlled IMPRESS studies, XIAFLEX demonstrated statistically significant improvement in the co-primary endpoints of penile curvature deformity and patient-reported bother versus placebo. In IMPRESS I at 52 weeks, the co-primary endpoints met statistical significance with a 37.6% mean reduction in penile curvature deformity for XIAFLEX subjects (p=0.0005) and a 3.3 point improvement in the Peyronie's Disease Questionnaire (PDQ) bother domain for XIAFLEX subjects (p=0.0451). In IMPRESS II at 52 weeks, the co-primary endpoints met statistical significance with a 30.5% mean improvement in penile curvature deformity for XIAFLEX subjects (p=0.0059) and a 2.4 point improvement in the PDQ bother domain for XIAFLEX subjects (p=0.0496). XIAFLEX was generally well-tolerated. The most common treatment related adverse events reported in the phase III studies were local to the treatment site and consistent with adverse events reported in previous PD trials with XIAFLEX, which included injection site hematoma, pain and swelling. Serious adverse events included corporal rupture (penile fracture) in 3 subjects in the placebo controlled studies.
About Peyronie's Disease PD is the development of collagen plaque, or scar tissue, on the shaft of the penis that may harden and reduce flexibility, causing the penis to deform in a bend or arc during erection. In addition to difficulty with sexual intercourse, PD is commonly associated with significant disease bother, emotional distress, loss of self-esteem, and depression. PD is a heterogeneous disease with an initial inflammatory component. This inflammatory phase is poorly understood with a somewhat variable disease course and occasional spontaneous resolutions of not greater than 13% 1. After 12-18 months of disease, the disease is reported to often develop into a more chronic, stable phase 1. The estimated prevalence in adult men of PD has been reported to be approximately 5% 2; however the disease is thought to be underdiagnosed and undertreated 1. Based on U.S. historical medical claims data, it is estimated that between 65,000 and 120,000 PD patients are diagnosed every year, but only 5,000 to 6,500 PD patients are treated with injectables or surgery annually 3.
(1) L.A. Levine Peyronie's Disease: A Guide to Clinical Management. Humana Press: 10-17, 2007. (2) Bella A. Peyronie's Disease J Sex Med 2007;4:1527–1538(3) SDI and data on file, Auxilium