Characteristics predictive of response to collagenase clostridium histolyticum for Peyronie's disease: a review of the literature.

To evaluate characteristics predictive of successful treatment outcomes of Peyronie's disease (PD) with collagenase clostridium histolyticum (CCH) METHODS: CCH is the only FDA-approved medication for treating PD. We reviewed the literature that addresses pre-treatment clinical characteristics that may predict favorable response to CCH therapy. Despite significant heterogeneity in reporting treatment success, we identified four well-studied characteristics that may be predictive of favorable response to CCH therapy: baseline penile curvature, baseline IIEF, duration of PD, and presence of calcification. CCH demonstrated a favorable response in those with pre-treatment curvature 30°-60°, longer duration of disease, mild to moderate baseline sexual function, and low calcification within plaques. Of all factors, calcification is emerging as the most significant factor likely because CCH is unable to degrade the calcified plaques. There is difficulty interpreting results because of differences in reporting outcomes. Some studies compared treatment groups to placebo, others reported changes in curvature, while others reported > 20% curvature correction as treatment success. Additionally, not all studies reported outcomes after completion of four cycles of CCH, and recent studies utilized a shortened, high dose, modified protocol. The ideal candidate for CCH therapy remains elusive. Based on the available literature, the man with PD who will have the greatest chance of curvature improvement will have curvature between 30° and 60°, longer duration of disease, an IIEF > 17, no calcification, and set to receive all four cycles. For a greater understanding of CCH treatment success in PD, prospectively collected registry reporting standardized outcomes are needed.