Systematic evidence-based analysis of plaque injection therapy for Peyronie's disease

We evaluated the peer-reviewed urology literature for intraplaque injection of medication for Peyronie's disease and assessed the quality of studies via rigorous evidence-based medicine criteria.

We performed a search of peer-reviewed literature looking at all agents used to treat Peyronie's disease by intraplaque injections. These were then evaluated using the Oxford Centre for Evidence-Based Medicine criteria, which ranks studies from strongest (level 1) to weakest (level 5) strength of evidence.

Of the 19 studies found involving injection therapy for Peyronie's disease, 17 showed positive results. Six studies using injectable corticosteroids were identified and though all showed positive results, they were of level 4 quality. Two collagenase injection studies (one level 4 and one level 2 study) were identified, both of which showed positive results. All four verapamil injection studies found (three level 4 and one level 2 study) showed positive results. Seven papers involving interferon alpha2-beta injections were evaluated (six level 4 and one level 1 study), five of which showed positive outcomes and two of which showed no significant benefit.

Ninety percent of the studies regarding Peyronie's disease showed positive outcomes. Unfortunately, most of these have not offered convincing evidence-based data, with only one positive study meeting level 1 Oxford criteria for clinical efficacy. Standardised outcome measures were not used, making comparisons difficult. These results reveal the need for the development of validated outcome measures and well-designed controlled trials to determine optimal therapeutic intervention for this disorder.