Tadalafil monotherapy in management of chronic prostatitis/chronic pelvic pain syndrome: a randomized double-blind placebo controlled clinical trial

In this placebo-controlled trial, we aimed to evaluate the clinical results of using PDE-5 inhibitor, tadalafil 5 mg OD, for management of CP/CPPS.140 patients ≤ 45 years old with moderate/severe CP/CPPS associated with ED (IIEF-5 < 22) were randomly divided and received either tadalafil 5 mg OD (tadalafil-group) or placebo (control-group) for 6 weeks. Post-treatment CPSI scores were compared to baseline and to placebo. Clinically significant responders (≥ 25% reduction from baseline score) were calculated. Tadalafil-induced changes in IIE-5 were evaluated in correlation to that of CPSI scores.By the 6th week, 59 and 56 patients were available in both groups respectively. Compared to baseline, tadalafil-group patients showed significant improvement in total, pain, urinary and Qol domains of CPSI (19.1 ± 5.26, 10.42 ± 3.55, 4.2 ± 1.72 and 4.47 ± 1.64 vs. 24.21 ± 5.05, 12.14 ± 3.57, 6.08 ± 1.53 and 6.22 ± 1.76), p < 0.5. When compared to placebo, all 6th week CPSI domains scores, except for pain, were significantly better in tadalafil-group (p < 0.05). Post-treatment pain score didn't significantly differ between both groups (10.42 ± 3.55, vs. 11.71 ± 3.9, p > 0.05). Clinically significant responders were 30 patients (50.8%) in tadalafil-group vs. 3 patients (5.4%) in control. Tadalafil-induced changes in IIEF-5 score had weak but significant correlation to Qol domain (r = - 0.28, p < 0.05).Tadalafil 5 mg OD can significantly improve all CPSI domains as compared to baseline. Post-treatment CPSI scores, except for pain, were better than placebo. About 50.8% of patients can develop ≥ 25% reduction in their total CPSI scores after treatment. Apart from Qol domain, these changes are not significantly correlated to tadalafil-induced IIEF-5 scores changes.