The efficacy and safety of tadalafil: an update

Abstract

OBJECTIVE To provide an update on the efficacy and safety of tadalafil, a phosphodiesterase‐5 inhibitor, in the treatment of erectile dysfunction (ED). PATIENTS AND METHODS In all, 2102 men (mean age 56 years) with mild‐to‐severe ED of various causes were randomized to placebo or tadalafil, taken as needed with no food restrictions, at fixed ‘on‐demand’ doses of 10 or 20 mg in 11 randomized, double‐blind, placebo‐controlled trials lasting 12 weeks. The three co‐primary outcomes were changes from baseline in the erectile function domain of the International Index of Erectile Function (IIEF) and the proportion of ‘yes’ responses to questions 2 and 3 of the Sexual Encounter Profile (SEP). Additional efficacy instruments included a Global Assessment Question (GAQ). RESULTS Compared with placebo, tadalafil gave significantly better outcomes. Patients receiving either dose of tadalafil had a significant mean improvement of 6.5 and 8.6, respectively, in the IIEF erectile function domain score from baseline (P < 0.001 vs placebo). At both doses the mean success rate for intercourse attempts (SEP‐Q3) was 58% and 68%, respectively, compared with 31% in the placebo group (P < 0.001), and 71% and 84% reported improved erections at the endpoint (GAQ), vs 33% on placebo (P < 0.001). Tadalafil was effective up to 36 h after dosing and was effective regardless of disease severity and causes, and in patients of all ages. The most frequent adverse events were headache, dyspepsia, back pain and myalgia. CONCLUSION Tadalafil was an effective and well‐tolerated treatment for ED.

Tadalafil for the treatment of erectile dysfunction

“…Compared with sildenafi l and vardenafi l, tadalafi l is much less inhibitory for PDE6, and it is over 700 times more potent for PDE5 than PDE6 (ICOS 2008). For this reason, tadalafi l has less than 0.1% occurrence of vision abnormalities (Brock et al 2002;Carson et al 2004a).…”

“…A large study of 2102 men from 11 different multicentered, randomized, double-blind, placebo controlled trials of tadalafi l reported the drug is well tolerated overall (Carson et al 2004a). Fifty-one percent of men using tadalafi l 20 mg had at least one adverse event (AE), but only 3.2% discontinued treatment.…”

“…Fifty-one percent of men using tadalafi l 20 mg had at least one adverse event (AE), but only 3.2% discontinued treatment. The most common AEs reported with the 20 mg dose were headache (15%), dyspepsia (8%), and back pain (5%) ( Table 1) (Carson et al 2004a). Most AEs are a result of vasodilation of vascular beds other than in the penis.…”

“…The largest data series exist for the general ED population with mild to moderate ED (Brock et al 2002a;Carson et al 2004a), but tadalafi l has also been shown to be an effective treatment for diffi cult-to-treat ED such as more severe, organic ED evaluated in tertiary care centers (Carson et al 2005a), ED secondary to diabetes mellitus (Saenz de Tejada et al 2002;Fonseca et al 2004), and ED resulting from prostate cancer treatments such as prostatectomy (Montorsi et al 2004;Carson et al 2005b) and radiotherapy (Incrocci et al 2007).…”

“…In an update to Brock and colleagues' study, Carson and associates performed another integrated analysis on all available tadalafi l trials, including the original 1112 men in the 5 trials from Brock and colleagues' original study, plus an additional 1215 men from 6 more recently completed trials (Carson et al 2004a). The same study design, safety measures, and statistical analysis were performed, except patients who received 2.5 mg and 5 mg doses in two of the earlier studies that were included in the analysis by Brock and colleagues were not included by Carson and associates.…”