Phosphodiesterase type-5 inhibitor improves both erectile dysfunction, benign prostatic hyperplasia symptoms

Vienna, Austria-The phosphodiesterase type-5 inhibitor tadalafil (Cialis) significantly improves erectile function as well as symptoms of BPH/lower urinary tract symptoms in men with both ED and BPH, according to results of a recent randomized study.

The phase III study, one of several conducted by Eli Lilly on the use of tadalafil in men with BPH/LUTS, tested two different doses of the drug, 2.5 and 5 mg once daily, in men with both ED and BPH/LUTS for 12 weeks. ED severity was assessed with the International Index of Erectile Function questionnaire and at least four sexual attempts of intercourse in the run-in period. Entry criteria were total International Prostate Symptom Score (IPSS) ≥13 and peak urinary flow rate (Qmax) ≥4 to ≤15 mL/s.

Co-primary endpoints were changes in total IPSS and IIEF erectile function domain compared with placebo. Secondary measures included a change in the percentage of positive responses to Sexual Encounter Profile Question 3 (SEP Q3) and BPH Impact Index (BII).

Approximately 600 patients (mean age, 62.6 years) were randomized into three evenly divided groups to receive either tadalafil, 2.5 mg; tadalafil, 5 mg; or placebo. Twenty percent of patients had previously been on an alpha-blocker, and 30% had taken a PDE-5 inhibitor previously. The mean IPSS was 18 points, and the mean IIEF score was 16 points.

Statistically, clinically effective

"The study found that in the co-primary endpoints, the 5-mg daily dose was statistically and, I would suggest, also clinically effective," said Dr. Roehrborn, who presented the results at the European Association of Urology annual congress in Vienna, Austria.

The IPSS improvement was –6.1 points from baseline, 2.3 points over placebo. Improvement in IIEF score was 6.5 points, 4.7 points over placebo.

The percentage of patients who answered positively to SEP Q3 was 32%, an increase from baseline and a 12% increase from the placebo group. For BII, only the 5-mg dose of tadalafil was associated with a significant improvement versus placebo.

The most common adverse effects with tadalafil (those observed in at least 2% of patients) were headache, back pain, and nasopharyngitis. The majority of adverse effects were mild to moderate in severity and the discontinuation rate was low. There was no evidence of urinary retention or of an adverse impact of tadalafil therapy on orthostatic vital signs.

Dr. Roehrborn serves as a consultant/adviser and investigator for Eli Lilly.