Study suggests PDE-5 inhibitor improves LUTS in men with BPH

Once-a-day tadalafil (Cialis) at dosages ranging from 5 mg to 20 mg produces measurable benefits in men with BPH and lower urinary tract symptoms, according to a multicenter study presented here yesterday.

The randomized, double-blind, placebo-controlled, parallel-group, dose-escalation study involved 281 men with BPH who were randomized to tadalafil or placebo. The treatment group received tadalafil at 5 mg/day for 6 weeks followed by 6 weeks of the agent at 20 mg/day.

Benefits began to appear at the close of the 6-week phase, with the treatment group showing close to a 3-point improvement (p=.003) in their International Prostate Symptom Score (IPSS) and a significant improvement in their IPSS quality of life score. The IPPS scores improved to a 3.8-point change from baseline at 12 weeks (p=.001). The quality of life scores also showed a significant 1.3-point improvement at 12 weeks.

The BPH Impact Index showed no significant improvement at 6 weeks, but a noticeable improvement at 12 weeks. The subset of sexually active men who nonetheless reported erectile dysfunction showed significant improvements in International Index of Erectile Function (IIEF) scores.

In presenting the data, Claus Roehrborn, MD, of the University of Texas Southwestern Medical Center, Dallas, stressed that the changes seen in both LUTS and ED were true changes, not simply subjective observations of study participants.

"It is of crucial importance to understand that the changes in the symptoms scores were not tied to or related to changes in the International Index of Erectile Function scores; ie, the changes seen were not just a reflection of a general sense of feeling better," he said.

The study produced at least one curious finding. Scores on all parameters showed significant improvement, but there appeared to be no significant improvements in flow rate, an observation that complicates hypotheses as to how the agent works. Tadalafil and other PDE-5 inhibitors, alone and in combination with alpha-blockers, merit further study, Dr. Roehrborn said. The study was funded in part by Lilly ICOS.