Erectile Dysfunction   

The Problem

According to the Massachusetts Male Aging Study (MMAS), erectile dysfunction (ED) is a condition that affects an estimated 52 percent of men between the ages of 40 and 70. The prevalence of ED increases with age and can be affected by a variety of factors, including medications (anti-hypertensives, histamine receptor antagonists); lifestyle (tobacco, alcohol use); diseases (diabetes, cardiovascular conditions), and spinal cord injuries.

The Product

Avanafil is a selective phosphodiesterase type 5 (PDE5) inhibitor, oral medication under investigation for the treatment of ED.

Status

Phase 3 data from the REVIVE study in 646 patients with a history of generalized ED for at least six years, demonstrated statistically significant improvement in erectile function as measured by the Sexual Encounter Profile (SEP) and improvements in the International Index of Erectile Function (IIEF) score.  The study also demonstrated successful intercourse in as little as 15 minutes or less. The most commonly reported adverse events were headache, flushing, back pain, and nasal congestion. The Phase 3 study was conducted under a Special Protocol Assessment with the U.S. FDA.

REVIVE (TA-301) is the first of four phase 3 avanafil trials. Additional phase 3 studies include treatment in diabetic males with ED (REVIVE-Diabetes, TA-302) and in males with ED following a post-radical prostatectomy (TA-303), each with a treatment period of approximately 16 weeks.  In March of this year, VIVUS initiated an open-label safety study (TA-314) evaluating the long-term safety and tolerability of avanafil as part of its path toward NDA filing.  TA-314 is being conducted over one year in approximately 600 patients across 40 U.S. centers; patients completing either the 12-week REVIVE or REVIVE-Diabetes studies are eligible to participate in TA-314.  Results of the study are expected to be available by late-2010.  In total, the phase 3 avanafil clinical program will enroll approximately 1,300 patients.