In a separate "completer" analysis, 83% of men that completed the study and the 24 hour assessment were in the normal range and exhibited a mean 24 hour average testosterone of 425 ng/dL (standard deviation, 135). By comparison the mean 24 hour average for the placebo group was 234 ng/dL (standard deviation, 74.1). The difference between the drug and placebo result was highly statistically significant (p<0.00001).
The co-primary sperm count endpoint prescribed by the FDA was that the drug was to exhibit non-inferiority to placebo at a margin of 20% when assessed from the perspective of the percent of subjects that dropped to ≤ 50% of baseline levels for the Intent-to-Treat population. The primary sperm endpoint was defined as that occurring after 12 weeks of the trial. At that point those men that had valid baseline sperm results exhibited a non-inferior criteria of 20% comparing Androxal to placebo. This finding is consistent with the expected increase in FSH with Androxal that increases or maintains sperm production. J. Richard Trout Ph.D., Professor Emeritus of Rutgers University and a statistical consultant to the pharmaceutical industry, consulted with Repros regarding handling the data consistent with FDA guidance.
Androxal was generally well tolerated. There were no adverse events leading to discontinuation in the Androxal arm. The six men that withdrew early from the Androxal arm of the study were either lost to follow-up or were unable to continue with the study schedule due to relocation or job schedule. There was one early termination in the placebo arm due to an adverse event, nausea.
Joseph S. Podolski, President and CEO of Repros commented, "We are obviously pleased with these results. As we expect full enrollment in the sister pivotal study ZA-302 by the end of May, today's outcome encourages us that a similar outcome will be realized." He further noted, "The apparent increase in awareness of the urology community in the need for a more rational approach to the treatment of secondary hypogonadism compared to current testosterone gel products, as evidenced by the schedule of podium sessions at the upcoming AUA meeting, leads us to believe that Androxal, if approved, will become an important therapy in the treatment of this rapidly growing medical indication."