Pfizer's Lyrica positive in two post-marketing studies

Top-line results for global drugs behemoth Pfizer’s already marketed diabetic nerve pain and post-herpetic neuralgia drug Lyrica (pregabalin) capsules demonstrate that Lyrica does not affect the reproductive function in healthy males when compared to placebo. The study was conducted as a post-approval commitment required by the US Food and Drug Administration. Pfizer will continue to further analyze the study results.

The objective of the Assessment of the Impact of Lyrica on Sperm Production in Healthy Volunteers Phase IV, multicenter, double-blind, randomized, placebo-controlled study was to evaluate the effects of Lyrica compared to placebo on sperm concentration in healthy males. A total of 222 subjects were randomized at 12 study centers in the USA. 111 subjects received Lyrica and 109 subjects received placebo for 12 weeks followed by a three-month washout period. Subjects in the Lyrica arm received 600mg/day (300 mg twice daily) for 10 weeks after a two-week titration that started at 100mg/day (50 mg BID). Subjects who could not tolerate 600 mg/day had their dosage reduced to 450 mg/day (225 mg BID) and those who were unable to tolerate 450 mg/day were dropped from the study.1

The primary endpoint of the study, the proportion of subjects with a 50 percent or more reduction in sperm concentration from baseline to end of study (week 26) last observation, was met. The most common adverse events in subjects who received Lyrica compared to those who received placebo were dizziness, somnolence, dissociation and fatigue. The adverse event profile is consistent with that known for Lyrica.