Firdapse meets Phase III endpoints for Lambert Eaton Syndrome - Catalyst Pharma

Catalyst Pharmaceutical has announced positive top-line results from the pivotal Phase III clinical trial of Firdapse (amifampridine phosphate tablets equivalent to 10 mg amifampridine) for the symptomatic treatment of Lambert Eaton Myasthenic Syndrome (LEMS). Both co-primary endpoints, quantitative myasthenia gravis score (QMG) and subject global impression (SGI), demonstrated that Firdapse was significantly superior to placebo, as did a secondary endpoint for the physician's clinical global impression of improvement (CGI-I). This clinical trial was designed as a double blind, randomized, "withdrawal trial" in which all patients were initially treated with Firdapse during a 91 day run-in period followed by treatment with either Firdapse or placebo during a 2 week randomization period. A total of 38 patients completed the 3 month run-in period and subsequent 2 week randomization period. The primary endpoint of change in QMG at day 14 reached statistical significance with a clinically significant worsening of 2.2 points observed in the placebo group. The primary endpoint of change in SGI at day 14 was highly statistically significant with a clinically significant worsening of 2.6 points observed in the placebo group. The secondary endpoint for the physician's CGI-I reached statistical significance with a clinically significant observation at day 14 of 4.7 points in the placebo group. The secondary endpoint of change in walking speed at day 14 showed a worsening of 9.67 ft/min in the placebo group. Firdapse was generally safe and well tolerated.