Repros Therapeutics Commences Dosing Third Cohort in Low Dose Proellex Study

Repros Therapeutics Inc. RPRXtoday announced it has commenced dosing the 6 mg cohort in the Company's low dose study of Proellex® following a safety review of data from women that have completed 8 weeks of treatment at a 3 mg dose. No signals of liver toxicity were detected to date in the 3 mg group. Increased levels of drug activity were detected in this second cohort. The Company previously noted that it has observed signals of clinically relevant activity at even the lowest dose, 1 mg.

Proellex is an oral therapy in development for the treatment of uterine fibroids and endometriosis. Large Phase III clinical studies exhibited severe liver toxicity in a small percentage of subjects that were exposed to a 50 mg dose. As a result of these observations, the program was placed on full clinical hold until the phenomenon could be better understood. After an analysis of all the subjects that had been exposed to Proellex, Repros petitioned the FDA to allow the Company to conduct a low dose trial to assess impact on the liver and signals of efficacy. In the summer of 2010 the FDA moved Proellex to partial hold status to allow for the low dose study.