The FDA guidance provides that the highest allowed dose will be 12mg daily. Repros is currently conducting a Phase II study for the use of Proellex in severe endometriosis and plans to submit a Phase II protocol for the treatment of symptomatic fibroids.
Regarding the proposed uterine fibroid Phase II protocol, the FDA provided guidance as to the appropriate inclusion and exclusion criteria for study subjects as well as the preferred efficacy endpoint. The FDA preferred efficacy endpoint is reduction in excessive menstrual bleeding associated with uterine fibroids.
The FDA also noted the preferred methodology to determine changes in bleeding. Repros will comply with FDA guidance as well as collecting additional efficacy outcomes such as tumor size and other symptomatic relief.
Given the prior experience with Proellex at 6mg and 12mg daily dosages, Repros plans to enroll fewer than 75 women in a three arm, parallel design double blind trial. The study is sized to provide greater than 90% power in demonstrating efficacy associated with reducing subject bleeding.