Coverage Initiated: February 2006

Repros Therapeutics (RPRX) has run into significant regulatory issues with its only two drugs, Androxal and Proellex.

In 2009, the FDA put a clinical hold on the pivotal program for Proellex due to demonstrated liver toxicity. The drug was in trials for endometriosis and uterine fibroids. Women taking upper doses of drugs had cumulative liver toxicity. The company entered 2011 working on various dosing levels in an effort to convince the FDA to lift the currently partial clinical hold. Our research includes commentary on the likely source of the liver toxicity, which had not shown up in prior human or animals studies.

Androxal is intended to stimulate natural testosterone production. This differs from other drugs for the treatment of testosterone deficiency that simply add more testosterone. Androxal should be able to access 50-80% of the multi-billion worldwide market for testosterone therapy. FDA reviewers have essentially put a stop to new testosterone drugs, so Repros is trying to find an approval pathway in restoration of fertility in men who have been on testosterone replacement.

A complete listing of our research on Repros is available by clicking here.