Repros Therapeutics (NASDAQ: RPRX), one of the best performing biotech stocks of 2012, is developing Androxal for the treatment of secondary hypogonadism. The profit potential in this space is huge, given that the current market leader -- AbbVie's Androgel -- raked in a whopping $1.19 billion in 2012.

Shares of Repros took a dramatic fall, however, after a company press release indicated some anomalies in one of Androxal's key clinical trials. Healthcare analyst Max Macaluso breaks down this story in the following video.