This study is a double-blind crossover study in female healthy volunteers to compare the pharmacokinetics and safety of a single dose each of two different formulations of Proellex for oral administration. Each formulation will be designated as either Treatment A or Treatment B. A total of 12 subjects who meet the eligibility criteria will be randomized to receive either Treatment A or Treatment B as their first assigned treatment. After a 7-day washout period subjects will receive the alternative treatment. On the day of each treatment subjects will remain in the clinic overnight and undergo 72-hour pharmacokinetic assessment at the following time points: 0, 0.5, 1, 2, 3, 4, 8, 12, 16, 24, 48 and 72 hours after administration of study drug.