Phase 2, double-blind, randomized, placebo-controlled study of the safety and efficacy of elagolix in women with polycystic ovary syndrome. Evaluate the efficacy and safety of elagolix, a GnRH antagonist, to treat polycystic ovarian syndrome (PCOS). A phase 2, multicenter, double-blind, randomized, placebo-controlled trial. Outpatient and academic medical centers. One hundred fourteen women with PCOS (aged 18-35 years, body mass index 18.5-38 kg/m). Patients were randomized 2:2:2:2:2:3 to elagolix (25 mg twice daily, 50 mg once daily, 75 mg twice daily, 150 mg once daily, and 300 mg twice daily) or placebo. The primary endpoint was menstrual cycle normalization (defined as 2 menstrual cycles 21-35 days in length during the 4-month treatment period). The secondary endpoint was change from