To evaluate the safety and efficacy of bremelanotide for the treatment of premenopausal women with hypoactive sexual desire disorder. Two identical phase 3, randomized, double-blind, placebo-controlled, multicenter clinical trials (RECONNECT) evaluated the safety and efficacy of bremelanotide 1.75 mg administered subcutaneously as needed in premenopausal women with hypoactive sexual desire disorder. Patients were randomized 1:1 to 24 weeks of treatment with bremelanotide or placebo. Sample size was estimated based on simulations from key endpoints in patients with hypoactive sexual desire disorder from a prior trial. Coprimary efficacy endpoints were change from baseline to end-of-study in the Female Sexual Function Index-desire domain score and Female Sexual Distress Scale-Desire/Arousal/Orgasm item 13. Study 301 began on January 7, 2015, and concluded on July 26, 2016. Study 302 began on January 28, 2015, and concluded on August 4, 2016. Of the 1,267 women randomized, 1,247 and 1,202 were in the safety and efficacy (modified intent-to-treat) populations, respectively. Most participants were white (85.6%), from U.S. sites (96.6%), and had a mean age of 39 years. From baseline to end-of-study, women taking bremelanotide had statistically significant increases in sexual desire (study 301: 0.30, P<.001; study 302: 0.42, P<.001; integrated studies 0.35, P<.001) and statistically significant reductions in distress related to low sexual desire (study 301: -0.37, P<.001; study 302: -0.29, P=.005; integrated studies -0.33, P<.001) compared with placebo. Patients taking bremelanotide experienced more nausea, flushing, and headache (10% or more in both studies) compared with placebo. Both studies demonstrated that bremelanotide significantly improved sexual desire and related distress in premenopausal women with hypoactive sexual desire disorder. The safety profile was favorable. Most treatment-emergent adverse events were related to tolerability and the majority were mild or moderate in intensity. ClinicalTrials.gov, NCT02333071 (study 301) and NCT02338960 (study 302). Palatin Technologies, Inc., and AMAG Pharmaceuticals, Inc.