Bremelanotide

In plain language

Bremelanotide (brand name Vyleesi) is an FDA-approved medicine for low sexual desire in women who have not gone through menopause. It is a small, ring-shaped peptide made of 7 amino acids.

It works in the brain, not on blood flow like erectile dysfunction pills. It is injected under the skin as needed, at least 45 minutes before sexual activity. Common side effects are nausea, flushing and headache, and it can briefly raise blood pressure.

For students

Bremelanotide is a cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone (α-MSH), about 1,025 Da. It is closely related to melanotan II, differing mainly at the C-terminus. It is a melanocortin receptor agonist, with activity at MC4R thought to drive its effect on sexual desire through hypothalamic pathways.

It was approved in 2019 for premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD) after two Phase 3 trials (RECONNECT) showed modest improvements in desire and reduced distress compared with placebo.

For researchers and instructors

Pharmacology. Nonselective melanocortin agonist (MC1R, MC3R, MC4R and others). MC1R activity explains hyperpigmentation, particularly of the face, gums and breasts, with repeated use.

Clinical evidence. RECONNECT trials (24 weeks) showed statistically significant but modest effects on desire and distress scores; the number of satisfying sexual events did not differ significantly in the co-primary analysis.

Safety. Transient increases in blood pressure and decreases in heart rate after dosing; contraindicated in uncontrolled hypertension or cardiovascular disease. Nausea is the most common adverse effect. The label limits use to one dose per 24 hours and eight per month.

Status. FDA-approved (Vyleesi) for one indication.