Setmelanotide is a prescription drug, not a gray-market research peptide. It is sold under the brand name Imcivree by Rhythm Pharmaceuticals, and the FDA first approved it on November 25, 2020. You will also see it in older literature under its development codes RM-493 and BIM-22493.
Chemically it is a synthetic cyclic octapeptide, closed with a disulfide bridge, with the molecular formula C49H68N18O9S2 (PubChem CID 11993702). It is given as a once-daily subcutaneous injection.
What it does
Setmelanotide is an agonist of the melanocortin-4 receptor (MC4R), a receptor in the hypothalamus that sits at the end of the brain's main appetite-regulating circuit. In several rare genetic conditions, the signal that normally flows through this pathway is broken upstream, so the brain never gets a proper "full" message. The drug is designed to bind MC4R directly and restore signaling through that step, which in trials lowered hunger and body weight (StatPearls, NCBI Bookshelf).
That targeting matters. Setmelanotide was developed for people whose obesity traces to a specific defect in the melanocortin pathway, not for obesity in general.
Who it is approved for
The approvals have expanded over time. As things stand, Imcivree is indicated for:
- Genetically confirmed POMC deficiency (including PCSK1 deficiency) or leptin receptor (LEPR) deficiency
- Bardet-Biedl syndrome (BBS), a ciliopathy that includes obesity, approved in 2022
- Acquired hypothalamic obesity, the most recent expansion
What the trials showed
The pivotal evidence for the original indications came from two single-arm, open-label phase 3 trials led by Karine Clément and colleagues, published in The Lancet Diabetes & Endocrinology in 2020. At roughly one year, 80% of participants in the POMC trial and 45% in the LEPR trial reached at least 10% weight loss, alongside reductions in self-reported hunger (Clément et al., 2020, PubMed).
For Bardet-Biedl syndrome, a separate randomized, double-blind, placebo-controlled phase 3 trial (also published in The Lancet Diabetes & Endocrinology, 2022) met its primary endpoint with significant weight and hunger reductions; results in the smaller Alström syndrome group were inconclusive (Haqq et al., 2022, PubMed).
Safety notes
The most common adverse events across trials were skin hyperpigmentation and injection-site reactions, with nausea and headache also frequent. Per the prescribing information summarized in StatPearls, the drug carries warnings around sexual dysfunction and depression with suicidal-ideation risk, is contraindicated in neonates because of benzyl alcohol content, and is not recommended in pregnancy.
None of this is medical or dosing advice. Setmelanotide is a genuine, regulator-approved medicine prescribed for narrow, genetically or clinically defined conditions, and decisions about it belong with a clinician.
For buyers and quality checks
Because an FDA-approved branded product exists, the meaningful supply is the licensed pharmaceutical, dispensed by prescription. Material sold as "setmelanotide" through research-chemical channels sits entirely outside that approval and quality system, with no guarantee of identity, purity, or sterility. If you are evaluating any peptide claiming to be this compound, the same basic checks apply: a recent certificate of analysis tied to the specific lot, third-party mass-spec identity and HPLC purity testing, and attention to the independent vendor raters this site aggregates. An approved drug name on a vial is not evidence of what is inside it.