Rhythm Pharmaceuticals Inc

Rhythm Pharmaceuticals is a commercial-stage biopharmaceutical company focused on rare neuroendocrine diseases, centered on the melanocortin-4 receptor (MC4R) pathway. Its marketed product, IMCIVREE (setmelanotide), is an MC4R agonist that treats hyperphagia and severe obesity.

In the U.S., IMCIVREE is approved for:
- acquired hypothalamic obesity (HO) in patients aged 4 and older (approved March 2026);
- obesity due to Bardet-Biedl syndrome (BBS) in patients aged 2 and older;
- obesity due to POMC/PCSK1 or LEPR deficiency in patients aged 2 and older.

Outside the U.S., it is authorized in the EU and UK for BBS and POMC/PCSK1/LEPR deficiency, and for acquired HO in the EU, UK, Japan (launched October 2026) and Canada. European acquired HO launches are planned from 2027, starting with Germany. Revenue comes from net product sales, with roughly three-quarters generated in the U.S.

The pipeline includes:
- bivamelagon, an oral daily MC4R agonist in-licensed from LG Chem, moving into Phase 3 trials in acquired HO and Prader-Willi syndrome;
- RM-718, a weekly injectable MC4R agonist in a Phase 1/2 PWS trial;
- a setmelanotide substudy in congenital HO;
- preclinical small molecules for congenital hyperinsulinism.

The company finances operations with product revenue, a revenue interest financing agreement with HealthCare Royalty, and a new term loan facility of up to $750 million. Updated Nov 3, 2026