FDA Extends Review Period for Rhythm Pharmaceuticals’ Imcivree (Setmelanotide) in Acquired Hypothalamic Obesity
The FDA notified Rhythm Pharmaceuticals on November 6, 2025, that the review period for the supplemental New Drug Application (sNDA) for Imcivree (setmelanotide) in acquired hypothalamic obesity has been extended by three months, moving the PDUFA goal date from December 20, 2025, to March 20, 202616.
The extension was prompted by an FDA request for additional sensitivity analyses of efficacy data from Rhythm’s Phase 3 pivotal trial in acquired hypothalamic obesity. No new safety or manufacturing data were requested, and the FDA considers this a 'major amendment'1.
Imcivree, a melanocortin-4 receptor (MC4R) agonist, has already shown substantial benefits in Phase 3 trials, with treated patients achieving up to a 16.5% mean BMI reduction after 52 weeks, compared with a BMI increase in the placebo group57.
Acquired hypothalamic obesity is a rare, severe condition resulting from hypothalamic injury due to surgery, trauma, radiation, or infection, and currently has no approved treatments in the U.S.25.
Imcivree is currently FDA-approved to treat syndromic and monogenic obesity caused by Bardet-Biedl syndrome, POMC, PCSK1, or LEPR deficiency. Expansion to acquired hypothalamic obesity would be a first in this disease segment135.
Rhythm Pharmaceuticals reported no new safety signals in their data for acquired hypothalamic obesity, with side effects consistent with its established profile, including mood changes and sleep disturbances4.
A conference call was scheduled for November 7, 2025, to update stakeholders on the FDA review extension and the company's preparation to deliver setmelanotide for acquired hypothalamic obesity if approved1.
Sources:
1. https://www.globenewswire.com/news-release/2025/11/07/3183568/0/en/Rhythm-Pharmaceuticals-Announces-FDA-Extension-of-Review-Period-for-IMCIVREE-setmelanotide-for-Patients-with-Acquired-Hypothalamic-Obesity.html
2. https://www.managedhealthcareexecutive.com/view/fda-set-review-date-for-imcivree-for-rare-form-of-obesity
4. https://www.biospace.com/drug-development/rhythm-drug-leads-to-reduced-bmi-in-rare-obesity-indication
5. https://www.fiercepharma.com/pharma/rhythms-imcivree-prompts-weight-loss-patients-brain-damage-related-obesity-opening-door
6. https://www.stocktitan.net/news/RYTM/rhythm-pharmaceuticals-announces-fda-extension-of-review-period-for-shrvurxjhlsn.html
7. https://www.clinicaltrialsarena.com/news/rhythm-seeks-market-expansion-imcivree-phase-iii-victory/