---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-26-019995"
form_type: "8-K"
ticker: "RYTM"
cik: "0001649904"
company_name: "RHYTHM PHARMACEUTICALS, INC."
filed_at: "2026-03-20T23:59:59+00:00"
generated_at: "2026-05-15T09:29:38.403252+00:00"
event_type: "regulatory"
sentiment: "positive"
materiality_score: 0.9
calibrated_materiality_score: 0.9
confidence: "high"
source: SEC EDGAR
---

# Rhythm Pharma wins FDA approval for IMCIVREE in acquired hypothalamic obesity; Phase 3 shows -18.4% BMI reduction

## Summary
- FDA approved IMCIVREE (setmelanotide) for acquired HO in adults and children 4+; first approved therapy for this indication.
- Phase 3 TRANSCEND: setmelanotide (-15.8% BMI) vs placebo (+2.6%) at 52 weeks; placebo-adjusted -18.4% (p<0.0001).
- Most common AEs (>20%): skin hyperpigmentation, nausea, vomiting, headache.
- Rhythm estimates ~10,000 U.S. patients with acquired HO; drug available immediately.
- IMCIVREE already approved for BBS and monogenic obesity due to POMC/PCSK1/LEPR deficiency.

## SEC filing metadata
- accession: 0001628280-26-019995
- form_type: 8-K
- ticker: RYTM
- cik: 0001649904
- company_name: RHYTHM PHARMACEUTICALS, INC.
- filed_at: 2026-03-20T23:59:59+00:00
- event_type: regulatory
- sentiment: positive
- materiality_score: 0.9
- calibrated_materiality_score: 0.9
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1649904/000162828026019995/0001628280-26-019995-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1649904/000162828026019995/rytm-20260319.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-26-019995
- JSON: https://secwatch.observer/filing/0001628280-26-019995.json
- Plain text: https://secwatch.observer/filing/0001628280-26-019995.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.