Rhythm Pharmaceuticals (Nasdaq: RYTM) announced that the United Kingdom's Medicines and Healthcare products Regulatory Agency (MHRA) has expanded the marketing authorization for Imcivree (setmelanotide) to include the treatment of obesity and control of hunger in adults and children 4 years of age and older with acquired hypothalamic obesity (HO) due to hypothalamic injury or impairment.

The MHRA also granted Imcivree orphan drug designation for acquired HO.

The authorization is based on results from the Phase 2 trial and the Phase 3 TRANSCEND trial. The 120-patient global trial met its primary endpoint, showing a statistically significant -19.8% placebo-adjusted reduction in body mass index (BMI) at 52 weeks. Patients on setmelanotide (n=81) achieved a -16.5% BMI reduction compared with a +3.3% increase among placebo patients (n=39) at 52 weeks (p<0.0001). Adult patients achieved a -19.2% placebo-adjusted BMI reduction, while pediatric patients achieved a -20.2% placebo-adjusted reduction. Results were published in The New England Journal of Medicine.

The most common treatment-emergent adverse events, affecting more than 20% of participants, were nausea, vomiting, diarrhea, injection site reaction, skin hyperpigmentation, and headache.

Imcivree first received marketing authorization in the UK in 2021 for patients with POMC, PCSK1, or LEPR deficiency, followed by Bardet-Biedl syndrome in 2022, and an expanded authorization in 2024 to include children as young as 2 years old.

Rhythm Pharmaceuticals said it plans to work with the UK's National Health Service to finalize coverage guidance for Imcivree for acquired HO.