Rhythm Pharmaceuticals (Nasdaq: RYTM) announced that Japan's Ministry of Health, Labour and Welfare has granted marketing authorization to Imcivree (setmelanotide) for the treatment of acquired hypothalamic obesity, according to a company statement.

Imcivree, a melanocortin-4 receptor agonist, is described by Rhythm as the first therapy approved in Japan for this condition. The company estimates between 5,000 and 8,000 people in Japan are living with acquired hypothalamic obesity, a rare disease characterized by accelerated and sustained weight gain caused by injury to the hypothalamus.

Rhythm expects to commercially launch Imcivree in Japan before the end of 2026, pending final pricing determination.

The approval is supported by data from the Phase 3 TRANSCEND trial, which enrolled 142 patients with acquired hypothalamic obesity, including 12 patients from a Japanese cohort. The trial met its primary endpoint, with a placebo-adjusted reduction in body mass index of 18.8%. Results were published in The New England Journal of Medicine.

Imcivree had previously received orphan drug designation from Japan's Ministry of Health, Labour and Welfare in March 2025. The drug is already approved in the United States, the European Union, and the United Kingdom for acquired hypothalamic obesity and certain other rare obesity-related conditions.