Rhythm Pharmaceuticals Launches IMCIVREE in Japan for Acquired Hypothalamic Obesity

BOSTON, Oct. 13, 2026 /CourierPR/ -- Rhythm Pharmaceuticals, a global commercial-stage biopharmaceutical company, has announced the commercial launch of IMCIVREE® (setmelanotide) in Japan for the treatment of acquired hypothalamic obesity (HO). This marks the first approved therapy for patients living with this condition in Japan, where there were no such treatments available until now.

The launch follows the approval by Japan's Ministry of Health, Labour and Welfare (MHLW) of IMCIVREE for acquired HO in August. The approval was based on data from the pivotal Phase 3 TRANSCEND trial, which enrolled 142 patients with acquired HO, including 12 patients from a Japanese cohort and 10 supplemental patients enrolled in addition to the primary 120-patient pivotal cohort. The global study met its primary endpoint, demonstrating a statistically significant 18.8% placebo-adjusted reduction in body mass index (BMI).

Rhythm Pharmaceuticals estimates that approximately 5,000 to 8,000 people are living with acquired HO in Japan. The company has been building its team in Japan to prepare for this launch and is excited about the opportunity to positively impact the lives of Japanese patients. This is a significant milestone in Rhythm's global efforts to bring innovative therapies to patients with rare neuroendocrine diseases.

IMCIVREE is an MC4R agonist designed to treat hyperphagia and severe obesity. In the United States, it is approved to reduce excess body weight and maintain weight reduction long term in adult and pediatric patients aged 4 years and older with acquired HO. In the European Union and the United Kingdom, it is indicated for the treatment of obesity and the control of hunger associated with genetically confirmed Bardet-Biedl syndrome (BBS) or genetically confirmed pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency.

The company is also advancing a broad clinical development program for setmelanotide in other rare diseases, as well as investigational MC4R agonists bivamelagon and RM-718, and a preclinical suite of small molecules for the treatment of congenital hyperinsulinism.

According to the press release, the most common adverse reactions (incidence ≥20% in at least 1 indication) included skin hyperpigmentation, injection site reactions, nausea, headache, diarrhea, abdominal pain, vomiting, depression, and spontaneous penile erection. The company notes that setmelanotide is not indicated for the treatment of patients with obesity due to suspected POMC, PCSK1, or LEPR deficiency with variants classified as benign or likely benign.

This launch is a testament to Rhythm's commitment to transforming the lives of patients living with rare neuroendocrine diseases. The company's forward-looking statements, as detailed in its Quarterly Report on Form 10-Q for the three months ended June 30, 2026, underscore its ongoing efforts to bring innovative therapies to patients in need.