Rhythm Pharmaceuticals Announces Additional Positive Data from Phase 3 TRANSCEND Trial of Setmelanotide in Acquired Hypothalamic Obesity

Key Highlights for Investors

• Significant Phase 3 Results: Rhythm Pharmaceuticals (Nasdaq: RYTM) has released new, positive data from its global Phase 3 TRANSCEND trial of setmelanotide in patients with acquired hypothalamic obesity (HO), including supplemental data from 12 Japanese patients and 10 additional patients on top of the primary 120-patient pivotal cohort. The total patient number for the analysis is 142.
• Robust BMI Reduction: The study demonstrated an 18.8% placebo-adjusted difference in BMI reduction for all patients at 52 weeks. The primary endpoint showed a mean BMI reduction of 16.4% from baseline for patients on setmelanotide (n=94), compared to a +2.4% BMI increase for placebo (n=48). The results were statistically significant (p<0.0001).
• Hunger Reduction: Among patients aged 12 and older (n=98), those treated with setmelanotide showed an average weekly reduction of 2.5 points in the most hunger score, versus 1.3 points in the placebo group (p=0.0015).
• Regulatory Milestones: Rhythm’s supplemental New Drug Application (sNDA) for setmelanotide in acquired HO is under review by the FDA, with a PDUFA goal date of March 20, 2026. Additionally, Rhythm will submit the final data package to the FDA on March 2, 2026, ahead of the previously agreed submission date.
• Global Expansion: The European Medicines Agency (EMA) is reviewing a Type II variation submission for setmelanotide for the same indication. Rhythm expects a CHMP opinion in Q2 2026 and potential EU marketing authorization in H2 2026. Rhythm will also submit data to Japan’s PMDA and seek marketing authorization in Japan.
• Market Opportunity: Rhythm estimates 10,000 patients living with acquired HO in the US, another 10,000 in Europe, and 5,000–8,000 in Japan, highlighting significant addressable market potential.

Details on Acquired Hypothalamic Obesity and Setmelanotide

Acquired hypothalamic obesity is a rare disease characterized by rapid and sustained weight gain due to injury to the hypothalamus, often following treatment for craniopharyngioma, astrocytoma, or other hypothalamic-pituitary tumors. Additional causes include traumatic brain injury, stroke, or inflammation. The injury impairs the MC4R pathway, responsible for regulating energy balance and body weight, leading to hyperphagia and reduced energy expenditure. The disease can develop within six months of hypothalamic injury.

Setmelanotide, marketed as IMCIVREE^®, is an MC4R agonist designed to treat hyperphagia and severe obesity. It is currently approved by the FDA, EC, and UK MHRA to reduce and maintain weight reduction in patients aged 2 years and older with syndromic or monogenic obesity due to Bardet-Biedl syndrome (BBS), or genetically confirmed POMC, PCSK1, or LEPR deficiency. Rhythm is also advancing clinical development for setmelanotide in other rare diseases, and investigational MC4R agonists bivamelagon and RM-718.

Safety Profile and Prescribing Information

Setmelanotide is not indicated for obesity due to benign or likely benign POMC, PCSK1, or LEPR variants, or general (polygenic) obesity. Key safety warnings include:

• Sexual Arousal Disturbances: Spontaneous penile erections in males and sexual adverse reactions in females have been reported. Patients should be advised about these risks.
• Depression and Suicidal Ideation: Monitor for new or worsening depression or suicidal thoughts. Discontinue IMCIVREE if clinically significant symptoms occur.
• Hypersensitivity Reactions: Serious hypersensitivity reactions, including anaphylaxis, have been reported. Prompt medical attention and discontinuation are advised if suspected.
• Skin Hyperpigmentation: Increased skin pigmentation, darkening of nevi, and new melanocytic nevi have occurred. Full body skin exams are recommended pre-treatment and periodically.
• Risk in Neonates: IMCIVREE is not approved for neonates or infants due to risk of serious and fatal reactions from benzyl alcohol preservative.
• Adverse Reactions: Most common (≥20%) include skin hyperpigmentation, injection site reactions, nausea, headache, diarrhea, abdominal pain, vomiting, depression, and spontaneous penile erection.
• Use in Specific Populations: Not recommended during breastfeeding; discontinue upon recognition of pregnancy unless benefits outweigh risks.

Potential Price-Sensitive Information

• Positive Phase 3 Data: The substantial BMI reduction and hunger score improvement demonstrated by setmelanotide may position it as the first FDA-approved therapy for acquired hypothalamic obesity, a rare disease with significant unmet need and no approved therapies, representing a potentially lucrative commercial opportunity.
• Regulatory Timeline: The PDUFA goal date of March 20, 2026, for the sNDA review, and anticipated EU and Japan submissions, create major upcoming catalysts for Rhythm’s share price. Investors should monitor these milestones closely.
• Market Expansion: The addressable market estimates in the US, EU, and Japan signal a meaningful revenue growth opportunity if approvals are secured, potentially driving share value.
• Safety and Adverse Events: Attention to adverse events and contraindications is essential, as any unexpected safety issues could impact regulatory outcomes and market adoption.

Forward-Looking Statements

Rhythm Pharmaceuticals cautions that statements regarding regulatory submissions, approvals, product potential, and market estimates are forward-looking and subject to risks and uncertainties. These include regulatory review outcomes, commercial uptake, safety events, and other factors as discussed in Rhythm’s SEC filings.

Corporate Contacts

Investor Relations: David Connolly, Head of Investor Relations & Corporate Communications, Rhythm Pharmaceuticals, Inc., 857-264-4280, [email protected]
Media Contact: Layne Cosgrove, Real Chemistry, (410) 916-1035, [email protected]

Disclaimer: This article is for informational purposes only and does not constitute investment advice or a recommendation regarding Rhythm Pharmaceuticals, Inc. Investors should consult their financial advisors and review company filings with the SEC for further details and risk factors.

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