TRIUMPH-1: The Phase 3 Trial That Rivals Surgery

In the phase 3 TRIUMPH-1 trial (2,339 participants, 80 weeks), the 12 mg dose of retatrutide produced a mean weight reduction of 28.3% (−70.3 lb), with 45.3% of participants achieving ≥30% weight loss — a level long associated with bariatric surgery. Notably, 65.3% of 12 mg participants crossed below the BMI<30 threshold, including 37.5% of those starting with class 3 obesity (BMI ≥40).

In a pre-specified extension for participants with BMI ≥35, those continuing on 12 mg to 104 weeks lost an average of 85.0 lb (30.3%). The most common adverse events were GI (nausea 42.4%, diarrhea 32.0%, vomiting 25.3% at 12 mg). This thread reviews the full dose-response and safety profile.