§ GLP-1 & Weight Loss
SURMOUNT-1
The pivotal randomized trial of tirzepatide for chronic weight management (NEJM, 2022).
Fact-checked 12 May 2026Plain-English Reference
SURMOUNT-1 was a 72-week double-blind randomized trial of 2,539 adults with obesity (without diabetes). Tirzepatide produced 15.0%, 19.5%, and 20.9% mean weight loss at the 5 mg, 10 mg, and 15 mg doses respectively, versus 3.1% on placebo. SURMOUNT-1 is the basis for Zepbound's FDA approval.