SURMOUNT-MAINTAIN Published in The Lancet (May 14): Tirzepatide MTD 7x More Likely to Maintain Weight Loss; 5 mg Step-Down 4x
The Lancet formalized SURMOUNT-MAINTAIN on May 14, 2026, the same day the trial was presented at ECO 2026 in Istanbul. The Phase 3b 112-week study from Dr. Deborah Horn and colleagues at UTHealth Houston re-randomized patients who had reached maximum tolerated dose tirzepatide to continue MTD (15 mg or 10 mg), step down to 5 mg, or switch to placebo. Patients continuing MTD were 7x more likely to maintain their weight loss than those switching to placebo; the 5 mg step-down arm was 4x more likely than placebo. At week 112, MTD continuers preserved all of their initial weight loss; 5 mg-step-down patients lost only 5.6 kg of their initial gains on average. The 'seven times more likely' framing — picked up by EurekAlert and the daily science press — is the cleanest patient-facing summary of maintenance economics published to date.