Trial · SURMOUNT-4

Continued vs withdrawn tirzepatide: SURMOUNT-4

Name: SURMOUNT-4 — Continued vs withdrawn tirzepatide: SURMOUNT-4
Published: 2026-01-12

Tirzepatide counterpart to STEP-4. Reinforces that GLP-1/GIP obesity therapy is chronic — discontinuation results in regain.

Outcome

After a 36-week open-label lead-in (mean reduction −20.9%), patients were randomized to continue tirzepatide or switch to placebo. Continued therapy added another −5.5% over 52 weeks; placebo switch produced a regain of +14.0%. Net difference roughly 19.5 percentage points.