Tirzepatide after intensive lifestyle intervention in adults with overweight or obesity: the SURMOUNT-3 phase 3 trial

The effects of tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, on weight reduction after successful intensive lifestyle intervention are unknown. This double-blind, placebo-controlled trial randomized (1:1) adults with body mass index >= 30 or >= 27 kg/m(2) and at least one obesity-related complication (excluding diabetes), who achieved >= 5.0% weight reduction after a 12-week intensive lifestyle intervention, to tirzepatide maximum tolerated dose (10 or 15 mg) or placebo once weekly for 72 weeks (n = 579). The treatment regimen estimand assessed effects regardless of treatment adherence in the intention-to-treat population. The coprimary endpoint of additional mean per cent weight change from randomization to week 72 was met with changes of -18.4% (standard error (s.e.) 0.7) with tirzepatide and 2.5% (s.e. 1.0) with placebo (estimated treatment difference -20.8 percentage points (95% confidence interval (CI) -23.2%, -18.5%; P < 0.001). The coprimary endpoint of the percentage of participants achieving additional weight reduction >= 5% was met with 87.5% (s.e. 2.2) with tirzepatide and 16.5% (s.e. 3.0) with placebo achieving this threshold (odds ratio 34.6%; 95% CI 19.2%, 62.6%; P < 0.001). The most common adverse events with tirzepatide were gastrointestinal, with most being mild to moderate in severity. Tirzepatide provided substantial additional reduction in body weight in participants who had achieved >= 5.0% weight reduction with intensive lifestyle intervention. ClinicalTrials.gov registration: NCT04657016.

Automated summary

This study aimed to investigate the effects of tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, on weight reduction after successful intensive lifestyle intervention. The results showed that tirzepatide significantly reduced body weight compared to placebo, with the most common adverse events being mild to moderate gastrointestinal reactions.