Tirzepatide for Weight Reduction in Chinese Adults With Obesity

Importance Obesity has become a global public health concern and China has the largest number of affected people worldwide. Objective To assess the efficacy and safety of treatment with tirzepatide for weight reduction in Chinese adults with obesity or overweight and weight-related comorbidities. Design, Setting, and Participants This randomized, double-blind, placebo-controlled, phase 3 clinical trial conducted at 29 centers in China from September 2021 to December 2022 included Chinese adults (aged ≥18 years) with a body mass index (BMI) greater than or equal to 28 or greater than or equal to 24 and at least 1 weight-related comorbidity, excluding diabetes. Interventions Participants were randomly assigned (1:1:1) to receive once-weekly, subcutaneous 10-mg (n = 70) or 15-mg (n = 71) tirzepatide or placebo (n = 69), plus a lifestyle intervention, for 52 weeks. Main Outcomes and Measures Co–primary end points were the percent change in body weight from baseline and weight reduction of at least 5% at week 52. Efficacy and safety analyses were performed on an intention-to-treat population. Results Of 210 randomized participants (103 [49.0%] female; mean [SD] age, 36.1 [9.1] years; body weight, 91.8 [16.0] kg; BMI, 32.3 [3.8]), 201 (95.7%) completed the trial. The mean change in body weight at week 52 was −13.6% (95% CI, −15.8% to −11.4%) with tirzepatide 10 mg, −17.5% (95% CI, −19.7% to −15.3%) with tirzepatide 15 mg, and −2.3% with placebo (difference between 10 mg and placebo, −11.3% [95% CI, −14.3% to −8.3%; P < .001]; difference between 15 mg and placebo, −15.1% [95% CI, −18.2% to −12.1%; P < .001]). The percentage of participants achieving body weight reductions of 5% or greater was 87.7% with tirzepatide 10 mg, 85.8% with tirzepatide 15 mg, and 29.3% with placebo ( P < .001 for comparisons with placebo). The most frequent treatment-emergent adverse events with tirzepatide were gastrointestinal. Most were mild to moderate in severity, with few events leading to treatment discontinuation (<5%). Conclusions and Relevance In Chinese adults with obesity or overweight, once-weekly treatment with tirzepatide 10 mg or 15 mg resulted in statistically significant and clinically meaningful weight reduction with an acceptable safety profile. Trial Registration ClinicalTrials.gov Identifier: NCT05024032