Efficacy and safety of once weekly semaglutide 2·4 mg for weight management in a predominantly east Asian population with overweight or obesity (STEP 7): a double-blind, multicentre, randomised controlled trial.

backgroundData on the benefits of the once weekly GLP-1 receptor agonist semaglutide 2·4 mg for weight management in people from east Asia are insufficient. The objective of this study was to determine the efficacy and safety of once weekly semaglutide 2·4 mg versus placebo for weight management in a predominantly east Asian adult population.

methodsThis randomised phase 3a, double-blind multicentre controlled trial (STEP 7) recruited participants from 23 hospitals and trial centres in China, Hong Kong, Brazil, and South Korea. Adults with overweight or obesity, with or without type 2 diabetes, were randomly assigned (2:1) to receive a subcutaneous injection of either semaglutide 2·4 mg or placebo once a week for 44 weeks, plus a diet and physical activity intervention. Randomisation was done in blocks of six with an interactive web response system and was stratified by diagnosis of type 2 diabetes. Participants, investigators, and the trial sponsor were masked to treatment allocation until after database lock. Primary endpoints were percentage change in mean bodyweight and proportion of participants having reached a weight reduction of at least 5% of bodyweight from baseline to week 44. Safety was assessed in all participants who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT04251156, and is now complete.

findingsFrom Dec 8, 2020, to Aug 23, 2022, 448 participants were screened, of whom 375 were randomly assigned to either the semaglutide 2·4 mg group (n=249) or the placebo group (n=126). Estimated mean percentage change in bodyweight from baseline to week 44 was -12·1% (SE 0·5) with semaglutide 2·4 mg versus -3·6% (0·7) with placebo (estimated treatment difference -8·5 percentage points [95% CI -10·2 to -6·8]; p<0·0001). At week 44, the proportion of participants who lost 5% or more of their bodyweight was higher in the semaglutide 2·4 mg group than in the placebo group (203/238 [85%] vs 36/116 [31%]); odds ratio 13·1 (95% CI 7·4-23·1; p<0·0001). Adverse events were reported by 231 (93%) of 249 participants in the semaglutide 2·4 mg group and 108 (86%) of 126 participants in the placebo group, the most common of which were gastrointestinal disorders (168/249, 67% vs 45/126, 36%).

interpretationThe results of this study support the use of semaglutide 2·4 mg for weight management in people of east Asian ethnicity with overweight or obesity and with or without type 2 diabetes.

fundingNovo Nordisk. TRANSLATIONS: For the Mandarin, Portuguese and South Korean translations of the abstract see Supplementary Materials section.