Effect of once-weekly subcutaneous semaglutide on abdominal visceral fat area in Japanese adults with overweight and obesity: A post hoc analysis of the STEP 6 trial

Objective: A post hoc analysis of a subset of participants with visceral fat area (VFA) measurements in the STEP 6 trial was conducted to examine both the correlation between VFA and clinical parameters and the effect of semaglutide on VFA in key subgroups. Methods: Participants were Japanese adults aged ≥ 20 years with obesity disease, randomized to once-weekly subcutaneous semaglutide 2.4 mg, semaglutide 1.7 mg, or placebo, plus lifestyle recommendations, for 68 weeks. Correlation between baseline VFA (and change in VFA from baseline to week 68) and clinical parameters (body weight, body mass index [BMI], waist circumference, hepatic parameters, glycated hemoglobin, blood pressure, lipids, high-sensitivity C-reactive protein, and plasminogen activator inhibitor-1 [PAI-1]) was evaluated. Percentage change in VFA between semaglutide and placebo was compared across subgroups. Results: Among 180 participants (semaglutide 2.4 mg, n = 89; semaglutide 1.7 mg, n = 46; placebo, n = 45), mean VFA was 170.0 cm² across subgroups. A positive correlation (Pearson's correlation coefficient [r] ≥0.3) was observed between baseline VFA and body weight (r = 0.415), BMI (r = 0.374), and both JASSO and WHO criterion waist circumference (r = 0.458 and r = 0.555). Correlation between changes in VFA and body weight, waist circumference, high-density and very low-density lipoprotein cholesterol, triglycerides, PAI-1, aspartate aminotransferase, and alanine transaminase were observed in ≥ 1 treatment arm. Semaglutide 2.4 mg and 1.7 mg reduced VFA compared with placebo in all subgroups. Conclusions: VFA partially correlated with clinical parameters in Japanese adults with obesity disease. Subcutaneous semaglutide was an efficacious treatment option for the reduction of VFA, regardless of clinical characteristics. Trial registry name: CT.gov