STEP UP MRI substudy shows semaglutide cuts thigh muscle fat infiltration

The wire

1. 01Prespecified secondary analysis of the phase 3b STEP UP trial found treatment differences of -11.1 L adipose tissue, -1.5 L visceral fat and -0.92 percentage points thigh muscle fat infiltration for pooled semaglutide versus placebo at 72 weeks.
2. 02Sit-to-stand repetitions rose from 13 to 15 in both groups, offering clinicians a counterpoint to concerns that high-dose semaglutide erodes muscle function.
3. 03Only 55 of 1,407 participants had valid baseline MRI, with just six on placebo and six on 2.4 mg, so the imaging comparison is small and imbalanced; authors call for further research.

From the source

Effect of Semaglutide on Thigh Skeletal Muscle Volume, Fat Infiltration and Physical Function in People With Obesity: Secondary Analysis of STEP UP

Diabetes, obesity & metabolism · 2026 Sep 20 · Hjelmesæth J, Bhat S, Garvey WT et al.