Who was studied?
The type 2 diabetes trial included a DXA substudy. Of 189 enrolled participants, 103 completed treatment and had both baseline and week-36 scans.
- Participants
- 189 enrolled in substudy
- Duration
- 36 weeks
- Funding
- Eli Lilly
What did the study find?
Mean total fat-mass reduction was 26.1% in the pooled 8 mg groups and 23.2% at 12 mg, versus 4.5% with placebo. Lean-mass loss as a proportion of weight loss resembled other obesity treatments.
What should you keep in mind?
Substantial missing follow-up scans limit interpretation. Fat-mass reduction is a different endpoint from overall weight reduction; the study does not show zero lean-mass loss.
Why it matters
Body weight alone cannot describe what was lost. This substudy adds useful context, without proving that retatrutide preserves all muscle.
Effects of retatrutide on body composition in people with type 2 diabetes: a substudy of a phase 2 trial
Published 2025 · PMID 40609566 · DOI 10.1016/S2213-8587(25)00092-0
Summary by Peptide Lit, checked against the original abstract on October 7, 2026. Read the complete paper for detailed methods and safety results. This page explains published research; it does not recommend a treatment or dose.