Overview
- The 68-week study enrolled 445 adults with obesity and confirmed knee osteoarthritis, assigning weekly 9 mg or 12 mg retatrutid versus placebo plus lifestyle counseling.
- Participants on 12 mg lost an average 28.7% of body weight (about 32 kg), while those on 9 mg lost 26.4% (about 29 kg), compared with roughly 2 kg on placebo.
- Treated participants reported knee pain reductions up to 4.5 points on a 0–10 scale versus 2.4 in the placebo group, and Lilly cited improvements in blood pressure, lipids and inflammatory markers.
- Side effects were frequent: nausea in up to 43%, diarrhea in about one third, constipation in roughly one quarter, along with vomiting, appetite loss and dysesthesias reported by up to one fifth.
- Retatrutid targets GLP-1, GIP and glucagon receptors, and Lilly says further analyses and peer-reviewed publication are planned in 2026 as the drug remains unapproved.