Retatrutide reduces weight and pain in adults with obesity

Mean body weight fell up to 25.0% with retatrutide versus 3.9% on placebo over 80 weeks in adults with obesity.

The New England Journal of Medicine4 Oct 2026, 07:54 BST

In a phase 3 trial involving 2339 adults with obesity without diabetes, weekly retatrutide injections significantly reduced body weight over 80 weeks. Participants received subcutaneous retatrutide at doses of 4 mg, 9 mg, or 12 mg, or a placebo.

At 80 weeks, the mean change in body weight was -17.6% with 4 mg, -23.7% with 9 mg, and -25.0% with 12 mg, compared with -3.9% in the placebo group. In a subgroup of 574 participants with knee osteoarthritis, retatrutide reduced WOMAC pain scores. In 243 participants with obstructive sleep apnea, the drug also reduced apnea-hypopnea events.

Why it matters

Obesity and related conditions, such as knee osteoarthritis and sleep apnea, contribute substantially to functional impairment. Managing these metabolic and musculoskeletal issues concurrently may help preserve physical mobility and quality of life.

Caveats

The study was conducted only in adults without diabetes over an 80-week duration. The assessments of joint pain and sleep apnea were restricted to smaller predefined subgroups of participants.