LLY’s once-weekly obesity drug retatrutide met all endpoints, showing average 28.3% weight loss at 80 weeks in Phase 3 trials.
Eli Lilly’s retatrutide achieved primary and secondary endpoints in the Phase 3 TRIUMPH-1 trial, demonstrating significant weight reduction and cardiometabolic improvements. Participants on the 12 mg dose lost an average of 70.3 lbs (28.3%) over 80 weeks, with 45.3% losing at least 30% of body weight.
The study included 2,339 adults with obesity or overweight and comorbidities, excluding diabetes. Lower doses of 9 mg and 4 mg resulted in average weight losses of 25.9% and 19.0%, respectively. A 104-week extension for higher BMI participants showed the 12 mg dose reached an average loss of 85.0 lbs (30.3%).
Adverse events were consistent with incretin therapies, including nausea, diarrhea, and constipation. Discontinuation rates due to side effects ranged from 4.1% to 11.3% across doses, compared to 4.9% for placebo.