Eli Lilly’s retatrutide hits Phase 3 milestone with 17% weight loss in type 2 diabetes trial

Eli Lilly and Company (NYSE:LLY) today announced positive topline results from TRANSCEND-T2D-1, the first Phase 3 clinical trial evaluating retatrutide for the treatment of type 2 diabetes.

Retatrutide is a first-in-class investigational molecule that activates three different nutrient-stimulated hormone receptors: glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon.

The study, which included adults with inadequate glycemic control via diet and exercise alone, demonstrated that retatrutide delivered superior results compared to placebo across all tested doses.

At the 40-week mark, participants receiving the 12 mg dose of retatrutide achieved a mean A1C reduction of up to 2% from a baseline of 8.2%.

Beyond glycemic control, the weight loss results were particularly striking for a diabetes population, who typically find weight reduction more challenging than those with obesity alone.

Patients on the 12 mg dose lost an average of 16.8% of their body weight, equivalent to approximately 36.6 lbs.

Notably, the data showed that weight loss had not yet reached a plateau by the end of the 40-week period, suggesting potential for further reduction with longer-term treatment.

The trial also reported significant improvements in cardiovascular risk markers, including reductions in systolic blood pressure and non-HDL cholesterol.

The safety profile of retatrutide remained consistent with other incretin-based therapies.

The most frequently reported adverse events were gastrointestinal in nature—primarily nausea, diarrhea, and vomiting—and occurred mostly during the initial dose-escalation phase.

These events were generally mild to moderate and rarely led to the discontinuation of the treatment.

With this successful readout, Eli Lilly continues to solidify its leadership in the cardiometabolic space.

Retatrutide is currently being evaluated in a broader Phase 3 program known as TRANSCEND, which includes studies focused on obesity, obstructive sleep apnea, and chronic kidney disease