Retatrutide Phase 3 Trial for Obesity and Overweight Completes Primary Study

The Phase 3 study (NCT05929066) investigating retatrutide for participants with obesity or overweight completed its primary study phase on April 30, 2026. This trial, which enrolled 2300 participants, also included subsets of individuals with knee osteoarthritis or obstructive sleep apnea.

Background

Retatrutide (also known as LY3437943) is being evaluated as a potential treatment for individuals diagnosed with obesity or who are overweight. The master protocol for this study, J1I-MC-GZBJ, also includes specific addenda for participants with knee osteoarthritis (OA) (J1I-MC-GOA1) and obstructive sleep apnea (OSA) (J1I-MC-GSA1).

Trial design

The study, titled "A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight" (NCT05929066), is a Phase 3 trial. It enrolled 2300 participants who have obesity or are overweight. The trial also included subsets of participants with knee osteoarthritis or obstructive sleep apnea. Interventions included administration of retatrutide or placebo. The study duration is approximately 89 weeks, involving up to 24 visits. An optional addendum allows approximately 500 participants to continue treatment with retatrutide for an additional 24 weeks.

What this means

The primary completion of this Phase 3 trial marks a significant milestone in the development of retatrutide for obesity and overweight. While no efficacy or safety results are available at this stage, the completion of the primary study phase indicates that the main data collection period for the trial's core objectives has concluded. Future data analyses will provide insights into the efficacy and safety profile of retatrutide across the studied populations, including those with co-morbidities like knee osteoarthritis and obstructive sleep apnea.

Source

The information regarding the primary completion of this trial was obtained from ClinicalTrials.gov, a public database of clinical studies. The update for study NCT05929066, titled "A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight," was posted with a primary completion date of April 30, 2026 on clinicaltrials.gov.