A Master Protocol to Investigate the Efficacy and Safety of LY3437943 Once Weekly in Participants With Type 2 Diabetes Mellitus Who Have Obesity or Overweight: A Randomized Double-Blind, Placebo-Controlled Trial
Eli Lilly and Company
Phase 3 trial evaluating retatrutide once weekly in adults with type 2 diabetes who have obesity or overweight, including a subset with obstructive sleep apnea. Enrolling 1,000 participants across 89 weeks with completion expected May 2026, measuring weight reduction and sleep apnea improvement versus placebo. Eli Lilly advances retatrutide into dual indication territory, competing directly with Novo Nordisk's semaglutide and their own tirzepatide in the expanding cardiometabolic space. The inclusion of sleep apnea patients follows Zepbound's December 2024 OSA approval, positioning retatrutide for multiple obesity comorbidities.
Strategic Signal
Eli Lilly positions retatrutide as their next-generation triple agonist to compete with established GLP-1s in type 2 diabetes plus obesity. The dual primary endpoints mirror Zepbound's successful OSA strategy, targeting specialty sleep medicine alongside endocrinology. US CMS and commercial payers will likely require retatrutide to demonstrate superiority over tirzepatide for dual coverage, given Lilly's own internal competition. This trial design suggests Lilly expects retatrutide to deliver differentiated weight loss beyond tirzepatide's 22.5% in SURMOUNT-1.