Eli Lilly's experimental weight‑loss drug retatrutide shows major weight loss in trials

Retatrupide (LY3437943) is an investigational triple‑receptor agonist targeting GIP, GLP‑1 and glucagon, developed by Eli Lilly. The drug is not yet FDA‑approved and is only available through clinical trials or research‑grade vendors, which vary in documentation quality.

In the Phase 3 TRIUMPH‑4 trial, participants receiving a 12 mg dose lost an average of 71.2 lb (32.3 kg) over 68 weeks, equating to about 24 % body‑weight reduction. Earlier Phase 2 data showed a 17.5 % loss at 24 weeks versus 1.6 % for placebo, and a 24.2 % loss after 48 weeks. The most common side effects were mild to moderate gastrointestinal symptoms; a transient increase in heart rate was also observed. The FDA has issued a warning against using unapproved versions of GLP‑1‑type drugs, emphasizing safety concerns.

Research suppliers list retatrutide with purity standards (≥98 % HPLC, mass‑spec confirmation), but the compound remains experimental.