Structure Therapeutics obesity pill posts 16% weight loss with no liver injury

Structure Therapeutics said its experimental GLP-1 obesity pill, aleniglipron, showed no signs of drug-induced liver injury in a Phase 2b trial, with patients continuing to lose weight even at lower doses.

"Participants continued to lose weight after a median follow up of 20 weeks in the open label extension phase of the study after finalizing the 36 weeks in the double-blind treatment period, with no apparent weight loss plateau," Julio Rosenstock, MD, chair of the aleniglipron program steering committee and clinical professor of medicine at UT Southwestern Medical Center, said in a statement.

Patients on aleniglipron lost up to 16.2% of their body weight during the open-label extension, with those coming from the 90 mg dose arm showing the most pronounced reduction. The 45 mg and 120 mg dose groups posted 13.3% and 15.3% weight loss, respectively. Only 10.4% of patients discontinued treatment, and gastrointestinal side effects — nausea, diarrhea, vomiting and constipation — were generally mild to moderate and decreased over time. Serious adverse events occurred in one patient on 45 mg, none on 90 mg, and four on 120 mg.

The data, published in Nature Medicine and presented at the American Diabetes Association's 86th Scientific Sessions, removes a key safety concern for the oral small-molecule GLP-1 receptor agonist as it heads into late-stage development. The company plans to initiate its Phase 3 program in the third quarter of 2026 with a 2.5 mg starting dose, designed to improve tolerability during titration. Aleniglipron competes with Eli Lilly's oral GLP-1 pill Foundayo (orforglipron), approved in April, and Novo Nordisk's oral Wegovy pill, launched in January. The global obesity drug market is projected to reach nearly $95 billion by 2030, according to Goldman Sachs estimates.

The positive safety profile strengthens Structure Therapeutics' position in the race for oral obesity treatments, where tolerability has emerged as a key differentiator. Investors will watch for the Phase 3 initiation in Q3 2026 and additional data from the company's amylin and combination programs also presented at the ADA conference.

This article is for informational purposes only and does not constitute investment advice.