Structure Therapeutics' aleniglipron data published in Nature Medicine
Structure Therapeutics has secured publication in Nature Medicine for its Phase 2b ACCESS trial of aleniglipron, an oral small-molecule GLP-1 receptor agonist being developed for obesity and overweight with comorbidity.
The paper appeared simultaneously with an oral presentation by lead author Julio Rosenstock at the American Diabetes Association's 86th Scientific Sessions in June 2026.
The ACCESS study evaluated three maintenance doses of aleniglipron in a randomised, double-blind, placebo-controlled design. All three dose arms — 45 mg, 90 mg, and 120 mg — met the primary endpoint and all key secondary endpoints at week 36 with statistical significance, as the company had previously reported. The newly published data add granularity to the tolerability profile and interim results from an open-label extension (OLE) study, which showed continued weight loss beyond the 36-week double-blind period, with no apparent plateau. After a median follow-up of 20 weeks in the OLE, participants in the 45 mg, 90 mg, and 120 mg arms achieved weight reductions of 13.3%, 16.2%, and 15.3% respectively.
Safety and tolerability
Gastrointestinal adverse events were broadly consistent with the established GLP-1 class profile — nausea and vomiting being the most common — though they were generally mild to moderate and declined in frequency over time. The overall treatment discontinuation rate was 10.4%, which the company describes as low relative to the class. Notably, the publication included individual-participant dosing heat maps overlaid with vomiting events, showing that participants who required dose interruptions could typically re-initiate or up-titrate without a meaningful increase in emesis. Structure says this finding supports the durability of adherence and informed the decision to begin Phase 3 with a lower 2.5 mg starting dose.
Blai Coll, Chief Medical Officer of Structure Therapeutics, said the company is "on track to initiate our Phase 3 program of aleniglipron in the third quarter of 2026 with a starting dose of 2.5 mg," adding that the Phase 3 design reflects both the ACCESS data and a completed End of Phase 2 meeting with the FDA.
Market context
Aleniglipron enters a fiercely contested obesity-drug landscape dominated by injectable GLP-1 therapies from Novo Nordisk and Eli Lilly. The oral segment is now attracting significant investment, with Novo Nordisk's oral semaglutide (Rybelsus) already approved for type 2 diabetes and a higher-dose obesity formulation in late-stage development. Pfizer previously discontinued its oral GLP-1 programme following safety findings, which has narrowed the field of oral small-molecule challengers. Structure's non-peptide approach — designed to address the scalability and cold-chain limitations of injectable biologics — is therefore of considerable interest to investors and payers, particularly in markets where injectable supply has been constrained.
The ADA sessions also featured additional Structure data, including preclinical combination results pairing aleniglipron with ACCG-2671, the company's small-molecule amylin receptor agonist, which showed additive weight loss over either agent alone in obese non-human primates. If that combination signal holds in human studies, it could differentiate Structure's pipeline from single-mechanism competitors. Phase 3 initiation in Q3 2026 will be the next key milestone investors watch closely.