Structure Therapeutics reported new clinical data on September 8, 2026 for two separate obesity-drug candidates: 72-week extension results for its oral GLP-1 pill aleniglipron, and early Phase 1 data for a newly disclosed oral amylin and calcitonin receptor agonist. The update gives the clearest picture yet of how the company's oral small-molecule pipeline is positioned against a fast-moving field of injectable and oral obesity drugs.

Aleniglipron: 72-Week Data

Aleniglipron is an investigational oral small molecule designed to activate the GLP-1 receptor, the same target as injectable drugs like semaglutide but delivered as a once-daily pill rather than a weekly injection. In the extension phase of the ACCESS trial, participants who continued treatment reached up to 16.2% body weight loss at 72 weeks, with the company noting "no evidence of a plateau" in the weight-loss curve at that point. About 87% of participants eligible from the initial 36-week double-blind phase chose to enter the 36-week open-label extension, a retention rate the company highlighted as a sign of tolerability.

Tolerability appears to have improved with a lower starting dose of 2.5 mg, a common strategy for reducing gastrointestinal side effects like nausea that are common across the GLP-1 drug class during dose escalation. Fewer than 5% of participants in the extension discontinued treatment specifically due to adverse events.

Next Steps for Aleniglipron

Structure Therapeutics has moved aleniglipron into Phase 3 testing under the name ACCOMPLISH, a program the company says will enroll more than 4,700 participants. Topline data from that Phase 3 program are not expected until the second half of 2028, meaning aleniglipron remains several years away from a possible FDA submission even with positive results so far.

A New Amylin/Calcitonin Candidate

Alongside the aleniglipron update, Structure Therapeutics disclosed early data for ACCG-2671, which it describes as the first reported oral small molecule designed to act on both amylin and calcitonin receptors at once, a dual-mechanism approach distinct from the GLP-1 pathway entirely. In a Phase 1 single ascending dose study of 31 healthy participants, the compound showed an approximately six-day half-life, a pharmacological property consistent with eventual once-weekly dosing, and produced a 3.3% mean reduction in body weight after a single dose. No serious adverse events were reported in this early, small safety study.

A multiple ascending dose trial is already underway, with topline data expected in the first half of 2027. That trial will be the first real test of whether the single-dose weight-loss signal holds up, and what tolerability looks like, with repeated dosing over time.

Regulatory Status

Neither aleniglipron nor ACCG-2671 is approved by the FDA or any other regulator; both remain investigational compounds still in clinical trials. Aleniglipron's Phase 3 program alone is expected to run for roughly two more years before topline results are available, and ACCG-2671 is still in the earliest stage of human testing.

Why It Matters

The oral GLP-1 category is becoming increasingly competitive following the FDA's 2026 approval of orforglipron (marketed as Foundayo) as the first oral GLP-1 pill without food or water restrictions, and with AstraZeneca's elecoglipron also advancing toward Phase 3. Structure Therapeutics' 72-week data give aleniglipron a longer efficacy track record than some rivals, though the company's newest candidate is a reminder of how early-stage most of this pipeline still is. As always, anyone currently managing obesity or diabetes with an approved medication should discuss any changes to their treatment with their own physician rather than an investigational trial readout.