Aleniglipron is Structure Therapeutics' once-daily oral small-molecule GLP-1 receptor agonist, the clearest non-Lilly challenger in the oral incretin race. The drug is not a peptide, but it acts on the same receptor as semaglutide and competes directly with Lilly's orforglipron (Foundayo) in pill form.
The Phase 2b ACCESS program is the data anchor. In ACCESS II, aleniglipron drove up to 16.3% placebo-adjusted weight loss over 44 weeks, among the strongest oral-GLP-1 figures reported, with the kind of GI tolerability profile that has held under titration. The full dataset was published in Nature Medicine on June 5, 2026 (Rosenstock and colleagues), with a same-day oral presentation at the ADA Scientific Sessions in New Orleans. Structure has end-of-Phase-2 FDA alignment and plans to start the Phase 3 obesity program in Q3 2026 with a 2.5 mg starting dose, alongside parallel diabetes and combination work with amylin partners.
Stories here cover the ACCESS readouts, Phase 3 design and execution, and how aleniglipron stacks up against orforglipron and the Chinese oral entrants. See #structure-therapeutics, #oral-glp-1, and #access for adjacent threads.
On September 8, 2026, Structure reported ACCESS Phase 2b open-label extension data at 72 weeks: mean 16.2% body weight loss at the 180 mg dose with no observed plateau (14.4% at 90 mg, 11.6% at 45 mg). Fewer than 5% of participants discontinued for adverse events on the 2.5 mg starting dose plus four-week titration. The Phase 3 ACCOMPLISH program enrolls up to 3,600 obesity patients (ACCOMPLISH-1) and 1,100 obesity plus type 2 diabetes patients (ACCOMPLISH-2); topline is expected H2 2028. Same-day, Structure also disclosed first-in-human data for ACCG-2671, an oral amylin/calcitonin dual agonist with a ~6-day half-life supporting once-weekly dosing.
Structure Therapeutics (NASDAQ: GPCR) reported Tuesday September 8, 2026 positive data across two lead oral small-molecule obesity programs. Aleniglipron (oral small-molecule GLP-1 receptor agonist, formerly GSBR-1290) reached mean 16.2% body weight loss at 72 weeks at the 180 mg dose in the ACCESS Phase 2b open-label extension (11.6% at 45 mg, 14.4% at 90 mg), with no observed weight-loss plateau; fewer than 5% of participants discontinued for adverse events using the improved 2.5 mg starting dose with four-week titration. The Phase 3 ACCOMPLISH program enrolls up to 3,600 adults with obesity plus comorbidity (ACCOMPLISH-1) and up to 1,100 with obesity plus type 2 diabetes (ACCOMPLISH-2), with topline expected H2 2028. Separately, ACCG-2671 (oral small-molecule dual amylin and calcitonin receptor agonist) posted first-in-human Phase 1/2a single-ascending-dose data in 31 healthy volunteers: 3.3% body weight reduction after a single 10 mg dose at Day 24, ~6-day half-life supporting once-weekly dosing, CTX-1 bone resorption biomarker reduction ~60% by Day 2, no serious adverse events, no drug-induced liver injury, no nausea or vomiting at 1-2 mg doses (dose-related GI effects at 5+ mg). A 12-week multiple-ascending-dose trial in obese participants is enrolling with topline expected H1 2027. Despite the data, GPCR shares fell in Tuesday trading on incumbent-class competitive concerns.
Structure Therapeutics (NASDAQ: GPCR) reported detailed Phase 2b ACCESS II trial results for aleniglipron (once-daily oral small-molecule GLP-1 receptor agonist for obesity). Key efficacy: 16.3% placebo-adjusted mean weight loss at the 180 mg dose (39 lbs) and 16.0% weight loss at the 240 mg dose (37 lbs) at 44 weeks. This positions aleniglipron as the highest-efficacy oral GLP-1 agonist data reported to date, above Eli Lilly's orforglipron (Foundayo, 7.5-11.2% at 72 weeks in ATTAIN-1) and Novo Nordisk's Wegovy pill (oral semaglutide 25/50 mg, roughly 15% at 68 weeks in OASIS 4). The core Phase 2b ACCESS study had documented 11.3% placebo-adjusted weight loss at 120 mg at 36 weeks. The ACCESS Open-Label Extension (OLE) study documented continued weight loss from 36 weeks up to 16.2% (40.5 lbs) with 120 mg at 56 weeks with no observed plateau, an important tolerability and durability signal. Tolerability profile is consistent with the GLP-1 receptor agonist class with only 3.7% adverse-event-related treatment discontinuation across all active arms in participants who reached 120 mg or higher from weeks 28 to 44. Phase 3 initiation is expected in H2 2026. Aleniglipron is a non-peptide small molecule that binds the GLP-1 receptor, similar to Lilly's orforglipron but distinct from the peptide-based semaglutide and tirzepatide; the small-molecule format provides manufacturing scalability advantages over peptide APIs.
BioSpace's reaction to AstraZeneca's elecoglipron VISTA Phase 2b readout (10.5% weight loss at 26 weeks) framed it as 'relatively underwhelming' next to Structure Therapeutics' aleniglipron (up to 16.3% at 44 weeks, Nature Medicine publication on Friday). Both are oral small-molecule GLP-1s with Phase 3 plans for the second half of 2026, but elecoglipron's lower number gives Structure a clearer differentiation story heading into its Phase 3 start. AstraZeneca will lean on its combination strategy with dapagliflozin and AZD0780 to position elecoglipron.
Monday's data sharpened the oral GLP-1 competitive map. Lilly's Foundayo (orforglipron) leads with a Phase 3 head-to-head win over oral semaglutide and a Q2 FDA filing pending. Structure's aleniglipron sits closest, with 16.3% Phase 2b weight loss and Nature Medicine publication on Friday. AstraZeneca's elecoglipron just cleared Phase 2b. Chinese entrants Hengrui-Kailera (ribupatide, HRS-7535) added Phase 2 and 3 readouts. Novo's Wegovy pill remains the only currently-approved oral, but the next-wave field is now broad and head-to-head data are arriving fast.
Nature Medicine published Structure's Phase 2b ACCESS trial of aleniglipron, the once-daily oral small-molecule GLP-1, on June 5, with lead author Julio Rosenstock presenting the full data in a 12:45 p.m. CT oral session at ADA 2026 the same afternoon. The 44-week ACCESS II readout reached up to 16.3% placebo-adjusted weight loss, the strongest oral GLP-1 number outside Lilly's, and Structure plans to start Phase 3 in Q3 2026 with a 2.5 mg starting dose after end-of-Phase-2 FDA alignment.
The American Diabetes Association's late-breaking abstracts release Friday, June 5 at 6:30 p.m. Central, opening the meeting's data flood in New Orleans (June 5-8). Queued readouts include MetaVia's dual oxyntomodulin DA-1726 and GPR119 agonist vanoglipel, Structure's oral aleniglipron, and Hengrui and Kailera's oral incretins, alongside the Phase 3 retatrutide symposium June 6 and the orforglipron symposium June 8. Novo Nordisk holds an R&D investor event June 7.
Structure Therapeutics will present five obesity and diabetes studies at ADA 2026, anchored by its once-daily oral small-molecule GLP-1 aleniglipron, which posted up to 16.3% placebo-adjusted weight loss at 44 weeks in the Phase 2 ACCESS II trial, among the highest reported for an oral GLP-1. The company has FDA end-of-Phase-2 alignment and plans to start a Phase 3 obesity trial in Q3 2026, with amylin and combination data also on the slate.