AstraZeneca's elecoglipron moves to Phase 3 with 11.8% weight loss at 36 weeks

AstraZeneca said on June 8, 2026 that it is moving elecoglipron, an oral small-molecule GLP-1 receptor agonist, into a large Phase 3 program after full results from two Phase 2b trials were presented at the American Diabetes Association's 2026 Scientific Sessions in New Orleans and published simultaneously in The Lancet ^[1].

In the VISTA trial, 310 adults with obesity or overweight plus at least one weight-related condition, and without type 2 diabetes, were randomly assigned to one of five elecoglipron regimens or placebo ^[1][2]. Participants on the 75 mg regimen that used weekly dose increases lost an average of 10.5% of body weight at 26 weeks, versus 0.6% with placebo — one of two co-primary endpoints ^[1]. Weight loss kept going: by week 36, the average was 11.8% on that regimen versus 0.3% with placebo ^[1]. Up to 88.8% of participants on elecoglipron lost at least 5% of body weight at 26 weeks, compared with 15.6% on placebo ^[1][2]. At 36 weeks, roughly 62% of those on the 75 mg regimens reached at least 10% weight loss and about 39–40% reached at least 15%, versus 4.5% and 2.7% on placebo ^[1].

Lower doses did much less. Average weight change at 36 weeks was 2.7% with 5 mg, 6.5% with 15 mg and 9.2% with 50 mg ^[1]. Participants had a mean starting weight of 106.9 kg (about 236 pounds) and a mean BMI of 38.2; mean age was 48.4 years and 73% were female ^[2]. The trial ran in Australia, Canada, Germany, Japan, Taiwan, the UK and the US, enrolling from October 8, 2024 to February 18, 2025 ^[2].

What the diabetes trial showed

SOLSTICE enrolled 404 adults with type 2 diabetes ^[1]. Those on 75 mg lowered HbA1c by an average of 1.9 percentage points from baseline at 26 weeks, versus 0.2 with placebo, the primary endpoint ^[1]. Ninety percent reached an HbA1c below 7% and 85% reached 6.5% or lower ^[1]. Average weight loss was 7.7% versus 1.7% with placebo ^[1]. The trial also included an open-label oral semaglutide arm for exploratory comparison, but AstraZeneca's release does not give those numbers, so how elecoglipron stacked up head-to-head is not yet clear from this announcement ^[1].

Side effects were mostly digestive. In VISTA, nausea was reported by 55% on 75 mg versus 20% on placebo, constipation 41% versus 6%, diarrhea 35% versus 25% and vomiting 29% versus 5% ^[1]. In SOLSTICE, nausea was 37% versus 3% and vomiting 18% versus 1% ^[1]. AstraZeneca says discontinuations due to side effects were "infrequent" in both trials and no liver safety signals were seen ^[1]. The Lancet paper adds context the press release does not: 288 of 310 VISTA participants (93%) completed the study, but only 231 (75%) completed the assigned treatment ^[2]. Overall adverse event rates ranged from 84% to 98% across elecoglipron doses, compared with 84% on placebo ^[2].

One technical point matters for interpreting the headline numbers: VISTA's results used an "efficacy estimand," which estimates what happens in people who take the drug as directed rather than everyone randomized ^[1]. AstraZeneca says that approach was chosen to confirm dosing for Phase 3 ^[1].

Why it matters for patients

Elecoglipron is a once-daily tablet that, per the published paper, is taken without food or fluid restrictions ^[2]. That is the main practical draw of small-molecule oral GLP-1s: no injections and no strict dosing windows. But elecoglipron is not approved anywhere, is not available by prescription, and Phase 2 results in a few hundred people do not establish long-term safety or how much weight people keep off over years.

The tolerability numbers are also worth reading carefully. More than half of people on the top dose reported nausea, and one in four VISTA participants did not finish the assigned treatment ^[1][2]. AstraZeneca says the Phase 2 data were used to redesign the dose-escalation schedule in Phase 3 to improve tolerability ^[1].

What happens next

AstraZeneca plans EMBOLD Phase 3 trials in people with obesity or overweight, with and without type 2 diabetes, and ELUMINATE Phase 3 trials in type 2 diabetes testing elecoglipron alone and combined with dapagliflozin ^[1]. Additional trials will look at long-term cardiovascular and kidney outcomes ^[1]. Start dates, enrollment targets and any filing timeline were not disclosed.