Phase 3 SYNCHRONIZE-2 Trial of Survodutide Published in NEJM, Shows Weight and Blood Sugar Improvements in Type 2 Diabetes

The New England Journal of Medicine published the Phase 3 SYNCHRONIZE-2 trial of survodutide online on October 1, 2026, the first full peer-reviewed report of the trial's results. Survodutide (BI 456906) is an investigational once-weekly peptide that activates both the GLP-1 and glucagon receptors, developed by Boehringer Ingelheim under license from Zealand Pharma. The results were presented the same day at the 62nd Annual Meeting of the European Association for the Study of Diabetes in Milan.

SYNCHRONIZE-2 (ClinicalTrials.gov identifier NCT06066528) is a multinational, randomized, double-blind, placebo-controlled Phase 3 trial that enrolled 752 adults with type 2 diabetes and a body-mass index of 27 or higher. Participants were assigned in a 1:1:1 ratio to once-weekly subcutaneous survodutide at 3.6 mg (250 participants), 6.0 mg (251 participants) or placebo (251 participants). The group's mean age was 55.7 years, mean BMI was 36.5, and 49.3% were men. The trial's two primary endpoints, assessed at week 76 under a treatment-regimen estimand that counts the effect of treatment regardless of discontinuation or use of other antiobesity therapies, were percent change in body weight and the proportion of participants achieving at least 5% weight loss.

Average body weight fell 8.2% in the 3.6 mg group and 9.8% in the 6.0 mg group, compared with 3.9% in the placebo group (p<0.001 for both comparisons). At least 5% weight loss was achieved by 57.6% of the 3.6 mg group and 64.5% of the 6.0 mg group, versus 35.1% on placebo. In a separate announcement timed to the publication, Boehringer Ingelheim and Zealand Pharma reported additional results using an on-treatment "efficacy estimand," which excludes the effect of treatment discontinuation: by that measure, weight loss reached up to 13.1% on the 6.0 mg dose versus 3.1% on placebo, and waist circumference fell 11.1 cm versus 3.5 cm.

Blood sugar control also improved. From a baseline glycated hemoglobin (HbA1c) level of 7.4%, the mean change was a reduction of 0.9 percentage points in the 3.6 mg group and 0.8 percentage points in the 6.0 mg group, compared with a 0.2-point reduction on placebo. The most common adverse events were gastrointestinal, generally mild to moderate and transient, occurring in 72.8% of the 3.6 mg group and 77.7% of the 6.0 mg group, versus 38.6% on placebo. Boehringer Ingelheim's announcement additionally reported that 18% of participants on survodutide discontinued treatment because of gastrointestinal adverse events, compared with 1.2% on placebo.

"Obesity and type 2 diabetes are deeply intertwined. For people living with these conditions, sustained weight loss is often a biological struggle rather than a lack of willpower," said Sean Wharton, M.D., PharmD, of McMaster University and the University of Toronto, the trial's coordinating investigator and the paper's first author, in the companies' October 1, 2026 announcement.

Survodutide remains investigational and has not been approved by the FDA, the European Medicines Agency, Australia's Therapeutic Goods Administration or any other regulator. Boehringer Ingelheim is also running a Phase 3 program evaluating survodutide in metabolic dysfunction-associated steatohepatitis. This report describes clinical trial results and is not treatment or dosing guidance.