Carel le Roux, PhD, MSC, is a director of the Metabolic Medicine Group at the University College of Dublin School of Medicine.

Carel le Roux, PhD, MSC

SYNCHRONIZE-1: Survodutide Achieves Significant Weight Loss Versus Placebo

Survodutide led to significant weight loss among patients with 

, based on the phase 3 SYNCHRONIZE-1 trial.

Announced by parent company Boehringer Ingelheim on April 28, 2026, these data reflect the efficacy of this investigational glucagon/GLP-1 receptor dual agonist. Survodutide has already received Fast Track designation from the 

 in May of 2021 and Breakthrough Therapy designation in September of 2024.

“What makes this drug quite interesting is that it binds both the GLP-1 and the glucagon receptor,” Carel le Roux, PhD, MSC, director of the Metabolic Medicine Group at the University College of Dublin School of Medicine and global coordinating investigator of the study, told 

. “Therefore, we are seeing a lot of benefits that are weight loss dependent, but we also hope to see a lot of benefits that may be weight loss independent – not only those that are associated with GLP-1s, such as the incretin effect, but also what happens when we bind a glucagon receptor, because the liver has a lot of glucagon receptors.”

SYNCHRONIZE-1 was a global, randomized, double-blind, placebo-controlled phase 3 trial running for 76 weeks across 116 clinical sites. Patients with a body mass index (BMI) ≥30 kg/m2 at screening or BMI ≥27 kg/m2 with ≥1 of either 

 were eligible for enrollment. Patients were excluded if they had undergone a body weight change of >5% within 3 months before screening, a glycosylated hemoglobin A1c ≥6.5%, a history of 

 mellitus or T2D mellitus, or heart failure with NYHA functional class IV, among other criteria.

Enrolled patients were randomly assigned in a 1:1:1 ratio to either survodutide 3.6 mg, survodutide 6 mg, or matching placebo, each of which was administered subcutaneously once per week on top of diet and exercise counseling. Patients were assessed onsite or remotely every 2-4 weeks during dose escalation and every 6 weeks thereafter until week 76.

The 2 primary endpoints were percentage change in body weight from baseline at week 76 and the achievement of body weight reduction ≥5% from baseline to week 76. Secondary outcomes included achievement of body weight reduction ≥10%, ≥15%, and ≥20% from baseline, as well as absolute change in systolic blood pressure, waist circumference, body weight, and eating behavior, among others.

According to Boehringer Ingelheim’s announcement, patients in both of the survodutide arms exhibited sustained weight loss of ≤16.6% on average after 76 weeks, which marked a significant decrease compared to the 3.2% in the placebo arm (

 <.0001). Additionally, ≤85% of adults receiving survodutide achieved a body weight reduction of ≥5% by week 76 compared to 38.8% in the placebo arm (

 <.0001). Initial analyses have indicated that these reductions were driven largely by loss of fat tissue rather than lean mass.

“As a clinician, I am always delighted if I have a choice, and when I speak to my patients, they are even more delighted to have that choice,” Le Roux said. “The more crowded the field, the better for my patients and me, because then we can actually start working out what is the right treatment for the right patient at the right time, especially those who have cardio, kidney, liver, and metabolic diseases.”

Full data from the SYNCHRONIZE-1 trial will be presented at the American Diabetes Association (ADA) 2026 Scientific Sessions in June.

Editors’ Note: Le Roux reports no relevant disclosures.

Boehringer Ingelheim. Boehringer Ingelheim’s novel glucagon/GLP-1 dual agonist survodutide achieved significant weight loss of 16.6% delivering meaningful metabolic improvement in people with obesity or overweight in Phase III trial. April 28, 2026. Accessed May 19, 2026. 

https://www.boehringer-ingelheim.com/us/human-health/metabolic-diseases/results-phase-iii-synchronize-1-obesity-trial

Boehringer Ingelheim. A Study to Test Whether Survodutide (BI 456906) Helps People Living With Overweight or Obesity Who do Not Have Diabetes to Lose Weight (SYNCHRONIZE-1). ClinicalTrials.gov Identifier: NCT06066515. Updated March 12, 2026. Accessed May 19, 2026. 

https://clinicaltrials.gov/study/NCT06066515

Videos

Carel le Roux, PhD, MSC, discusses the investigative dual GLP-1/glucagon agonist’s weight loss efficacy in patients with obesity and overweight without T2D.

Carel le Roux, PhD, MSC

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