Investigational weekly injection that hits glucagon and GLP-1 receptors, studied for obesity and fatty liver disease (MASH).
Also called BI 456906, glucagon/GLP-1 dual agonist (Boehringer Ingelheim / Zealand Pharma)
Survodutide is a once-weekly injectable peptide from Boehringer Ingelheim, licensed from Zealand Pharma. It is built on the glucagon sequence and switches on two receptors: the GLP-1 receptor, which cuts appetite the way semaglutide does, and the glucagon receptor, which pushes the liver to burn more fat. It is not approved anywhere as of October 2026.
The big phase 3 trial, SYNCHRONIZE-1, followed 725 adults with obesity but no diabetes for 76 weeks. Counting everyone as randomized, including people who stopped the drug, weight fell 12.2% on 3.6 mg and 13.0% on 6.0 mg, against 5.4% on placebo. The company's headline figure of up to 16.6% comes from the efficacy estimand, which only counts people who stayed on treatment. In people with type 2 diabetes (SYNCHRONIZE-2) the loss was smaller, 8.2% to 9.8% versus 3.9%.
The liver is where survodutide looks most distinct. In a phase 2 biopsy trial in MASH with fibrosis, 43% to 62% of treated patients had their steatohepatitis improve without fibrosis worsening (47% on 2.4 mg, 62% on 4.8 mg, 43% on 6.0 mg), versus 14% on placebo, and the FDA gave it Breakthrough Therapy designation for MASH in 2024. Stomach side effects are common and drove most dropouts. Phase 3 liver outcome trials (LIVERAGE) are still running.
What it binds to, and what happens inside the body after that, step by step.
Survodutide activates both the GLP-1 receptor and the glucagon receptor. GLP-1 activity slows the stomach and reduces hunger signals in the brain. Glucagon activity acts mainly on the liver, raising fat oxidation and energy expenditure and lowering liver fat. In animal work the weight loss came from both eating less and burning more.
Human results and animal results are kept apart below. A result in rats tells you a mechanism is plausible. It does not tell you what happens in a person.
Several large placebo-controlled human trials, including two phase 3 obesity trials of about 725 and 752 people and a phase 3 liver-fat trial, show real weight loss and liver-fat reduction. What is missing is approval, long-term safety beyond 76 weeks, published cardiovascular safety data (the dedicated trial has completed but not reported), and any head-to-head trial against semaglutide or tirzepatide at obesity doses.
725 adults with obesity, no diabetes, 76 weeks
Weight fell 12.2% (3.6 mg) and 13.0% (6.0 mg) versus 5.4% on placebo; GI side effects in 81% to 90% versus 48%.
Read the study752 adults with type 2 diabetes and BMI 27 or higher, 76 weeks
Weight fell 8.2% and 9.8% versus 3.9% on placebo; HbA1c dropped 0.8 to 0.9 points.
Read the study216 adults with obesity and at-risk MASLD, 48 weeks
84.2% on 6.0 mg cut liver fat by at least 30% versus 24.3% on placebo (efficacy estimand); weight fell 12.2% versus 1.0%.
Read the study293 adults with biopsy-confirmed MASH and F1 to F3 fibrosis, 48 weeks
MASH improved without fibrosis worsening in 47% (2.4 mg), 62% (4.8 mg) and 43% (6.0 mg) versus 14% on placebo.
Read the study386 adults with BMI 27 or higher, no diabetes, 46 weeks
Weight fell 6.2% to 14.9% across 0.6 to 4.8 mg versus 2.8% on placebo; only 60% completed the 46 weeks.
Read the study413 adults with type 2 diabetes on metformin, 16 weeks
HbA1c fell up to 1.7 points; weight fell up to 8.7% versus 5.3% with semaglutide 1 mg.
Read the study24 healthy men and 125 adults with BMI 27 to 40
Placebo-corrected weight loss of 13.8% at week 16; 7.5% stopped for cardiac or vascular adverse events during fast escalation.
Read the studyMice in diet-induced obesity models; dogs used only for pharmacokinetics
Lost more weight than mice on maximally effective semaglutide doses, through lower intake plus higher energy expenditure.
Read the studyThese are questions the published research has not answered.
No product containing Survodutide is approved as a medicine by the FDA.
Phase 3 in obesity (SYNCHRONIZE-1, -2, cardiovascular safety, Japan and China trials) and in MASH (LIVERAGE, LIVERAGE-Cirrhosis). FDA Fast Track (2021) and Breakthrough Therapy designation (announced October 2024) for MASH. As of October 2026 no FDA or EMA filing had been publicly announced that we could confirm. WADA: not named on the 2026 list, but it falls under S0 (non-approved substances), which bans any drug with no current regulatory approval for human use, at all times.
No human half-life has been published for Survodutide, so we do not draw a clearance curve. Half-lives quoted online for it are usually estimates from animal data.
This table records the doses that trials and approved labels used, with the source for each row. It is a record of research, not a recommendation, and it is open to free members.
Which symptoms are expected and which mean stop and get help: side effects and red flags.
Tap a claim to see what the studies found.
16.6% is the company's efficacy-estimand figure, which estimates the effect if everyone had stayed on the drug, against 3.2% on placebo. Counting everyone randomized, SYNCHRONIZE-1 showed 12.2% to 13.0% versus 5.4% on placebo, so the drug-attributable loss is about 7 to 8 points.
No head-to-head obesity trial exists. Comparing across trials with different populations and estimands is not a valid comparison.
In a small MRI sub-study of SYNCHRONIZE-1 (about 25 people per arm), lean tissue made up no more than about 11% of the tissue lost. Placebo was not far off, and there is no direct comparison against semaglutide or tirzepatide.
Liver-fat and MASH biopsy results are strong in phase 2 and phase 3 liver-fat trials, but the phase 3 biopsy trial has not read out and there are no head-to-head liver trials.
Only Boehringer Ingelheim makes the clinical product. Online vials have no verified identity, purity, sterility or dose.
No public label. Trial supplies are handled under sponsor instructions that have not been published.
No public label or stability data.
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