Dr. Pep

Peptides · GLP-1/glucagon dual receptor agonist

Survodutide: what the studies show

Every line below comes from a study, label or regulator record, checked by two models, with the source linked. Information, not medical advice. For adults 18+.

What it is

  • Survodutide (BI 456906) is an investigational once-weekly injected peptide from Boehringer Ingelheim. It activates two receptors, glucagon and GLP-1. It carries a C18 fatty acid so one injection lasts a week. It is not approved in the US.[1][2]
  • It is a separate molecule from retatrutide and mazdutide, which are other glucagon-receptor drugs. A 2026 network meta-analysis compared all three as distinct agents. Results for one do not transfer to the others.[3]

Bottom line

  • Two phase 3 trials report that weekly survodutide cut body weight by about 12 to 13% at 76 weeks in adults with obesity (without diabetes) and about 8 to 10% in adults with type 2 diabetes. Stomach side effects were very common. It is still investigational, and FDA has acted against firms selling it as a 'research' product.[2][4][5]

What the human studies found

  • SYNCHRONIZE-1, a phase 3 randomised, double-blind trial funded by Boehringer Ingelheim, enrolled 725 adults with obesity and no diabetes (mean BMI 37.9). At week 76, weekly survodutide 3.6 mg or 6.0 mg versus placebo (all with lifestyle counselling) changed body weight by -12.2%, -13.0% and -5.4%. Weight fell by 5% or more in 72.6%, 71.9% and 46.3%. No deaths were reported.[2]
  • SYNCHRONIZE-2, a phase 3 trial in 752 adults with obesity and type 2 diabetes, found week-76 weight changes of -8.2% (3.6 mg), -9.8% (6.0 mg) and -3.9% (placebo). HbA1c fell 0.9 and 0.8 percentage points versus 0.2 with placebo.[4]
  • A 46-week phase 2 trial in 387 adults with BMI 27 or more and no diabetes tested 0.6, 2.4, 3.6 and 4.8 mg weekly. Weight changed by -6.2%, -12.5%, -13.2% and -14.9% versus -2.8% with placebo. Only 60.4% completed the 46 weeks.[6]
  • In a 48-week phase 2 trial in biopsy-confirmed MASH with fibrosis stage F1 to F3 (293 treated), MASH improved without worse fibrosis in 47% (2.4 mg), 62% (4.8 mg) and 43% (6.0 mg) versus 14% on placebo. Fibrosis improved by one stage in 34%, 36% and 34% versus 22%.[7]
  • In SYNCHRONIZE-MASLD, a 48-week phase 3 trial of 216 adults with obesity and at-risk fatty liver disease, 6.0 mg weekly cut liver fat by 30% or more in 84.2% versus 24.3% on placebo (efficacy estimand) and weight by 12.2% versus 1.0%. It ran only 48 weeks and recruited in the United States and Spain.[8]
  • A 2025 meta-analysis of 3 RCTs (1,088 people with diabetes and/or obesity, follow-up 4 to 11 months) found larger weight loss than placebo at 2.4 mg and 3.6 mg weekly, and called the results short-term.[9]

Known risks and side effects

  • Stomach side effects were the main problem. In SYNCHRONIZE-1 they occurred in 80.9% (3.6 mg) and 89.7% (6.0 mg) versus 47.9% on placebo. In SYNCHRONIZE-2 they occurred in 72.8%, 77.7% and 38.6%. They were generally mild to moderate.[2][4]
  • In the MASH phase 2 trial, nausea was 66% versus 23% on placebo, diarrhoea 49% versus 23% and vomiting 41% versus 4%. Serious adverse events were 8% versus 7%.[7]
  • In the phase 2 obesity trial, any adverse event occurred in 91% of survodutide recipients versus 75% on placebo, and 75% versus 42% had stomach events.[6]
  • Survodutide has no US label. Class warnings on approved GLP-1 drugs, such as thyroid C-cell tumours and pancreatitis, come from labels for other molecules and are not established for survodutide.[10]

Legal status

  • Boehringer's phase 3 papers describe survodutide as investigational. The corpus holds no FDA approval or label for it.[2][4]
  • FDA warning letters have named survodutide among products sold as unapproved new drugs: Xcel Research LLC (2024-12-10) and NuScience Peptides LLC (2026-08-24). FDA wrote that 'research use only' labels did not stop the products from being drugs for human use.[11][5]
  • FDA's page on unapproved GLP-1 drugs (updated 2026) warns that unapproved versions do not get FDA review for safety, effectiveness or quality. The page text in the corpus does not name survodutide.[12]

Sources

  1. [1] BI 456906: Discovery and preclinical pharmacology of a novel GCGR/GLP-1R dual agonist with robust anti-obesity efficacy.
  2. [2] Survodutide Once Weekly for the Treatment of Adults with Obesity.
  3. [3] Comparative Efficacy and Safety of Glucagon Receptor Agonists on Metabolic Outcomes: A Network Meta-Analysis of Randomised Controlled Trials.
  4. [4] Survodutide Once Weekly in Adults with Obesity and Type 2 Diabetes.
  5. [5] FDA: Warning Letter, NuScience Peptides LLC (2026-08-24), tesamorelin, ipamorelin, PT-141, retatrutide, survodutide, mazdutide
  6. [6] Glucagon and GLP-1 receptor dual agonist survodutide for obesity: a randomised, double-blind, placebo-controlled, dose-finding phase 2 trial.
  7. [7] A Phase 2 Randomized Trial of Survodutide in MASH and Fibrosis.
  8. [8] Survodutide in adults with obesity and metabolic dysfunction-associated steatotic liver disease: SYNCHRONIZE-MASLD, a randomized, double-blind, placebo-controlled phase 3 trial.
  9. [9] Efficacy and Safety of Twincretin Survodutide, a Dual Glucagon-Like Peptide-1 and Glucagon Receptor Agonist as an Anti-Obesity and Anti-Diabetes Medication: A Systematic Review and Meta-Analysis.
  10. [10] Gastrointestinal adverse effects of GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists: A narrative expert review of approved therapies, oral formulations, and pipeline agents.
  11. [11] FDA: Warning Letter, Xcel Research LLC (2024-12-10), retatrutide, semaglutide, cagrilintide, survodutide, mazdutide, sermorelin
  12. [12] FDA: FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss (updated 2026)