Peptide guide

Survodutide: What the Evidence Actually Shows

Also called BI 456906, Glucagon/GLP-1 receptor dual agonist

Survodutide is a glucagon receptor and GLP-1 receptor dual agonist, and it is the compound on this site where you can watch a headline number get smaller as the evidence gets better. Its phase 2 trial reported 14.9% weight reduction at 46 weeks on 4.8 mg. Its phase 3 trial, SYNCHRONIZE-1, used a higher dose, ran 30 weeks longer, and reported 13.0% — against a placebo arm that lost 5.4%, leaving a gap over placebo of about 7.6 percentage points where the phase 2 gap had been about 12. That is not a scandal; it is what happens when a trial gets larger, longer and better controlled. Two more phase 3 trials, including a 5,531-participant cardiovascular outcomes study, have completed without posting results. There is no FDA-approved survodutide product.

By Grant Delaney, Research EditorAugust 2026

Highest phase reached

Phase 3

Largest completed trial

5,531enrolled, unreported

Longest reported duration

76weeks

FDA approval

Noneany indication

Compound

What it is

Survodutide is a single peptide that agonises two receptors: the glucagon receptor and the glucagon-like peptide 1 receptor. It has been tested in adults with obesity or overweight without diabetes, in adults with type 2 diabetes, in adults with biopsy-confirmed metabolic dysfunction-associated steatohepatitis and fibrosis stage F1 to F3, and in adults with obesity and at-risk metabolic dysfunction-associated steatotic liver disease. Boehringer Ingelheim funded every trial cited on this page.^1,2,3,4,5

Mechanism

How it works

Adding glucagon receptor agonism to GLP-1 receptor agonism is the design bet, and the trials that test it most directly are the liver ones rather than the weight ones. In a 48-week phase 2 trial of 293 participants with metabolic dysfunction-associated steatohepatitis and fibrosis, improvement in steatohepatitis without worsening of fibrosis occurred in 47%, 62% and 43% of the 2.4 mg, 4.8 mg and 6.0 mg groups against 14% on placebo — a response that did not increase monotonically with dose, and which the investigators fitted with a quadratic dose-response model. In the 216-participant SYNCHRONIZE-MASLD phase 3 trial, 84.2% of survodutide-treated patients reached a 30% or greater reduction in liver fat content on MRI at week 48 against 24.3% on placebo under the efficacy estimand, and 68.5% against 28.6% under the treatment regimen estimand.^3,4

Evidence

What the trials found

Randomized trials

Evidence strength: Randomized trials. Randomized controlled trials in humans, at scale.

The phase 2 obesity trial randomized 387 adults across 43 centres in 12 countries to 0.6, 2.4, 3.6 or 4.8 mg once weekly or placebo for 46 weeks, and reported mean weight changes of −6.2%, −12.5%, −13.2% and −14.9% against −2.8% on placebo. SYNCHRONIZE-1, the phase 3, randomized 725 adults with obesity and without diabetes 1:1:1 to survodutide titrated up to 3.6 mg or 6.0 mg or to placebo for 76 weeks, and reported −12.2%, −13.0% and −5.4% under the treatment-regimen estimand, with 72.6%, 71.9% and 46.3% of participants losing at least 5% of body weight. SYNCHRONIZE-MASLD randomized 216 adults with obesity and at-risk steatotic liver disease 2:1 to survodutide 6.0 mg or placebo for 48 weeks and met both coprimary endpoints, with mean weight change of −12.2% against −1.0% under the efficacy estimand and −8.7% against −1.4% under the treatment regimen estimand. In type 2 diabetes, a 16-week phase 2 trial of 413 participants found survodutide at 1.8 mg or more once weekly produced greater weight reduction than open-label semaglutide up to 1.0 mg, up to −8.7% against −5.3%. The phase 3 counterpart in type 2 diabetes, SYNCHRONIZE-2, randomized 752 treated participants across 133 sites in 19 countries 1:1:1 to survodutide up-titrated to 3.6 mg or 6.0 mg or to placebo, with the same coprimary endpoints at week 76 — and what has been published for it describes those baseline characteristics rather than the result.^1,2,4,5,6

14.9%

Weight loss, 4.8 mg — 46 wk (phase 2)

Against 2.8% on placebo; 233 of 386 treated participants completed the treatment period.

13.0%

Weight loss, 6.0 mg — 76 wk (phase 3)

SYNCHRONIZE-1, treatment-regimen estimand, against 5.4% on placebo.

5,531

Enrolled in the unreported outcomes trial

SYNCHRONIZE-CVOT, completed June 2026; no results posted on ClinicalTrials.gov as of Aug 2026.

—

Weight result in type 2 diabetes at 76 weeks

SYNCHRONIZE-2 completed April 2026; what has been published for it is a baseline-characteristics paper.

Weight change by trial, dose and timepoint (%)

Ph2 obesity 2.4 mg, 46 wk

12.5 %

Ph2 obesity 3.6 mg, 46 wk

13.2 %

Ph2 obesity 4.8 mg, 46 wk

14.9 %

Ph3 SYNCHRONIZE-1 3.6 mg, 76 wk

12.2 %

Ph3 SYNCHRONIZE-1 6.0 mg, 76 wk

13 %

Ph3 placebo, 76 wk

5.4 %

SYNCHRONIZE-2 (T2D)

No data

Trial size, participants enrolled

SYNCHRONIZE-MASLD

216

Ph2 MASH

293

Ph2 obesity

387

Ph2 type 2 diabetes

413

SYNCHRONIZE-1

725

SYNCHRONIZE-2

755

SYNCHRONIZE-CVOT

5531

How to read the evidence meter

Four steps, weakest to strongest. Most peptides sold for a goal light up one. We show the step the published human evidence actually reaches — not the step the seller implies.

AnecdotalUser reports and forum consensus. No controlled data.
Animal onlyRodent or cell studies. Nothing published in humans.
Early humanSmall, open-label, or phase 1/2 trials. Promising, unproven.
Randomized trialsRandomized controlled trials in humans, at scale.

Timeline

Development pipeline

Complete
Preclinical
Complete
Phase 1
Complete
Phase 2
Obesity (387), steatohepatitis (293) and type 2 diabetes (413) trials published
4 — Current step
Phase 3
2 of 6 completed trials published; SYNCHRONIZE-2 and the 5,531-participant CVOT unreported
5 — Not reached
FDA review & approval
No drugsFDA match, any indication

Summary

What the evidence does — and doesn't — support

Completed, not reported

SYNCHRONIZE-2 (NCT06066528, 755 participants, completed April 1, 2026) and SYNCHRONIZE-CVOT (NCT06077864, 5,531 participants, completed June 30, 2026) both show no posted results on ClinicalTrials.gov as of August 2026. For SYNCHRONIZE-2 the published paper describes baseline characteristics rather than outcomes.

What the evidence supports

Statistically significant weight reduction against placebo in a 725-participant phase 3 trial over 76 weeks
Dose-dependent weight reduction in a 387-participant phase 2 trial
Improvement in steatohepatitis without worsening of fibrosis in a 293-participant phase 2 liver trial
Reduction in MRI-measured liver fat in a 216-participant phase 3 liver trial, under both reported estimands

What it does not support

The 14.9% phase 2 figure as survodutide's expected effect — the phase 3 reported 13.0% at a higher dose over a longer trial
Any cardiovascular outcome claim — the 5,531-participant trial completed in June 2026 without posting results
A weight result in type 2 diabetes — SYNCHRONIZE-2 completed in April 2026 and its published paper describes baseline characteristics
A head-to-head ranking against semaglutide or tirzepatide at weight-management doses
A consumer supply chain — there is no FDA-approved survodutide product

Reality check

The catch

The phase 3 number came in below the phase 2 number, in both directions at once. Phase 2 reported −14.9% at 46 weeks on 4.8 mg against −2.8% on placebo, a gap of about 12 percentage points. SYNCHRONIZE-1 reported −13.0% at 76 weeks on a higher 6.0 mg dose against −5.4% on placebo, a gap of about 7.6. Two design facts explain much of that and are worth knowing before quoting either trial: the phase 2 analysed weight by the dose assigned at randomization with COVID-19-related discontinuations censored, and 233 of its 386 treated participants — 60.4% — completed the 46-week treatment period, while SYNCHRONIZE-1's primary analysis used a treatment-regimen estimand that explicitly incorporates early discontinuation, prohibited obesity medications and prolonged dose escalation. Neither number is wrong. They answer slightly different questions, and the phase 3 question is the harder one. Beyond that, the record simply stops: SYNCHRONIZE-2 (NCT06066528), 755 participants with obesity and type 2 diabetes, shows an actual completion date of April 1, 2026, and SYNCHRONIZE-CVOT (NCT06077864), 5,531 participants, an actual completion date of June 30, 2026; as of August 2026 ClinicalTrials.gov shows no posted results for either. A drugsFDA search returns no match for survodutide, for any indication — no approved label, no approved manufacturer, no dose a pharmacy can dispense and no legitimate consumer supply.

Dosing

Dosing evidence

Each trial ran its own ladder and none of them is a standard. The phase 2 obesity trial assigned 0.6, 2.4, 3.6 or 4.8 mg once weekly with a 20-week escalation followed by 26 weeks of maintenance. SYNCHRONIZE-1 titrated to 3.6 mg or 6.0 mg — a dose above anything the phase 2 tested — over 76 weeks. SYNCHRONIZE-MASLD used 6.0 mg once weekly for 48 weeks. The phase 2 trial in metabolic dysfunction-associated steatohepatitis assigned 2.4, 4.8 or 6.0 mg with a 24-week rapid escalation followed by 24 weeks of maintenance. The 16-week phase 2 trial in type 2 diabetes ran an entirely different range: up to 0.3, 0.9, 1.8 or 2.7 mg once weekly, or 1.2 or 1.8 mg twice weekly. Escalation speed is itself a variable under study here — the diabetes trial's authors concluded that dose-related gastrointestinal events could be mitigated with slower escalation. None of these is a recommendation, and there is no approved label to defer to.^1,2,3,4,5

Already have a dose in mind? Our reconstitution calculator converts it to syringe units. It does not suggest one.

Safety

Safety and side effects

Gastrointestinal events dominate and rise with dose. In the phase 2 obesity trial, adverse events occurred in 281 of 309 survodutide recipients (91%) against 58 of 77 on placebo (75%), and were primarily gastrointestinal in 232 of 309 (75%) against 32 of 77 (42%); 233 of 386 treated participants completed the 46-week treatment period. In SYNCHRONIZE-1, gastrointestinal symptoms — typically mild to moderate — were reported by 80.9% of the 3.6 mg group, 89.7% of the 6.0 mg group and 47.9% of the placebo group, and no deaths were reported. In the phase 2 steatohepatitis trial, nausea occurred in 66% of survodutide participants against 23% on placebo, diarrhoea in 49% against 23% and vomiting in 41% against 4%, with serious adverse events in 8% against 7%. In the 16-week diabetes trial, adverse events were reported for 77.8% of survodutide participants against 52.5% on placebo and 52.0% on semaglutide.^1,2,3,5

Sold for laboratory use. Not a legal medicine for people.

Three completed phase 3 trials, one published

As of August 2026 a ClinicalTrials.gov search for survodutide returns 24 studies, eight of them phase 3, and all eight sponsored by Boehringer Ingelheim. Six of the eight show a status of COMPLETED: SYNCHRONIZE-1 (NCT06066515, completed February 20, 2026), SYNCHRONIZE-2 (NCT06066528, 755 enrolled, completed April 1, 2026), SYNCHRONIZE-CVOT (NCT06077864, 5,531, completed June 30, 2026), SYNCHRONIZE-MASLD (NCT06309992, 218, completed December 2, 2025), a 274-participant Japanese trial completed December 3, 2025, and a 307-participant Chinese trial completed January 28, 2026. Two more, both in liver disease, are recruiting with estimated completion dates in 2029 and 2031.

None of those six shows posted results on ClinicalTrials.gov as of August 2026. Two of them have results papers in journals: SYNCHRONIZE-1 ² and SYNCHRONIZE-MASLD ⁴. For SYNCHRONIZE-2, what has been published is a paper describing the trial's baseline characteristics — 752 treated participants across 133 sites in 19 countries, mean age 55.7 years, mean body-mass index 36.5 — and stating that the trial will determine efficacy and safety, which is the language of a paper written before the results were available ⁶. That leaves the position as of August 2026: the largest survodutide dataset that exists is a 5,531-participant cardiovascular outcomes trial whose primary endpoint, per its registry record, is a non-inferiority comparison on a composite of cardiovascular death, non-fatal stroke, non-fatal myocardial infarction, ischaemia-related coronary revascularisation or a heart-failure event over up to 114 weeks — and its result is not yet in the public record.

The completion rate is part of the result

The phase 2 obesity trial is usually cited for its 14.9%. The same abstract reports that 233 of 386 treated participants — 60.4% — completed the 46-week treatment period, 187 of 309 on survodutide and 46 of 77 on placebo ¹. A trial where four in ten participants do not finish is still informative, but a mean computed under a planned-treatment analysis with COVID-19-related discontinuations censored is a different object from a mean computed under an estimand that keeps discontinuers in. SYNCHRONIZE-1 used the latter ². When a reader asks why the phase 3 number is smaller, the honest first answer is that it was measured more conservatively — and the second is that SYNCHRONIZE-1's placebo arm lost 5.4% ², roughly double the 2.8% lost by the phase 2 placebo arm ¹.

What survodutide has not been compared against

The published comparison against another drug in this class is narrow: a 16-week phase 2 trial in type 2 diabetes with an open-label semaglutide arm at up to 1.0 mg, where survodutide at 1.8 mg or more once weekly produced greater weight reduction ⁵. That is 16 weeks, in diabetes, against a semaglutide dose well below the 2.4 mg used for weight management on our semaglutide page, in an arm that was not blinded. Setting SYNCHRONIZE-1's −13.0% beside tirzepatide's −20.9% or semaglutide's −14.9% is a comparison across separate trials with different populations, durations and estimands, not a head-to-head result.

No approved product, and what that means here

A drugsFDA search returns no match for survodutide. There is no approved label, no approved dose, no approved manufacturer and no pharmacy that can dispense it. This page therefore names no supplier and describes no way to obtain it — for an unapproved molecule that would be a description of the grey market rather than a fact about the compound, and the identity and purity of anything sold under the name has been verified by no regulator.

Questions

Frequently asked questions

How much weight did people lose on survodutide?

In the phase 3 SYNCHRONIZE-1 trial, mean weight change at week 76 was −12.2% on 3.6 mg and −13.0% on 6.0 mg against −5.4% on placebo, under the treatment-regimen estimand. The earlier phase 2 trial reported −14.9% at 46 weeks on 4.8 mg against −2.8% on placebo. The phase 2 figure is the larger one, and it comes from the smaller, shorter, less conservatively analysed trial.

Why is the phase 3 number lower than the phase 2 number?

Two reasons visible in the published abstracts. The phase 2 analysed weight by the dose assigned at randomization with COVID-19-related discontinuations censored, and 233 of its 386 treated participants completed the 46-week treatment period. SYNCHRONIZE-1's primary analysis used a treatment-regimen estimand that incorporates early discontinuation, use of prohibited obesity medications and prolonged dose escalation. Its placebo arm also lost 5.4%, about double the phase 2 placebo arm's 2.8%, which narrows the gap the drug has to open.

Is survodutide FDA-approved?

A drugsFDA search returns no match for survodutide, for any indication, as of August 2026. Three of its phase 3 trials have completed — SYNCHRONIZE-1 in February 2026, SYNCHRONIZE-2 in April 2026 and a 5,531-participant cardiovascular outcomes trial in June 2026 — and of those three, SYNCHRONIZE-1 is the one with a published results paper. None of the three shows posted results on ClinicalTrials.gov as of August 2026. There is no public basis for predicting an approval outcome or date.

Does survodutide help fatty liver disease?

It has been tested twice. A 48-week phase 2 trial in 293 people with biopsy-confirmed steatohepatitis and fibrosis found improvement in steatohepatitis without worsening of fibrosis in 47%, 62% and 43% of the 2.4, 4.8 and 6.0 mg groups against 14% on placebo. The phase 3 SYNCHRONIZE-MASLD trial in 216 people met both coprimary endpoints, with 84.2% reaching at least a 30% reduction in liver fat on MRI against 24.3% on placebo under the efficacy estimand — 68.5% against 28.6% under the more conservative treatment regimen estimand. Its own authors list the 48-week duration and recruitment limited to the United States and Spain as limitations.

What dose of survodutide was studied?

Different ranges in different trials. Phase 2 in obesity: 0.6, 2.4, 3.6 or 4.8 mg once weekly. Phase 3 SYNCHRONIZE-1: titrated up to 3.6 mg or 6.0 mg. Phase 3 SYNCHRONIZE-MASLD: 6.0 mg. Phase 2 in steatohepatitis: 2.4, 4.8 or 6.0 mg. Phase 2 in type 2 diabetes: up to 0.3, 0.9, 1.8 or 2.7 mg once weekly, or 1.2 or 1.8 mg twice weekly. Those are trial assignments, not recommendations, and with no approved product there is no label dose to defer to.

What are survodutide's side effects?

Gastrointestinal events, rising with dose. In SYNCHRONIZE-1 they were reported by 80.9% of the 3.6 mg group and 89.7% of the 6.0 mg group against 47.9% on placebo, typically mild to moderate, with no deaths. In the phase 2 steatohepatitis trial, nausea occurred in 66% against 23% on placebo, diarrhoea in 49% against 23% and vomiting in 41% against 4%, with serious adverse events in 8% against 7%. The phase 2 diabetes trial's authors concluded that slower dose escalation could mitigate these events.

Glossary

Key terms

Dual agonist: One molecule that activates two receptors — here the glucagon receptor and the GLP-1 receptor — instead of one drug per receptor.
Treatment-regimen estimand: A way of defining the reported effect that keeps participants in the analysis even if they stop early or take a prohibited drug. It usually produces a smaller number than an on-treatment analysis.
Efficacy estimand: The effect estimated as if participants stayed on treatment as planned. SYNCHRONIZE-MASLD reported −12.2% under this and −8.7% under the treatment regimen estimand for the same arm.
Dose escalation: Stepping up gradually to a target dose to reduce side effects. Its speed is itself a variable — the diabetes trial's authors linked slower escalation to fewer gastrointestinal events.
Cardiovascular outcomes trial: A large trial counting real events — deaths, heart attacks, strokes — rather than a lab value or body weight. Survodutide's enrolled 5,531 people and has not reported.
MRI-PDFF: Magnetic resonance imaging proton density fat fraction: a scan-based measure of liver fat, used as the coprimary endpoint in SYNCHRONIZE-MASLD.

Sources

References

le Roux CW, Steen O, Lucas KJ, et al. (2024). Glucagon and GLP-1 receptor dual agonist survodutide for obesity: a randomised, double-blind, placebo-controlled, dose-finding phase 2 trial. The Lancet Diabetes & Endocrinology. https://pubmed.ncbi.nlm.nih.gov/38330987/
le Roux CW, Wharton S, Startseva E, et al. (2026). Survodutide Once Weekly for the Treatment of Adults with Obesity. New England Journal of Medicine. https://pubmed.ncbi.nlm.nih.gov/42253238/
Sanyal AJ, Bedossa P, Fraessdorf M, et al. (2024). A Phase 2 Randomized Trial of Survodutide in MASH and Fibrosis. New England Journal of Medicine. https://pubmed.ncbi.nlm.nih.gov/38847460/
Kaplan LM, Startseva E, le Roux CW, et al. (2026). Survodutide in adults with obesity and metabolic dysfunction-associated steatotic liver disease: SYNCHRONIZE-MASLD, a randomized, double-blind, placebo-controlled phase 3 trial. Nature Medicine. https://pubmed.ncbi.nlm.nih.gov/42252333/
Blüher M, Rosenstock J, Hoefler J, et al. (2024). Dose-response effects on HbA1c and bodyweight reduction of survodutide, a dual glucagon/GLP-1 receptor agonist, compared with placebo and open-label semaglutide in people with type 2 diabetes: a randomised clinical trial. Diabetologia. https://pubmed.ncbi.nlm.nih.gov/38095657/
Wharton S, le Roux CW, Bozkurt B, et al. (2026). Baseline characteristics in the SYNCHRONIZE-2 randomized phase 3 trial of survodutide, a glucagon receptor/GLP-1 receptor dual agonist, for obesity in people with type 2 diabetes. Diabetes, Obesity and Metabolism. https://pubmed.ncbi.nlm.nih.gov/41216778/

Medical disclaimer: This content is for general educational purposes only and is not medical advice, diagnosis, or treatment. Always consult a licensed healthcare professional before starting, stopping, or changing any treatment.