The Estimand Lesson
Survodutide
Also known as BI 456906
At a glance
- What it is
- Glucagon/GLP-1 dual agonist. Not approved anywhere; the numbers depend on the question.
- Evidence
- Clinical trialsHow the tiers workSYNCHRONIZE-1 (NEJM, 7 June 2026, n=725, NCT06066515) reported week-76 weight change on the treatment-regimen estimand as −12.2% on 3.6 mg and −13.0% on 6.0 mg against −5.4% on placebo, with 72.6%, 71.9% and 46.3% losing at least 5%. Why this tier
- Half-life
- Not established in available literature
- Routes
- Subcutaneous
- Category
- Metabolic
- WADA
- We do not state a status
Putting Survodutide on a schedule, with the vial it comes from and a log of each dose, happens in the app: Claritide for iPhone.
Why this tier
SYNCHRONIZE-1 (NEJM, 7 June 2026, n=725, NCT06066515) reported week-76 weight change on the treatment-regimen estimand as −12.2% on 3.6 mg and −13.0% on 6.0 mg against −5.4% on placebo, with 72.6%, 71.9% and 46.3% losing at least 5%. The press release and conference coverage headline the same trial as up to 16.6% weight loss against 3.2% placebo, with 85.1% reaching at least 5%. Both sets of numbers are true and they answer different questions. A separate Phase 3 in metabolic dysfunction-associated steatotic liver disease was published in Nature Medicine on the same day.
What it is
Survodutide is a glucagon receptor and GLP-1 receptor dual agonist from Boehringer Ingelheim and Zealand Pharma, given once weekly by subcutaneous injection. It is not approved anywhere and is available only through gray-market channels. It is also the cleanest teaching case we have for how the same trial produces two different headline numbers depending on which question is asked.
How it works
Survodutide activates two receptors. The GLP-1 arm does the familiar work: appetite suppression through the brain, slowed gastric emptying, glucose-dependent insulin release. The glucagon arm is the addition: glucagon receptor agonism increases energy expenditure and drives hepatic fat oxidation, which is why the dual agonists are being trialled in liver disease as well as obesity. Glucagon on its own would raise blood sugar; simultaneous GLP-1 activation counterbalances that.
Commonly researched ranges
- Phase 3 maintenance doses (SYNCHRONIZE-1)3.6–6 mg
Two doses, not a band: NCT06066515 studied 3.6 mg and 6.0 mg over 76 weeks and nothing in between. The titration up to them is described as extended and flexible, and its steps are not published, so no intermediate figure exists to show. Investigational; there is no approved regimen.
| Phase | Amount | Frequency | Timing | Note |
|---|---|---|---|---|
| Phase 3 maintenance doses (SYNCHRONIZE-1) | 3.6–6 mg | Once weekly, after titration | Not established in available literature | Two doses, not a band: NCT06066515 studied 3.6 mg and 6.0 mg over 76 weeks and nothing in between. The titration up to them is described as extended and flexible, and its steps are not published, so no intermediate figure exists to show. Investigational; there is no approved regimen. |
- Cycle guidance
- Not established in available literature
- Goals
- Fat loss
Where this sits with the FDA
Survodutide is in Phase 3 development and is not approved anywhere. It appears in gray-market channels, which means anything obtained outside a trial has no manufacturer, no label and no chain of custody.
Primary sourceWADA status
Not named on the 2026 Prohibited List. Semaglutide and tirzepatide sit on the Monitoring Program rather than the List; we could not determine survodutide’s classification and do not state one.
We looked and could not resolve it. This is not the same as "not prohibited". Treat it as unresolved and check with your federation before competing.
Mixing recipes our sources document
Not established in available literature. Use the calculator with the figures printed on your own vial.
Open the calculator
Week by week
Not established in available literature.
Side effects
Common
- Gastrointestinal adverse events89.7% in trials
Contraindications and interactions
Do not use if
Not established in available literature.
Interactions
Not established in available literature.
Absence from this list does NOT mean safety. It means lack of research.
Storage and cost
- Storage
- Our sources publish no reconstitution or storage protocol for survodutide.
- Cost
- Not established in available literature
Survodutide in full
Limited coverage
Survodutide is a glucagon receptor and GLP-1 receptor dual agonist from Boehringer Ingelheim and Zealand Pharma. Once weekly, subcutaneous, titrated to 3.6 mg or 6.0 mg. Not approved anywhere.
Why it is here
Because of what its Phase 3 shows about reading trial results.
SYNCHRONIZE-1, published in the New England Journal of Medicine on 7 June 2026, 725 participants, NCT06066515. At week 76, on the treatment-regimen estimand, weight change was −12.2% on 3.6 mg and −13.0% on 6.0 mg, against −5.4% on placebo. At least 5% loss was achieved by 72.6%, 71.9% and 46.3% respectively.
The press release and the conference coverage of the same trial headline up to 16.6% weight loss at 76 weeks against 3.2% placebo, with 85.1% reaching at least 5%.
Neither set is wrong. They are different estimands, different formal questions asked of the same data. Roughly: "what happened to everyone randomised, including people who stopped or added another drug" versus "what happens if you take it as directed and keep taking it". The first is what you would expect in the world. The second is what the drug can do under ideal conditions.
Almost every weight-loss figure you will see quoted somewhere is one of these two, and almost nobody says which.
Tolerability
Gastrointestinal adverse events ran 80.9% on 3.6 mg and 89.7% on 6.0 mg, against 47.9% on placebo, typically mild to moderate, with no deaths. That is a high GI burden even for this class.
A separate Phase 3 in metabolic dysfunction-associated steatotic liver disease was published in Nature Medicine on the same day, reflecting where the glucagon arm is expected to matter most.
Sources
- 1NEJM, 7 June 2026 · SYNCHRONIZE-1, survodutide in obesity, n=725
- 2ClinicalTrials.gov NCT06066515 · SYNCHRONIZE-1, Boehringer Ingelheim (completed; no results posted to the registry; read 27 September 2026)
- 3Nature Medicine, 7 June 2026 · survodutide Phase 3 in MASLD
- 4Boehringer Ingelheim · SYNCHRONIZE-1 results announcement
- 5SYNCHRONIZE-1/-2 design paper · the 3.6 mg and 6.0 mg maintenance doses, with titration described but its steps unpublished (dose review, 2026-08-17)
Every record in this library is free to read, and it stays free. Your own schedule, vials and log live in the app: Claritide for iPhone.