Survodutide: The GLP-1/Glucagon Dual Agonist for Weight and Liver | Philadelphia

TL;DR30-second take

Survodutide is an investigational weekly injection from Boehringer Ingelheim and Zealand Pharma that activates two receptors: GLP-1, which curbs appetite, and glucagon, which raises energy burning and acts on the liver. It is not the same as tirzepatide, which pairs GLP-1 with GIP, or retatrutide, which adds a third receptor. In its phase 3 obesity trial, SYNCHRONIZE-1, reported in 2026, it produced about 16.6% weight loss over 76 weeks. Its standout feature is the liver: in a phase 2 trial in MASH, the scarring form of fatty liver disease, it improved the disease on biopsy in far more people than placebo, which earned it a breakthrough therapy designation. It is not yet FDA-approved, its liver benefit rests on biopsy rather than long-term outcomes, and the glucagon action can raise heart rate.

TL;DR: Survodutide is an investigational once-weekly injection from Boehringer Ingelheim and Zealand Pharma. Where semaglutide targets one receptor and tirzepatide targets two (GIP and GLP-1), survodutide targets a different pair: GLP-1, which curbs appetite, and glucagon, which raises energy burning and acts directly on the liver. In its phase 3 obesity trial, SYNCHRONIZE-1, reported in 2026, it produced about 16.6% weight loss over 76 weeks, a strong number that sits below the highest emerging drugs on weight alone. What sets it apart is the liver. In a phase 2 trial in MASH, the inflammatory and scarring form of fatty liver disease, it improved the disease on biopsy in far more people than placebo, up to 62% at the best dose versus 14% on placebo in the published primary analysis, and as high as 83% in a more permissive analysis, which earned it a breakthrough therapy designation from the FDA. As of mid-2026 it is still investigational, its liver benefit rests on biopsy rather than proven long-term outcomes, and its glucagon action can raise heart rate.

What is survodutide, and how is it different from the other new drugs?

Survodutide is a once-weekly injection that mimics two of the body's hormones at once. The first is GLP-1, the same appetite-and-glucose hormone behind Ozempic, Wegovy, and the rest of the class. The second is glucagon, which is a departure from the other drugs. Glucagon raises how much energy the body burns and, importantly, acts on the liver to reduce liver fat.

That pairing is what distinguishes it. Semaglutide uses GLP-1 alone. Tirzepatide, in Zepbound and Mounjaro, pairs GLP-1 with a different hormone, GIP. Retatrutide adds a third receptor, combining GIP, GLP-1, and glucagon in one molecule. Survodutide sits between them: it takes the glucagon idea that retatrutide uses, but pairs it with GLP-1 alone, without GIP. The molecule is also designed to weigh more heavily on the GLP-1 side, so the glucagon effect is added on top of a GLP-1 backbone rather than dominating it.

It is developed by Boehringer Ingelheim, with the peptide designed by Zealand Pharma. As of mid-2026 it is investigational, meaning it is still in trials and has not been approved by the FDA for any use.

How much weight does survodutide cause?

The number to anchor on comes from its phase 3 obesity trial, SYNCHRONIZE-1, which reported in 2026. In it, adults with obesity or overweight lost about 16.6% of their body weight over 76 weeks at the studied dose, compared with about 3% on placebo, and roughly 85% of people lost at least 5% of their weight.¹ A more conservative count that includes people who stopped the drug put the average closer to 13%. That is a strong result, in the range of the approved drugs, and it is the figure that should anchor any expectation, because a phase 3 trial is larger and more rigorous than the earlier phase 2 work.

The phase 2 trial that came before it had suggested a similar or slightly higher figure, around 15% to 19% depending on how the analysis counted people who stopped early, over 46 weeks, and weight was still declining at the end rather than leveling off.² One caution from that phase 2 trial is worth carrying forward: the dose was raised quickly, every two weeks, and about a quarter of people stopped the drug, mostly because of nausea. A slower dose climb is one of the things the later trials worked to improve.

A fair reading is that survodutide produces weight loss in the same league as the leading drugs, though on weight alone it does not top the highest numbers reported for retatrutide or the tirzepatide-based combinations. Its case does not rest on being the strongest for weight. It rests on the liver.

What makes survodutide interesting for the liver?

This is the heart of the drug. The glucagon half of survodutide acts directly on liver cells to burn and clear fat, which is why the program has focused so heavily on fatty liver disease, and specifically on MASH, short for metabolic dysfunction-associated steatohepatitis, the stage where liver fat has driven inflammation and scarring.

In a phase 2 trial in people with MASH and fibrosis, survodutide improved the disease on biopsy, meaning the steatohepatitis got better without the scarring getting worse, in far more people than placebo.³ In the published primary analysis, the disease improved in up to 62% of people at the best dose, versus 14% on placebo. A more permissive analysis, limited to people who reached and tolerated the target dose, put the figure as high as 83%, versus about 18% on placebo. Either way, the gap over placebo was wide, which is what drew attention. Liver fat fell by at least 30% in roughly two-thirds of people, far more than on placebo.

The scarring result was more measured. Fibrosis improved by at least one stage, without the inflammation worsening, in about 34% to 36% of people on survodutide versus 22% on placebo, a genuine gain but a modest one, in line with what other drugs show for scarring over this length of time. On the strength of the MASH data, the FDA granted survodutide a breakthrough therapy designation for MASH in 2024, which speeds up review but is not the same as approval.

Two honest limits keep this in proportion. First, the MASH result comes from a biopsy at about a year; it shows the drug improves the liver's biology and appearance, but it has not yet been shown to prevent the outcomes that matter most, cirrhosis, liver failure, and death. Those hardest outcomes are chiefly what the companion phase 3 trial in people who already have cirrhosis, LIVERAGE-Cirrhosis, is built to test, and it has not reported; the main LIVERAGE trial, in people without cirrhosis, is anchored on liver biopsy. Second, this is still a phase 2 liver result awaiting phase 3 confirmation.

What are the trade-offs and side effects?

The side effects are led by the gut, as with the whole class: nausea, vomiting, and diarrhea, heaviest during the weeks when the dose is being raised. In the phase 2 obesity trial these were common, and the rapid dose escalation used there pushed the discontinuation rate to about a quarter, higher than what is seen with a slower climb. The later trials use a gentler schedule to soften this.

The glucagon component adds its own consideration. Glucagon tends to raise heart rate, and survodutide did produce a modest, dose-related rise in the trials, though without a signal of dangerous rhythm problems. Glucagon can also, in theory, raise blood sugar, but the GLP-1 half appears to offset that, and the trials did not show worsened glucose control. Even so, the heart-rate effect is part of why the drug is being studied carefully, and why its cardiovascular outcome trial matters.

Where does survodutide fit among the new drugs?

Think of it as the liver-forward member of the next wave. Retatrutide is the one to watch for sheer weight loss, adding glucagon on top of GIP and GLP-1. CagriSema pairs GLP-1 with a different hormone, amylin, and reaches around 22% for weight. Survodutide takes the glucagon route but leans it toward the liver, which is why it, rather than the amylin drug, carries a dedicated MASH program and a breakthrough designation for liver disease.

For a person whose central problem is MASH, particularly one who also carries excess weight, survodutide is a drug to follow closely. For someone whose goal is the largest possible weight loss, the triple agonist and the tirzepatide-based options currently report higher numbers. None of these comparisons come from head-to-head trials, though, so they are rough guides across separate studies rather than direct contests. And all of it is forward-looking: survodutide is not approved, and the drugs proven and available today remain the foundation of care.

Guidance from the Clinic

"Patients who follow this space ask me about survodutide because of the liver data, and that is the right instinct. The weight-loss number is strong but not the headline; the story here is the glucagon receptor and what it does for a fatty, scarred liver. What I keep clear is that the impressive MASH result is a biopsy result at a year, not proof that it prevents cirrhosis or extends life, and that the trial testing those hard outcomes has not reported. I also make sure people know it is not approved, that a breakthrough designation is a faster review rather than a green light, and that the glucagon action nudges heart rate up, which we would watch. For the right patient down the line, a drug that treats weight and the liver together through glucagon could be a valuable addition. For today, I build the plan around what is proven and keep an eye on this as it moves."

Key Takeaways

Survodutide is an investigational once-weekly injection from Boehringer Ingelheim and Zealand Pharma that activates two receptors, GLP-1 and glucagon, without the GIP that tirzepatide and retatrutide use.
In its phase 3 obesity trial, SYNCHRONIZE-1, reported in 2026, it produced about 16.6% weight loss over 76 weeks, a strong result that sits below the highest emerging drugs on weight alone.
Its standout feature is the liver: in a phase 2 MASH trial it improved the disease on biopsy in up to 62% of people at the best dose versus 14% on placebo in the published primary analysis, and as high as 83% in a more permissive analysis, earning a breakthrough therapy designation.
The liver benefit rests on biopsy at about a year rather than on proven long-term outcomes; a phase 3 trial, LIVERAGE, is testing whether it prevents cirrhosis and death and has not reported.
It is not FDA-approved, its main side effects are gastrointestinal, and the glucagon action raises heart rate, which its cardiovascular outcome trial is examining.

The New Weight-Loss Drugs, Compared - where survodutide sits in the whole field
Retatrutide: The Triple Agonist - the glucagon-containing drug with the highest weight loss
CagriSema (Cagrilintide + Semaglutide) - the amylin combination, another next-wave drug
Semaglutide (Wegovy) for MASH - an approved GLP-1 for fatty liver
Resmetirom (Rezdiffra): The First MASH Drug - the liver-direct drug already approved
Fatty Liver (MASLD/MASH) - the disease and the metabolic work underneath it
Mazdutide (GLP-1/Glucagon) - the other GLP-1/glucagon drug, approved in China

Scientific References

le Roux CW, et al. "Survodutide Once Weekly for the Treatment of Adults with Obesity." New England Journal of Medicine. 2026. DOI: 10.1056/NEJMoa2600751. Presented at the American Diabetes Association Scientific Sessions, June 2026.
le Roux CW, Steen O, Lucas KJ, et al. "Glucagon and GLP-1 Receptor Dual Agonist Survodutide for Obesity: A Randomised, Double-Blind, Placebo-Controlled, Dose-Finding Phase 2 Trial." Lancet Diabetes & Endocrinology. 2024;12(3):162-173.
Sanyal AJ, Bedossa P, Fraessdorf M, et al. "A Phase 2 Randomized Trial of Survodutide in MASH and Fibrosis." New England Journal of Medicine. 2024;391(4):311-319.

Fishtown Medicine | Metabolism

2418 E York St, Philadelphia, PA 19125(267) 360-7927 hello@fishtownmedicine.comHSA/FSA Eligible

Start your intake

Frequently Asked Questions

Common Questions

No. As of mid-2026, survodutide is investigational, meaning it is still being studied in trials and has not been approved by the FDA for weight loss, diabetes, or liver disease. It has a breakthrough therapy designation for MASH, which speeds up the FDA's review but is not an approval and does not make the drug available. The drugs used in practice today are the approved GLP-1 and dual-agonist medications.

In its phase 3 obesity trial, SYNCHRONIZE-1, reported in 2026, people lost about 16.6% of their body weight over 76 weeks, versus about 3% on placebo, with roughly 85% losing at least 5%. That is a strong result, in the range of the approved drugs, though below the highest numbers reported for retatrutide or the tirzepatide-based combinations. Because there are no head-to-head trials, those cross-drug comparisons are approximate.

Survodutide activates the glucagon receptor in addition to GLP-1. Semaglutide (Ozempic, Wegovy) uses GLP-1 alone; tirzepatide (Zepbound, Mounjaro) pairs GLP-1 with GIP. The glucagon action raises energy burning and, most notably, acts directly on the liver to clear fat, which is why survodutide has been developed heavily for fatty liver disease. It does not use GIP, which sets it apart from tirzepatide and from the triple agonist retatrutide.

Because the glucagon receptor it activates sits on liver cells and drives them to burn and clear fat. That gives survodutide a direct route to reduce liver fat, on top of the weight loss and better blood sugar it shares with the other drugs. In a phase 2 trial in MASH, the scarring form of fatty liver disease, it improved the disease on biopsy in far more people than placebo, which is why it carries a breakthrough therapy designation for MASH and a dedicated phase 3 liver program.

Not yet. The phase 2 MASH result is based on a liver biopsy at about a year, showing the drug improves the liver's inflammation and, more modestly, its scarring. It has not been shown to prevent the outcomes that matter most, cirrhosis, liver failure, and death. A large phase 3 trial called LIVERAGE is testing those long-term outcomes, and it has not reported. So the fair statement is that survodutide improves the liver on biopsy, with its effect on long-term liver health still being tested.

Deep-Dive Questions

This is the clever part of the design. Glucagon is best known for raising blood sugar, which sounds like the opposite of what a metabolic drug should do. But glucagon also raises energy expenditure and acts on the liver to burn fat, and those are the effects survodutide is after. The trick is pairing it with GLP-1, which lowers appetite and improves blood sugar, so the GLP-1 side offsets glucagon's tendency to raise glucose while the glucagon side adds fat burning and the liver effect. In the trials, glucose control did not worsen, which suggests the balance works as intended. It is a case of using two opposing hormones so their useful effects add up and their unwanted ones cancel.

Because retatrutide engages more pathways. Retatrutide is a triple agonist, hitting GIP, GLP-1, and glucagon, while survodutide hits two, GLP-1 and glucagon, without GIP. In general, the more of these hunger-and-metabolism receptors a drug engages, and the more fully it engages them, the more weight loss it tends to produce, which is why the triple agonist reports the highest numbers and the single-receptor drugs the lowest. Survodutide's design also weighs more heavily toward GLP-1, with glucagon added on top, and its development has prioritized the liver rather than pushing the weight number as high as possible. So the lower weight figure reflects both fewer receptors and a different goal rather than a weaker drug for its intended purpose.

Carefully, because the trial reported more than one. The published primary analysis, the one in the medical journal, put the best dose at about 62% of people improving versus 14% on placebo. A more permissive analysis, which counted only people who reached and stayed on the target dose, put the figure as high as 83%, against about 18% on placebo. All of these are valid, and all show a wide gap over placebo, which is the point. But a reader who sees only 83% may take away more than the plainer, primary number supports. The fair framing is that survodutide improved MASH on biopsy in a majority of treated people and far more than placebo, with the exact percentage depending on how the trial counted and which dose is meant.

Two readouts. The first is the phase 3 liver program, LIVERAGE, whose companion trial in people who already have cirrhosis is testing the hardest outcomes, whether the drug reduces progression to liver failure, transplant, or death, while the main trial in people without cirrhosis tracks the liver on biopsy. These are the outcomes a single biopsy cannot prove on its own. The second is the cardiovascular outcome trial in the SYNCHRONIZE program, which will show whether the drug is safe for the heart over the long run, an important question given the glucagon-driven rise in heart rate. Approval for weight is likely to come first, on the strength of the phase 3 obesity data, but the liver and heart outcome trials are what would establish survodutide as a drug that changes the course of disease rather than just the numbers.

Ready when you are