Mazdutide: The GLP-1 and Glucagon Dual Agonist Approved in China

Mazdutide is the compound most people in this niche have not heard of yet, and it is further along than that suggests. It is approved for weight management in China, it has a completed phase 3 trial published in the New England Journal of Medicine, and it works through a receptor combination nothing else on the approved market uses.

This page covers what it is, what GLORY-1 measured, how it compares with the compounds people already know, and the specific caveats that come with a drug approved in one country and investigational everywhere else. For the wider class see weight loss peptides. This is research use information and none of it is medical advice.

What Mazdutide Is

Mazdutide, developed under the code IBI362 by Innovent Biologics under licence from Eli Lilly, is a once-weekly injectable dual agonist of the GLP-1 receptor and the glucagon receptor. It is based on oxyntomodulin, a gut hormone that naturally activates both.

The receptor combination is the interesting part, and it is worth understanding because it explains both the appeal and the caution. Semaglutide hits GLP-1 alone. Tirzepatide hits GIP and GLP-1. Retatrutide hits GIP, GLP-1 and glucagon. Mazdutide hits GLP-1 and glucagon, and skips GIP.

Glucagon receptor agonism is what separates it from semaglutide and tirzepatide. GLP-1 and GIP agonism reduce how much you eat. Glucagon agonism raises energy expenditure and promotes hepatic fat mobilisation, so it works on the other side of the equation. That is the mechanistic reason retatrutide produced the largest figure in the class, and mazdutide gets at the same lever by a different route.

What GLORY-1 Measured

GLORY-1 was a randomised, double-blind, placebo-controlled phase 3 trial in 610 Chinese adults with overweight or obesity, running 48 weeks.

Two caveats matter for reading those numbers against the figures people know from SURMOUNT and STEP. GLORY-1 ran 48 weeks rather than 68 or 72, and the GLP-1 class curves are still descending at 48 weeks, so this is not a like-for-like endpoint. And the trial enrolled Chinese adults, whose mean baseline body weight and BMI were substantially lower than in SURMOUNT-1, which changes what a given percentage represents and limits how far the result generalises.

What the result does establish is that mazdutide is a serious compound rather than a fringe one. A 13.4 percent mean reduction at 48 weeks sits it comfortably alongside semaglutide and below tirzepatide, on a trial that has been published and peer reviewed.

Mazdutide vs Retatrutide

This is the comparison people actually search for, because both are glucagon-containing agonists and both sit outside the approved US market.

Retatrutide adds GIP on top of what mazdutide does, and produced 24.2 percent mean reduction at 48 weeks at 12mg in its phase 2 trial, against mazdutide's 13.4 percent at 6mg over the same period. On the face of it retatrutide is substantially stronger, and probably is, though the trials were run in different populations and were never compared head to head, so the gap is indicative rather than measured.

The meaningful difference is regulatory rather than pharmacological. Mazdutide has completed phase 3 and is an approved medicine in one of the largest pharmaceutical markets in the world. Retatrutide is still investigational everywhere, with phase 3 ongoing. So mazdutide has cleared a bar retatrutide has not, even though its headline number is lower. See the retatrutide guide and tirzepatide vs retatrutide.

Side Effects

The profile reported in the trials is the familiar one for this class and dominated by gastrointestinal effects: nausea, diarrhoea, vomiting and reduced appetite, mostly mild to moderate and concentrated during dose escalation.

The glucagon component adds a consideration the pure GLP-1 drugs do not have. Glucagon receptor agonism can raise heart rate and, in principle, affect hepatic glucose output and liver enzymes, and those are the parameters the trial programmes for glucagon-containing agonists watch most closely. This is a drug where the mechanism that produces the extra effect is also the one that warrants the extra monitoring.

The Sourcing Problem

Be clear about the regulatory position, because it is unusual and it is the most important practical fact on this page.

Mazdutide is an approved prescription medicine in China. It is not FDA approved, not EMA approved, and there is no legitimate prescription route to it in the United States, the UK or the EU. Anything sold as mazdutide outside China is either a research chemical or a personal import, and neither is a regulated product.

That has a specific consequence for research buyers. With tirzepatide or semaglutide there is at least an approved reference product to compare a vial against, and a large market that makes counterfeiting comparatively detectable. With mazdutide there is very little of that, the compound is unfamiliar enough that few buyers know what to check, and the vendor base carrying it is small. A lot-specific certificate of analysis with the assay method stated is the only signal available, and it matters more here than usual.

PSPeptides is the vendor in our scorecard that carries mazdutide, and it is the only one we track that ships outside the United States. We have not published a verified price per milligram for this compound, so check the live listing rather than any figure quoted elsewhere. Our scoring across every vendor is in the vendor scorecard, and reconstitution arithmetic is in the reconstitution calculator with syringe reading in how to read an insulin syringe.

Who This Is Actually Relevant To

Honestly, for most people the answer is nobody yet. If you are in the United States or Europe and want a glucagon-containing agonist, the practical options are retatrutide through the research route or waiting. If you want a compound with the strongest approved evidence, that is tirzepatide. Mazdutide's distinguishing feature is that it is approved somewhere, which matters a great deal if you are in China and very little if you are not.

Where it is genuinely interesting is as a signal about where the class is going. GLORY-1 is further evidence that adding glucagon agonism to GLP-1 produces more weight loss than GLP-1 alone, which is the same conclusion retatrutide's phase 2 pointed at. Two independent compounds arriving at that from different directions is a stronger finding than either one alone.

Key Takeaways

• Mazdutide is a once-weekly GLP-1 and glucagon dual agonist based on oxyntomodulin, developed by Innovent under licence from Eli Lilly.
• GLORY-1, a 610 participant phase 3 trial, produced -10.97% at 4mg and -13.38% at 6mg over 48 weeks.
• That trial ran 48 weeks in Chinese adults, so it is not a like-for-like comparison with the 68 and 72 week Western trials.
• It is approved for weight management in China and is not FDA or EMA approved.
• Retatrutide adds GIP and produced a larger figure, but has not completed phase 3.
• The glucagon component is what adds effect and what warrants extra monitoring, particularly heart rate and liver parameters.
• Outside China there is no legitimate prescription route, and the small unfamiliar market makes verification harder than for better-known compounds.

Frequently Asked Questions

What is mazdutide?

Mazdutide, developed as IBI362 by Innovent Biologics under licence from Eli Lilly, is a once-weekly injectable dual agonist of the GLP-1 and glucagon receptors, based on the gut hormone oxyntomodulin. The glucagon component is what distinguishes it from semaglutide and tirzepatide: GLP-1 and GIP agonism reduce energy intake, while glucagon agonism raises energy expenditure and promotes hepatic fat mobilisation.

How much weight loss does mazdutide produce?

In GLORY-1, a 610 participant phase 3 trial in Chinese adults with overweight or obesity, mazdutide produced a mean weight reduction of 10.97 percent at 4mg and 13.38 percent at 6mg over 48 weeks. Two caveats: the trial ran 48 weeks rather than the 68 or 72 weeks used in the Western trials, and it enrolled a population with a substantially lower mean baseline weight, so it is not a like-for-like comparison.

Mazdutide vs retatrutide: which is stronger?

Retatrutide produced a larger figure, 24.2 percent at 12mg over 48 weeks in phase 2 against mazdutide's 13.38 percent at 6mg. Retatrutide adds GIP agonism on top of the GLP-1 and glucagon combination that mazdutide uses. The two have never been compared head to head, so the gap is indicative rather than measured. The meaningful difference is regulatory: mazdutide has completed phase 3 and is approved in China, while retatrutide is still investigational everywhere.

Is mazdutide FDA approved?

No. Mazdutide is approved for weight management in China and is not approved by the FDA or the EMA. There is no legitimate prescription route to it in the United States, the UK or the EU, so anything sold under that name outside China is either a research chemical or a personal import, neither of which is a regulated product.

What are the side effects of mazdutide?

The reported profile is the familiar one for this drug class and is dominated by gastrointestinal effects: nausea, diarrhoea, vomiting and reduced appetite, mostly mild to moderate and concentrated during dose escalation. The glucagon component adds considerations the pure GLP-1 drugs do not have, principally heart rate and hepatic parameters, which are what the trial programmes for glucagon-containing agonists monitor most closely.

Where can you buy mazdutide?

Outside China there is no prescription route, so the only availability is through research peptide vendors. Of the vendors in our scorecard, PSPeptides carries it. Verification is harder for mazdutide than for better-known compounds, because the market is small, buyers are generally unfamiliar with it, and there is no widely available approved reference product to compare against. A lot-specific certificate of analysis with the assay method stated is the only meaningful signal.