Mazdutide (also called IBI362) is a synthetic peptide that activates both the GLP-1 and glucagon receptors. Innovent Biologics and Eli Lilly developed it together. It is given as a once-weekly injection under the skin.

China's National Medical Products Administration (NMPA) has approved it for chronic weight management and type 2 diabetes. The FDA has never reviewed or approved it. In the US it is not a legally marketed drug and reaches buyers only as an unregulated research chemical.

Research peptides

Mazdutide: What It Is, Benefits, Dosage and Side Effects

Mazdutide (IBI362): a GLP-1/glucagon dual agonist peptide approved in China for weight management and diabetes, not FDA-approved in the US.

Written bySebastian Hunter, Founder and EditorI'm a 42-year-old senior advisor and distance runner who came to peptides as a sceptic. I'm not a doctor: I read the research, run my own experiment and keep honest notes. Read full bio

Published September 28, 2026Updated October 1, 2026

The short version

Mazdutide is a peptide that activates both the GLP-1 and glucagon receptors, developed by Innovent Biologics with Eli Lilly. China's NMPA has approved it for chronic weight management and for type 2 diabetes, each after its own phase 3 programme in Chinese adults. The FDA has never reviewed it, and in the US it is sold only as an unregulated research chemical.

Approved in China (NMPA) for chronic weight management and blood-sugar control in type 2 diabetes; not FDA-approved.
A US phase 2 trial and Chinese phase 3 trials reported weight loss and glucose control that rose with the dose.
The research-chemical market has a common-practice protocol, but no trial or prescriber set it.
A foreign approval doesn't mean a regulator checks that a US research vial matches its label.

Mazdutide at a glance

What it is: Dual GLP-1/glucagon receptor agonist, a peptide, co-developed by Innovent Biologics and Eli Lilly
Main use: Approved in China for chronic weight management and for glycemic control in type 2 diabetes. Not FDA-approved in the United States, where it is sold to consumers as a research-chemical vial.
Also called: IBI362, LY3305677
Molecular formula: C210H322N46O67 (4563.1 g/mol) Structure
Evidence: Moderate human evidence
US status: Research use only
Half-life: Not established in humans
How it is taken: Subcutaneous injection
Common protocol: 3-9 mg, once weekly, titrated upward from a lower starting dose, for 24 weeks (common practice, not trial-established) Dosage chart

Dosing: the common protocol and trial doses.

Moderate human evidence

Multiple randomised trials, though with limitations. A US-based, multicentre, placebo-controlled phase 2 trial reported dose-ranging efficacy and safety data. China's NMPA has since approved mazdutide after its own phase 3 programme in Chinese adults. That is real regulatory review, but not FDA review, and I did not verify every phase 3 claim against a peer-reviewed paper.

What is mazdutide?

Mazdutide (IBI362 in trial papers) is a synthetic peptide that activates both the GLP-1 receptor and the glucagon receptor. Innovent Biologics and Eli Lilly developed it together, and it is given as a once-weekly injection under the skin.

It belongs to the same broad family as semaglutide, tirzepatide, cagrilintide, retatrutide and survodutide. Each combines a different set of receptor targets.

US legal status - Research use only

Not FDA-approved for any use. Sold to US consumers as a research chemical, outside any reviewed supply chain.

Mazdutide structure

Molecular formula: C₂₁₀H₃₂₂N₄₆O₆₇
Molecular weight: 4563.1 g/mol
Length: 34 amino acids
Sequence: HXQGTFTSDYSKYLDEKKAKEFVEWLLEGGPSSG
Modifications: X at position 2 = Aib; Lys20 carries a C20 fatty diacid via a gamma-Glu-2xOEG linker; C-terminal glycinamide.

PubChem's "Mazdutide" record (CID 167312357) has a formula (C207H317N45O65) that does not match KEGG's C210H322N46O67, so no diagram is shown.

Sequence checked against FDA Global Substance Registration System (UNII MB76Z4IBZ5).

Mazdutide benefits: what the research shows

A US-based, multicentre, placebo-controlled phase 2 trial in adults with obesity or overweight (Hsia 2026 - Hsia SH, Bays HE, Billings LK et al. Efficacy and safety of mazdutide in adults with obesity or overweight: a US-based, multicentre, phase 2, randomised, placebo-controlled clinical trial. Lancet Diabetes Endocrinol. 2026., in the references below) found that weight loss rose with the dose. Its gut side effects matched other GLP-1 drugs.

China’s NMPA then approved mazdutide twice, each time after its own phase 3 programme in Chinese adults:

June 2025: chronic weight management.
September 2025: blood-sugar control in type 2 diabetes. One of the trials behind it compared mazdutide with dulaglutide (Guo 2026 - Guo L, Zhang B, Xue X et al. Mazdutide versus dulaglutide in Chinese adults with type 2 diabetes. Nature. 2026;652(8108):181-188., in the references below).

That is a real approval by a real regulator. It is not an FDA approval, and this page doesn’t treat the two as the same.

Mazdutide dosage

The common Mazdutide dose is 3-9 mg, once weekly, titrated upward from a lower starting dose. From a 10 mg vial mixed with 1 mL of bacteriostatic water, 6 mg is 60 units (0.6 mL) on a U-100 insulin syringe.

See the full Mazdutide dosage chart →

No dose is FDA-approved. China’s phase 3 trials tested 4 mg and 6 mg weekly, and separately 9 mg weekly in people with moderate-to-severe obesity. Research-market sources describe a common-practice pattern that no trial established. Full sourcing: mazdutide dosage.

Mazdutide side effects

Nausea, vomiting and diarrhoea are the most common side effects across the phase 2 and phase 3 trials. They are generally more frequent at higher doses, as with other GLP-1 drugs. Full detail: mazdutide dosage.

Is mazdutide legal?

US legal status - Research use only

Sold for laboratory research use only. Not approved by the FDA for human use, and cannot be lawfully marketed as a supplement or a medicine. Products sold this way are not made to pharmaceutical quality standards, and their contents are not verified by anyone.

China’s NMPA has approved it for two uses. In the US it is not FDA-approved and not a legally marketed drug; it is sold only as a research chemical outside any reviewed supply chain. I didn’t check its status in other countries, including Australia.

More on where research peptides stand under US law: US peptide regulation tracker.

How Mazdutide compares

GLP-1 and related medicines. Doses for unapproved compounds are common practice, not trial-established. All weight loss and metabolism peptides →

Compound	Main use	Evidence	Usual dose	US status
Mazdutide	Approved in China for chronic weight management and for glycemic control in type 2 diabetes. Not FDA-approved in the United States, where it is sold to consumers as a research-chemical vial.	Moderate human evidence	3-9 mg, once weekly, titrated upward from a lower starting dose	Research use only
Semaglutide	FDA-approved for type 2 diabetes in adults (Ozempic injection and tablets, Rybelsus), including cardiovascular risk reduction and, for the Ozempic injection, kidney-disease progression; and as Wegovy injection and tablets for chronic weight management and cardiovascular risk reduction in adults with obesity or overweight. The Wegovy injection is also approved for weight management from age 12 and for MASH with moderate to advanced liver fibrosis in adults.	Strong human evidence	FDA label	FDA-approved · prescription only
Tirzepatide	FDA-approved to improve glycemic control in type 2 diabetes in adults and children 10 years and older, and to reduce cardiovascular risk in adults with type 2 diabetes (Mounjaro), and for chronic weight management and moderate-to-severe obstructive sleep apnoea in adults with obesity (Zepbound).	Strong human evidence	FDA label	FDA-approved · prescription only
Liraglutide	FDA-approved as a once-daily injection under two brands: Saxenda, for chronic weight management alongside diet and exercise in adults and in children 12 years and older with obesity who weigh more than 60 kg, and Victoza, for glycemic control in type 2 diabetes in adults and children 10 years and older, and for reducing major adverse cardiovascular events in adults with type 2 diabetes and established cardiovascular disease.	Strong human evidence	FDA label	FDA-approved · prescription only
Orforglipron	FDA-approved as Foundayo, in combination with a reduced-calorie diet and increased physical activity, to reduce excess body weight and maintain weight reduction long term in adults with obesity, or adults with overweight who have at least one weight-related condition.	Strong human evidence	FDA label	FDA-approved · prescription only
Retatrutide	Investigational in Phase 3 trials for obesity, type 2 diabetes and related conditions. Not approved for any indication in the US. Sold outside the trial system as an unapproved research chemical, often alongside semaglutide and tirzepatide.	Moderate human evidence	2-12 mg, once weekly, starting at 2 mg and titrating up every 4 weeks to a 4-12 mg maintenance dose	Research use only
Survodutide	An investigational injectable peptide, not approved for any use. Its sponsor, Boehringer Ingelheim, is studying it in Phase 3 trials for chronic weight management and, in a separate programme, for MASH (metabolic dysfunction-associated steatohepatitis). It is also sold directly to consumers as a research chemical outside those trials.	Moderate human evidence	0.6-6 mg, once weekly, starting around 0.6 mg; the phase 2 trial titrated over about 20 weeks to a 2.4-4.8 mg maintenance dose, while the published phase 3 SYNCHRONIZE-1 trial randomizes to a higher 3.6 or 6.0 mg maintenance target using a slower, flexible up-titration	Research use only
Cagrilintide	Investigational amylin analogue studied alone and, more prominently, combined with semaglutide as the fixed-dose combination CagriSema, for chronic weight management. Not approved for any indication in the US; the combination is under FDA review following the sponsor's New Drug Application.	Moderate human evidence	0.25-4.5 mg, once weekly, titrating from a 0.25-0.6 mg starting dose up to a 2.4-4.5 mg maintenance dose	Research use only

Where to buy Mazdutide for research

Each vendor is checked against my vendor checklist.

I don't list a vendor for Mazdutide yet. Before buying from anyone, work through the vendor checklist.

See all vendors and how they compare →

Common questions

What is the usual mazdutide dose?

No dose is FDA-approved, because there is no FDA-approved product. China's phase 3 trials tested 4 mg and 6 mg weekly for weight management (GLORY-1) and 9 mg weekly in moderate-to-severe obesity (GLORY-2). Research-market sources describe a wider 3-9 mg weekly range, stepped up gradually. That is common practice, not a dose any US regulator set; the dosing page has the sourcing.

What are the side effects of mazdutide?

In its phase 2 and phase 3 trials, the most common side effects were nausea, vomiting and diarrhoea. They were generally more frequent at higher doses, as with other GLP-1 drugs. Full detail is on the dosing page.

Is mazdutide the same as semaglutide or tirzepatide?

No. All three act on the GLP-1 receptor. Semaglutide acts on GLP-1 alone, tirzepatide adds the GIP receptor, and mazdutide adds the glucagon receptor instead. They come from three companies, each with its own trials and regulatory status. My [GLP-1 peptides overview](/glp-1-peptides/) compares the class.

What is the difference between mazdutide and tirzepatide?

Both are once-weekly injections that act on the GLP-1 receptor. Tirzepatide adds the GIP receptor; mazdutide adds the glucagon receptor. Tirzepatide is FDA-approved (as Zepbound, for example), while mazdutide is approved only in China and reaches US buyers only as a research chemical. None of the trials cited here compares the two directly.

What is mazdutide peptide used for?

China's NMPA has approved it for two uses in adults: chronic weight management and blood-sugar control in type 2 diabetes. It has no approved use in the US, where it is sold only as a research chemical. Any dosing there is common practice, not set by a trial or a prescriber.

Is mazdutide better than retatrutide or other similar drugs?

I can't say, and I don't rank them. The trials cited here compared it with placebo and, in type 2 diabetes, with dulaglutide, which it beat on HbA1c lowering. A head-to-head trial against semaglutide (DREAMS-3) has published only its design so far, and I found no trial against retatrutide or tirzepatide. Retatrutide is still investigational; mazdutide is approved only in China.

References (4 sources)

Bibliographic detail is fetched from PubMed, not written by me - so a citation here cannot drift from the paper it names. Study design comes from PubMed's own tags rather than my judgement.

1.Hsia SH, Bays HE, Billings LK et al. Efficacy and safety of mazdutide in adults with obesity or overweight: a US-based, multicentre, phase 2, randomised, placebo-controlled clinical trial. Lancet Diabetes Endocrinol. 2026.StudyPMID 42628555
2.Guo L, Zhang B, Xue X et al. Mazdutide versus dulaglutide in Chinese adults with type 2 diabetes. Nature. 2026;652(8108):181-188.Randomised trialPMID 41407860
3.Innovent Announces Mazdutide, First Dual GCG/GLP-1 Receptor Agonist, Received Approval from China's NMPA for Chronic Weight Management- PR Newswire / Innovent Biologicsother
4.Innovent Announces Mazdutide Received Approval from China's NMPA for Glycemic Control in Adults with Type 2 Diabetes- PR Newswire / Innovent Biologicsother