Mazdutide: What to Know About the GLP-1 Drug Approved in China but Not the US

Mazdutide occupies an odd place in the GLP-1 world. It is not experimental. It is not a rumor. It is a fully approved, commercially marketed prescription weight-loss drug that hundreds of thousands of people have taken.

It is just approved in the wrong country, if you happen to be American.

That gap between “approved somewhere” and “approved here” is why mazdutide is one of the most searched and most misunderstood names in this class, and why it is a favorite of online sellers. This explains what mazdutide is, what its trials found, why it is not available in the United States, and what the real risk is with the version being sold online.

What is mazdutide?

Mazdutide, known in development as IBI362 in China and LY3305677 at Eli Lilly, is a once-weekly injection that activates two receptors: GLP-1 and glucagon [1].

It is based on oxyntomodulin, a naturally occurring hormone your gut releases after eating that happens to act on both receptors at once. Rather than engineering a molecule from scratch, mazdutide’s designers took what the body already makes and made it last longer.

Where it sits in the class:

• Semaglutide (Ozempic, Wegovy, Rybelsus): GLP-1
• Tirzepatide (Mounjaro, Zepbound): GIP + GLP-1
• Mazdutide: glucagon + GLP-1
• Survodutide (investigational): glucagon + GLP-1
• Retatrutide (investigational): GIP + GLP-1 + glucagon

Mazdutide’s claim to a footnote in history is that it was the first GLP-1 and glucagon dual agonist approved anywhere in the world. That makes it the real-world proof that the glucagon mechanism can work in people, which matters for every other glucagon-containing drug in development, including survodutide and retatrutide.

Who actually owns mazdutide?

This is the part that trips people up.

Eli Lilly originated the molecule. Innovent Biologics, a Chinese company, licensed it for greater China, ran the Chinese trials, obtained the Chinese approvals, and markets it there [1][2].

Lilly retains the rights outside China.

So the same company that makes Zepbound owns the US rights to mazdutide and has chosen not to bring it forward. That is not neglect. It is a portfolio decision. Lilly already has tirzepatide on the market, orforglipron approved as a pill, and retatrutide heading toward a filing in the first quarter of 2027 with the largest weight-loss numbers ever reported in a pivotal trial. Adding a fourth obesity product that performs below retatrutide, requires its own multi-year Phase 3 program, and would compete with its own drugs is a hard case to make internally.

Lilly has not ignored the molecule entirely. The registry shows a completed ex-China Phase 2 obesity study (NCT06124807, 179 participants, completed January 2025), a Phase 2 study in alcohol use disorder (NCT06817356, 308 participants, completed March 2026), and mazdutide appendices inside a broader Lilly obesity master protocol (NCT06143956) [3][4][8]. What the registry does not show is a US Phase 3 registrational obesity program. Without one, there is no path to a US approval.

What did the mazdutide trials show?

The Chinese Phase 3 program is called GLORY.

GLORY-2, reported in November 2025, tested the 9 mg dose in Chinese adults with obesity over 60 weeks. Result: up to 20.1% average weight loss, meeting the primary endpoint and all key secondary endpoints [1].

A separate Chinese Phase 3 compared mazdutide head to head against semaglutide in adults with early type 2 diabetes and obesity (NCT06184568, 349 participants, completed September 2025), reporting better results on both glycemic and weight endpoints [5].

Head-to-head data are rare and valuable, so that result deserves attention. It also deserves two important qualifications.

First, population. These trials enrolled Chinese adults. Average starting BMI in Chinese obesity trials is typically lower than in US trials, because China’s obesity thresholds are set lower (a BMI of 28 rather than 30). Percentage weight loss does not always translate cleanly between populations with different starting points, body compositions and diets. This is a genuine scientific limitation, not a dismissal.

Second, dose. The comparison used specific doses of each drug. A different semaglutide dose, or the newer 7.2 mg Wegovy HD dose approved in the United States in March 2026, would change the comparison.

Innovent has kept expanding the program. Active Chinese trials include adolescents with obesity (NCT07255209), obstructive sleep apnea (NCT06931028), heart failure with preserved or mildly reduced ejection fraction, MASH, hypertension, and a comparison against semaglutide in fatty liver disease [6][7]. There are also dozens of investigator-initiated Chinese studies in everything from PCOS to post-bariatric-surgery care.

Why can’t Americans get mazdutide?

Because the FDA has not approved it, and no one has asked the FDA to.

This is worth stating plainly, because there is a persistent belief that a drug approved in a major market is somehow “pre-cleared” elsewhere. It is not. Each regulator reviews its own application, on its own data package, against its own standards. China’s National Medical Products Administration approved mazdutide on Innovent’s Chinese trial data. The FDA has never reviewed mazdutide, because no application has been submitted.

There is also no reciprocal-approval mechanism. The FDA does not accept an NMPA approval, an EMA approval, or any other regulator’s approval as a substitute for its own review. A US approval would require a US application, which would almost certainly require trials including US participants.

And there is no importation route for personal use here. FDA policy allows very limited personal importation in narrow circumstances, generally involving serious conditions with no US treatment available. Obesity has multiple FDA-approved treatments in the United States, so that exception does not apply.

What about mazdutide sold online?

This is where mazdutide becomes genuinely dangerous, and it is dangerous in a specific way that is different from other pipeline drugs.

With a drug like retatrutide or VK2735, which are not approved anywhere, everyone understands that online vials are unapproved. With mazdutide, sellers can point at a real approval in a real country and a real product in real pharmacies, and say “this is an approved medicine.”

That framing is false in the way that matters. The mazdutide sold to US buyers online is not the Innovent product dispensed in Chinese pharmacies. Innovent’s approved product moves through a regulated Chinese distribution chain into Chinese pharmacies, under Chinese prescription requirements. It does not get shipped to American consumers by unregistered websites.

What those websites sell is peptide synthesized by unregulated manufacturers, frequently labeled “research use only” or “not for human consumption.” There is no verification that it is the correct molecule, no verification of purity, no sterility testing, and no confirmation that the stated dose matches the contents. Reconstitution instructions from a seller are not a label, and a certificate of analysis provided by the seller is not independent testing.

The FDA has issued warnings about unapproved GLP-1 products sold for weight loss, including reports of dosing errors and adverse events [9]. Those warnings apply to mazdutide exactly as they do to every other name in this market.

There is also a legal dimension. Distributing an unapproved new drug in the United States is unlawful, and importing one for personal use is generally not permitted outside the narrow exceptions above.

What are mazdutide’s side effects?

The Chinese trials reported the pattern typical of this class: nausea, diarrhea, vomiting and decreased appetite, concentrated during dose escalation.

Because mazdutide includes glucagon activity, there is additional interest in its effects on heart rate and on liver enzymes, which are the areas where glucagon-containing drugs are watched most closely. Detailed safety data live in the Chinese regulatory documentation and the trial publications rather than in an FDA label, since no FDA label exists.

That absence is its own point. When a drug is FDA approved, you get a standardized prescribing information document with a full adverse-reaction table, contraindications, warnings, drug interactions and pregnancy information, written to a US regulatory standard and available for free. For mazdutide, US patients and clinicians have no such document. That is one more reason self-treating with an online product is a poor idea: nobody has the reference material they would need to manage a problem.

Could mazdutide ever come to the United States?

It is possible, but nothing points that way today.

What would have to happen: Lilly would need to decide mazdutide has a role its existing portfolio does not fill, start a US Phase 3 program, run it for roughly two years, submit an application, and wait out a review. From a standing start, that is a five-plus-year path even if the decision were made tomorrow.

The likelier scenarios are that Lilly keeps mazdutide as a China-partnered asset generating royalties, or develops it for a niche indication where it has a distinct advantage. The alcohol use disorder trial is a hint that Lilly has been looking at non-obesity uses.

What mazdutide will almost certainly remain is a reference point. It is the drug that proved GLP-1 plus glucagon works in people at commercial scale, and it is the drug that showed a Chinese biotech could run a competitive head-to-head against semaglutide. Both of those facts shape how the rest of the field is developing, including drugs that will reach US patients.

The bottom line

Mazdutide is a legitimate, effective, approved medicine. It is just not a medicine that is available to you in the United States, and it will not be for a long time, if ever.

If you are searching for mazdutide because you want a glucagon-containing drug, the ones on a US path are survodutide, which is investigational with no announced filing date, and retatrutide, which Lilly plans to file in the first quarter of 2027. Neither is available yet either, but at least they are pointed at a US approval.

If you are searching because you found a website selling it, the honest answer is that the website is not selling you the drug in this article.

Talk to a healthcare provider about the options that actually exist for you now.

Sources

1. Innovent Biologics, “Mazdutide 9 mg achieves up to 20.1% weight loss in Chinese adults with obesity: GLORY-2 study meets primary and all key secondary endpoints” — https://www.prnewswire.com/news-releases/mazdutide-9-mg-achieves-up-to-20-1-weight-loss-in-chinese-adults-with-obesity-glory-2-study-meets-primary-and-all-key-secondary-endpoints-302620471.html
2. Innovent Biologics, “Innovent announces mazdutide received approval from China’s NMPA for glycemic control in adults with type 2 diabetes” — https://www.prnewswire.com/news-releases/innovent-announces-mazdutide-received-approval-from-chinas-nmpa-for-glycemic-control-in-adults-with-type-2-diabetes-302561434.html
3. ClinicalTrials.gov, NCT06124807 (LY3305677 Phase 2, Eli Lilly) — https://clinicaltrials.gov/study/NCT06124807
4. ClinicalTrials.gov, NCT06143956 (LY900038 obesity master protocol) — https://clinicaltrials.gov/study/NCT06143956
5. ClinicalTrials.gov, NCT06184568 (IBI362 versus semaglutide) — https://clinicaltrials.gov/study/NCT06184568
6. ClinicalTrials.gov, NCT07255209 (IBI362 in Chinese adolescents) — https://clinicaltrials.gov/study/NCT07255209
7. ClinicalTrials.gov, NCT06931028 (IBI362 in obstructive sleep apnea) — https://clinicaltrials.gov/study/NCT06931028
8. ClinicalTrials.gov, NCT06817356 (mazdutide in alcohol use disorder, Eli Lilly) — https://clinicaltrials.gov/study/NCT06817356
9. FDA, concerns about unapproved GLP-1 drugs used for weight loss — https://www.fda.gov/drugs/drug-alerts-and-statements/fdas-concerns-unapproved-glp-1-drugs-used-weight-loss