Peptide education
Mazdutide
IBI362 · LY3305677 · Xinermei
Mazdutide is a peptide that activates GLP-1 and glucagon receptors. It has been studied as a once-weekly injection for weight management and type 2 diabetes. Its approval depends on the country and the particular use.
Chinese phase 3 studies report weight and blood-sugar benefits in defined populations. Mainland China has approved specified uses, while no FDA-approved product was found in the U.S. drug database.
Overview
Quick answer
Mainland China has approved mazdutide injection for specified adult weight and diabetes uses. Macao has separate authorizations. Neither decision establishes U.S. FDA approval or verifies a separately sourced product.
What is mazdutide approved for in mainland China?
The Chinese regulator lists approvals for mazdutide injection. Its manufacturer reports approved adult indications for long-term weight management and blood-sugar control in type 2 diabetes. The weight indication applies alongside diet and physical activity to adults with an initial BMI of at least 28, or at least 24 with a weight-related condition.
Is mazdutide authorized in Macao?
Macao's regulator lists mazdutide injection for specified adult weight-management use. The manufacturer also reports a separate Macao authorization for adult type 2 diabetes. The local prescribing label should be checked for the applicable details.
Is mazdutide FDA-approved?
No FDA-approved mazdutide product was found in the U.S. drug database. A U.S. phase 2 study has been published, but a trial does not confer approval.
What did GLORY-1 show?
In Chinese adults with overweight or obesity without diabetes, the 4 mg and 6 mg weekly study groups lost more weight than the placebo group at the primary 32-week assessment and at week 48.
Does the 9 mg trial describe the same population?
Not exactly. GLORY-2 enrolled Chinese adults with obesity, including some with type 2 diabetes, and compared a 9 mg weekly target with placebo for 60 weeks. GLORY-1 excluded diabetes.
Has it been compared directly with semaglutide?
Yes. An open-label trial in Chinese adults with early type 2 diabetes and obesity compared mazdutide 6 mg with semaglutide 1 mg. A conference abstract reports a better combined blood-sugar and weight endpoint for mazdutide in that comparison. Nausea and vomiting were more frequent with mazdutide at those doses. The result does not establish superiority for every dose, population, or indication.
Evidence
Evidence snapshot
The 610-person study excluded diabetes. Its primary weight endpoints were assessed at week 32, with additional results at week 48.
The 60-week study included adults with obesity, some of whom had type 2 diabetes. Gastrointestinal events were common in the active group.
DREAMS-2 compared mazdutide with a specific dose of dulaglutide in Chinese adults receiving background oral diabetes treatment.
DREAMS-3 compared specific weekly doses in an open-label diabetes and obesity trial. The available source is a conference abstract, not a full trial report.
Mainland China and Macao have separate regulatory decisions. A U.S. FDA drug database search found no approved mazdutide product.
A 179-person trial studied doses up to 16 mg in adults without type 2 diabetes. At 16 mg, 20% discontinued because of adverse events.
Claims
Common claims vs evidence
| Claim | Human evidence | Mechanistic evidence | Verdict |
|---|---|---|---|
| Mazdutide is an FDA-approved weight-loss medicine. | The FDA drug database search found no approved mazdutide product. China has approved a mazdutide injection for specific adult uses. | No. China's authorization and U.S. FDA approval are separate decisions. | |
| Mazdutide reduced weight versus placebo in phase 3 studies. | GLORY-1 studied 4 mg and 6 mg in Chinese adults without diabetes. GLORY-2 studied a 9 mg target in Chinese adults with obesity, including some with diabetes. Both reported greater average weight reductions than placebo at their stated assessment times. | GLP-1 and glucagon receptor activity is the proposed biological rationale, while the controlled outcomes measure what happened in trials. | Supported in these studied populations and schedules, not a guarantee of an individual response. |
| Mazdutide has never been compared with semaglutide. | A conference abstract reports an open-label trial comparing mazdutide 6 mg and semaglutide 1 mg in Chinese adults with early type 2 diabetes and obesity. Nausea and vomiting were more frequent with mazdutide in this comparison. | Incorrect. The comparison exists, but its population, doses, endpoint, open-label design, and conference-report format limit broader conclusions. | |
| A China-approved injection makes any online mazdutide product equivalent. | FDA identified a named U.S. seller's mazdutide product as an unapproved new drug. The regulator's letter concerns that seller's products. | No. Authorization of a specific product does not establish the identity, sterility, storage, or legal status of another product. |
Bottom line
Main takeaway
Mazdutide has approved adult uses in China but was not found as an FDA-approved product in the United States.
The main weight trials had different entry criteria and dose targets. GLORY-1 excluded diabetes, whereas GLORY-2 included some people with it.
DREAMS-2 is a published comparison with dulaglutide 1.5 mg. DREAMS-3 has a conference report comparing mazdutide 6 mg with semaglutide 1 mg.
Identity
What it is
Mazdutide is one peptide with activity at both GLP-1 and glucagon receptors. Trial participants received it by subcutaneous injection. It is not tirzepatide, which has a different second receptor target.
China's product approval is a specific regulatory decision. The U.S. phase 2 research record and FDA database search answer different questions about development and U.S. approval.
Use context
Routes, doses, and cycle patterns
The GLORY and DREAMS studies used different doses and enrolled different groups. Approved prescribing information depends on the country and use.
Human studies and product labels
GLORY-1
- Purpose
- Weight management in adults without diabetes
- Context
- Randomized phase 3 trial in China
- Route
- Subcutaneous
- Amount
- 4 mg or 6 mg target-dose groups, after escalation
- Frequency
- Once weekly
- Duration
- 48 weeks, with primary assessment at week 32
The trial included placebo and used a treatment-policy analysis for its primary outcomes. Both active groups started at 2 mg for four weeks, then 4 mg; the 6 mg group increased again after four weeks.
GLORY-2
- Purpose
- Weight reduction in adults with obesity
- Context
- Randomized phase 3 trial in China, with and without type 2 diabetes
- Route
- Subcutaneous
- Amount
- Started at 3 mg, then increased to 6 mg and 9 mg at four-week intervals
- Frequency
- Once weekly
- Duration
- 60 weeks
The study included participants with and without type 2 diabetes. The listed schedule is a trial regimen. Its result does not establish whether 9 mg is an approved dose.
DREAMS-2
- Purpose
- Glycemic control in adults with type 2 diabetes
- Context
- Randomized phase 3 active-comparator trial in China
- Route
- Subcutaneous
- Amount
- Mazdutide 4 mg or 6 mg versus dulaglutide 1.5 mg
- Frequency
- Once weekly
- Duration
- 28 weeks for the reported comparison
Participants were also receiving background oral diabetes drugs. The comparator and study doses matter when interpreting the HbA1c result.
U.S. phase 2 weight study
- Purpose
- Weight-management research without type 2 diabetes
- Context
- Randomized phase 2 trial in the United States
- Route
- Subcutaneous
- Amount
- Escalated to 3 mg then 6 mg, 10 mg, or 16 mg in separate groups
- Frequency
- Once weekly
- Duration
- 48 weeks, with primary assessment at week 32
The 3 mg group remained at that dose through week 32 before escalating to 6 mg. These study regimens are not U.S.-approved doses.
Mainland China weight-management label
- Purpose
- Labeled weight-management use
- Context
- Xinermei product label for eligible adults in mainland China
- Route
- Subcutaneous
- Amount
- 2 mg starting dose, followed by 4 mg and, if appropriate, 6 mg maintenance
- Frequency
- Once weekly, with at least four weeks at each escalation step
The cited weight-management label describes its own dosing and contraindications. It is not a U.S. label or a recommendation for an individual; the applicable local product information should be checked.
What varies
- Population: GLORY-1 excluded diabetes; GLORY-2 included some participants with it.
- Assessment: GLORY-1's primary weight endpoints were at week 32, not week 48.
- Jurisdiction: China's approved indications do not establish FDA approval.
Research
Research evidence
GLORY-1 and GLORY-2 found lower average body weight with weekly mazdutide than placebo in different Chinese adult populations. A published U.S. phase 2 study used different dose targets. DREAMS-2 provides a published active comparison in type 2 diabetes; DREAMS-3 is a conference-reported, open-label comparison against a specific semaglutide dose.
| Study / evidence area | Population | Design | Product context | Main outcome | Limitations | Weight |
|---|---|---|---|---|---|---|
| GLORY-1 | 610 Chinese adults with overweight or obesity, without diabetes | Randomized, double-blind, placebo-controlled phase 3 trial | Weekly injections with 4 mg or 6 mg target doses | At week 32, mean weight changes were minus 10.09% with 4 mg, minus 12.55% with 6 mg, and plus 0.45% with placebo. At week 48 they were minus 11.00%, minus 14.01%, and plus 0.30%, respectively. | Conducted in China under specific BMI criteria; not a direct comparison with another active weight-management drug. | Controlled phase 3 human evidence |
| GLORY-2 | 461 analyzed Chinese adults with obesity, 16.1% with type 2 diabetes | Randomized, double-blind, placebo-controlled phase 3 trial | Weekly injection with a 9 mg target dose | At week 60, mean weight change was minus 16.65% with mazdutide versus minus 1.50% with placebo. | The study used a higher target and different eligibility criteria from GLORY-1. Its 9 mg result is not an approved-dose statement. | Controlled phase 3 human evidence |
| DREAMS-2 | 731 Chinese adults with type 2 diabetes on background oral diabetes drugs | Randomized, active-comparator phase 3 trial | Mazdutide 4 mg or 6 mg versus dulaglutide 1.5 mg weekly | At week 28, mean HbA1c reduction favored the 4 mg and 6 mg mazdutide groups over the comparator by 0.24 and 0.30 percentage points. | The comparison is specific to the studied population and dulaglutide dose. | Published active-comparator phase 3 trial |
| DREAMS-3 | 349 Chinese adults with early type 2 diabetes and obesity | Randomized, open-label phase 3 trial, conference abstract | Mazdutide 6 mg versus semaglutide 1 mg weekly | The conference report describes a higher proportion meeting its combined HbA1c and weight-loss endpoint with mazdutide at week 32. | Open-label design and conference abstract; it does not compare all semaglutide doses or establish results in people without diabetes. | Conference-reported direct comparison |
| U.S. phase 2 weight study | 179 U.S. adults with obesity or qualifying overweight, without type 2 diabetes | Randomized, double-blind, placebo-controlled phase 2 trial | Weekly injections with 3 to 6 mg, 10 mg, or 16 mg study regimens | At week 32, estimated mean weight change was minus 7.3%, minus 15.6%, and minus 18.1% in the 3 to 6 mg, 10 mg, and 16 mg groups versus minus 0.9% with placebo, using the efficacy estimand. The 3 to 6 mg group remained at 3 mg until its scheduled escalation at week 32. | The primary estimand was hypothetical. The 16 mg group had the highest adverse-event discontinuation rate; the study doses are not FDA-approved. | Published controlled phase 2 human evidence |
Cautions
Safety and unknowns
- The mainland Chinese weight-management label warns that mazdutide caused thyroid C-cell tumors in rodents; whether this occurs in humans is unknown. That label contraindicates use in people with a personal or family history of medullary thyroid carcinoma or with multiple endocrine neoplasia syndrome type 2 (MEN2). This is label information for that product, not a determination about an individual's care.
- In GLORY-2, vomiting occurred in 53.1% of the mazdutide group versus 1.3% of the placebo group; nausea occurred in 46.9% versus 3.2%; and diarrhea in 39.4% versus 6.5%. Most reported events were mild or moderate, and adverse events led to treatment discontinuation in 2.9% versus 0%.
- In GLORY-1, gastrointestinal events were most frequent and mostly mild or moderate. Adverse events led to discontinuation in 1.5% of the 4 mg group, 0.5% of the 6 mg group, and 1.0% of the placebo group.
- In the DREAMS-3 conference abstract, nausea occurred in 30.5% with mazdutide 6 mg versus 12.6% with semaglutide 1 mg; vomiting occurred in 23.6% versus 8.6%. The study was open-label and enrolled Chinese adults with type 2 diabetes and obesity.
- In the U.S. phase 2 study, 20% of participants in the 16 mg group discontinued treatment because of adverse events, primarily gastrointestinal disorders. This was a separate study and dose from the Chinese phase 3 trials.
- The published trials do not settle every rare adverse effect or the long-term risk for people outside their enrollment criteria. An individual product's local prescribing information remains the authority for its warnings and approved use.
Product quality
Product identity and quality
An approved product in China is not the same as an independently sourced vial merely labeled mazdutide. Identity, concentration, sterility, and storage are product-specific questions.
FDA identified a named seller's mazdutide product as an unapproved new drug. That enforcement action does not characterize every seller or every product batch.
Jurisdiction and product
Approval attaches to a product and its authorized uses in a jurisdiction, not to any vial carrying the ingredient name.
Identity and handling
Trial efficacy does not verify a different product's identity, concentration, sterility, or storage conditions.
Mechanism
How it is proposed to work
Mazdutide activates GLP-1 and glucagon receptors. Researchers study whether this combination can affect weight and glucose regulation.
The additional glucagon receptor target distinguishes mazdutide from medicines that act only at GLP-1 receptors. It does not by itself prove that mazdutide is better for a particular patient.
Direct comparisons are most useful when their population, dose, endpoint, and follow-up are kept intact. The DREAMS-3 conference report compares two particular doses, not every possible treatment.
FAQ
Common questions
Is mazdutide approved?
Mainland China has approved mazdutide injection for specified adult uses. Macao's regulator separately lists a weight-management authorization, and the manufacturer reports a diabetes authorization. No FDA-approved mazdutide product was found in the U.S. drug database; authorization elsewhere requires a jurisdiction-specific check.
Has mazdutide been compared with semaglutide?
Yes. An open-label phase 3 study in Chinese adults with diabetes and obesity compared mazdutide 6 mg with semaglutide 1 mg. A conference abstract reports a favorable combined endpoint and more nausea and vomiting with mazdutide in that particular comparison, not all uses or doses.
Details
Technical details
Sources
References
- 1.
PubMed. Once-Weekly Mazdutide in Chinese Adults with Obesity or Overweight
doi:10.1056/NEJMoa2411528 PMID:40421736 NCT05607680
Peer-reviewed randomized phase 3 trial in Chinese adults; primary outcomes were assessed at week 32.
- 2.
ClinicalTrials.gov. GLORY-1 trial registration
NCT05607680
Trial eligibility excluded diabetes and the registry describes titration and study arms.
- 3.
doi:10.1001/jama.2026.8142 PMID:42251595 NCT06164873
Peer-reviewed 60-week phase 3 trial of a 9 mg target dose; 16.1% of analyzed participants had type 2 diabetes.
- 4.
PubMed. Mazdutide versus dulaglutide in Chinese adults with type 2 diabetes
doi:10.1038/s41586-025-10031-z PMID:41407860
Published phase 3 active-comparator diabetes trial in Chinese adults receiving background oral diabetes drugs.
- 5.
American Diabetes Association. Mazdutide vs. Semaglutide in Chinese Adults with Type 2 Diabetes and Obesity (DREAMS-3)
doi:10.2337/db26-1226-OR NCT06184568
Conference abstract reporting an open-label phase 3 comparison of mazdutide 6 mg with semaglutide 1 mg; not a full trial report.
- 6.
ClinicalTrials.gov. A Study of LY3305677 Compared With Placebo in Adult Participants With Obesity or Overweight
NCT06124807
U.S. phase 2 trial registry reports completion and posted results; it is not an approval.
- 7.
PubMed. Efficacy and safety of mazdutide in adults with obesity or overweight: a US-based phase 2 trial
doi:10.1016/S2213-8587(26)00160-9 PMID:42628555 NCT06124807
Published U.S. phase 2 trial, including a 16 mg group and adverse-event discontinuations.
- 8.
China National Medical Products Administration. NMPA drug approval document delivery information for mazdutide injection
Chinese regulator lists three mazdutide injection approvals. The listing itself does not specify the indications.
- 9.
Innovent Biologics. Innovent mazdutide clinical update and China indication summary
Manufacturer reports China-approved adult weight-management and type 2 diabetes indications; cited alongside the NMPA product listing.
- 10.
Suzhou Municipal Government. Suzhou government update on mazdutide diabetes and weight-management studies
Government report states that mazdutide has China approvals for diabetes and weight reduction; it is not the prescribing label.
- 11.
Innovent Biologics. Xinermei mazdutide injection prescribing information for weight management
Chinese weight-management product label with thyroid C-cell tumor warning and contraindications; not the separate diabetes label.
- 12.
Macao Pharmaceutical Administration Bureau. Macao Pharmaceutical Administration Bureau list of approved new medicines
Regulator list includes mazdutide injection for specified adult weight-management use.
- 13.
Innovent Biologics. Innovent annual report describing Macao mazdutide approvals
Manufacturer reports that Macao authorized mazdutide for adult type 2 diabetes; this is not the Macao prescribing label.
- 14.
FDA. Drugs@FDA: FDA-approved drugs database
A Drugs@FDA API active-ingredient search returned no matches for mazdutide.
- 15.
FDA. NuScience Peptides LLC warning letter
FDA identifies a named seller's mazdutide product as an unapproved new drug; this finding is specific to the products in the letter.
- 16.
FDA. MOUNJARO prescribing information
The FDA label identifies tirzepatide as a GIP and GLP-1 receptor agonist, distinct from mazdutide's glucagon and GLP-1 targets.