No trial has compared mazdutide with tirzepatide; in separate Chinese trials, both beat placebo by about 15 percentage points of body weight. Both were tested in people, and only tirzepatide is FDA approved as of October 2026.
In trials of Chinese adults with obesity or overweight, the two drugs beat placebo by similar margins: 15.15 percentage points for mazdutide's highest dose at 60 weeks (GLORY‑2) and 15.1 for tirzepatide's highest dose at 52 weeks (SURMOUNT‑CN). No trial has given both drugs. Tirzepatide has far more evidence behind it: worldwide phase 3 trials, a liver biopsy trial, a heart failure outcomes trial and FDA approval. Mazdutide is approved only in China, and a 2026 BMJ review rated its weight evidence low to very low certainty.
Every claim on this page is labeled by what was tested: in people, in animals or cells, or a regulatory fact. How we grade evidence: editorial policy.
| Item | Mazdutide | Tirzepatide |
|---|---|---|
| What it is | Weekly injection that switches on two receptors: GLP-1 and glucagon | Weekly injection that switches on two receptors: GIP and GLP-1 |
| Made by | Innovent Biologics in China, under license from Eli Lilly | Eli Lilly (Mounjaro, Zepbound) |
| Evidence label | Tested in people: phase 3 trials, almost all in China | Tested in people: phase 3 trials worldwide |
| FDA status | Not approved; approved in China in 2025 | Approved: Mounjaro (2022) and Zepbound (2023) |
| WADA 2026 | Not named on the list | Not banned; tracked in the 2026 Monitoring Program |
| Last checked | October 18, 2026 | October 18, 2026 |
New trials, FDA changes and side-effect reports, written in plain English. Every result says whether it was tested in people or in animals.
Each row names its evidence type. Every study named here is linked in the sources list at the bottom of the page.
| Mazdutide | Tirzepatide | Evidence type | |
|---|---|---|---|
| Weight loss in Chinese adults | GLORY-1: 610 adults, 48 weeks. Weight fell 11.0% and 14.0% on the two doses vs a 0.3% gain on placebo | SURMOUNT-CN: 210 adults, 52 weeks. Weight fell 13.6% and 17.5% on the two doses vs 2.3% on placebo | Tested in people |
| Highest dose tested in China | GLORY-2: 462 adults, 60 weeks. Weight fell 16.7% vs 1.5% on placebo, a 15.15-point gap | SURMOUNT-CN top dose: a 15.1-point gap over placebo at 52 weeks | Tested in people |
| Largest trial outside China | US phase 2: 179 adults. At 32 weeks weight fell 7.3% to 18.1% across doses vs 0.9% on placebo, in people who stayed on treatment | SURMOUNT-1: 2,539 adults, 72 weeks. Weight fell 15.0%, 19.5% and 20.9% vs 3.1% on placebo | Tested in people |
| Blood sugar in type 2 diabetes | DREAMS-1: 320 adults, 24 weeks. HbA1c fell 1.57 and 2.15 points vs 0.14 on placebo | SURPASS-2: 1,879 adults, 40 weeks. HbA1c fell 2.01 to 2.30 points vs 1.86 on semaglutide | Tested in people |
| Against an approved drug | Beat dulaglutide on HbA1c and weight in a 731-person diabetes trial (DREAMS-2). A trial against semaglutide finished; no results in a journal yet | Beat semaglutide on weight in a 751-person obesity trial (SURMOUNT-5): 20.2% vs 13.7% at 72 weeks | Tested in people |
| Fatty liver | No published biopsy trial. A phase 2 trial in MASH is recruiting | SYNERGY-NASH: 190 adults with MASH and scarring. Inflammation cleared without worse scarring in 44% to 62% vs 10% on placebo at 52 weeks | Tested in people |
| Heart outcomes | No outcome results. A 141-person phase 2 trial in heart failure with obesity is under way | SUMMIT: 731 adults with heart failure and obesity. Heart death or worsening heart failure in 9.9% vs 15.3% on placebo | Tested in people |
| Stomach side effects | GLORY-2: vomiting 53.1%, nausea 46.9%, diarrhea 39.4% vs 1.3%, 3.2% and 6.5% on placebo | SURMOUNT-CN: diarrhea about 40%, nausea 30% to 32%, vomiting 11% to 20% vs 8.7%, 5.8% and 4.3% on placebo | Tested in people |
| Certainty of the weight evidence | Very low to low, in a 2026 BMJ review of 262 obesity drug trials | Moderate to high, in the same 2026 BMJ review | Tested in people |
| Approval, October 2026 | China only (weight management June 2025, type 2 diabetes September 2025). Not approved by FDA | FDA approved for type 2 diabetes (2022) and weight management (2023); approved in China in 2024 | Regulatory fact |
Both switch on the GLP-1 receptor. Mazdutide's second target is the glucagon receptor; tirzepatide's is the GIP receptor. Both are weekly injections.
Mazdutide is a GLP-1 and glucagon receptor dual agonist. Eli Lilly discovered it and licensed it to Innovent Biologics for China, where Innovent ran the GLORY and DREAMS trials. Lilly ran its own phase 2 trial of 179 adults in the US (tested in people).
Tirzepatide is a GIP and GLP-1 receptor dual agonist made by Eli Lilly. FDA approved it as Mounjaro for type 2 diabetes in May 2022 and as Zepbound for weight management in November 2023 (regulatory fact).
In Chinese adults the two beat placebo by about the same margin, around 15 percentage points at their highest doses. No trial has given both drugs, so neither has been shown to beat the other.
In GLORY-2, 462 Chinese adults with obesity lost 16.7% of their weight over 60 weeks on mazdutide's highest dose, against 1.5% on placebo, a gap of 15.15 points (Gao, 2026). In SURMOUNT-CN, 210 Chinese adults with obesity or overweight lost 17.5% over 52 weeks on tirzepatide's highest dose, against 2.3% on placebo, a gap of 15.1 points (Zhao, 2024). Both trials were placebo-controlled (tested in people).
At the two doses tested in GLORY-1, mazdutide cut weight 11.0% and 14.0% over 48 weeks in 610 Chinese adults, while placebo gained 0.3% (Ji, 2025). Outside China, tirzepatide's SURMOUNT-1 trial of 2,539 adults found 20.9% weight loss at 72 weeks on the highest dose against 3.1% on placebo (Jastreboff, 2022). Mazdutide's largest trial outside China is a 179-person US phase 2, where weight fell up to 18.1% at 32 weeks among people who stayed on treatment, and 20% of people on the highest dose stopped because of side effects (Hsia, 2026).
These are separate trials with different lengths, entry criteria and analysis methods. A 2026 BMJ network meta-analysis of 262 trials estimated tirzepatide's one-year weight loss at 14.9% more than lifestyle change alone with moderate to high certainty, and put mazdutide in a group of newer drugs at 13.1% to 14.6% with low to very low certainty (Nong, 2026).
Patients. Tested in people. Every trial shown had a placebo group or an approved drug as the comparison. Mazdutide's DREAMS-3 trial against semaglutide (349 people) is left out because its results are not in a journal yet.
Tirzepatide. Both lower blood sugar in type 2 diabetes, but only tirzepatide has a liver biopsy trial and a heart failure outcomes trial.
Type 2 diabetes: in DREAMS-1, 320 Chinese adults had HbA1c drop 1.57 and 2.15 points over 24 weeks on mazdutide, against 0.14 on placebo (Zhu, 2026). In DREAMS-2, 731 adults did better on mazdutide than on dulaglutide, by 0.24 to 0.30 HbA1c points and 3.8 to 5.8 points of weight (Guo, 2026). In SURPASS-2, 1,879 adults had HbA1c drop 2.01 to 2.30 points over 40 weeks on tirzepatide, against 1.86 on semaglutide (Frías, 2021). All tested in people.
Fatty liver: in SYNERGY-NASH, 190 adults with MASH (fatty liver with inflammation) and moderate or severe scarring were treated for 52 weeks; the inflammation cleared without worse scarring in 44% to 62% on tirzepatide, against 10% on placebo (Loomba, 2024; tested in people). Mazdutide has no published biopsy trial. Innovent's phase 2 MASH trial is recruiting, and a 479-person trial against semaglutide in fatty liver is under way.
Heart: in SUMMIT, 731 adults with heart failure with preserved ejection fraction and obesity, death from heart causes or worsening heart failure occurred in 9.9% on tirzepatide against 15.3% on placebo (Packer, 2025; tested in people). Mazdutide's 141-person phase 2 trial in heart failure with preserved or mildly reduced ejection fraction and obesity is under way, with no results posted.
Both mostly cause nausea, vomiting and diarrhea, usually mild to moderate. Vomiting was more common in mazdutide's highest-dose trial than in tirzepatide's Chinese trial.
Mazdutide: in GLORY-2, vomiting affected 53.1%, nausea 46.9% and diarrhea 39.4%, against 1.3%, 3.2% and 6.5% on placebo; 2.9% stopped because of side effects, against none on placebo. At the two lower doses in GLORY-1, 1.5% and 0.5% stopped for side effects, against 1.0% on placebo (tested in people).
Tirzepatide: in SURMOUNT-CN, diarrhea affected 40.0% and 40.8% on the two doses, nausea 30.0% and 32.4%, and vomiting 11.4% and 19.7%, against 8.7%, 5.8% and 4.3% on placebo. In SURMOUNT-1, 4.3% to 7.1% stopped for side effects, against 2.6% on placebo (tested in people).
No. As of October 2026 mazdutide is approved only in China, and Lilly has not registered a phase 3 trial of it on ClinicalTrials.gov. Tirzepatide is FDA approved.
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