Mazdutide is an experimental medicine that copies two of the body's hormones at once — GLP-1 and glucagon — much like survodutide. What makes it distinct is its origin story and its trials: it is developed by China's Innovent Biologics (under a licence from Eli Lilly) and its landmark phase-3 results come from large trials in Chinese adults. It is still investigational.
In plain terms: another two-target weight drug — this one with its strongest data from China-led phase-3 trials.
(The figure illustrates the dual-agonist concept. Mazdutide's exact pair is glucagon + GLP-1, not the GIP + GLP-1 pair shown.)
What it is
Mazdutide (research code IBI362, sometimes LY3305677) is a peptide — a short chain of amino acids. It is built from oxyntomodulin, a natural gut hormone your body already makes after eating that, unusually, switches on *both* the GLP-1 and glucagon receptors on its own1. Mazdutide is a longer-lasting, engineered version of that natural dual action.
The two receptors it activates:
- GLP-1 (glucagon-like peptide-1) — curbs appetite and helps release insulin.
- Glucagon — thought to raise energy expenditure (calories burned) and to help clear fat from the liver.
Because it hits two receptors, it is a dual agonist — an "agonist" being a molecule that switches a receptor on.
The mechanism: appetite plus energy-burning
The design logic mirrors other GLP-1 / glucagon drugs: use two levers instead of one.
- The GLP-1 lever lowers appetite and slows stomach emptying, so meals feel more filling.
- The glucagon lever is meant to raise the body's energy expenditure and mobilise stored fat.
In plain terms: eat less (GLP-1) and burn a bit more (glucagon). Building it from oxyntomodulin means the molecule keeps the natural balance between the two signals.
Pharmacokinetics: why once a week
Mazdutide is engineered for once-weekly injection. Its reported half-life — the time for half a dose to clear — is around 8 days, long enough to hold steady levels between weekly doses. Like other drugs in this family, it uses a fatty-acid tail that binds albumin (a blood protein) to slow its breakdown.
| Property | Mazdutide (reported) |
|---|---|
| Receptor targets | GLP-1 + glucagon (dual agonist) |
| Molecular basis | Oxyntomodulin analogue |
| Route studied | Subcutaneous (under the skin) |
| Reported half-life | ~8 days |
| Dosing rhythm studied | Once weekly |
| Approval status (2026) | Investigational (phase 3; review in China) |
What the trials actually found
Mazdutide's headline evidence is its phase-3 GLORY program. Phase 3 means a large, late-stage trial — the kind that supports approval. The important caveat: these trials studied Chinese adults, so the numbers may not transfer exactly to other populations. Note the model in each row.
| Trial | People | Key result | Year |
|---|---|---|---|
| Ji et al. — GLORY-1 (phase 3)1 | 610 Chinese adults with overweight/obesity | On 6 mg, ~14% body-weight loss at 48 weeks; ~50% lost 15% or more | 2025 |
| GLORY-2 (phase 3)2 | Chinese adults with obesity | On the higher 9 mg dose, ~20% body-weight loss | 2025 |
In plain terms: in a large late-stage trial, the average person on the 6 mg dose lost about 14% of their body weight over roughly a year1. A separate trial testing a stronger 9 mg dose reached about 20%2. GLORY-1 also reported drops in liver fat and several heart-related risk markers.
Keep the honesty in view: these are strong phase-3 results, but in specific Chinese study populations, and mazdutide is not yet broadly approved.
Practical notes and handling
Mazdutide has been studied as a subcutaneous once-weekly injection with a gradual dose-increase schedule, the standard approach for easing early nausea in this drug class. This is an educational description of what the trials used, not guidance on use.
As with other GLP-1 / glucagon agonists, the most common reported side effects were gastrointestinal — nausea, diarrhoea, and vomiting — mostly during dose increases. Trials also tracked heart rate, which can edge up slightly with glucagon-active drugs.
Honest limitations
The key line: mazdutide is not a broadly approved medicine. As of 2026 it has completed phase-3 trials and entered regulatory review in China, but it is not approved by the FDA or EMA and remains investigational outside that process. Its strongest data are in Chinese populations, so how well the results generalise is still an open question. This page explains what it is and what the trials showed — not how to use it — and takes no position on sourcing.
Latest research
- GLORY-1 (2025) is the anchor phase-3 result: ~14% weight loss on 6 mg at 48 weeks in 610 Chinese adults, plus reductions in liver fat and cardiometabolic risk markers1.
- GLORY-2 (2025) pushed to a higher 9 mg dose and reported ~20% weight loss — moving mazdutide into the same range as the strongest incretin drugs2.
- Regulatory review is underway in China, while global development continues. We update this section as approvals or new trials report.
The short version
Mazdutide is an investigational GLP-1 / glucagon dual agonist, built from the natural hormone oxyntomodulin and developed largely in China. In phase-3 trials it produced about 14% weight loss on 6 mg and about 20% on 9 mg, with the strongest data in Chinese adults. It is not broadly approved. Educational overview only, not medical advice.