At its highest tested dose, the dual-hormone drug mazdutide cut body weight by about 11 percent in adults with obesity, and the effect grew with every step up in dose. A pooled analysis of nine trials also found the drug beat an established GLP-1 injection in people with diabetes. The weaker part of the story is how much to trust the obesity figure.
The synthesis, published July 6 in Diabetes, Obesity and Metabolism ↗, gathered nine randomized controlled trials with 2,292 participants, most at low risk of bias, drawn from searches of PubMed, Scopus, Web of Science, and ClinicalTrials.gov, and graded the certainty of each result with the GRADE system. Mazdutide ↗, developed as IBI362, is a dual agonist: it activates the GLP-1 receptor ↗ that Ozempic-style drugs hit to curb appetite, and also the glucagon receptor ↗, which nudges the body to burn more energy and acts on the liver. That second arm is what separates it from the single-target GLP-1 drugs.
In adults with obesity and no diabetes, weight fell further at each dose: about 6.6 percent at 3 milligrams, 9.9 percent at 4, and 11.1 percent at 6, all measured against placebo. A clean dose-response is usually a good sign that a drug is really doing the work. But the reviewers rated the certainty of these obesity numbers "very low," because the trials were few and disagreed with each other more than a tidy average lets on.
The diabetes results held up better. At 4 and 6 milligrams, mazdutide lowered both weight and HbA1c, the three-month blood-sugar average, against placebo, and the reviewers rated that evidence "moderate." It also outperformed dulaglutide ↗, the weekly GLP-1 drug sold as Trulicity, on both measures. The metabolic reach went past the scale: waist circumference, blood lipids, liver enzymes, and uric acid all improved, the kind of liver-and-lipid movement the glucagon arm is expected to drive.
The cost was the usual one. Gastrointestinal side effects, the nausea and vomiting familiar to anyone on these drugs, were more frequent on mazdutide, but serious adverse events and the share of patients quitting the drug were about the same as the comparators. No new safety flag emerged from the pooled data.
The finding lands on a drug this section has covered once before, when a single head-to-head trial had mazdutide beating semaglutide by more than double the margin ↗ in diabetes. A meta-analysis is a sturdier thing than one trial, but it inherits the weakness of what it pools: nine trials run, in the authors' word, "predominantly" in Chinese adults, which is why they close by asking for longer studies in more varied populations before anyone reads the dulaglutide win as settled.
For now the picture is a dual agonist with a convincing dose-response and a metabolic profile that stretches past appetite into the liver, resting on obesity evidence the reviewers themselves call shaky and diabetes evidence they call middling. The molecule is worth watching. The confidence intervals say wait for the bigger trials.