China's Mazdutide Achieves Up to 14% Weight Loss in Major Phase 3 Trial Published in NEJM

In this phase 3 NEJM-published trial (GLORY-1), mazdutide — a GLP-1/glucagon dual agonist — produced significant weight loss in 610 Chinese adults with obesity or overweight over 48 weeks. The 6 mg dose achieved 14.01% body weight reduction at week 48 (vs. 0.30% for placebo), and the 4 mg dose achieved 11.00%. At week 48, 49.5% of participants on the 6 mg dose lost ≥15% of their body weight. Both doses improved all prespecified cardiometabolic measures. Discontinuation rates due to adverse events were remarkably low (0.5-1.5%), with GI side effects being mostly mild to moderate.

Phase 3, double-blind, placebo-controlled, randomized trial (GLORY-1) conducted in China. 610 adults aged 18-75 with BMI ≥28 (or ≥24 with comorbidities) were randomized 1:1:1 to mazdutide 4 mg, mazdutide 6 mg, or placebo for 48 weeks. Co-primary endpoints were percentage body weight change and proportion achieving ≥5% weight loss at week 32 using treatment-policy estimand analysis.

Mazdutide is China's homegrown competitor to tirzepatide and semaglutide, and this NEJM publication validates it as a serious contender. Its dual GLP-1/glucagon mechanism differs from tirzepatide's GLP-1/GIP approach, potentially offering distinct metabolic benefits. The very low discontinuation rate is particularly notable for a weight loss drug.

The weight loss drug market has been dominated by Novo Nordisk (semaglutide) and Eli Lilly (tirzepatide), both Western companies. Mazdutide from Innovent Biologics represents China's entry into this space with a distinct mechanism — targeting glucagon rather than GIP as the second receptor. This NEJM publication signals that mazdutide is a serious global competitor. Its unique GLP-1/glucagon mechanism may offer metabolic advantages, particularly for liver fat reduction, that differ from GLP-1/GIP drugs.

Conducted exclusively in Chinese adults, so results may not generalize to other populations with different BMI distributions and metabolic profiles. Chinese BMI thresholds for obesity (≥28) and overweight (≥24) are lower than Western standards. No active comparator arm (e.g., semaglutide or tirzepatide), so direct comparison with existing drugs requires cross-trial interpretation. 48 weeks is meaningful but not long-term safety data.