Mazdutide remains China-only as Eli Lilly publishes a 179-person US phase 2 trial

Mazdutide, a once-weekly injectable that acts on both GLP-1 and glucagon receptors, remains a China-only product even after Eli Lilly published a US phase 2 trial of the drug in The Lancet Diabetes and Endocrinology on August 21, 2026 ^[1]. China's regulator approved it for chronic weight management on June 27, 2025 and for blood sugar control in type 2 diabetes on September 19, 2025 ^[1].

As of September 5, 2026, mazdutide is not approved by the FDA, and it had not been approved by any regulator outside China as far as that review could determine ^[1]. A pipeline roundup published September 2, 2026 states that no FDA submission has been announced for mazdutide and that US development remains in earlier-stage trials ^[2].

Where the drug stands

Mazdutide was discovered by Eli Lilly, which holds rights outside China, and licensed to Innovent Biologics in August 2019 for development and commercialization in China ^[1]. Innovent runs the Chinese trials — GLORY in obesity, DREAMS in type 2 diabetes — and sells the drug there under the brand name Xinermei ^[1]. Lilly's development code for the molecule is LY3305677 ^[1].

The largest Chinese obesity trial, GLORY-1, enrolled 610 Chinese adults for 48 weeks and reported average weight change of -11.00% at 4 mg and -14.01% at 6 mg, compared with +0.30% for placebo ^[1]. At week 48, 35.7% of the 4 mg group, 49.5% of the 6 mg group and 2.0% of the placebo group had lost at least 15% of body weight; discontinuation because of adverse events was 1.5%, 0.5% and 1.0% respectively ^[1]. A later trial, GLORY-2, tested a 9 mg dose in 462 Chinese adults with a BMI of 30 or higher over 60 weeks and reported -18.55% on average, and -20.08% among participants without type 2 diabetes, with 2.9% discontinuing for side effects versus 0% on placebo ^[1].

The US data come from a separate, smaller Lilly trial (NCT06124807) of 179 adults. At 32 weeks, weight change averaged -7.3% for 3 to 6 mg, -15.6% for 10 mg and -18.1% for 16 mg, against -0.9% for placebo; 20% of participants on 16 mg stopped the drug because of adverse events ^[1]. That article gives two different completion windows for the trial, January 2025 in one section and July 2025 in another ^[1].

Side effects in GLORY-1 followed the pattern seen across this drug class: nausea, diarrhea and vomiting were most common, concentrated during dose increases, and most events were mild to moderate ^[1]. No large cardiovascular outcomes trial for mazdutide has been published ^[1]. GLORY-1 was run in Chinese adults, and whether the same safety profile would hold in US populations has not been studied ^[1].

Why it matters for patients

Mazdutide is not a component of any FDA-approved drug, so no US pharmacy can lawfully compound or dispense it ^[1]. The FDA has warned companies selling mazdutide labeled "for research purposes," and its December 10, 2024 warning letter to Summit Research Peptides named mazdutide among unapproved drugs sold as research chemicals ^[1]. That means any mazdutide offered to US buyers sits outside the approved supply chain.

Cross-trial comparisons with US-approved drugs are unreliable, because the populations, baseline body weights and trial lengths differ ^[1]. Chinese guidelines use a lower BMI threshold for obesity (28) than the global standard of 30, so the same percentage weight loss reflects fewer pounds in the GLORY-1 population ^[1].

Patients in the US currently have two approved incretin options in this category: semaglutide (Ozempic, Wegovy, Rybelsus) and tirzepatide (Mounjaro, Zepbound) ^[1]. Survodutide, another GLP-1/glucagon dual agonist, is investigational and in phase 3 but made by different companies ^[1].

What happens next

There are no dated US milestones for mazdutide. Lilly has announced no phase 3 program and no FDA filing ^[1][2]. In China, Innovent said on November 19, 2025 that it plans a marketing application for the 9 mg dose, and head-to-head and sleep apnea trials are registered there ^[1]. Whether mazdutide is ever submitted to the FDA has not been disclosed.