What mazdutide is

Mazdutide (also identified as IBI362 or LY3305677, brand name Xinermei) is a once-weekly, subcutaneously injected peptide that activates two receptors: the GLP-1 receptor and the glucagon receptor ^[1]. Like other dual glucagon/GLP-1 agonists, the intent of adding glucagon-receptor activity is to combine appetite and glucose effects with increased energy expenditure. It is being developed by Innovent Biologics with Eli Lilly ^[1].

Unlike most compounds in this library, mazdutide has reached regulatory approval. In June 2025 it was approved in China for long-term body-weight management in adults meeting defined body-mass-index criteria, and in September 2025 it was approved in China for glycemic control in type 2 diabetes; it remains under study for fatty liver disease, obstructive sleep apnea, and other conditions ^[1]. Material sold by research-chemical vendors is not the approved pharmaceutical product and is offered for laboratory and research use only.

What the human research has measured

Mazdutide's development program includes randomized, double-blind, placebo-controlled trials through phase 3. In obesity, a phase 3 trial in China randomly assigned adults with obesity, or with overweight plus a weight-related condition, to two mazdutide doses or placebo for 48 weeks, with co-primary endpoints of percentage change in body weight and achieving a weight reduction of at least 5% ^[2]. An earlier phase 2 trial in Chinese overweight adults or adults with obesity (248 participants) measured percentage change in body weight over 24 weeks ^[5], and a phase 1 trial in 32 adults reported mean weight reductions of about -20.0% and -21.0% across two dose-escalation cohorts versus -0.1% with placebo at week 20 ^[6].

In type 2 diabetes, a phase 2 trial compared mazdutide against placebo and against open-label dulaglutide as a reference: mean HbA1c changes from baseline ranged from about -1.41% to -1.67% with mazdutide, compared with -1.35% for dulaglutide and 0.03% for placebo (all P<0.0001 versus placebo), with dose-dependent weight loss up to about -7.1% ^[3]. A phase 3 diabetes trial in 320 Chinese adults reported that the two mazdutide doses reduced HbA1c versus placebo by about -1.57% and -2.15% at week 24 ^[4].

This early evidence has been synthesized. A systematic review and meta-analysis of seven randomized controlled trials involving 680 participants pooled mazdutide's effects on weight and blood glucose against placebo in adults with and without diabetes ^[7], and additional meta-analysis has compared it against dulaglutide ^[8].

What the trials report on safety and adverse events

The randomized trials evaluated safety and tolerability alongside efficacy, and the meta-analysis explicitly set out to synthesize the safety as well as efficacy of mazdutide versus placebo ^[7]. As with the incretin drug class generally, gastrointestinal tolerability during dose escalation is a central concern, which is why the trials used stepwise dose-escalation regimens before reaching target doses ^[6].

Because much of the controlled evidence is recent and concentrated in Chinese trial populations, the long-term and cross-population safety database is still developing even though the drug is now approved in one country. None of this is a safety guarantee or a prediction for any individual. Material sold by research-chemical vendors is not the approved product and has not passed an equivalent evaluation. This is not medical advice; consult a qualified professional and read the studies directly.

How strong is the evidence

The evidence is characterized as strong relative to most compounds in this library: mazdutide has multiple randomized, placebo-controlled trials through phase 3, meta-analyses, and regulatory approval in one country ^[1][2][4][7]. "Strong" describes the design and quantity of the trials, not an endorsement, and the scope matters, much of the pivotal evidence comes from trials conducted in China, and the longest-term outcomes are still accumulating. It is also not a comparison verdict against other approved agents.

Nothing here is dosing, medical, or safety guidance. Read the studies themselves and consult a qualified professional. This page is a map to the evidence, not a recommendation.