Mazdutide

Established jabs like Wegovy are a 'one-pedal' weight-loss car that mostly eases off the accelerator (eating less). Mazdutide adds a second pedal that also burns a bit more fuel and cleans the engine (the liver). This car has only passed its full road tests and been licensed in one country (China). In the UK it has not been approved, and the versions sold online are like unbranded parts from an unknown workshop with no guarantee of what is in the box.

A synthetic analogue of the gut hormone oxyntomodulin that activates the GLP-1 receptor (reducing appetite, slowing gastric emptying, enhancing glucose-dependent insulin release) and the glucagon receptor (increasing energy expenditure and promoting hepatic fat breakdown). It is given as a once-weekly subcutaneous injection. Fatty-acid acylation extends its half-life via albumin binding.

Research contexts. Not proven uses, and not recommendations.

Strong by the standards of most peptides on this site. Mazdutide has completed multiple randomised, placebo-controlled human trials. An early Phase 1b dose-escalation study and a two-part Phase 2 trial in Chinese adults were published in eClinicalMedicine (2022) and Nature Communications (2023) respectively. The pivotal Phase 3 GLORY-1 obesity trial (610 Chinese adults) was published in the New England Journal of Medicine in 2025, reporting around 14% mean weight loss over 48 weeks at its higher tested level, with a low discontinuation rate. A separate higher-dose Phase 3 trial (GLORY-2) reported top-line mean weight loss of roughly 20%. Two Phase 3 type 2 diabetes trials were published back-to-back in Nature in 2025. China's NMPA approved mazdutide for chronic weight management in June 2025 and for glycaemic control in type 2 diabetes in September 2025. Trial populations were almost entirely Chinese, so efficacy and safety in other ethnic groups are not yet established. There is no completed long-term cardiovascular outcome trial.

• !Not licensed by the MHRA, EMA or FDA. Approval to date is China-only (NMPA, 2025); any UK supply is unlicensed.
• !Material sold to UK consumers as 'mazdutide' from research-chemical vendors is unregulated, of unverified identity, purity and sterility, and typically labelled 'not for human consumption'.
• !Almost all clinical evidence comes from Chinese populations; how well it generalises to other groups is unproven.
• !No completed long-term cardiovascular outcome data. Chronic glucagon-receptor agonism is a relatively new mechanism with limited very-long-term safety follow-up.
• !Gastrointestinal adverse events (nausea, vomiting, diarrhoea) are common, as with all GLP-1 class drugs. A small mean heart-rate increase has been observed.
• !Glucagon agonism can theoretically raise blood glucose and affect hepatic metabolism. Trials used careful medical monitoring that unsupervised self-administration bypasses.
• !Class-wide GLP-1 cautions apply: pancreatitis signal, gallbladder events, and the thyroid C-cell tumour signal seen in rodents for the class.

Not a licensed medicine in the UK. Mazdutide holds marketing approval only from China's NMPA (chronic weight management, June 2025; type 2 diabetes, September 2025). It has no MHRA, EMA or FDA authorisation. In UK terms it is an unlicensed/investigational drug. It is not available on the NHS or by private prescription, and any material sold online to UK buyers is an unlicensed 'research chemical', typically labelled 'not for human consumption' and entirely outside MHRA quality oversight.

• · Phase 3· Completed / published (NEJM 2025); supported NMPA approval

  GLORY-1: efficacy and safety of mazdutide in Chinese participants with overweight or obesity

  610 Chinese adults; mazdutide at two dose levels vs placebo over 48 weeks; primary weight-loss endpoints met.

• · Phase 3· Top-line results reported (~20% mean weight loss); primary and key secondary endpoints met

  GLORY-2: higher-dose mazdutide in Chinese adults with moderate-to-severe obesity

  Higher-dose programme supporting a supplementary NMPA application.

• · Phase 3· Completed; two trials published back-to-back in Nature (2025); supported NMPA diabetes approval

  Mazdutide Phase 3 programme in Chinese adults with type 2 diabetes

  Glycaemic control and weight outcomes in type 2 diabetes.

1. 01
   Mazdutide for Chinese adults with overweight or obesity (GLORY-1): a randomised, double-blind, placebo-controlled phase 3 trial, New England Journal of Medicine (2025)

   Pivotal Phase 3 obesity trial in 610 Chinese adults; ~14% mean weight loss over 48 weeks. Exact PMID/DOI not confirmed here, so the link is a PubMed search.

2. 02
   A phase 2 randomised controlled trial of mazdutide in Chinese overweight adults or adults with obesity, Nature Communications (2023)

   Two-part, double-blind, placebo-controlled Phase 2 dose-finding trial.

3. 03
   Safety and efficacy of a GLP-1 and glucagon receptor dual agonist mazdutide (IBI362) 9 mg and 10 mg in Chinese adults with overweight or obesity: a randomised, placebo-controlled, multiple-ascending-dose phase 1b trial, eClinicalMedicine (Lancet Discovery Science) (2022)

   Early human dose-escalation safety/efficacy data.

4. 04
   Innovent Announces Mazdutide, First Dual GCG/GLP-1 Receptor Agonist, Received Approval from China's NMPA for Chronic Weight Management, Innovent Biologics / PR Newswire (2025)

   Primary-source announcement of the June 2025 NMPA weight-management approval.