You’ve heard of Wegovy weight loss injections, which use the active ingredient semaglutide. But what about mazdutide, a new weight loss medicine on the horizon?
Mazdutide was approved in China in 2025 for weight management and type 2 diabetes. While it's not yet available in the UK, larger international trials are underway to confirm its safety and effectiveness. Below, we explore how these two medications compare.
Key Takeaways
- Mazdutide is approved in China for weight management and type 2 diabetes but not yet available in the UK
- Mazdutide targets GLP-1 and glucagon, while semaglutide targets GLP-1 only
- One head-to-head trial showed greater weight loss with mazdutide (10.29% vs 6%)
- Both are once-weekly injections with similar mild digestive side effects
- Semaglutide is available in the UK now; mazdutide may be approved by late 2026 or 2027 if trials are successful
What is mazdutide?
Mazdutide is a weekly weight loss injection used for weight management and type 2 diabetes. The medication is approved in China, where it's sold under the brand name Xinermei by Innovent Biologics. It is not approved anywhere else in the world.
Eli Lilly is conducting larger global studies to evaluate mazdutide's effectiveness across different populations. If these studies prove successful, it may receive UK approval between 2026 and 2027.
Mazdutide vs semaglutide
Here’s how these two weight loss medications stack up.
How do they work?
Both medications work by mimicking natural gut hormones, but they target different combinations.
Semaglutide mimics GLP-1, which helps reduce appetite, slows digestion, and supports healthy blood sugar levels.
Mazdutide brings on the effects of GLP-1 but also glucagon, another hormone. Glucagon increases energy use and fat burning. Together, this dual action suppresses appetite, reduces calorie intake, and boosts fat metabolism, leading to weight loss and improved metabolic health.
Clinical results: Which one works better for weight loss?
Here’s what the research says. FYI: the below semaglutide figures are estimated from 72-week data.
After 60 weeks:
- Semaglutide 2.4mg - 16% mean weight loss
- Semaglutide 7.2mg - 19% mean weight loss
- Mazdutide 9mg - 20% mean weight loss
However, these results come from different studies with different patient populations, making direct comparison difficult.
In a head-to-head comparison in China, mazdutide 6mg drove more weight loss than semaglutide in people with type 2 diabetes (10.29% vs 6%). It's worth noting that mazdutide is being studied at higher doses up to 16mg, which may widen this gap even further.
Other benefits and effects
Beyond weight loss, both medications deliver improvements across multiple areas of metabolic health.
Mazdutide has shown improvements in blood sugar, cholesterol and blood pressure in Chinese studies. It also reduced liver fat in people with fatty liver disease. Researchers are now exploring its potential in conditions such as MAFLD, obstructive sleep apnoea, alcohol use disorder, heart failure and teenage obesity.
Semaglutide also improves blood sugar, lowers blood pressure and reduces cardiovascular risk. It has a much larger evidence base and is licensed for reducing major cardiovascular events. Check out our guide on the health benefits of semaglutide to learn all about it.
Combined outcomes
In one head-to-head trial in Chinese adults with type 2 diabetes and obesity 48% of people on mazdutide reached healthy blood sugar levels (HbA1c below 7%) and at least 10% weight loss, compared with 21% on semaglutide.
These are early findings, and larger global trials are needed to confirm whether the same results appear in other populations.
Side effects
The side effects for mazdutide and semaglutide are similar and tend to be mild. Common side effects include:
- Diarrhoea
- Nausea
- Vomiting
Both medications appear safe based on current trial data, with side effects typically manageable through dose adjustment. Semaglutide has a more established safety profile due to its extensive use in diverse populations worldwide, while mazdutide's safety data comes mainly from studies in China.
Side effects support at Voy
"If you're using Voy and you experience any side effects, rest assured that our expert clinicians are just a message or phone call away. They can adjust your dose, prescribe medication to ease your symptoms, or simply offer reassurance.
Everyone responds differently to weight loss treatment and we'll help you find what feels right for you."
Dosing and how to use
Both medicines are weekly injections but they come in different doses.
- Semaglutide doses are 0.25mg, 0.5mg, 1mg, 1.7mg, and 2.4mg (with 7.2mg in development)
- Mazdutide doses approved in China are 2mg, 4mg, and 6mg, with doses up to 16mg being studied in clinical trials.
With either medicine, you start on the lowest strength and gradually increase every four weeks. This reduces your risk of side effects.
Availability and cost
Semaglutide is available in the UK both through the NHS and private prescription. NHS availability depends on meeting specific eligibility criteria. Private treatment costs vary between providers depending on the dose and level of service provided.
Mazdutide is not available in the UK or anywhere outside of China. If trials are successful, mazdutide could potentially be approved by 2026 or 2027. Pricing will likely be comparable to other weight loss medications currently available in the UK.
Mazdutide vs semaglutide: which is better for weight loss?
From what we know so far, mazdutide showed stronger results in a head-to-head trial with Chinese adults who had type 2 diabetes. But this is just one study, and mazdutide hasn't been tested as widely as semaglutide yet.
Semaglutide has been extensively researched worldwide, with proven safety and effectiveness. It's also available now, while mazdutide may not reach the UK until 2027.
The best medication for you depends on how well you tolerate it and whether you maintain it alongside lifestyle changes. Everyone responds differently to these medications.
While mazdutide isn't available yet, effective weight loss medications like Wegovy and Mounjaro are available now through our weight loss programme.
Take our quiz to see if you’re eligible.
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