Retatrutide is being called the “next generation” weight loss injection. But what do the real results show so far?
Retatrutide is still in clinical testing, so no one can prescribe it yet. The early data has caught attention because participants in trials lost more weight than those on other medications like Wegovy or Mounjaro.
Below, we look at the verified trial results, what to expect in the first month, and why online “before and after” posts aren’t reliable evidence.
Retatrutide weight loss results: Phase 2 trial
The most up-to-date retatrutide weight loss results come from a phase 2 clinical trial.
The trial included 338 adults who had a body mass index (BMI) of 30 or higher, or 27 or higher with at least one weight-related condition. Participants received weekly injections for 48 weeks, with different dose groups compared to a placebo.
Average weight change at 48 weeks
People on the highest dose lost around 24% of their body weight after 48 weeks. That’s roughly one-quarter of total body weight on average and is the highest seen so far among obesity treatments.
For comparison, the new 7.2mg dose of Wegovy (semaglutide) led to an average loss of 20.7% after 72 weeks, while Mounjaro (tirzepatide) trials reported around 22.5%.
Retatrutide 1-month results: What to expect early on
Early weight loss with retatrutide begins quickly. In the phase 2 study, participants started to see measurable changes within four weeks of treatment.
By week four, the average weight loss ranged from 2% to 5%, depending on the dose. This early change was similar to what’s seen in the first month of other weight loss injections like Wegovy.
Retatrutide helps with weight loss by mimicking three natural hormones (GLP-1, GIP and glucagon). These hormones work together to reduce hunger, slow digestion and increase the body’s use of stored fat.
Other health effects seen in trials
Besides weight loss, trial participants saw improvements in:
- Blood sugar control (lower HbA1c levels)
- Blood pressure and cholesterol
- Liver fat reduction, which may help prevent fatty liver disease
These benefits were seen across doses but were strongest in higher-dose groups.
The early signals are encouraging, but we still need more evidence. Phase 3 clinical trials will help confirm the longer-term benefits and safety.
The risks of buying retatrutide online
Retatrutide is not yet approved for use in the UK. Clinical trials are ongoing, and the medication is only available to people taking part in those studies. Anyone claiming to use retatrutide outside a clinical trial cannot know for certain what they are taking.
On social media platforms like TikTok, you may see bodybuilders or gym-goers claiming to use retatrutide to “cut” or speed up results after a bulking phase. These claims are unlikely to be true. People in those groups would not qualify for current clinical trials.
So if they are using something labelled as retatrutide, it has almost certainly been bought from illegal or unregulated sellers. It is illegal in the UK to sell retatrutide for human use as the drug has not yet been approved.
When you see “retatrutide results” online, keep these signs of hype in mind:
- Links to sellers or product pages claiming to offer retatrutide, even if labelled “for research only.” These are not authorised for human use.
- Payments through WhatsApp, Telegram or cryptocurrency, which are common signs of unregulated sales.
- Discount codes or promotional offers used to encourage purchase or use of an unapproved product.
- Videos or posts suggesting retatrutide sales are legal in the UK. The medicine is still unapproved and cannot be prescribed.
- Extreme diet advice or rapid-weight-loss claims that make progress look faster than it really is.
- Before-and-after photos that look exaggerated, often using lighting or filters.
- Influencers discussing combinations with other drugs, such as tirzepatide or steroids, which makes any results unreliable.
If you come across claims to sell “research peptides” or “retatrutide vials”, avoid them as they could be dangerous.
For verified information on safe and legal access, see our guide on where to buy retatrutide.
Retatrutide phase 3 results: What’s next?
Retatrutide is now being studied in large phase 3 clinical trials known as the TRIUMPH studies, led by Eli Lilly. These trials are assessing how well retatrutide works for weight management and related health conditions, and whether it is safe enough for regulatory approval.
Most phase 3 trials are due to finish by mid-2026, so approval would not be expected before then.
If the results confirm safety and effectiveness, retatrutide will then be reviewed by regulators such as the MHRA in the UK before it can be approved for prescription use. Until that happens, it remains unapproved and unavailable in the UK.
Is retatrutide available in the UK? Safer options now
No, retatrutide is not available or licensed in the UK yet.
If you’re considering weight-loss medication, safe and approved alternatives include:
You can see how these options compare and review real Voy weight loss results.
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