Orforglipron

Orforglipron is a GLP-1 receptor agonist that’s currently being developed by the pharmaceutical company Eli Lilly – the same company that makes the GLP-1 weight loss injection Mounjaro. It’s being tested as a treatment for type 2 diabetes and weight loss (with or without diabetes). If approved, this daily tablet could be a more patient-friendly alternative to weekly weight loss injections.

Orforglipron works by mimicking the hormone GLP-1, a natural hormone that controls hunger, digestion, and blood sugar levels. After taking orforglipron, the body thinks GLP-1 levels are high, and responds by:

• reducing how hungry you feel
• slowing down digestion
• lowering blood sugar levels

By improving blood sugar control, orforglipron is an effective treatment for people with type 2 diabetes. It’s also a useful medication to support weight loss as it slows down how quickly your stomach empties while also reducing hunger cues sent from the brain – helping you to eat less and feel fuller for longer.

Orforglipron has not yet been licensed for use in the UK or anywhere else, as clinical trials are still ongoing, but results look promising. As of April 2025, the medication is currently in phase 3 of clinical trials, which means thousands of people are set to take orforglipron to see how effective it is for type 2 diabetes and obesity and to monitor side effects.

Phase 3 trials

Although the research from phase 3 trials is still in progress, a press release from Eli Lilly suggests some impressive results. People taking 36mg of orforglipron for 40 weeks lost an average 7.9% of their body weight, or 7.3kg. They also reduced their long-term blood sugar levels (HbA1c) by 1.5%.

Phase 2 trials

Results from earlier phase 2 studies involving a smaller number of people were also positive.

Weight loss results

After taking orforglipron for 26 weeks, participants lost an average of 8.6 to 12.6% of their body weight compared to just 2% in people who did not take orforglipron (the placebo group). By week 36, this had increased to a loss of 9.4 to 14.7% compared to 2.3% in the placebo group.

Type 2 diabetes results

In a different phase 2 study, orforglipron was compared to another GLP-1 medication (dulaglutide) in people with type 2 diabetes. After 26 weeks, long-term blood sugar levels had dropped 2.1% in people taking orforglipron, 1.1% in people taking dulaglutide, and 0.4% in people taking a placebo. Average weight loss was 10.1kg with orforglipron, 3.9kg with dulaglutide, and 2.2kg for the placebo group.

Phase 1 trials

A phase 1 study tested orforglipron in people with type 2 diabetes. After 12 weeks, long-term blood sugar levels dropped 1.5 to 1.8% with orforglipron, whereas participants not taking it had blood sugar levels dropping by only 0.4%.

Participants taking the medication lost between 0.24 to 5.8kg compared to an average 0.5kg loss in participants who were on the placebo.

Data from clinical trials suggest that orforglipron could be an easy-to-use, effective treatment for type 2 diabetes and obesity.

Blood sugar (glucose) stabilisation

Orforglipron works in 2 ways to improve blood sugar levels:

1. Increases insulin secretion – the hormone that lowers blood sugar levels.
2. Decreases glucagon secretion – the hormone that raises blood sugar levels.

This makes it an effective treatment for type 2 diabetes, where insulin is not working effectively and blood sugar levels are too high.

Weight loss support

Several studies have demonstrated that orforglipron helps people lose weight, with 1 study finding that 46 to 75% of people taking the medication lost at least 10% of their body weight in 36 weeks. The medication does this by making people feel fuller for longer, making it easier to eat less and lose weight.

Ease of use

As it’s taken as a tablet, orforglipron is a quicker and easier option compared to many other GLP-1 medications like semaglutide and tirzepatide. There is no need to inject yourself or to order needles and dispose of them, to take orforglipron, you just need to swallow a tablet every day.

Most side effects listed in clinical trials were mild and were similar to those found with licensed GLP-1 medications like Wegovy, Nevolat, Ozempic, and Mounjaro.

Gastrointestinal side effects are most common, for example, you may experience:

• nausea
• vomiting
• diarrhoea
• constipation

More serious side effects were much less common. As research continues, the related side effects and how often they happen will become clearer. We will also learn more about who can safely take this medication and who should avoid it.

Orforglipron vs alternative weight loss treatments

Specific clinical research comparing orforglipron is still limited, but here is an overview of studies currently available which measure the effectiveness of orforglipron, tirzepatide (Mounjaro), and semaglutide (Wegovy):

*It’s important to note that the other medications were taken for more than twice as long as orforglipron and needed to be injected. So, this research shows that it can be an effective treatment.

Orforglipron vs alternative type 2 diabetes treatments

Orforglipron is effective for the treatment of type 2 diabetes and may be able to improve blood glucose regulation in a similar way to other GLP-1 medications without the need for injections. While further research is needed, here are the current results comparing orforglipron with current approved type 2 diabetes injections:

There is another GLP-1 tablet for diabetes that’s currently available in the UK called Rybelsus. Containing the active ingredient semaglutide, 14mg of Rybelsus was found to lower HbA1c levels by 1.3% after 52 weeks, suggesting orforglipron could be more effective (although more research is needed to say for sure). Rybelsus is only licensed for type 2 diabetes in the UK and not for weight management.

➤ For more information and comparisons on weight loss and type 2 diabetes medication containing GLP-1 receptor agonists, read our comparison page on Wegovy vs Mounjaro vs Ozempic.

Eli Lilly aims to submit the medication for approval from the US FDA (Food and Drug Administration) as a weight loss treatment by the end of 2025 and as a type 2 diabetes treatment by 2026. Even if approved by the FDA, Eli Lilly will need to submit a proposal along with evidence to the UK healthcare governing body, the National Institute for Health and Care Excellence (NICE), for it to be approved in the UK.

If everything goes to plan, orforglipron may be available in the UK from 2026 onwards, though this is just an estimated date.