Orforglipron: a new GLP-1 treatment in tablet form for weight loss

Orforglipron (Foundayo): a new GLP-1 treatment in tablet form for weight loss

Orforglipron is an oral (non-peptide) GLP-1 receptor agonist that was recently approved in the USA (under the name Foundayo) for the treatment of adults with obesity or overweight with at least one weight-related comorbidity. In clinical studies, the treatment has shown efficacy in both weight loss and blood sugar control.

How does Orforglipron work? Treatment of obesity and type 2 diabetes

Orforglipron is a drug developed by Eli Lilly that belongs to the drug class of GLP-1 receptor agonists. These drugs activate the body's GLP-1 receptors, which are normally stimulated by a hormone released from the gut in connection with a meal.

Through this mechanism, the feeling of satiety increases, gastric emptying is delayed, and appetite decreases, which can facilitate weight loss. The drug also affects the brain's appetite-regulating centres, which can reduce hunger and what is sometimes described as "food noise".

In addition to the effects on appetite and satiety, GLP-1 receptor agonists also affect the body's blood sugar regulation. They stimulate insulin release from beta cells in the pancreas in a glucose-dependent manner, meaning the effect is greatest when blood sugar is elevated. Simultaneously, the release of glucagon – a hormone that otherwise raises blood sugar by stimulating the liver's glucose production – is inhibited.

Together, these effects contribute to improved blood sugar control, especially in people with type 2 diabetes, while the risk of low blood sugar (hypoglycaemia) is low when treated without the simultaneous use of other blood sugar-lowering drugs.

Unlike many established treatments, such as semaglutide (Wegovy, Ozempic) and tirzepatide (Mounjaro), which are given via injection, Orforglipron is a tablet.

A key difference is that Orforglipron is a so-called small molecule (non-peptide). Traditional GLP-1 drugs are peptides that are easily broken down in the gastrointestinal tract if taken by mouth. Orforglipron, however, is chemically designed not to be broken down in the same way, which enables treatment in tablet form.

This can provide a more practical treatment option, without the same requirements for fasting and strict dosing restrictions as some other oral GLP-1 drugs.

How does Orforglipron differ from other oral GLP-1s?

The main difference lies in the chemical structure. Orforglipron is a synthetic small molecule (non-peptide), which allows it to be taken as a regular tablet and absorbed via the gastrointestinal tract. Semaglutide, on the other hand, is a peptide, which means it is in most cases given as an injection, though it has also been developed in tablet form (Rybelsus).

The oral form of semaglutide (Rybelsus), however, requires careful dosing. The tablet needs to be taken on an empty stomach with a small amount of water, and one should then wait at least 30 minutes before eating or drinking to ensure absorption.

Orforglipron is developed to be taken without the same strict dosing requirements, which can make the treatment more practical in everyday life.

Both drugs work by activating GLP-1 receptors, which affects appetite, satiety, and blood sugar regulation.

Is Orforglipron approved?

Orforglipron has been approved in the USA by the American Food and Drug Administration, the FDA (2026), for the treatment of obesity and overweight with weight-related complications.

However, the drug is not yet approved by the European Medicines Agency (EMA), which means it is currently not available as a routine treatment in Europe.

Potential advantage of Orforglipron

An advantage of Orforglipron is that it may offer a needle-free alternative to today's injectable treatments, in the form of a tablet.

For people who experience discomfort regarding injections, or who find the handling of syringes practically difficult, this can provide a more accessible treatment option.

Results from the ATTAIN clinical trial programme

In the ATTAIN clinical trial programme, which includes people with obesity, Orforglipron has shown clinically significant weight loss compared to placebo. At higher doses, participants have on average achieved a weight loss of approximately 10–12% of body weight, with some studies showing slightly higher or lower effects depending on the population and study design.

Throughout the programme, improvements were also observed in cardiometabolic risk factors, including waist circumference, blood lipids, and blood pressure.

The drug could thus become a relevant treatment option for both obesity and related metabolic conditions.

Possible side effects

The most common side effects of Orforglipron are, similar to most GLP-1-based treatments, related to the gastrointestinal tract and include nausea, diarrhoea, vomiting, and constipation.

Since the drug works by delaying gastric emptying and affecting the motility of the gastrointestinal tract, this is an expected pharmacological effect, especially during the first weeks of treatment. In clinical studies, side effects have generally been mild to moderate and similar to the safety profile known from other GLP-1 receptor agonists.

The symptoms often subside over time as the body adapts to the treatment. To reduce the risk of side effects, it is important to start with a low dose and gradually escalate the treatment.

Diet-related measures, such as eating smaller portions and avoiding foods that are very high in fat, can also help reduce stomach discomfort during treatment.

However, it is important to consider that rapid weight loss, regardless of the treatment method, can lead to loss of muscle mass. Treatment with incretin-based drugs like Orforglipron is therefore recommended to be combined with sufficient protein intake and regular strength training to reduce loss of muscle mass and promote a healthy body composition.

Frequently asked questions about Orforglipron

Is Orforglipron a tablet?

Yes, Orforglipron is a GLP-1 receptor agonist developed to be taken in tablet form. It is a so-called small molecule (non-peptide), which allows it to be taken orally instead of as an injection.

Is Orforglipron approved yet?

Yes, in the USA, Orforglipron was FDA-approved on 1 April 2026 under the brand name Foundayo for adults with obesity, or overweight with at least one weight-related complication. In Europe, the drug is not yet approved by the EMA, meaning availability still differs between markets.

How effective is Orforglipron?

In the ATTAIN clinical trial programme, which includes people with obesity, Orforglipron has shown clinically significant weight loss compared to placebo. At higher doses, participants have on average achieved a weight loss of approximately 10–12% of body weight, with some studies showing slightly higher or lower effects depending on the population and study design. Throughout the programme, participants also showed improvements in cardiometabolic risk factors, including waist circumference, blood lipids, and blood pressure.

Sources

Eli Lilly. https://investor.lilly.com/news-releases/news-release-details/fda-approves-lillys-foundayotm-Orforglipron-only-glp-1-pill

The New England Journal of Medicine. Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment DOI: 10.1056/NEJMoa2511774

FDA. https://www.fda.gov/news-events/press-announcements/fda-approves-first-new-molecular-entity-under-national-priorit

International Journal of Molecular Sciences. Orforglipron: A Comprehensive Review of an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity and Type 2 Diabetes doi: 10.3390/ijms27031409