What is Foundayo?
Foundayo is the brand name for orforglipron, a once-daily oral GLP-1 receptor agonist tablet developed by Eli Lilly. Foundayo was authorised by the Medicines and Healthcare products Regulatory Agency (MHRA) on 10 August 2026 in the UK, making it the first country in Europe to approve it. Foundayo was previously approved by the US Food and Drug Administration (FDA) on 1 April 2026 for chronic weight management in adults with obesity, or overweight with at least one weight-related comorbidity, alongside a reduced-calorie diet and increased physical activity. The April US authorisation was for weight management rather than treatment of type 2 diabetes. It was the second once-daily oral GLP-1 medicine authorised for chronic weight management in the US, following oral Wegovy tablets (semaglutide).
Foundayo is licensed in the UK for weight management in adults with a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related comorbidity, alongside a reduced-calorie diet and increased physical activity. It is also licensed to improve blood glucose control in adults with insufficiently controlled type 2 diabetes.
Unlike injectable weight-management treatments such as Mounjaro (tirzepatide) and Wegovy (semaglutide), Foundayo is taken as a tablet and does not require self-injection.
Orforglipron is a small-molecule, non-peptide GLP-1 receptor agonist. Foundayo can be taken once daily with or without food and without water restrictions. This differs from the Wegovy tablet, which must be taken on an empty stomach with a small amount of water, after which food, other drinks and other oral medicines should be avoided for at least 30 minutes.
Eli Lilly has submitted orforglipron for regulatory approval for weight management and/or type 2 diabetes in more than 40 countries and has said it plans to launch in each market shortly after approval.
How does Foundayo work?
Foundayo contains orforglipron, a small-molecule GLP-1 receptor agonist. It binds to and activates the human GLP-1 receptor, a natural hormone released by the gut after eating. By activating GLP-1 receptors, Foundayo can support weight management through several mechanisms:
- Reducing appetite and food cravings, helping patients feel satisfied with smaller portions.
- Slowing gastric emptying, allowing food to remain in the stomach for longer.
- Helping to regulate blood sugar levels by stimulating insulin release and reducing glucagon secretion.
These are the same core mechanisms through which injectable GLP-1 treatments such as Mounjaro and Wegovy support weight loss. However, Mounjaro additionally activates GIP (glucose-dependent insulinotropic polypeptide) receptors, which may contribute to the greater average weight loss observed in Mounjaro clinical trials compared with GLP-1-only treatments.
How is Foundayo different from Mounjaro?
Foundayo and Mounjaro are both manufactured by Eli Lilly but differ in their formulation, delivery method, mechanism of action and clinical weight loss outcomes.
- Mounjaro (tirzepatide) is a once-weekly injection that acts on both GLP-1 and GIP receptors. In the SURMOUNT-1 clinical trial, patients taking the highest dose of Mounjaro (15mg) lost an average of 22.5% of their body weight over 72 weeks.
- Foundayo (orforglipron) is a once-daily oral tablet that acts on the GLP-1 receptor only. In the ATTAIN-1 Phase 3 trial, patients taking the highest daily dose lost an average of approximately 11% of their body weight over 72 weeks.
Injectable Mounjaro currently demonstrates greater average weight loss in clinical trials. However, Foundayo may be a suitable option for patients who prefer a tablet over injections, those who have difficulty with self-injection or those looking to maintain weight loss achieved through injectable treatment.
How does Foundayo compare to the Wegovy Pill?
Both Foundayo and the Wegovy pill (oral semaglutide) are oral GLP-1 weight loss treatments, but they differ in their formulations and administration requirements.
The oral Wegovy pill is a peptide-based treatment that must be taken once daily on an empty stomach, with a small amount of water. Patients should avoid eating, drinking or taking other oral medication for at least 30 minutes after taking it.
Foundayo is a non-peptide, small-molecule treatment that can be taken once daily at any time of day, with no restrictions on food or water. This can make Foundayo easier to fit around meals for some patients.
In terms of weight loss results, the Wegovy pill demonstrated an average weight loss of approximately 13.6% over 64 weeks in its Phase 3 trial, whilst Foundayo showed an average weight loss of approximately 11% over 72 weeks at the highest dose.
Is Foundayo the same as orforglipron?
Yes. Orforglipron is the active ingredient in Foundayo. Foundayo is Eli Lilly's brand name for the medicine.
Orforglipron was studied under its ingredient name for several years before the Foundayo brand name was confirmed, which is why much of the published research and news coverage still refers to it as orforglipron.
How is Foundayo taken?
Foundayo is taken as one tablet once a day. The tablet should be swallowed whole and should not be broken, crushed or chewed. It can be taken at any time of day with or without food and with or without water.
Treatment begins at a starting dose of 0.8mg, which is gradually increased over several months to allow the body to adjust and to help reduce gastrointestinal side effects. The currently approved US regimen is:
- Weeks 1 to 4: 0.8mg once daily (starting dose)
- Weeks 5 to 8: 2.5mg once daily
- Weeks 9 to 12: 5.5mg once daily
- Week 13 onwards: the dose may be further increased to 9mg, 14.5mg or 17.2mg once daily, depending on individual response and tolerability
- UK patients should follow the dosing schedule in the UK Patient Information Leaflet and the instructions given by their prescriber, as UK prescribing information takes precedence over information authorised in other countries.
If a dose is missed, it should be taken as soon as possible on the same day. No more than one tablet should be taken per day. Always follow the dosage instructions provided by your prescriber.
How much weight can you lose on Foundayo?
The weight loss achieved with Foundayo has been evaluated in two Phase 3 clinical trials:
- In the ATTAIN-1 trial (adults with obesity or overweight without type 2 diabetes), participants taking the highest dose lost an average of approximately 11% of their body weight (around 25 pounds or 11 kg) over 72 weeks, compared to approximately 2% in the placebo group.
- In the ATTAIN-2 trial (adults with obesity or overweight and type 2 diabetes), participants taking the highest dose lost an average of approximately 10.5% of their body weight (around 23 pounds or 10 kg) over 72 weeks.
- In the ATTAIN-MAINTAIN trial, patients who switched from injectable Wegovy or Mounjaro to Foundayo were able to maintain the majority of their previously achieved weight loss over 52 weeks, whereas the placebo group experienced weight regain.
Individual results may vary depending on factors such as starting weight, dose, adherence, diet and exercise habits and how well the treatment is tolerated.
Can Foundayo be used after stopping Mounjaro or Wegovy?
Early clinical evidence suggests that Foundayo may help maintain weight loss achieved after injectable GLP-1 treatment. In the ATTAIN-MAINTAIN trial, participants who had previously completed 72 weeks of treatment with Mounjaro or Wegovy were re-randomised to receive either Foundayo or placebo.
Those who switched to Foundayo maintained the majority of their previously achieved weight loss, whereas the placebo group experienced significant weight regain. This suggests that Foundayo could serve as a convenient oral option for patients who wish to transition from injectable treatment to an oral tablet whilst preserving their weight loss outcomes.
What are the side effects of Foundayo?
The side effect profile of Foundayo observed in clinical trials is consistent with other GLP-1 receptor agonists. The most commonly reported side effects are gastrointestinal and tend to be mild to moderate in severity:
- Nausea
- Constipation
- Diarrhoea
- Vomiting
- Indigestion (dyspepsia)
- Abdominal pain
- Headache
- Bloating (abdominal distension)
- Fatigue
- Belching (eructation)
- Gastro-oesophageal reflux
- Flatulence
- Hair loss
These side effects are generally most pronounced during the dose escalation phase and tend to ease as the body adjusts to the treatment. In the ATTAIN-1 trial, approximately 6 to 10% of participants discontinued treatment due to gastrointestinal adverse events at higher doses, compared with approximately 4% in the placebo group.
Is Foundayo available in the UK?
Foundayo was authorised by the MHRA on 10 August 2026 for weight management and type 2 diabetes, making the UK the first country in Europe to approve it. It is a prescription-only medicine, so it can only be supplied following an online consultation and a prescription from a registered prescriber.
It is not currently available on the NHS. This will depend on a future evaluation by the National Institute for Health and Care Excellence (NICE).
How much will Foundayo cost in the UK?
UK pricing for Foundayo has not been confirmed yet.
Now that it has MHRA marketing authorisation, private market pricing will depend on manufacturing costs and the competitive landscape with existing injectable treatments such as Mounjaro and Wegovy. As a small-molecule tablet, Foundayo is generally simpler and less expensive to manufacture than peptide-based injectable treatments, which may support more competitive pricing over time.
Where can I buy Foundayo in the UK?
Foundayo is now MHRA-approved in the UK, but it is not yet available to buy through Pharmica. As with all prescription-only medicines, only order from a GPhC-registered UK pharmacy after completing a consultation to assess your eligibility.
What weight loss treatments are currently available?
Other weight loss treatments that are currently available at Pharmica are:
Sources:
- FDA: Approves First New Molecular Entity Under National Priority Voucher Program. [Accessed 8th April 2026]
- Eli Lilly: FDA approves Lilly's Foundayo (orforglipron), the only GLP-1 pill for weight loss that can be taken any time of day without food or water restrictions. [Accessed 8th April 2026]
- Eli Lilly: Foundayo (orforglipron) prescribing information and patient site. [Accessed 8th April 2026]
- Wharton S, et al. Orforglipron, an Oral GLP-1 Receptor Agonist for Obesity Treatment, New England Journal of Medicine, 2025. [Accessed 8th April 2026]
- Horn DB, et al. Orforglipron, an oral small-molecule GLP-1 receptor agonist, for the treatment of obesity in people with type 2 diabetes (ATTAIN-2), The Lancet, 2025. [Accessed 8th April 2026]
- MHRA: UK first in Europe to authorise orforglipron for weight management and type 2 diabetes, GOV.UK, 2026. [Accessed 10th August 2026]