What is Foundayo?
Foundayo is the brand name for orforglipron, a once-daily oral GLP-1 receptor agonist made by Eli Lilly.1
It belongs to the same class of medications as injectable Wegovy (semaglutide) and injectable Mounjaro (tirzepatide). All three reduce appetite and slow digestion by mimicking the hormone GLP-1.
Foundayo is different from other oral GLP-1s in two ways.
First, it’s a small molecule, not a peptide. Most GLP-1 medications (including semaglutide and tirzepatide) are peptides, which means they get broken down by stomach acid.
Foundayo’s small-molecule structure survives digestion intact, which is why it can be taken orally without special conditions.2
Second, it can be taken at any time of day, with or without food, with no water restrictions.1 The Wegovy pill (the other oral GLP-1 approved for weight loss) requires an empty stomach, no more than 120 ml of water, and a 30-minute fast after taking it.
Foundayo is available in six doses: 0.8 mg, 2.5 mg, 5.5 mg, 9 mg, 14.5 mg, and 17.2 mg. Treatment starts at the lowest dose and increases every 30 days based on how you respond and what side effects you experience.1
How effective is Foundayo?
The main evidence comes from the ATTAIN-1 trial, a 72-week, randomised, double-blind, placebo-controlled study published in the New England Journal of Medicine.2
The trial enrolled 3,127 adults living with obesity or overweight (with at least one weight-related condition) who didn’t have type 2 diabetes.
Participants were randomly assigned to receive orforglipron at 6 mg, 12 mg, or 36 mg, or placebo, alongside a healthy diet and physical activity.
Weight loss results by dose:
- 7.5% average weight loss with 6 mg (approximately 17 lbs)
- 8.4% with 12 mg (approximately 19 lbs)
- 11.2% with 36 mg (approximately 25 lbs)
- 2.1% with placebo (approximately 5 lbs)
Among participants on the 36 mg dose who remained on treatment for the full 72 weeks, the average weight loss was 12.4% (approximately 27 lbs).2
At the highest dose, 54.6% of participants lost at least 10% of their body weight, 36% lost at least 15%, and 18.4% lost 20% or more.2
The trial also found improvements in waist circumference, blood pressure, triglycerides, and non-HDL cholesterol across all doses.
A separate trial, ATTAIN-2, studied orforglipron in adults with type 2 diabetes and obesity.
At the highest dose, participants lost an average of 10.5% of their body weight over 72 weeks, alongside significant reductions in HbA1c of up to 1.8%.3
It’s worth noting that the ATTAIN-1 trial tested doses up to 36 mg in a capsule formulation, but the approved Foundayo tablet doses go up to 17.2 mg.
The prescribing label reports weight loss of 7.4% to 11.1% across the approved tablet doses, which is slightly lower than the 36 mg capsule results.1
How orforglipron works
Orforglipron activates GLP-1 receptors, the same targets as injectable Wegovy and the Wegovy pill. GLP-1 is a hormone your body naturally produces after eating.
It signals to your brain that you’re full, slows the rate at which food leaves your stomach, and helps regulate blood sugar.2
By activating these receptors with a medication, appetite is reduced, you feel full sooner, and you eat less overall. Over time, this creates a sustained calorie deficit that leads to weight loss.
The difference between orforglipron and semaglutide (Wegovy) is structural. Semaglutide is a modified version of the natural GLP-1 hormone. It’s a peptide, and peptides are normally destroyed by stomach acid.
Novo Nordisk solved this for the Wegovy pill by adding an absorption enhancer (SNAC) that protects the drug in the stomach.4 Even with SNAC, the tablet needs strict fasting conditions to be absorbed properly.
Orforglipron was designed as a small molecule, not a peptide. It doesn’t need protection from stomach acid because it isn’t broken down by digestive enzymes. This is why it can be taken with food, at any time of day, without fasting.2
Orforglipron mimics the hormone GLP-1, not GIP. Injectable Mounjaro (tirzepatide) mimics both GLP-1 and GIP, which is one reason Mounjaro produces greater weight loss.
Foundayo’s function of mimicking only GLP-1 partly explains why its weight-loss figures are lower than those of injectable Mounjaro.
How to take Foundayo
Foundayo is taken as one tablet once a day. There are no restrictions on when you take it or whether you’ve eaten.1
Swallow the tablet whole. Don’t crush, break, or chew it.
If you miss a dose, take it as soon as you remember on the same day. Don’t take more than one tablet per day.
The tablets can be stored at room temperature, so there’s no need for refrigeration.1
Treatment follows a dose escalation schedule:
- Start at 0.8 mg once daily
- Increase to 2.5 mg after at least 30 days
- Increase to 5.5 mg after at least 30 days
- Further increases to 9 mg, 14.5 mg, or 17.2 mg are possible based on how you respond and what side effects you experience
Not everyone will need to reach the highest dose. Your prescriber will adjust based on your weight loss progress and how well you tolerate the medication.
How Foundayo compares to other GLP-1 medications
|
Foundayo |
Wegovy pill |
Injectable Wegovy (2.4 mg) |
Injectable Mounjaro (15 mg) |
| Drug |
Orforglipron |
Semaglutide |
Semaglutide |
Tirzepatide |
| Drug class |
GLP-1 agonist (small molecule) |
GLP-1 agonist (peptide) |
GLP-1 agonist (peptide) |
Dual GIP/GLP-1 agonist (peptide) |
| How you take it |
Daily tablet, any time, no restrictions |
Daily tablet, empty stomach, 30-min fast |
Weekly injection |
Weekly injection |
| Average weight loss |
11.2% at 72 weeks (ATTAIN-1)2 |
13.6% at 64 weeks (OASIS 4)5 |
14.9% at 68 weeks (STEP 1)6 |
22.5% at 72 weeks (SURMOUNT-1)7 |
| Storage |
Room temperature |
Room temperature |
Refrigerated |
Refrigerated |
| UK availability |
Not yet approved |
Expected late 2026 |
Available now |
Available now |
Injectable Mounjaro produces the greatest weight loss of any currently available GLP-1 medication. Injectable Wegovy sits between Mounjaro and the oral options.
Foundayo produces less weight loss than the Wegovy pill (11.2% vs 13.6%), but it’s much easier to take.
If adherence is a concern, the convenience of taking a pill at any time without fasting may lead to more consistent use in practice.
For people currently in the UK, injectable Mounjaro and injectable Wegovy remain the only available GLP-1 options for weight loss. The Wegovy pill is expected by late 2026, with Foundayo likely to follow.
Side effects of Foundayo
Side effects are consistent with the broader GLP-1 medication class. The most common in the ATTAIN trials were:2
- Nausea
- Constipation
- Diarrhoea
- Vomiting
- Indigestion
- Abdominal pain
These side effects occurred most frequently during the dose escalation phase and were generally rated as mild to moderate.
Hair loss is also listed as a common side effect of Foundayo.1 This wasn’t a prominent finding in injectable GLP-1 trials, though it has been reported anecdotally by some people taking other weight-loss medications.
Treatment discontinuation due to adverse events ranged from 5.3% to 10.3% across orforglipron dose groups in ATTAIN-1, compared to 2.7% with placebo.2
Foundayo carries a boxed warning regarding thyroid C-cell tumours observed in animal studies, consistent with other GLP-1 medications.
This risk has not been confirmed in humans, but the medication is not recommended for anyone with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2.1
When will Foundayo be available in the UK?
Foundayo launched in the U.S. on 6 April 2026. It’s currently only available in the US.
Eli Lilly has indicated that global regulatory submissions are underway, but no specific timeline for MHRA review or UK approval has been confirmed.1
Based on typical regulatory pathways, UK approval could follow 12 to 18 months after the U.S. approval. Although this may be sooner, given how quickly it was approved in the U.S.
If the MHRA follows a similar timeline to other recent GLP-1 approvals, private providers could offer Foundayo in the UK by 2027, with NHS access depending on a subsequent NICE health technology assessment.
The Wegovy pill (oral semaglutide) is expected to reach the UK sooner, with approval anticipated in late 2026. If you want an oral GLP-1 option as soon as possible, the Wegovy pill is likely to be the first available in the UK.
In the meantime, injectable Mounjaro and injectable Wegovy are both available in the UK through private providers and, in some cases, through the NHS.
Using Foundayo for weight maintenance after injectable treatment
One of the most clinically useful findings from the ATTAIN programme is the ATTAIN-MAINTAIN trial, which tested whether people who had already lost weight on injectable GLP-1s could switch to oral orforglipron for long-term maintenance.8
Participants who had reached a weight plateau on injectable Wegovy or Mounjaro were re-randomised to receive either orforglipron or placebo for 52 weeks.
Those who switched from Wegovy to orforglipron regained an average of just 0.9 kg over 52 weeks, maintaining nearly all of their previous weight loss.8
These results suggest a potential treatment model that didn’t previously exist: lose weight on the most effective injectable option, then transition to a convenient daily pill for maintenance.
For people who don’t want to stay on injections indefinitely, this could offer a practical alternative to either continuing injections or stopping treatment entirely and risking weight regain.
Whether this maintenance effect holds beyond 52 weeks is still unknown. The ATTAIN-MAINTAIN trial was relatively small (376 participants) and will need longer follow-up to confirm durability.
Frequently asked questions
What is Foundayo?
Foundayo is the brand name for orforglipron, a once-daily oral GLP-1 weight-loss medication made by Eli Lilly. It was approved by the FDA on 1 April 2026.1
Is Foundayo available in the UK?
Not yet. Foundayo is currently only available in the U.S. Eli Lilly has indicated global regulatory submissions are underway, but no UK timeline has been confirmed. UK approval could follow in late 2027 based on typical regulatory pathways.
How much weight can you lose on Foundayo?
In the ATTAIN-1 trial, people on the highest dose lost an average of 11.2% of their body weight (approximately 25 lbs) over 72 weeks. Among those who adhered to treatment throughout, average weight loss was 12.4%.2
How do you take Foundayo?
One tablet once a day, at any time, with or without food. No water restrictions. Swallow whole. If you miss a dose, take it the same day when you remember.1
What are the side effects of Foundayo?
The most common side effects are nausea, constipation, diarrhoea, vomiting, indigestion, and abdominal pain. Hair loss is also listed as a common side effect. Most side effects are mild to moderate and occur during dose escalation.2
Is Foundayo the same as Mounjaro?
No. Foundayo contains orforglipron (a GLP-1 agonist). Mounjaro contains tirzepatide (a dual GIP/GLP-1 agonist).
Both are made by Eli Lilly, but they’re different medications with different mechanisms. Mounjaro produces greater weight loss but requires weekly injections.
How much does Foundayo cost?
In the U.S., the starting dose costs $149 per month for self-pay patients through LillyDirect. With eligible commercial insurance, the cost may be as low as $25 per month with a savings card.3 UK pricing hasn’t been confirmed.
Foundayo vs Wegovy pill: which is better?
The Wegovy pill produces slightly more weight loss (13.6% vs 11.2%), but Foundayo is easier to take because it has no fasting or timing restrictions.25 Neither is available in the UK yet. The Wegovy pill is expected first (late 2026), with Foundayo likely to follow.
Can you switch from Mounjaro or Wegovy injections to Foundayo?
The ATTAIN-MAINTAIN trial found that people who switched from injectable Wegovy or Mounjaro to orforglipron maintained nearly all of their weight loss over 52 weeks.8 This would need to be discussed with your prescriber, as the medications work through different mechanisms and dosing schedules.
Is orforglipron a peptide?
No. Orforglipron is a small molecule, not a peptide. This is why it can be taken orally without the fasting requirements that peptide-based oral GLP-1s (like the Wegovy pill) need.2
What is the brand name for orforglipron?
Foundayo. It’s made by Eli Lilly and was approved by the FDA on 1 April 2026.1
When will a GLP-1 weight-loss pill be available in the UK?
The Wegovy pill (oral semaglutide) is expected to receive UK approval in late 2026 and will likely be the first oral GLP-1 weight-loss option available here.
Foundayo could follow in late 2027 (potentially earlier). Both would need NICE approval before becoming available on the NHS.
Take home message
Foundayo is the first oral GLP-1 medication that can be taken without fasting, timing, or water restrictions.
It produces meaningful weight loss (11.2% over 72 weeks at the highest dose), though less than injectable Mounjaro or Wegovy.
For people who have avoided GLP-1 treatment because of needles or the dosing requirements of the Wegovy pill, Foundayo removes both barriers.
It’s not yet available in the UK. The Wegovy pill is expected to arrive first (late 2026), with Foundayo likely to follow.
In the meantime, injectable Mounjaro and Wegovy are both available from private providers and, in some cases, through the NHS.
The ATTAIN-MAINTAIN trial data suggest that Foundayo could also serve as a maintenance option for people who have already lost weight on injectable GLP-1s, though longer-term data are needed.
Whichever medication or format you choose, the evidence consistently shows that combining GLP-1 treatment with structured behaviour change support produces better long-term results.
Second Nature’s published research found that members taking semaglutide alongside dietitian-led support achieved an average of 19.1% weight loss at 12 months.9
Second Nature's Mounjaro and Wegovy programmes
Second Nature provides Mounjaro or Wegovy as part of our Mounjaro and Wegovy weight-loss programmes.
Why choose Second Nature over other medication providers, assuming you're eligible?
Because peace of mind matters.
We've had the privilege of working with the NHS for over eight years, helping people across the UK take meaningful steps toward a healthier, happier life.
Our programmes are designed to meet people where they are, whether that means support with weight loss through compassionate one-to-one health coaching, or access to the latest weight-loss medications (like Mounjaro and Wegovy) delivered alongside expert care from a multidisciplinary team of doctors, psychologists, dietitians, and personal trainers.
At the heart of everything we do is a simple belief: real, lasting change comes from building better habits, not relying on quick fixes. We're here to support that change every step of the way.
With over a decade of experience, thousands of lives changed, and a long-standing record of delivering programmes used by the NHS, we believe we're the UK's most trusted weight-loss programme.
We hope to offer you something invaluable: peace of mind, and the support you need to take that first step.
References
- US Food and Drug Administration. (2026). FDA approves first new molecular entity under National Priority Voucher program. Press release, 1 April 2026.
- Wharton, S., et al. (2025). Orforglipron, an oral small-molecule GLP-1 receptor agonist, for obesity treatment. New England Journal of Medicine.
- Eli Lilly. (2026). 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. Press release, 1 April 2026.
- Buckley, S.T., et al. (2018). Transcellular stomach absorption of a derivatized glucagon-like peptide-1 receptor agonist. Science Translational Medicine, 10(467).
- Wharton, S., et al. (2025). Oral semaglutide at a dose of 25 mg in adults with overweight or obesity. New England Journal of Medicine, 393(11).
- Wilding, J.P., et al. (2021). Once-weekly semaglutide in adults with overweight or obesity. New England Journal of Medicine, 384(11), 989-1002.
- Jastreboff, A.M., et al. (2022). Tirzepatide once weekly for the treatment of obesity. New England Journal of Medicine, 387(3), 205-216.
- Eli Lilly. (2025). Lilly’s orforglipron helped people maintain weight loss after switching from injectable incretins to oral GLP-1 therapy. Press release, 18 December 2025.
- Richards, R., et al. (2025). A remotely delivered, semaglutide-supported specialist weight management program: 12-month outcomes. JMIR Formative Research, 9(1), e72577.
