Orforglipron (Foundayo): Tablet Doses, Weight Loss, Side Effects and FDA Approval
The short answer
Orforglipron is Eli Lilly's once-daily GLP-1 pill, approved by the FDA on 1 April 2026 for weight management under the brand name Foundayo. It is a small molecule, not a peptide, and is taken with or without food. Doses start at 0.8 mg and step up monthly to at most 17.2 mg. At the top dose people without diabetes lost 11.1% of body weight in 72 weeks, against 2.1% on placebo.
Orforglipron is Eli Lilly's once-a-day GLP-1 pill, approved by the FDA on 1 April 2026 and sold as Foundayo. Lilly calls it the only GLP-1 pill for weight loss that can be taken any time of day without food or water restrictions, and despite the "peptide" tag some sellers give it, it is a small molecule, not a peptide. Everything below is from the US label (revised July 2026), the FDA approval letter and the published phase 3 trials.
What Foundayo (orforglipron) is
Foundayo is the brand name; orforglipron is the drug. It binds to and switches on the GLP-1 receptor, the same target as semaglutide and the GLP-1 half of tirzepatide (Foundayo label). The difference is the molecule: the ATTAIN-1 trial paper calls it "a small-molecule, nonpeptide oral glucagon-like peptide-1 (GLP-1) receptor agonist" (ATTAIN-1, NEJM 2025). That is why it survives the stomach without the strict empty-stomach routine of oral semaglutide.
It was discovered by Chugai Pharmaceutical as OWL833 and licensed to Lilly in September 2018, with Lilly taking worldwide rights (Chugai release). The label gives the half-life as about 29 to 49 hours and the time to peak as 4 to 8 hours, which is what makes once a day work.
FDA approval
- Approved 1 April 2026, NDA 220934, a new molecular entity, received on 20 January 2026 (FDA approval letter, Drugs@FDA).
- Fast. It was the first new molecular entity approved under the Commissioner's National Priority Voucher pilot, "Issued 50 days after filing" (FDA announcement).
- What for. With a reduced calorie diet and more activity, to reduce excess body weight and keep it off long term, in adults with obesity, or overweight with at least one weight-related condition. The label says it should not be combined with another GLP-1 drug.
- Not approved for type 2 diabetes. The only indication is weight management. Lilly has run the ACHIEVE diabetes trials; as of its 30 September 2026 release it described orforglipron as "being studied" for type 2 diabetes. Outside the US, the UK's MHRA authorised it on 10 August 2026, though it is not yet available on the NHS (MHRA), and the EMA recommended EU authorisation on 16 October 2026 (EMA); Lilly says it has filed in more than 40 countries (Lilly, 1 April 2026).
Foundayo dosage: tablet strengths and the monthly steps
Foundayo comes in six tablet strengths: 0.8, 2.5, 5.5, 9, 14.5 and 17.2 mg, in bottles of 30. The label starts everyone low and steps up no faster than every 30 days:
| When | Dose | Label rule |
|---|---|---|
| Month 1 | 0.8 mg once a day | Starting dose |
| Month 2 | 2.5 mg once a day | After at least 30 days on 0.8 mg |
| Month 3 | 5.5 mg once a day | After at least 30 days on 2.5 mg; a dose tested in the trials |
| Month 4 on, if needed | 9 mg, then 14.5 mg, then 17.2 mg | Each step after at least 30 days, by response and tolerability; 17.2 mg is the maximum |
How to take it, per the label: one tablet a day, "with or without food", swallowed whole, not broken, crushed or chewed, and never more than one a day. A missed dose is taken as soon as possible without doubling up, but after 7 or more missed days in a row the escalation restarts at a lower dose. With a strong CYP3A4 inhibitor (clarithromycin raised exposure 3.5 times) the maximum is 9 mg. The tablets are stored at room temperature, 20 to 25°C, so unlike the injectable pens there is no fridge.
Orforglipron weight loss: the trial results
The label reports the two 72-week weight trials at the marketed tablet doses. The journal papers report the same trials as 6, 12 and 36 mg of the trial formulation, which line up with the 5.5, 9 and 17.2 mg tablets (the label calls them "equivalent dosages").
| Measure | Placebo | 5.5 mg | 9 mg | 17.2 mg |
|---|---|---|---|---|
| Trial 1 (ATTAIN-1): obesity or overweight, no diabetes, 72 weeks | -2.1% | -7.4% | -8.3% | -11.1% |
| Trial 2 (ATTAIN-2): obesity or overweight with type 2 diabetes, 72 weeks | -2.5% | -5.1% | -7.0% | -9.6% |
| Trial 1: share who lost at least 10% | 13% | 32.5% | 39.8% | 54.5% |
| Trial 1: share who lost at least 15% | 6% | 14.3% | 20.1% | 35.9% |
In plain numbers, the top dose took off about 11% of body weight in people without diabetes, against 2% on placebo (ATTAIN-1), and close to 10% in people with type 2 diabetes (ATTAIN-2, Lancet). After people had lost weight on tirzepatide, switching to orforglipron kept an estimated 74.7% of the loss at a year, against 49.2% on placebo (ATTAIN-MAINTAIN, Nat Med).
Foundayo side effects
The label's table pools the two weight trials (3,155 people on Foundayo, 1,576 on placebo). Stomach and gut effects dominate, are most common while the dose is going up, and fade over time; 60% were mild and 4% severe.
| Side effect | Placebo | 5.5 mg | 9 mg | 17.2 mg |
|---|---|---|---|---|
| Nausea | 10% | 26% | 34% | 35% |
| Constipation | 9% | 20% | 27% | 24% |
| Diarrhoea | 11% | 21% | 23% | 25% |
| Vomiting | 4% | 13% | 21% | 24% |
| Indigestion (dyspepsia) | 4% | 12% | 16% | 13% |
| Abdominal pain | 7% | 13% | 14% | 14% |
| Headache | 7% | 8% | 9% | 9% |
| Fatigue | 4% | 6% | 7% | 9% |
| Burping | 1% | 6% | 8% | 8% |
| Hair loss | 2% | 4% | 4% | 5% |
| Stopped because of side effects | 3% | 6% | 9% | 10% |
- Boxed warning: risk of thyroid C-cell tumours, as for every GLP-1 drug. The label notes orforglipron "is not pharmacologically active in rats or mice and did not produce tumors in rodents", and it is still not for anyone with a personal or family history of medullary thyroid cancer or MEN 2.
- Other label warnings: pancreatitis, severe stomach reactions, kidney injury from dehydration, low blood sugar with insulin or sulfonylureas, allergic reactions, diabetic eye complications, gallbladder disease, and aspiration under anaesthesia.
- Also in the label data: a faster heart rate in 3% vs 0.9% on placebo, and hair loss in 7% of women on Foundayo.
- The pill and the pill. Oral contraceptives may work less well: the label says to switch to a non-oral method or add a barrier method for 30 days after starting and after each dose step.
- Pregnancy: stop when a pregnancy is recognised; not recommended while breastfeeding.
Orforglipron vs semaglutide
The only head-to-head trial is in type 2 diabetes. In ACHIEVE-3, over 52 weeks, orforglipron 12 mg and 36 mg lowered A1C by 1.71 and 1.91 points, against 1.23 and 1.47 for oral semaglutide 7 mg and 14 mg; more people stopped orforglipron for side effects, 9% and 10% against 4% and 5% (ACHIEVE-3, Lancet). For weight loss there is no head-to-head trial. One indirect comparison of the obesity trials found oral semaglutide 25 mg took off 3.2 points more than orforglipron 36 mg (Diabetes Obes Metab 2026); indirect comparisons are weak evidence either way. The practical difference is the routine: oral semaglutide is taken on an empty stomach with a little water and a wait before eating, Foundayo any time.
"Research" orforglipron
Orforglipron is approved only as Foundayo, from one company, Eli Lilly. Powders or capsules sold as research orforglipron are not that product and have had no FDA review. The FDA's general warning on unapproved GLP-1 drugs covers products "falsely labeled 'for research purposes' or 'not for human consumption'" (FDA). We list no vendor for it.
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Build your stack, 2 minutesFrequently asked questions
What is Foundayo?
Foundayo is the brand name of orforglipron, a once-daily GLP-1 receptor agonist pill from Eli Lilly. The FDA approved it on 1 April 2026 to help adults with obesity, or overweight with a weight-related condition, lose weight and keep it off, alongside diet and exercise.
Is orforglipron FDA approved?
Yes. The FDA approved orforglipron as Foundayo on 1 April 2026 (NDA 220934) for chronic weight management, 50 days after filing under the National Priority Voucher pilot. In the US it is not approved for type 2 diabetes. The UK authorised it on 10 August 2026.
Is orforglipron a peptide?
No. Unlike semaglutide and tirzepatide, orforglipron is a small, non-peptide molecule that activates the GLP-1 receptor. That is why it can be taken as a pill without the empty-stomach routine of oral semaglutide.
What doses does Foundayo come in?
Six tablets: 0.8, 2.5, 5.5, 9, 14.5 and 17.2 mg. The label starts at 0.8 mg once daily and steps up after at least 30 days on each dose, to a maximum of 17.2 mg once daily.
What are the side effects of orforglipron?
Mostly stomach and gut effects. At 17.2 mg in the label data: nausea 35% vs 10% on placebo, diarrhoea 25%, vomiting 24% and constipation 24%. 10% stopped because of side effects at that dose, against 3% on placebo. It carries the GLP-1 boxed warning on thyroid C-cell tumours.
How much weight do you lose on Foundayo?
In the 72-week ATTAIN-1 trial in people without diabetes, the 17.2 mg dose took off 11.1% of body weight on average, against 2.1% on placebo, and 54.5% of people lost at least 10%. In people with type 2 diabetes the top dose took off 9.6%.
Do you take Foundayo with food?
It can be taken with or without food, once a day, swallowed whole. The label sets no water limit or waiting time, unlike oral semaglutide.
Sources (checked 8 November 2026)
- Foundayo (orforglipron) tablets, US prescribing information, Eli Lilly, revised 7/2026. Checked 8 November 2026.
- Foundayo prescribing information and Medication Guide, FDA-hosted label, revised 07/2026. Checked 8 November 2026.
- FDA approval letter, NDA 220934, 1 April 2026. Checked 8 November 2026.
- Drugs@FDA, NDA 220934, Foundayo. Checked 8 November 2026.
- FDA approves first new molecular entity under National Priority Voucher program, FDA, 1 April 2026. Checked 8 November 2026.
- FDA approves Lilly's Foundayo (orforglipron), Eli Lilly release, 1 April 2026. Checked 8 November 2026.
- Orforglipron, an oral small-molecule GLP-1 receptor agonist for obesity treatment (ATTAIN-1). N Engl J Med 2025;393(18):1796-1806. Checked 8 November 2026.
- Orforglipron for obesity in people with type 2 diabetes (ATTAIN-2). Lancet 2026;406(10522):2927-2944. Checked 8 November 2026.
- Orforglipron, an oral small-molecule GLP-1 receptor agonist, in early type 2 diabetes (ACHIEVE-1). N Engl J Med 2025;393(11):1065-1076. Checked 8 November 2026.
- Once-daily oral orforglipron compared with oral semaglutide in adults with type 2 diabetes (ACHIEVE-3). Lancet 2026;407(10534):1147-1160. Checked 8 November 2026.
- Orforglipron for weight maintenance after tirzepatide or semaglutide (ATTAIN-MAINTAIN). Nat Med 2026;32(7):2679-2687. Checked 8 November 2026.
- Cardiovascular safety of orforglipron vs insulin glargine (ACHIEVE-4). Lancet 2026;408(10564):1557-1570. Checked 8 November 2026.
- Indirect comparison of oral semaglutide 25 mg and orforglipron 36 mg (OASIS 4 vs ATTAIN-1). Diabetes Obes Metab 2026. Checked 8 November 2026.
- Chugai and Lilly licence agreement for OWL833, Chugai release, 27 September 2018. Checked 8 November 2026.
- FDA's concerns with unapproved GLP-1 drugs used for weight loss, FDA, content current as of 1 October 2026. Checked 8 November 2026.
- UK first in Europe to authorise orforglipron, MHRA, 10 August 2026. Checked 8 November 2026.
- New oral GLP-1 medicine for weight management and type 2 diabetes, EMA, 16 October 2026. Checked 8 November 2026.
Foundayo is a prescription medicine; figures are from the FDA label and the trials listed. Labels and trial records change; the leaflet in your box and your prescriber come first. Educational content, not medical advice.