Key facts
- Orforglipron is a once-daily oral, small-molecule (non-peptide) GLP-1 receptor agonist. Chugai Pharmaceutical discovered it, and Eli Lilly licensed it in 2018.[4]
- The FDA approved it as Foundayo on 1 April 2026 for weight management in adults with obesity, or overweight plus at least one weight-related condition.[1][2]
- In the 72-week ATTAIN-1 trial, people without diabetes lost 11.2% on the top dose against 2.1% on placebo, or 12.4% had everyone stayed on treatment.[8][4]
- In ACHIEVE-3, the top dose cut HbA1c by 1.91 points against 1.47 points for oral semaglutide 14 mg, the first head-to-head phase 3 trial of two oral GLP-1 drugs.[13][6]
- Lilly submitted orforglipron for type 2 diabetes in the US in Q2 2026. As of November 2026 the US label covers weight management only.[7][3]
What Is Orforglipron?
Orforglipron is a once-daily GLP-1 receptor agonist taken as a tablet, sold in the US as Foundayo in six strengths from 0.8 mg to 17.2 mg since its FDA approval on 1 April 2026.[3][1]
| Feature | Orforglipron |
|---|---|
| Developer | Eli Lilly; discovered by Chugai Pharmaceutical, licensed to Lilly in 2018[4] |
| Brand name | Foundayo (US)[1] |
| Drug class | GLP-1 receptor agonist[3] |
| Structure | Small molecule, non-peptide; supplied as orforglipron calcium (molecular weight 902.0 g/mol)[3][8] |
| Route and frequency | Oral tablet, once daily, with or without food[3] |
| Half-life | About 29 to 49 hours[3] |
| Tablet strengths | 0.8, 2.5, 5.5, 9, 14.5 and 17.2 mg[3] |
| Best phase 3 weight loss | -11.2% at 72 wk (ATTAIN-1, top dose, treatment-regimen estimand)[8] |
| US approval | 1 April 2026, weight management (NDA 220934)[1][2] |
| Type 2 diabetes | Submitted to the FDA in Q2 2026; not on the US label as of Nov 2026[7][3] |
Orforglipron is not sold in this shop, and this page is not a guide to obtaining it. It summarises published research and regulatory records for reference.
How Orforglipron Works
Orforglipron binds to and activates the human GLP-1 receptor; as a small molecule rather than a peptide it is taken by mouth, with an absolute oral bioavailability of 77% after a 0.8 mg dose and no clinically relevant food effect.[3][8]
- It is not a peptide. Semaglutide, tirzepatide and eloralintide are all peptides. Orforglipron is a small, non-peptide molecule designed to be taken by mouth once a day.[8][13]
- No food or water restrictions. The label says to take it once daily with or without food, and Lilly describes it as a pill that can be taken at any time of day without restrictions on food and water intake.[3][4] In a food-effect study, food lowered exposure (AUC) by 19%, which the label calls not clinically relevant.[3]
- It acts on appetite. GLP-1 receptors sit in brain regions that regulate appetite. The label says orforglipron decreases food intake, likely by decreasing appetite, and that weight loss involves more fat mass than lean mass.[3]
- It slows stomach emptying. The delay is largest after the first dose and fades over time, which can affect how other oral medicines are absorbed.[3]
- It is cleared by the liver. Steady state is reached after about 1 week of daily dosing; the drug is broken down mainly by CYP3A4, and 87% of a dose is recovered in faeces.[3]
One unusual label detail: orforglipron is not pharmacologically active in rats or mice and did not cause thyroid tumours in rodents, but the label still carries the class boxed warning on thyroid C-cell tumours because the human relevance is not established.[3]
Orforglipron Weight Loss Results (ATTAIN-1, ATTAIN-2)
In ATTAIN-1, 3,127 adults with obesity and no diabetes lost 7.5% to 11.2% of body weight over 72 weeks depending on dose, against 2.1% on placebo.[8]
Treatment-regimen estimand (regardless of stopping), NEJM abstract. Trial doses as published; the label lists them as 5.5 mg, 9 mg and 17.2 mg tablets.
| Trial | Population | Orforglipron | Placebo |
|---|---|---|---|
| ATTAIN-1 (n = 3,127) | Obesity or overweight, no diabetes | -7.5% (6 mg), -8.4% (12 mg), -11.2% (36 mg); -12.4% top dose, efficacy estimand | -2.1%; -0.9% efficacy[8][4] |
| ATTAIN-2 (n = 1,613) | Obesity or overweight with type 2 diabetes | -5.1% (6 mg), -7.0% (12 mg), -9.6% (36 mg) | -2.5%[9] |
- On the top ATTAIN-1 dose, 54.6% lost at least 10% of body weight, 36.0% at least 15% and 18.4% at least 20%, against 12.9%, 5.9% and 2.8% on placebo.[8]
- Lilly reports that people on the highest dose who stayed on treatment lost an average of 27.3 lb (12.4%), against 2.2 lb (0.9%) on placebo.[4]
- Waist size, systolic blood pressure, triglycerides and non-HDL cholesterol all improved against placebo in ATTAIN-1.[8]
- In the 36-week phase 2 obesity trial (272 adults, doses 12 to 45 mg), weight fell by 9.4% to 14.7% against 2.3% on placebo.[15]
- In ATTAIN-MAINTAIN, people who had reached a weight plateau on tirzepatide or semaglutide and then switched kept 74.7% and 79.3% of their earlier weight loss at 52 weeks on orforglipron, against 49.2% and 37.6% on placebo.[10]
Orforglipron in Type 2 Diabetes (ACHIEVE Trials)
In ACHIEVE-1, orforglipron lowered HbA1c by 1.24 to 1.48 percentage points over 40 weeks from a baseline of 8.0%, against 0.41 points on placebo.[11]
| Trial | Comparator | Length | Orforglipron | Comparator result |
|---|---|---|---|---|
| ACHIEVE-1 (n = 559) | Placebo | 40 wk | -1.24 (3 mg), -1.47 (12 mg), -1.48 (36 mg) | -0.41[11] |
| ACHIEVE-2 (n = 962) | Dapagliflozin 10 mg | 40 wk | -1.23 (3 mg), -1.50 (12 mg), -1.56 (36 mg) | -0.81[12] |
| ACHIEVE-3 (n = 1,698) | Oral semaglutide 7 mg or 14 mg | 52 wk | -1.71 (12 mg), -1.91 (36 mg) | -1.23 (7 mg), -1.47 (14 mg)[13] |
| ACHIEVE-4 (n = 2,749) | Insulin glargine | 52 wk (median follow-up 2 years) | -1.6, efficacy estimand | -1.0[5][14] |
- Weight also fell in ACHIEVE-1: 4.5% (3 mg), 5.8% (12 mg) and 7.6% (36 mg) at 40 weeks, against 1.7% on placebo.[11]
- In ACHIEVE-3, both orforglipron doses were superior to both oral semaglutide doses on HbA1c, including 12 mg against semaglutide 14 mg.[13] Lilly reports weight loss of 9.2% on the top dose against 5.3% on oral semaglutide 14 mg (efficacy estimand).[6]
- ACHIEVE-4 met its cardiovascular safety goal: major adverse cardiovascular events (MACE-4) occurred in 4.2% on orforglipron against 5.0% on insulin glargine (hazard ratio 0.84, 95% CI 0.59 to 1.20).[14]
- Deaths in ACHIEVE-4 were 1.4% on orforglipron against 3.2% on insulin glargine; Lilly notes the all-cause death analysis was not controlled for multiplicity.[14][5]
- In the earlier 26-week phase 2 diabetes trial, HbA1c fell by up to 2.10 points against 0.43 on placebo and 1.10 on dulaglutide.[16]
Orforglipron Doses in Trials
The phase 3 trials tested once-daily doses of 3 mg to 36 mg of an investigational capsule, which the FDA label expresses as tablet doses of 0.8 mg to 17.2 mg (36 mg capsule = 17.2 mg tablet).[8][14][3]
| Trial | Doses as published (once daily) | Label tablet equivalent | Length |
|---|---|---|---|
| Phase 2 obesity (n = 272) | 12, 24, 36 or 45 mg | Not stated[15] | 36 weeks |
| Phase 2 type 2 diabetes (n = 383) | 3, 12, 24, 36 or 45 mg; two escalation schemes for 36 and 45 mg | Not stated[16] | 26 weeks |
| ATTAIN-1 and ATTAIN-2 | 6, 12 or 36 mg | 5.5, 9 or 17.2 mg[8][9][3] | 72 weeks |
| ACHIEVE-1 and ACHIEVE-2 | 3, 12 or 36 mg | 2.5, 9 or 17.2 mg (ACHIEVE-2)[11][6] | 40 weeks |
| ACHIEVE-3 | 12 or 36 mg | 9 or 17.2 mg[13][6] | 52 weeks |
| ACHIEVE-4 | Started at 1 mg, raised every 4 weeks to the maximum tolerated dose, up to 36 mg | 0.8 mg start, up to 17.2 mg[5] | Event-driven |
The label explains that the pivotal trials used an investigational orforglipron formulation and presents the results as equivalent doses of the marketed tablet.[3] In ATTAIN-1 and ATTAIN-2, doses were raised in steps of at least 30 days, starting from the lowest strength, as set out in the label.[3]
Orforglipron Side Effects
Gastrointestinal side effects affected 60% to 69% of people on orforglipron in the pooled ATTAIN trials against 37% on placebo, and 8% stopped treatment because of adverse reactions (placebo 3%).[3]
| Adverse reaction | 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% |
| Stopped due to GI reactions | 0.7% | 3% | 6% | 6%[3] |
- Of those with GI reactions, 60% were mild, 36% moderate and 4% severe; nausea, vomiting and diarrhoea were most common during dose escalation and eased over time.[3]
- Other common reactions on the label include headache, abdominal pain, bloating, fatigue, belching, reflux, flatulence and hair loss.[3]
- Heart rate rose by a mean of 4 to 5 beats per minute against 0.5 on placebo, and tachycardia was reported in 3% against 0.9%.[3]
- Acute pancreatitis was confirmed in 6 people on orforglipron (0.14 per 100 patient-years) against 1 on placebo (0.04).[3]
- The label carries a boxed warning on thyroid C-cell tumours and warnings on pancreatitis, severe GI reactions, kidney injury from dehydration, low blood sugar with insulin or sulfonylureas, gallbladder disease and aspiration during anaesthesia.[3]
In ACHIEVE-3, GI events were more common on orforglipron (58% to 59%) than on oral semaglutide (37% to 45%), and more people stopped orforglipron because of adverse events (9% to 10% against 4% to 5%).[13]
Is Orforglipron FDA Approved?
Yes. The FDA approved orforglipron as Foundayo on 1 April 2026 for weight management, after receiving Lilly’s application on 20 January 2026; type 2 diabetes is not yet an approved US use.[1][2][3]
| Date | Event |
|---|---|
| 20 Jan 2026 | FDA receives the new drug application (NDA 220934)[1] |
| 1 Apr 2026 | FDA approves Foundayo for chronic weight management, as a new molecular entity[1][2] |
| 6 Apr 2026 | Shipping begins via LillyDirect, followed by US retail pharmacies and telehealth providers[4] |
| Q2 2026 | Lilly submits orforglipron for type 2 diabetes in the US[7] |
| 4 Aug 2026 | FDA approves a labelling and Medication Guide update (supplement 3)[2] |
- The approved use is to reduce excess body weight and keep it off long term in adults with obesity, or overweight plus at least one weight-related condition, alongside a reduced-calorie diet and more physical activity.[1]
- The application was not referred to an FDA advisory committee.[1]
- Lilly said it would file the type 2 diabetes application under the Commissioner’s National Priority Review Voucher.[5] Its Q2 2026 report confirmed the US submission had been made.[7]
- Lilly says it has submitted orforglipron for weight management and/or type 2 diabetes in more than 40 countries.[4]
- At US launch, Lilly stated a self-pay price starting at $149 a month for the lowest dose, as little as $25 a month with commercial insurance and a savings card, and $50 a month for eligible Medicare Part D patients from as soon as 1 July 2026.[4]
Orforglipron vs Eloralintide
Both come from Eli Lilly, but orforglipron is a daily GLP-1 pill that gave 11.2% weight loss at 72 weeks in phase 3, while eloralintide is a weekly amylin injection that gave up to 20.1% at 48 weeks in phase 2.[8][17]
| Feature | Orforglipron | Eloralintide |
|---|---|---|
| Developer | Eli Lilly (from Chugai)[4] | Eli Lilly[17] |
| Hormone target | GLP-1 receptor[3] | Amylin receptors, about 12 times more potent at AMY1 than at the calcitonin receptor[19] |
| Molecule | Small molecule, non-peptide[8] | Peptide with a C20 fatty diacid[19] |
| How it is taken | Tablet by mouth, once daily[3] | Injection under the skin, once weekly[18] |
| Best weight loss so far | -11.2% at 72 wk, phase 3 (treatment-regimen)[8] | -20.1% at 48 wk, phase 2 (9 mg, efficacy estimand)[17] |
| Stage | Phase 3 complete, ATTAIN and ACHIEVE[8][14] | Phase 3 ENLIGHTEN running[20] |
| Status | FDA approved as Foundayo, 1 Apr 2026[1] | Investigational, not approved[21] |
The two work on different hormone systems: orforglipron copies GLP-1, the gut hormone behind semaglutide and part of tirzepatide, while eloralintide copies amylin, a hormone released with insulin.[3][19] For the full eloralintide profile see what is eloralintide, and for other approaches see GLP-1 alternatives.
For how eloralintide compares with the injectable incretins, see eloralintide vs semaglutide and eloralintide vs tirzepatide. For context only, semaglutide 2.4 mg gave 14.9% weight loss at 68 weeks in STEP 1 and tirzepatide 15 mg gave 20.9% at 72 weeks in SURMOUNT-1, both separate trials.[22][23]
Frequently Asked Questions
Is orforglipron FDA approved?
Yes. The FDA approved orforglipron as Foundayo on 1 April 2026 for weight management in adults with obesity, or overweight with at least one weight-related condition. It is not yet approved in the US for type 2 diabetes; Lilly submitted that application in the second quarter of 2026.
What is the brand name of orforglipron?
Foundayo. Lilly gives the pronunciation as fown-DAY-oh. It is sold as once-daily tablets in strengths of 0.8 mg, 2.5 mg, 5.5 mg, 9 mg, 14.5 mg and 17.2 mg.
When will orforglipron be available?
In the US it already is. Lilly began shipping Foundayo through LillyDirect on 6 April 2026, followed by US retail pharmacies and telehealth providers. Lilly says it has submitted orforglipron in more than 40 countries and plans to launch in each shortly after approval.
How much weight can you lose on orforglipron?
In the 72-week ATTAIN-1 trial, people without diabetes lost an average of 11.2% of body weight on the highest dose, against 2.1% on placebo, or 12.4% (27.3 lb) among those who stayed on treatment. People with type 2 diabetes lost less: 9.6% on the highest dose in ATTAIN-2.
Is orforglipron better than Ozempic?
No published trial has compared orforglipron with injectable semaglutide (Ozempic or Wegovy). The only head-to-head trial is ACHIEVE-3 against oral semaglutide in type 2 diabetes, where orforglipron lowered HbA1c by up to 1.91 points against 1.47 for semaglutide 14 mg. In separate trials, injectable semaglutide 2.4 mg gave 14.9% weight loss in STEP 1, against 11.2% for orforglipron in ATTAIN-1, but the designs differ.
What are the side effects of orforglipron?
Mostly gastrointestinal: nausea, constipation, diarrhoea, vomiting and indigestion, usually mild to moderate and most common while the dose is being raised. In the pooled ATTAIN trials, GI reactions affected 60% to 69% of people on orforglipron against 37% on placebo, and the label carries a boxed warning on thyroid C-cell tumours.
Sources
- FDA. NDA 220934 approval letter, Foundayo (orforglipron) tablets, 1 Apr 2026
- FDA. Drugs@FDA, NDA 220934 (Foundayo) approval history
- FDA. FOUNDAYO (orforglipron) tablets prescribing information, revised 07/2026 (NDA 220934, supplement 3)
- Eli Lilly press release, 1 Apr 2026: FDA approves Foundayo (orforglipron)
- Eli Lilly press release, 16 Apr 2026: ACHIEVE-4 topline results
- Eli Lilly press release, 8 Jun 2026: ACHIEVE-2, ACHIEVE-3 and ACHIEVE-5 results (ADA 2026)
- Eli Lilly Q2 2026 results, 5 Aug 2026
- Wharton S, et al. Orforglipron, an oral small-molecule GLP-1 receptor agonist for obesity treatment (ATTAIN-1). N Engl J Med 2025;393(18):1796-1806. DOI 10.1056/NEJMoa2511774
- Horn DB, et al. Orforglipron for obesity in people with type 2 diabetes (ATTAIN-2). The Lancet 2025;406(10522):2927-2944. DOI 10.1016/S0140-6736(25)02165-8
- Aronne LJ, et al. Orforglipron for maintenance of body weight reduction (ATTAIN-MAINTAIN). Nature Medicine 2026;32(7):2679-2687. DOI 10.1038/s41591-026-04386-7
- Rosenstock J, et al. Orforglipron in early type 2 diabetes (ACHIEVE-1). N Engl J Med 2025;393(11):1065-1076. DOI 10.1056/NEJMoa2505669
- Welch M, et al. Orforglipron compared with dapagliflozin in type 2 diabetes (ACHIEVE-2). The Lancet 2026;408(10550):125-140. DOI 10.1016/S0140-6736(26)00800-7
- Rosenstock J, et al. Once-daily oral orforglipron compared with oral semaglutide in type 2 diabetes (ACHIEVE-3). The Lancet 2026;407(10534):1147-1160. DOI 10.1016/S0140-6736(26)00202-3
- Klein KR, et al. Cardiovascular safety of orforglipron versus insulin glargine (ACHIEVE-4). The Lancet 2026;408(10564):1557-1570. DOI 10.1016/S0140-6736(26)01865-9
- Wharton S, et al. Daily oral GLP-1 receptor agonist orforglipron for adults with obesity (phase 2). N Engl J Med 2023;389(10):877-888. DOI 10.1056/NEJMoa2302392
- Frias JP, et al. Oral orforglipron in type 2 diabetes: phase 2 dose-response study. The Lancet 2023;402(10400):472-483. DOI 10.1016/S0140-6736(23)01302-8
- Eli Lilly press release, 6 Nov 2025: eloralintide phase 2 results
- Billings LK, et al. Eloralintide phase 2, 48-week trial. The Lancet 2025;406:2631-2643. DOI 10.1016/S0140-6736(25)02155-5
- Briere DA, et al. Discovery and first-in-human study of eloralintide. Molecular Metabolism 2025;102:102271. DOI 10.1016/j.molmet.2025.102271
- ClinicalTrials.gov NCT07321886, ENLIGHTEN-1
- Eli Lilly Q3 2026 results, 29 Oct 2026
- Wilding JPH, et al. Semaglutide STEP 1. N Engl J Med 2021;384:989-1002. DOI 10.1056/NEJMoa2032183
- Jastreboff AM, et al. Tirzepatide SURMOUNT-1. N Engl J Med 2022;387:205-216. DOI 10.1056/NEJMoa2206038
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