What is Foundayo™ (orforglipron)?

What the US approval covers

The label approves Foundayo™ for lowering excess weight and keeping it off over the long term, always together with eating fewer calories and being more active. It applies to adults with obesity, and to adults with overweight who have at least one weight-related condition ^[1]. The Medication Guide says the same in plainer words: it helps adults with obesity, or some adults with overweight and weight-related medical problems, lose excess weight and keep it off ^[2].

Two limits come with the approval. Using Foundayo™ together with another GLP-1 receptor agonist is not recommended, and it is not approved for children, because safety and effectiveness have not been established in paediatric patients ^[1]. The FDA’s Drugs@FDA database lists the original approval of application NDA 220934 on 1 April 2026, after a standard review ^[3].

Where else it is authorised

Outside the US the wording differs, most visibly for type 2 diabetes. The table shows what each regulator had published when we checked on 20 October 2026.

How it works

Orforglipron binds to and activates the human GLP-1 receptor, the target of the gut hormone GLP-1. The label describes GLP-1 as a physiological regulator of appetite and calorie intake, and notes that animal studies showed orforglipron reaching and activating nerve cells in brain regions that regulate appetite ^[1].

In people, the label says Foundayo™ decreases food intake, likely by decreasing appetite, and reduces body weight with greater loss of fat mass than lean mass. It also delays stomach emptying; the delay is largest after the first dose and diminishes over time ^[1]. When blood sugar is high it stimulates insulin release, which is why the label pays attention to people who also take insulin or a sulfonylurea ^[1].

A different kind of molecule

Semaglutide and tirzepatide are modified peptides, chains of amino acids built to resemble natural gut hormones. The Foundayo™ label describes orforglipron as a small chemical molecule; as the calcium salt it weighs about 902 g/mol, a fraction of the size of the peptide medicines ^[1]. That difference explains three things you will meet in the rest of the label: there is no empty-stomach rule, a liver enzyme rather than protein breakdown clears it, and it leaves the body within days rather than weeks.

How the label says it is taken

• One tablet by mouth once a day, with or without food, swallowed whole without breaking, crushing or chewing. No more than one tablet a day ^[1][2].
• The label starts at 0.8 mg daily and raises the dose in steps at least 30 days apart, to 2.5 mg and then 5.5 mg, which it says reduces the risk of stomach side effects. Further steps to 9 mg, 14.5 mg or 17.2 mg depend on response and tolerability; 17.2 mg is the maximum ^[1].
• A missed dose is taken as soon as possible, never two in one day. If 7 or more doses in a row are missed, the label restarts the steps at a lower dose, and the Medication Guide asks you to call your healthcare provider about how to restart ^[1][2].
• If too much is taken, the Medication Guide points to your healthcare provider, the Poison Help line or the nearest emergency room ^[2].
• Tablets come in bottles with a desiccant and are kept at room temperature, 20°C to 25°C, with short excursions between 15°C and 30°C allowed ^[1].

What the trials measured

The label describes two 72-week trials in which everyone also received diet and activity counselling. Trial 1 enrolled 3,127 adults with obesity, or overweight with a related condition, without type 2 diabetes. Average weight fell by 7.4%, 8.3% and 11.1% with 5.5 mg, 9 mg and 17.2 mg, compared with 2.1% on placebo ^[1].

Trial 2 enrolled 1,613 adults with type 2 diabetes. Average weight fell by 5.1%, 7% and 9.6% with the three doses, compared with 2.5% on placebo. These are group averages; between 19% and 30% of participants in each group stopped the trial drug early ^[1].

The published reports of these trials, named ATTAIN-1 and ATTAIN-2, give the doses as 6, 12 and 36 mg of an investigational formulation; the label presents the same groups as the equivalent Foundayo™ tablet doses ^[1][7][8]. Other phase 3 trials studied type 2 diabetes, among them ACHIEVE-1 against placebo and ACHIEVE-3, an open-label comparison with oral semaglutide ^[9][10]. The US label does not describe them. Our article on Foundayo™’s clinical studies goes through the whole programme.

Side effects in the trials

Side effects reported in at least 5% of people, and more often than on placebo, were nausea, constipation, diarrhoea, vomiting, indigestion, abdominal pain, headache, a swollen belly, tiredness, belching, reflux, gas and hair loss ^[1]. Nausea rose with the dose, from 26% at 5.5 mg to 35% at 17.2 mg, against 10% on placebo ^[1].

Digestive side effects of any kind affected 60% to 69% of people on Foundayo™ and 37% on placebo. Of those who had them, 60% called them mild, 36% moderate and 4% severe, and nausea, vomiting and diarrhoea were most frequent while the dose was being raised ^[1]. Overall, 8% stopped because of side effects (6%, 9% and 10% by dose), compared with 3% on placebo ^[1].

A few findings outside the digestive system are worth knowing. Pulse rose on average by 4 to 5 beats per minute, against 0.5 on placebo. Low blood pressure was reported in 2% against 0.5%, and in 4% of people who also took blood-pressure medicines. Hair loss was linked with weight reduction and was reported by 7% of women and 0.9% of men on the medicine ^[1].

Warnings and who should not take it

• Thyroid: the boxed warning rules Foundayo™ out for anyone who has had medullary thyroid carcinoma, or whose relative has, and for anyone with MEN 2. A known serious allergy to orforglipron or the tablet ingredients is the other contraindication ^[1].
• Pancreatitis: six adjudicated cases in people on Foundayo™, against one person on placebo; the label says to stop the medicine if pancreatitis is suspected ^[1].
• Severe digestive reactions in about 3% against 1% on placebo; not recommended for people with severe gastroparesis ^[1].
• Kidney injury from fluid loss, mostly after vomiting, diarrhoea or nausea, especially while starting and raising the dose ^[1].
• Low blood sugar: in the trial of people with type 2 diabetes, 2% against 0.2% on placebo, and 7% of those also taking a sulfonylurea ^[1].
• Also listed: worsening of existing diabetic eye disease, gallbladder disease (gallstones in 1% against 0.7%) and inhaling stomach contents during anaesthesia or deep sedation, which is why the label asks you to tell providers before any planned procedure ^[1][2].

Interactions, pregnancy, liver and kidneys

• Strong CYP3A4 inhibitors raise orforglipron levels, so the label caps the dose at 9 mg with them and says to avoid those that also block OATP1B, such as ritonavir. Strong CYP3A4 inducers are to be avoided, and with moderate ones the effect is monitored ^[1].
• Simvastatin is limited to 20 mg a day, because orforglipron doubled the level of its active form. With insulin or a sulfonylurea, the prescriber may lower that dose when Foundayo™ starts ^[1].
• Slower stomach emptying may affect tablets taken by mouth. For the birth control pill, the label asks for a non-oral method, or a barrier method added to the pill, during the first 30 days and the 30 days after each dose step ^[1].
• Pregnancy: it may cause fetal harm and is stopped when a pregnancy is recognised; a pregnancy registry is planned. It is not recommended while breastfeeding ^[1][2].
• Liver and kidneys: not recommended in severe liver impairment; no dose change for mild or moderate liver impairment or for kidney impairment ^[1].
• Older adults: 13% of trial participants on Foundayo™ were 65 or older, and no overall differences in safety or effectiveness were seen ^[1].

Foundayo™ is a trademark of Eli Lilly and Company. PepLabo is not affiliated with or endorsed by Eli Lilly and Company.

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