What is Foundayo?

April 1, 2026 - Foundayo (orforglipron) tablets are now FDA-approved for use in adults with obesity, or who are overweight with weight-related medical problems.

Foundayo is an oral, once-daily weight loss tablet developed by Eli Lilly. As a small-molecule, nonpeptide GLP-1 receptor agonist, it can be taken at any time without food or water restrictions, which represents a significant advantage over existing injectable and oral GLP-1 therapies. It gained FDA approval on April 1, 2026 for chronic weight management and is available at a reduced cost compared to currently available injectable anti-obesity/type 2 GLP-1 drugs. It is not currently approved for Type 2 diabetes, but approval is expected to be sought and granted late 2026.

How is Foundayo administered?

Foundayo is taken orally as a once-daily pill with no dietary restrictions. It can be taken with or without food, and without timing requirements for water intake.

How does Foundayo work?

Foundayo is a nonpeptide glucagon-like peptide-1 (GLP-1) receptor agonist that works by mimicking a natural hormone called GLP-1 by activating the GLP-1 receptor. This hormone is produced in the gut after eating and its effects include:

• Helping with appetite control by signaling to your brain that you are full
• Stimulating insulin release from the pancreas and helping to maintain stable glucose levels
• Slowing down gastric emptying and helping you feel fuller for a longer period of time.

Foundayo differs from other GLP-1 medications because of its small molecule structure (unlike the large peptide molecules in typical GLP-1 medications, such as semaglutide). Because Foundayo is a small molecule, it is absorbed efficiently through the gut, and a high proportion reaches the bloodstream, where it can take effect.

The size of larger peptide-based drugs like semaglutide makes them vulnerable to being broken down in the digestive tract, meaning very little survives to be absorbed, which is why they are typically given by injection instead. Oral forms of semaglutide do exist (Rybelsus, Ozempic tablets, Wegovy pill), but they come with strict requirements: They must be taken on an empty stomach with a small sip of water, followed by a waiting period before eating, drinking, or taking other medicines.

Foundayo has none of these restrictions. It can be taken once daily at any time, with or without food.

What are the side effects of Foundayo?

The most common side effects of Foundayo are mild-to-moderate gastrointestinal events such as:

• Nausea
• Constipation
• Diarrhea
• Vomiting
• Dyspepsia (indigestion)
• Abdominal pain
• Headache
• Abdominal distension (bloating)
• Fatigue
• Burping or belching
• Gastroesophageal reflux disease
• Flatulence
• Hair loss.

In the Phase 3 ACHIEVE-3 head-to-head trial, discontinuation due to side effects was roughly twice as common with Foundayo than with semaglutide — 8.7% and 9.7% for the 12 mg and 36 mg doses respectively, compared to 4.5% and 4.9% for semaglutide 7 mg and 14 mg.

Related questions

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How effective is Foundayo?

Phase 3: ACHIEVE-3: Foundayo vs. Oral Semaglutide (February 2026)

Published in The Lancet on February 26, 2026, ACHIEVE-3 is the first Phase 3 head-to-head trial comparing orforglipron (Foundayo) directly with oral semaglutide in 1,698 adults with type 2 diabetes inadequately controlled with metformin. The 52-week trial tested orforglipron 12 mg and 36 mg against oral semaglutide 7 mg and 14 mg.

Overall, orforglipron 36 mg demonstrated superior weight reduction compared with oral semaglutide 14 mg, achieving a mean body weight reduction of approximately 8% (~9 kg) versus 5% (~5 kg), respectively.

Phase 3: ACHIEVE-4: Foundayo vs. Insulin glargine (April 2026)

ACHIEVE-4 (NCT05803421), the largest and longest Phase 3 study of Foundayo (orforglipron) to date, enrolled more than 2,700 participants across 15 countries and evaluated its efficacy and safety compared to insulin glargine in adults with type 2 diabetes and obesity or overweight at increased cardiovascular risk.

Foundayo met the primary endpoint, demonstrating non-inferior cardiovascular risk versus insulin glargine, with a 16% lower risk of MACE-4 events (HR: 0.84; 95% CI: 0.59–1.20) and a 23% lower risk of MACE-3 events. A pre-planned analysis further showed a 57% lower risk of all-cause mortality with Foundayo versus insulin glargine (HR: 0.43; 95% CI: 0.25–0.75; nominal p=0.002), suggesting broader health benefits beyond cardiovascular outcomes.

In addition, Foundayo demonstrated superior improvements in HbA1c and body weight at 52 weeks versus insulin glargine, which were sustained through 104 weeks of treatment. Clinically meaningful improvements were also observed across key cardiovascular risk factors, including non-HDL cholesterol, systolic blood pressure, triglycerides, and hsCRP, reaffirming its cardiometabolic profile across a high-risk population.

Health Guide

GLP-1 weight loss drugs explained

Discover how medications like Mounjaro, Wegovy and Zepbound can help with weight loss and diabetes management.

Explore the guide

• How it works
• Side effects
• Cost
• Weight loss

Regulatory Status

Lilly has submitted orforglipron to regulators in over 40 countries. In the United States, the FDA approved Foundayo for the obesity indication on April 1, 2026. Submission for type 2 diabetes in the U.S. is planned later in 2026.

About Orforglipron

Orforglipron was discovered by Chugai Pharmaceutical Co., Ltd. and licensed by Eli Lilly in 2018. Lilly is also studying it as a potential treatment for obstructive sleep apnea (OSA) and hypertension in adults with obesity. Lilly also manufactures Mounjaro, an injectable dual GIP/GLP-1 receptor agonist for type 2 diabetes in adults and children 10 years and older.

Read next

See also:

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Drug information

• Foundayo Information for Consumers
• Foundayo prescribing info & package insert (for Health Professionals)
• Side Effects of Foundayo (detailed)
• Foundayo user reviews (57)

Related support groups

• Foundayo (15 questions, 6 members)
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