FDA approves Eli Lilly’s oral GLP-1 Foundayo for weight loss

The US FDA approved Eli Lilly and Company’s oral GLP-1 receptor agonist orforglipron (Foundayo) on April 1, 2026 for chronic weight management in adults with obesity, or those who are overweight with at least one weight-related condition, alongside a reduced-calorie diet and increased physical activity. The approval marks Lilly’s second cleared obesity medicine and establishes orforglipron as the first non-peptide small-molecule GLP-1 receptor agonist to reach the US market for weight management, following Novo Nordisk’s peptide-based oral semaglutide, which was approved in 2025.

Orforglipron is available as a once-daily oral tablet across multiple dose strengths ranging from 0.8 mg to 17.2 mg. The drug can be taken at any time of day without food or water restrictions, a formulation advantage over oral semaglutide, which requires specific fasting and fluid conditions. Lilly said it will make the drug available through its LillyDirect platform beginning April 6, with subsequent rollout through US retail pharmacies and telehealth providers. The company said eligible patients with commercial insurance could access the drug for as little as USD 25 per month, with a self-pay price starting at USD 149 per month for the lowest dose.

Pivotal data readouts

The approval was supported by the ATTAIN Phase III clinical development program, which enrolled more than 4,500 participants across two global registration trials. ATTAIN-1 (NCT05869903) was a 72-week, randomized, double-blind, placebo-controlled trial in 3,127 adults with obesity or overweight with at least one comorbidity — hypertension, dyslipidemia, obstructive sleep apnea, or cardiovascular disease — who did not have diabetes.

The primary objective was superiority over placebo in body weight reduction from baseline at 72 weeks. Participants receiving the highest dose lost an average of 27.3 pounds (12.4%) at 72 weeks, compared with 2.2 pounds (0.9%) with placebo. Across all randomized participants, mean weight loss was 25 pounds (11.1%) versus 5.3 pounds (2.1%).

The ATTAIN program also enrolled a second trial, ATTAIN-2 (NCT05872620), which evaluated orforglipron in more than 1,600 adults with obesity or overweight and type 2 diabetes over the same 72-week period. Lilly said treatment was also associated with reductions in waist circumference, non-HDL cholesterol, triglycerides, and systolic blood pressure across doses. The safety profile was consistent with the GLP-1 receptor agonist class, with the most common adverse events including nausea, constipation, diarrhea, vomiting, and related gastrointestinal effects. The prescribing information includes a warning regarding thyroid tumors and contraindications in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2.

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Development context

Orforglipron was originally discovered by Chugai Pharmaceutical Co., Ltd. and licensed to Lilly in 2018 for USD 50 million upfront, with Chugai retaining eligibility for milestone payments and royalties. Lilly assumed full worldwide development and commercialization responsibility, advancing the molecule through the ATTAIN program and filing the NDA that produced this approval. Beyond chronic weight management, orforglipron is under active investigation for type 2 diabetes, obstructive sleep apnea, osteoarthritis knee pain, hypertension, peripheral artery disease, and stress urinary incontinence, the company said.

The approval enters a rapidly evolving obesity treatment landscape. Lilly’s tirzepatide (Zepbound), a dual GIP/GLP-1 receptor agonist administered as a weekly injection, was approved by the US FDA for obesity in November 2023. Novo Nordisk’s oral semaglutide 25 mg, a peptide-based formulation requiring fasting administration, was approved in December 2025 as the first oral GLP-1 in the indication. Orforglipron introduces a distinct small-molecule, non-peptide option within the oral segment, potentially addressing adherence and access barriers associated with injectable therapies and fasting requirements.

Several other candidates remain in development, including Pfizer’s danuglipron, AstraZeneca’s AZD9550, Novo Nordisk’s cagrilintide/semaglutide combination, and Lilly’s own triple agonist retatrutide. Amgen’s maridebart cafraglutide, a bispecific GLP-1 agonist and GIP receptor antagonist, represents a mechanistically distinct approach within the same pathway.

Fewer than 1 in 10 people eligible for GLP-1 therapy are currently receiving treatment, according to company estimates, reflecting barriers related to access, stigma, and regimen complexity. The approval adds an oral, unrestricted-dosing option to a class where injectable administration and fasting requirements have limited uptake for some patients. Whether this formulation advantage translates into improved adherence or broader population-level adoption remains to be seen in real-world data. Lilly said it has submitted orforglipron for regulatory review in more than 40 countries across weight management and type 2 diabetes indications.