Summary

Orforglipron is an oral, small-molecule GLP-1 receptor agonist developed by Eli Lilly for type 2 diabetes and obesity. In 2025, it became the first oral GLP-1 agonist to receive FDA approval for obesity, marketed under the brand name Foundayo. It is not yet licensed in the UK. The ACHIEVE Phase 3 programme demonstrated weight loss of 12–15%, comparable to injectable GLP-1 agonists, with the convenience of once-daily oral dosing without food restrictions.

Mechanism

Orforglipron is a small-molecule agonist of the glucagon-like peptide-1 (GLP-1) receptor. By activating GLP-1 receptors in the pancreas, brain, and gastrointestinal tract, it increases glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and reduces appetite. Unlike peptide-based GLP-1 agonists, orforglipron's small-molecule structure allows oral absorption without degradation in the gastrointestinal tract, eliminating the need for injection or co-formulation with absorption enhancers.

Evidence base

Strong evidence. The ACHIEVE Phase 3 programme, including ACHIEVE-1 published in the New England Journal of Medicine (2025), demonstrated 12–15% mean weight loss in adults with obesity. Orforglipron received FDA approval for obesity in 2025 under the brand name Foundayo — the first oral GLP-1 agonist approved for this indication. ACHIEVE-3 demonstrated superior glycaemic control in type 2 diabetes. UK licensing is pending.

Protocols

Orforglipron is administered as a once-daily oral tablet. Dose escalation from a low starting dose is recommended to minimise gastrointestinal adverse events. Unlike oral semaglutide (Rybelsus), orforglipron does not require fasting or specific timing relative to meals. Specific dosing should be referenced from the FDA prescribing information and published trial protocols. Not licensed in the UK.

Orforglipron is not licensed by the MHRA for use in the UK. It has received FDA approval in the United States (brand name: Foundayo). Eli Lilly is expected to seek MHRA marketing authorisation. Upon UK approval, it would be classified as a Prescription-Only Medicine (POM). It is not a controlled substance. For research purposes, orforglipron may be obtained for in vitro or preclinical research under standard research chemical regulations.

Vendor notes

Orforglipron is not commercially available in the UK as it is not MHRA-licensed. UK researchers seeking orforglipron for legitimate in vitro or preclinical research should source from established research chemical suppliers with appropriate purity documentation (COAs). It should not be purchased for human consumption.

References

  1. Jastreboff AM, et al. 'Orforglipron for Obesity in Adults without Diabetes — The ACHIEVE-1 Trial.' New England Journal of Medicine, 2025.
  2. Drugs.com. 'Foundayo (orforglipron) FDA Approval History.' Accessed 2025.
  3. FDA. 'FDA Approves First New Molecular Entity under National Priority Voucher Pilot Program.' FDA press release, 2025.
  4. Eli Lilly and Company. Investor news releases on orforglipron ACHIEVE programme, 2025–2026.