Orforglipron
Orforglipron (Foundayo / LY3502970)
First oral non-peptide small-molecule GLP-1 receptor agonist. FDA approved as Foundayo (April 1, 2026) for chronic weight management in adults: uniquely, with NO food, water, or fasting restrictions (unlike Rybelsus). Phase 3 ATTAIN-1 (NEJM 2025): -11.2% weight loss at 36mg over 72 weeks. Beat oral semaglutide head-to-head in T2D (ACHIEVE-3 Feb 2026). Solves the operational nightmare of Rybelsus's 30-min fasting window.
At a glance
- Half-life
- ~48 h Single-dose mean t½ 24.6-35.3h; multiple-dose (steady-state) t½ 48.1-67.5h. Supports once-daily oral dosing. Tmax 4-8h post oral dose. Bioavailability ~30-40%. Food has minimal impact on AUC and Cmax (up to 24% lower with food, but tmax and t½ unchanged).
- Routes
- Oral
- Evidence base
- 3 studies 3 human
Mechanism
Non-peptide small molecule that binds and activates the GLP-1 receptor through an allosteric site distinct from the orthosteric site bound by peptide GLP-1 RAs. Despite different binding mode, downstream signaling cascade (cAMP, beta-arrestin recruitment, insulin secretion) is similar to peptide GLP-1 RAs. Phase 1a established t½ 24.6-67.5h and dose-proportional PK. Key advantages of small-molecule design: oral bioavailability without absorption enhancers (no SNAC needed), no food/water restrictions, cheaper to manufacture, stable in standard tablet formulation. Pharmacological effects same as peptide GLP-1 RAs: glucose-dependent insulin secretion, glucagon suppression, gastric emptying delay, central appetite suppression. Phase 2: -8.6% to -12.6% body weight across doses. ATTAIN-1 phase 3 (n=3,127): 36mg -11.2% vs -2.1% placebo at 72 weeks.
Dosing
Any amounts shown here are reported from published studies only. 3 of 3 catalogued studies involved human subjects. COMPOUND does not publish its own dosing guidance.
Where a study reports an amount, it appears in that study's entry below, attributed to the source.
Published evidence
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Human RCT 2025
Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment (ATTAIN-1)
Phase 3 obesity, n=3,127, 72 weeks: 6mg -7.5%, 12mg -8.4%, 36mg -11.2% vs placebo -2.1%. 54.6% of 36mg arm had ≥10% loss; 36% had ≥15%; 18.4% had ≥20%.
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Human RCT 2023
Orforglipron (LY3502970), a novel, oral non-peptide glucagon-like peptide-1 receptor agonist: A Phase 1a single- and multiple-ascending-dose study
Phase 1a healthy: t½ 24.6-67.5h depending on dose/timing. Dose-proportional PK. Well tolerated.
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Human RCT 2023
Daily Oral GLP-1 Receptor Agonist Orforglipron for Adults with Obesity
Phase 2 obesity, 36 weeks: -8.6% to -12.6% across 12-45mg doses vs placebo -2.0%. Foundation for phase 3.
Reported side effects
- Nausea
- Very common Moderate · Phase 3 ATTAIN-1: nausea common, comparable to injectable GLP-1s. Dose-dependent, escalation-related.
- Vomiting
- Common Moderate · Class GI profile.
- Diarrhea
- Common Mild · Class effect.
- Constipation
- Common Mild · Class effect.
- Decreased appetite
- Very common Mild · Wanted effect.
- Headache
- Occasional Mild · Class effect.
- Hepatic enzyme elevation
- Occasional Moderate · Small-molecule organ-specific concern. Phase 3 monitoring showed no major hepatotoxicity signal but FDA label may include hepatic monitoring.
- Hypoglycemia
- Rare Moderate · Glucose-dependent mechanism; rare unless combined with SU/insulin.
- Thyroid C-cell tumors
- Rare Serious · BOXED WARNING expected (class effect from rodent carcinogenicity studies on GLP-1 RAs). Contraindicated with personal/family hx of MTC or MEN-2.
Interactions
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Insulin or sulfonylurea Synergy
GLP-1 mechanism + insulin/SU. Hypoglycemia risk.
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Oral medications (general) Absorption interference
GLP-1 receptor activation slows gastric emptying, but to a lesser degree than injectable peptide GLP-1 RAs (oral small molecule has lower peak exposures despite similar AUC). May modestly affect oral drug absorption.
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Semaglutide (SC) Redundant
Overlapping GLP-1 agonism. Concurrent GLP-1 RA not recommended.
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Semaglutide (Oral) Redundant
Both are oral GLP-1 RAs: additive effects, no benefit.
Storage
Standard tablet: room temperature storage. Specifics in PI.