Orforglipron (revision 17)
Old revision·23:11, 30 Aug 2025·MolarMassMaeve
| OrforglipronInvestigational | |
|---|---|
| Development code | LY3502970 |
| Class | Small-molecule GLP-1 receptor agonist |
| Route | Oral, once daily |
| Status | Phase 3; not approved |
| Contrast with oral peptide | |
| Bioavailability | Not limited by proteolysis |
| Food restriction | None required |
| Compare | Oral semaglutide, ≈0.4–1% with fasting conditions |
| Compound infobox · conventions | |
Orforglipron (development code LY3502970) is an investigational orally administered non-peptide agonist of the GLP-1 receptor. It is not a peptide and is not subject to proteolysis, so it requires neither an absorption enhancer nor the strict fasting conditions that govern oral semaglutide.[1]
Small-molecule agonism at a class B G-protein-coupled receptor was long considered difficult, because the natural ligand engages a large surface across two receptor domains.[2] Orforglipron binds a pocket near the extracellular face of the transmembrane bundle and stabilises an active conformation without reproducing the peptide's binding mode.[1]
Reported phase 2 results include glycated-haemoglobin reductions of up to about 2.1 percentage points in type 2 diabetes and weight reduction of up to about 14.7% at 36 weeks in obesity without diabetes. It is not approved in any jurisdiction.[3]
Molecular basis
[edit]The receptor's orthosteric peptide site is a poor target for a small molecule: the natural ligand contacts both the extracellular domain and the transmembrane bundle across a large interface, and a molecule of a few hundred daltons cannot reproduce that. Orforglipron instead occupies a pocket accessible from the extracellular face of the bundle and acts as an agonist by stabilising the same active receptor conformation by a different route.[1]
A consequence is species selectivity. The pocket differs between human and rodent receptors sufficiently that activity does not translate, and preclinical work required humanised receptor models — a practical complication of small-molecule work at this target that peptide agonists do not face.
Signalling profile differs from that of the peptide agonists, with a reported preference for cAMP accumulation over β-arrestin recruitment. Whether that difference has clinical consequences is unknown; see Receptor bias.[1]
Reported clinical findings
[edit]| Trial setting | Duration | Reported result |
|---|---|---|
| Type 2 diabetes, phase 2 | 26 weeks | HbA1c −2.1 percentage points at highest dose |
| Obesity without diabetes, phase 2 | 36 weeks | −14.7% weight at highest dose vs −2.3% placebo |
Gastrointestinal adverse events were dose-related and qualitatively similar to those of injected agonists, which argues that they are a receptor-level rather than a route-level phenomenon.[3][4]
Because the compound is not a peptide, it is subject to cytochrome-mediated metabolism and to the drug-interaction considerations that entails — a difference from the peptide agonists, which have essentially no cytochrome-mediated interactions. Interaction data are part of the phase 3 programme.
Significance for the field
[edit]An orally active agonist without food restrictions changes the practical economics of the class in three ways. Manufacture is by conventional small-molecule chemistry rather than by solid-phase peptide synthesis, which is cheaper at scale and is not constrained by peptide manufacturing capacity. Distribution requires no cold chain. And the administration burden falls to that of an ordinary tablet.[3]
Whether efficacy matches that of the injected peptides at their higher doses is the open question. The phase 2 figures are broadly comparable with semaglutide 2.4 mg and below those reported for tirzepatide 15 mg, but cross-trial comparison of this kind is unreliable and the phase 3 programme is the proper test.
See also
References
- ^ a b c d Kawai T, Sun B, Yoshino H, et al. "Structural basis for GLP-1 receptor activation by LY3502970, an orally active nonpeptide agonist." Proceedings of the National Academy of Sciences 117(47):29959–29967 (2020). DOI:10.1073/pnas.2014879117. PMID 33177239.
- ^ de Graaf C, Donnelly D, Wootten D, et al. "Glucagon-like peptide-1 and its class B G protein-coupled receptors." Pharmacological Reviews 68(4):954–1013 (2016). PMID 27630114.
- ^ a b c Frías JP, Hsia S, Eyde S, et al. "Efficacy and safety of oral orforglipron in patients with type 2 diabetes: a phase 2 randomised trial." The Lancet 402(10400):472–483 (2023). PMID 37369232.
- ^ Drucker DJ. "Mechanisms of action and therapeutic application of glucagon-like peptide-1." Cell Metabolism 27(4):740–756 (2018). PMID 29617641.