Made in USA · ≥99% HPLC
Metabolic Peptide
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GLP 3 (Reta)
LY3437943Triple agonistGIP / GLP-1 / glucagon
A synthetic triple GIP, GLP-1, and glucagon receptor agonist (39-amino-acid incretin analog), supplied as sterile lyophilized powder for in-vitro metabolic research.
Price range: $89.95 through $449.95
In stock
For laboratory and research use only. Not for human consumption.
This product is not a drug, food or cosmetic. It is sold exclusively to qualified researchers and licensed laboratories.
Tested by Freedom Diagnostics TestingHPLC purity + LC-MS identityLot-matched COA on-site
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Verified COA
Batch-tested & posted · Freedom Diagnostics
Purity (HPLC-UV)99.76%
Identity (LC-MS)Confirmed
Net content21.01 mg
ReportedJun 20, 2026
US-synthesizedMade & lab-released in the United States
Independent COAThird-party Certificate of Analysis per lot
HPLC + LC-MSPurity by HPLC, identity by mass spectrometry
Same-day dispatchOrders before 2 PM CT ship the same business day
What is GLP-3 (Reta)?
GLP-3 (Reta) (development code LY3437943) is a synthetic single-molecule "triple agonist" that activates three metabolic hormone receptors at once — the GIP receptor, the GLP-1 receptor, and the glucagon receptor. Engaging all three pathways simultaneously drives glucose-dependent insulin secretion through the two incretin arms while adding glucagon-receptor agonism, the pharmacological feature that distinguishes it from single (GLP-1 (Sema)) and dual (GLP-2 (Triz)) incretin agonists.
Research areas where laboratories buy GLP-3 (Reta) for in vitro work include triple-receptor binding and cAMP-signaling assays in cells co-expressing GIP, GLP-1 and glucagon receptors, glucose-dependent insulin-secretion studies in pancreatic beta-cell models, metabolic-flux research in rodent models, and comparative dual- versus triple-agonist pharmacology. It is an investigational compound and is not approved by the FDA for any indication.
Every lot, independently verified
Independently third-party tested and matched to the lot ID printed on your vial. Values below are from the latest released lot.
99.76%
HPLC-UV Purity
Passed full QC panel
Independent third-party lab (Freedom Diagnostics Testing)
View COA (PDF)
Latest batch · tested 20 Jun 2026 · Freedom Diagnostics (USA)
Lot details
ProductGLP-3 (Reta) 20 mg
LotClear Cap/Bronze Crimp
AppearanceWhite lyophilized powder
Accession #2606170094
Reported20 Jun 2026
Full QC panel · third-party lab7 assays
Purity (HPLC-UV)99.76% ✓
Identity (LC-MS)GLP-3 (Reta) ✓
HPLC conformity (2×)Confirmed ✓
Net content21.01 mg ✓
Heavy metals (ICP-MS)Not Detected ✓
SterilityNo Growth ✓
Endotoxin (USP <85>)Within limits ✓
Every lot is released against Koi's full QC panel — HPLC purity, LC-MS identity, net content, heavy metals, sterility, and endotoxin — by an independent third-party laboratory (Freedom Diagnostics Testing). Values shown are from the latest released lot and vary batch to batch; per-test results are recorded in each lot's release documentation and matched to the lot ID printed on the vial.
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Compound information
Chemical & structural reference data — specifications, molecular profile and handling.
Product Specifications
CompoundGLP-3 (Reta) (synthetic triple GIP/GLP-1/glucagon receptor agonist, lipidated)
Vial size10 mg & 30 mg
Purity≥99% by HPLC
Identity confirmationMass spectrometry
FormLyophilized white to off-white powder
Appearance in solutionClear, colorless solution
ManufacturingSynthesized and lyophilized in the United States
Quality testingIndependent third-party laboratory release (Freedom Diagnostics Testing)
Molecular Profile
ClassTriple GIP / GLP-1 / glucagon receptor agonist
Backbone39-amino-acid incretin analog, fatty-acid acylated
Molecular weight≈ 4731 g/mol
CAS number2381089-83-2
Other namesLY3437943
Structure class39-amino-acid lipidated triple-receptor incretin peptide; fatty-diacid side chain enabling albumin binding and extended half-life
Storage & Handling
AppearanceWhite lyophilized powder
SolubilitySterile water or buffer · neutral pH
Storage · powder−20 °C, desiccated, dark (−80 °C long-term)
In solution2–8 °C; aliquot & freeze, avoid freeze-thaw
GLP-3 (Reta) Mechanism of Action
- Acts as an agonist at three receptors — the GIP receptor, the GLP-1 receptor, and the glucagon receptor — the defining "triple agonist" pharmacology that separates it from single- and dual-incretin compounds.
- Engages Gαs / adenylyl-cyclase / cAMP signaling at each of the three receptors in receptor-expressing cell models.
- Potentiates glucose-dependent insulin secretion through the GIP and GLP-1 incretin arms in pancreatic beta-cell assays.
- Adds glucagon-receptor agonism on top of the dual-incretin mechanism, a contribution studied in lipid-metabolism pathways in preclinical models.
- Carries a fatty-acid acylation that enables reversible serum-albumin binding and a markedly extended half-life relative to native incretin peptides.
- Serves as the reference triple-receptor tool compound for dissecting the relative contribution of GIP, GLP-1 and glucagon signaling in multi-incretin pharmacology.
GLP-3 (Reta) Research Applications
- GIP, GLP-1 and glucagon receptor binding and cAMP-accumulation assays in cells co-expressing the three receptors, where GLP-3 (Reta) is the standard reference triple agonist.
- Glucose-dependent insulin-secretion studies in pancreatic beta-cell models, isolating the incretin contribution to insulinotropic activity.
- Metabolic-flux research in rodent models, probing the glucagon-receptor arm absent from single- and dual-agonist compounds.
- Comparative dual- versus triple-agonist pharmacology, run alongside GLP-1 (Sema) (single) and GLP-2 (Triz) (dual) to dissect receptor-specific effects.
- Albumin-binding and half-life characterization of fatty-acylated incretin analogs.
- Structure-activity studies of triple-receptor incretin peptides and engineered receptor selectivity.
Why Buy GLP-3 (Reta) from Koi Peptides?
- Every batch of Koi GLP-3 (Reta) is synthesized and lyophilized in the United States, then released against independent third-party laboratory (Freedom Diagnostics Testing) testing.
- Each lot is tested by HPLC for purity, LC-MS for identity confirmation, and screened for endotoxin before release.
- The lot ID is printed on every vial and ties back to a public COA library, so researchers can verify documentation before they buy and after the vial arrives.
- Orders placed before 2 PM CT ship the same business day, and shipping is free on orders over $200.
References
The laboratory and preclinical research behind GLP-3 (Reta) — cited for scientific context.
Cell Metabolism
LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist
Molecular Metabolism
Selection and progression of unimolecular agonists at the GIP, GLP-1, and glucagon receptors
Molecular Metabolism
Glucagon-like peptide 1 (GLP-1)
View all references +
- Coskun, T., et al. (2022). LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist. Cell Metabolism, 34(9), 1234–1247. doi.org/10.1016/j.cmet.2022.07.013
- Knerr, P. J., et al. (2022). Selection and progression of unimolecular agonists at the GIP, GLP-1, and glucagon receptors. Molecular Metabolism, 63, 101533. doi.org/10.1016/j.molmet.2022.101533
- Müller, T. D., et al. (2019). Glucagon-like peptide 1 (GLP-1). Molecular Metabolism, 30, 72–130. doi.org/10.1016/j.molmet.2019.09.010
Regulatory Status
Regulatory status — provided for research context.
Regulatory Status
Regulatory status — provided for research context.
FDA Status
GLP-3 (Reta) (LY3437943) is an investigational compound and is not approved by the FDA for any indication. The research-grade material supplied by Koi Peptides is synthesized for laboratory research only; it is not formulated, packaged or labeled as a drug, food or cosmetic.
Disclaimer
For laboratory and research use only. Not for human consumption. This product is not a drug, food or cosmetic. It is sold exclusively to qualified researchers and licensed laboratories. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
Frequently Asked Questions About GLP-3 (Reta)
What is GLP-3 (Reta) used for in research?+
GLP-3 (Reta) is the reference triple GIP/GLP-1/glucagon receptor agonist in metabolic pharmacology research. In vitro studies use it to characterize binding and cAMP signaling across the three receptors, glucose-dependent insulin secretion in beta-cell models, and metabolic pathways in rodent models. Comparative work pairs it against GLP-1 (Sema) (single agonist) and GLP-2 (Triz) (dual agonist) to isolate the glucagon-receptor contribution.
What purity is Koi's GLP-3 (Reta)?+
Koi GLP-3 (Reta) is ≥99% pure by HPLC (latest released lot 99.76%), with identity confirmed by LC-MS. Every lot is released against independent third-party laboratory (Freedom Diagnostics Testing) testing covering HPLC purity, LC-MS identity, net content, heavy metals, sterility, and endotoxin, and the COA is published against the lot number printed on the vial.
How do I prepare a GLP-3 (Reta) solution?+
Dissolve in sterile water or a suitable buffer at neutral pH. Add diluent slowly down the vial wall rather than onto the cake, and avoid vortexing. Prepare working dilutions immediately before use, and for sterile cell-culture work filter through a 0.22 µm low-protein-binding filter. Store prepared solutions at 2 to 8 °C, or aliquot and freeze at −20 °C or below.
What is the CAS number for GLP-3 (Reta)?+
The CAS number for GLP-3 (Reta) is 2381089-83-2. It is also cataloged under the Eli Lilly development code LY3437943. It is a fatty-acylated 39-amino-acid triple GIP/GLP-1/glucagon receptor agonist with a molecular weight of approximately 4731 g/mol.
How does GLP-3 (Reta) compare with GLP-1 (Sema) and GLP-2 (Triz) as a research tool?+
GLP-1 (Sema) is a single GLP-1 receptor agonist, GLP-2 (Triz) is a dual GLP-1R/GIPR agonist, and GLP-3 (Reta) adds glucagon-receptor activity on top to become a triple GLP-1R/GIPR/GCGR agonist. Researchers studying receptor-specific contributions often run all three compounds in parallel to isolate the activity of each individual receptor in incretin and metabolic signaling networks.
Is GLP-3 (Reta) FDA-approved?+
No. GLP-3 (Reta) is an investigational compound and is not approved by the FDA for any indication. The material supplied by Koi Peptides is for laboratory and research use only.
How should GLP-3 (Reta) be stored?+
Store the lyophilized powder at −20 °C, desiccated and protected from light; for long-term storage −80 °C is preferred. Minimize handling time outside the freezer. Once dissolved, store at 2 to 8 °C or aliquot and freeze. Avoid repeated freeze-thaw cycles, which can promote aggregation in lipidated peptides.
Is GLP-3 (Reta) for human use?+
No. GLP-3 (Reta) is for laboratory and research use only and is not for human consumption. It is sold exclusively to qualified researchers and licensed laboratories.
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