Retatrutide (Reta / GLP-3 RT) — Research Peptide
Retatrutide at a glance
Retatrutide (LY3437943; CAS 2381089-83-2) is an investigational peptide. It is informally called "Reta" or "GLP-3 RT"; there is no hormone named GLP-3. Peptide.Express supplies it as lyophilized powder in 10, 20 and 30 mg vials with a ≥99% HPLC sourcing specification, and publishes each lot's third-party Certificate of Analysis. For laboratory research use only. Not for human or veterinary use.
10mg presentation shown.
Packaging reference.
For laboratory research use only. Not for human or veterinary use.
US fulfillmentSame-day dispatch before 2 PM Eastern.
Free US shipping over $150Shipping options and processing times
Batch documentationView the selected batch reportPurity standard: Retatrutide is sourced to ≥99% HPLC — sourcing spec. How to read a peptide COA.
Batch documentation
Certificate of Analysis
Your batch. Independently tested.
Measured results, batch identifiers, and the original laboratory report for your selected presentation.
The batch behind your vial.
Packaging illustration- LOT / BATCH
- PX-L916
- COA ACCESSION
- 2609220039
Result for the selected batch.
- Selected presentation
- 10mg
- Laboratory
- Freedom Diagnostics
Batch details
- Sourcing specification
- ≥99% by HPLC
- Accession / CoA
- 2609220039
- Test Date
- September 22, 2026
- Laboratory
- Freedom Diagnostics
- Lot
- PX-L916
- Purity (measured)
- 99.94%
- Net content
- 11.36 mg
- Identity on CoA
- Retatrutide 10mg
- Reported
- 2026-09-24
Issued by an independent third-party laboratory; Peptide.Express does not test in-house. Results are reproduced as-is and confirm compound identity, purity, and the analytical methods used.
How to match your vial to this report
- 1.Match the presentationRetatrutide · 10mg selected.
- 2.Match the batchMatch lot PX-L916 to your vial.
- 3.Open the original CoAAccession 2609220039. Review the original methods and results.
Certificates by vial size
| Size | Lot | HPLC (measured) | Laboratory | Report date | File |
|---|---|---|---|---|---|
| 5 mg | R581826 | 99.77% | Mistral Diagnostics | 2026-08-29 | COA · Verify |
| 10 mg | PX-L916 | 99.94% | Freedom Diagnostics | 2026-09-24 | COA · Verify |
| 15 mg | PXC81626 | 99.74% | Mistral Diagnostics | 2026-08-14 | COA · Verify |
| 20 mg | PX-L916 | 99.97% | Freedom Diagnostics | 2026-09-24 | COA · Verify |
| 30 mg | PX-L916 | 99.98% | Freedom Diagnostics | 2026-09-24 | COA · Verify |
Names for this peptide
| Name | Meaning | Refers to |
|---|---|---|
| LY3437943 | development code used in published literature | retatrutide |
| GLP-3 | informal nickname (no hormone named GLP-3 exists) | retatrutide |
| GLP-3 RT | shorthand | retatrutide |
| RT3 / GLP3-R, GLP-R3 | shorthand variants | retatrutide |
| Reta | shorthand | retatrutide |
Continue exploring
Research Compounds Related to Retatrutide
Explore related compounds
Compound specifications
- Compound
- Retatrutide
- CAS
- 2381089-83-2
- Molecular formula
- C221H342N46O68
- Molecular weight
- 4,731 Da
- Purity
- ≥99% HPLC specification
- Form
- Lyophilized powder
- Storage (lyophilized)
- -20°C, desiccated, protected from light
- Storage (reconstituted)
- 2–8°C, use within 14–28 days
- Sequence
View published sequence
YAQGTFTSDYSILLDKKAQAAFIEYLLEGGPSSGAPPPS (39 residues; Aib 2 and 20, alpha-Me-Leu 13, C20 diacid on Lys17, C-terminal amide)
Reconstituting Retatrutide: step-by-step peptide reconstitution guide. Concentration maths: peptide reconstitution calculator.
Research reference
Retatrutide research reference
One compound. Three research targets.
Research examines activity at GIP, GLP-1, and glucagon receptors. Explore the compound's mechanism and comparative research below.
Triple GIPR / GLP-1R / GCGR agonist research overviewReceptor pharmacology
Published research examines Retatrutide activity at GIP, GLP-1, and glucagon receptors.
Triple GIPR / GLP-1R / GCGR agonist research overviewWhat is retatrutide? Structure and research recordComparative research
The research library
A closer look at the science.
Explore Retatrutide's identity, receptor activity, and published research.
Explore the research
Before you order
Buying Retatrutide — Frequently Asked Questions
What purity standard does Peptide.Express use for retatrutide?
Sourced to a ≥99% HPLC specification, measured as area-under-curve when a certificate reports it. Where a certificate reports a mass, compare it with 4,731 Da. For a compound in this regulatory category the analytics carry more weight than usual: there is no pharmacopoeial monograph and no reference standard, so the chromatogram and the mass spectrum are the evidence.
Where is the Certificate of Analysis for retatrutide?
On this page, in the certificate panel above for the size this page opens on, and in the Peptide.Express lab results library. Read Lot, accession, measured HPLC, and the testing laboratory from that panel — they are printed on the certificate for the selected size. Match the lot on the vial to the lot on the CoA. If you select a size with no certificate on file, that size has no lot document yet — do not use another size's CoA. A Certificate of Analysis is a batch record, not a product-line brochure. For laboratory research use only. Not for human or veterinary use.
What testing does retatrutide undergo before shipping?
Where a certificate is on file, it shows the assays that laboratory reported. Those can include reverse-phase HPLC, LC-MS/MS, an endotoxin result, and visual QC. A missing line is not a pass and is not proof the assay never ran.
How should retatrutide be stored before and after reconstitution?
Lyophilized: -20°C, desiccated and protected from light, stable for 24 months from manufacture. Reconstituted: 2–8°C, used within 14–28 days. Do not freeze the reconstituted solution. Acylated peptides aggregate under thermal cycling more readily than small unmodified ones, so repeated freeze-thaw is a real degradation route rather than a generic warning.
When do research-peptide orders ship?
US orders placed before 2 PM Eastern ship the same business day. Orders over $150 ship free inside the US. See the shipping page for the current policy. For laboratory research use only. Not for human or veterinary use.
Is retatrutide FDA approved?
No. Retatrutide is not approved by the FDA for any indication and is not approved by any other regulatory agency. This SKU is research-grade material. For in-vitro laboratory research use only. Not for human or veterinary use.
All products are sold for in vitro laboratory research use only. Not intended for human consumption, clinical use, or veterinary use. Peptide.Express makes no medical claims. Consult the published literature for research application guidance.
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Catalog identity reference
Theoretical identity from the catalog or verified registry record — not a laboratory observation from the Certificate of Analysis above.
- CAS Number
- 2381089-83-2
- Molecular Formula
- C221H342N46O68
- Molecular Weight
- 4731 g/mol
- Sequence
- YAQGTFTSDYSILLDKKAQAAFIEYLLEGGPSSGAPPPS (39 residues; Aib at 2 and 20, alpha-Me-Leu at 13, C20 fatty diacid on Lys17 via gamma-Glu/AEEA linker, C-terminal amide)
What we can show you the numbers for
- 25 Certificates of Analysis published.Verify with the issuing laboratory: BPC-157 · CJC-1295 + Ipamorelin (No DAC) · Epithalon · GHK-Cu · HCG · HGH · Ipamorelin · Kisspeptin-10 · KLOW Blend · KPV · Melanotan II · Mitochondrial Fuel Stack · MOTS-c · NAD+ · PT-141 · Retatrutide · Retatrutide Pen · Semax · Semax Nasal Spray · Sermorelin · SS-31 · TB-500 · Tesamorelin · Tirzepatide · Wolverine Blend.
- Orders after 2 PM EST may be processed the next business day
- Free US shipping on orders over $150
