Retatrutide | Triple Receptor Research Peptide

Description

What is retatrutide?

Retatrutide (LY3437943) is an investigational peptide developed by Eli Lilly. It is not FDA-approved. Peptryn supplies it as a lyophilized laboratory material in 10mg, 30mg and 60mg vials. The molecular weight is about 4,731 Da and the CAS number is 2381089-83-2.

Before you order any retatrutide, read our checklist for buying retatrutide for research. It covers what a real lot report shows and the red flags to look for.

Retatrutide specifications

Compound	Retatrutide (LY3437943)
Sizes	10mg, 30mg, 60mg
Form	Lyophilized powder
Molecular weight	About 4,731 Da
CAS number	2381089-83-2

Lot testing and COA

Two reports are published, each tied to a lot. Retatrutide 10mg, lot 2026-06-12, reads 99.62% purity by HPLC-UV-MS with a negative endotoxin result. Retatrutide 30mg, lot 2026-08-31, reads 99.32% purity with identity confirmed by mass spectrometry. MZ Biolabs did the testing and each certificate links to the laboratory’s own report. For the 60mg size, email [email protected] with your order number and we send the report on file.

Retatrutide 10mg COA · Retatrutide 30mg COA · COA Library

Ordering

Orders placed on peptryn.com ship from the USA with same-day dispatch, and shipping is free on orders over $150. For a question about a lot or a size, email [email protected].

Storage

Store lyophilized powder at -20°C, protected from light and repeated freeze-thaw cycles.

Frequently asked questions

What is retatrutide?

Retatrutide (LY3437943) is an investigational peptide developed by Eli Lilly, about 4,731 Da. It is not FDA-approved. Peptryn supplies it as a lyophilized laboratory material in 10mg, 30mg and 60mg vials.

What purity is Peptryn’s retatrutide?

Peptryn’s retatrutide is verified at 99.62% purity (10mg lot, 2026-06-12) and 99.32% purity (30mg lot, 2026-08-31), tested by MZ Biolabs. 10mg COA · 30mg COA. HPLC purity is area percent, the share of the main peak among all detected peaks; see our guide to peptide purity for what that means.

How is retatrutide stored?

Store lyophilized powder at -20°C, protected from light and repeated freeze-thaw cycles.

What is retatrutide’s CAS number?

Retatrutide’s CAS number is 2381089-83-2. Molecular weight: About 4,731 Da.

Is retatrutide for human use?

No. Peptryn sells it for laboratory research only, and it is not approved for human or veterinary use. We do not give dosing or administration guidance.

Is retatrutide FDA approved?

No. Retatrutide is investigational. Eli Lilly has said it expects to submit for FDA approval in the first quarter of 2027. See our guide to buying retatrutide for research for the source.

How is retatrutide different from semaglutide and tirzepatide?

Semaglutide (sold as Ozempic and Wegovy) and tirzepatide (sold as Mounjaro and Zepbound) are FDA-approved drugs. Retatrutide is a different, investigational molecule and is not approved for any use.

Related: Buying retatrutide for research · Retatrutide FDA approval status · Retatrutide vs semaglutide and tirzepatide · Retatrutide’s half-life · What is a COA? · Peptide testing · Popular peptides · Cagrilintide vs retatrutide

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For laboratory research use only. Not for human or veterinary use, and not a drug, food, dietary supplement or cosmetic. You must be 21 or older to buy.