Retatrutide — Compound Overview
A researcher-focused overview of retatrutide: its chemistry as an engineered incretin-receptor peptide, its investigational status, and how each batch is documented.
What is retatrutide?
Retatrutide is a synthetic 39-residue modified peptide engineered to act as an agonist at three receptors: the glucose-dependent insulinotropic polypeptide (GIP) receptor, the glucagon-like peptide-1 (GLP-1) receptor, and the glucagon receptor. It is built on a GIP-like backbone with non-natural amino-acid substitutions and a C20 fatty-diacid moiety attached via a linker — a lipidation strategy used to extend peptide half-life.
Chemistry and structure
Retatrutide carries CAS registry number 2381089-83-2, molecular formula C221H342N46O68 and a molecular weight of approximately 4731.3 g/mol, making it by far the largest peptide in this catalogue. Its size and lipidation make manufacturing and analytical characterisation more demanding, which is reflected in batch-level documentation.
Regulatory status — read carefully
Retatrutide is an investigational compound in pharmaceutical clinical development. It is NOT an approved medicine anywhere in the world, and no compounded, 'generic' or research-chemical version of it is legal to use in humans. Index Peptides supplies retatrutide strictly for in-vitro laboratory research, with payment and listing reviews reflecting its higher-risk status. Support cannot discuss human use of any kind.
Retatrutide in the research literature
Retatrutide appears in the incretin-pharmacology literature as a multi-receptor agonist tool compound, alongside published clinical-trial reports concerning the pharmaceutical development programme. Those trials concern the sponsor's controlled pharmaceutical product — they do not validate research-grade material for any use beyond the laboratory.
Form, handling and storage
Supplied as a lyophilised powder in a sealed vial. Store at -20°C, desiccated and protected from light, per the batch record. Lipidated peptides can show different solubility behaviour from unmodified peptides; reconstitution conditions are part of the experimental design and are not advised by Index Peptides.
Batch documentation at Index Peptides
Every released batch is HPLC purity tested and LC-MS identity confirmed (expected versus detected mass), with the certificate of analysis published on the product page and verifiable by lot number.
Frequently asked questions
Is retatrutide an approved weight-loss drug?
No. Retatrutide is an investigational compound in clinical development and is not approved anywhere. The material here is for in-vitro laboratory research only — not for human use, and support cannot discuss human use.
Why is identity testing especially important for retatrutide?
At ~4.7 kDa with non-natural residues and a fatty-diacid modification, retatrutide is difficult to synthesise correctly. LC-MS identity confirmation (expected vs detected mass) on the COA is the check that the vial contains the right molecule.
Why is it invoice-only rather than card checkout?
Retatrutide is held to stricter payment and listing review because of its higher regulatory risk profile. Orders go through the invoice flow.
References
Research use only. Not for human or animal consumption.