Retatrutide
Also known as triple agonist, GIP/GLP-1/glucagon receptor agonist, LY3437943
Retatrutide is an investigational single-molecule triple receptor agonist (GIP/GLP-1/glucagon) studied as a research compound. Its research-use profile: the tri-agonist design and handling.
Retatrutide is the most structurally ambitious member of the incretin-analog family covered on this store. Where single agonists target one receptor and dual agonists two, retatrutide is engineered so that a single peptide acts at three: the GIP receptor, the GLP-1 receptor, and — the addition that sets it apart — the glucagon receptor.
It is an investigational molecule, not an approved one, and this monograph treats it with the same restraint as the rest of the cluster. It states the molecular class and the tri-agonist architecture only. No therapeutic, metabolic-outcome, dosing, or efficacy claims are made or implied; the compound is presented purely in a research-use context.
An investigational synthetic peptide engineered to engage three receptors from one backbone: the GIP receptor, the GLP-1 receptor, and the glucagon receptor. It belongs to the acylated long-acting incretin-analog family, but its defining trait is the number of receptor targets — three — rather than any single structural modification. Described strictly as a research compound.
The third receptor: glucagon
GIP and GLP-1 are the two incretin receptors already familiar from dual agonists. Retatrutide adds a third target — the glucagon receptor — into the same molecule. That is the single fact that most distinguishes it structurally from tirzepatide, and it is why the literature calls it a triple agonist or tri-agonist.
Adding glucagon-receptor activity is a meaningfully different design choice than simply extending half-life or stacking two incretins, which is why retatrutide is studied as its own comparison point rather than as a variant of the dual agonists.
Reading it within the agonist ladder
A clean way researchers organize this space is as a ladder: single-target GLP-1 agonists, dual GIP/GLP-1 agonists, then triple GIP/GLP-1/glucagon agonists. Retatrutide occupies the top rung. Placing it next to semaglutide (single) and tirzepatide (dual) lets a study isolate what each added receptor target contributes to a molecule's profile in a model.
Because it is investigational, published descriptive information is more limited than for approved analogs, so this page keeps strictly to what is well established: its class, its three receptor targets, and how such a compound is handled.
These are research areas the compound is associated with in the literature — not medical claims or intended uses.
Handling & storage
Supplied lyophilized. Kept sealed and cold, reconstituted only when a research protocol requires it and then refrigerated. Handled per accepted laboratory practice for acylated peptide analogs. Research use only.
Verify a certificate by lot →Common questions
The GIP receptor, the GLP-1 receptor, and the glucagon receptor — engaged from a single peptide backbone, which is why it is called a triple agonist. This is a molecular-class description, not a use claim.
Tirzepatide is a dual GIP/GLP-1 agonist; retatrutide adds a third target, the glucagon receptor, making it a tri-agonist. That extra receptor is its defining structural distinction.
It is investigational rather than approved. This monograph describes only its well-established molecular class and design, in a research-use context.
This monograph is a research-use reference. It describes composition and the contexts in which the compound has been studied — it is not medical advice, a description of effects, or a recommendation for use. Sold strictly for laboratory and research use; not for human or animal consumption.