What is the evidence behind Retatrutide?

Evidence grade B. See our grading methodology for what each grade means.

Is Retatrutide available in 2026?

Not available to prescribe. Retatrutide is an investigational drug in Phase-3 trials (Eli Lilly), not FDA-approved, not compoundable, and heavily counterfeited on the grey market. We track it and capture demand honestly; we make no availability promise.

Is Retatrutide FDA-approved?

See the status line above. Compounded and investigational medications are not FDA-approved.

Peptide Knowledge Base · Metabolic

Retatrutide: what it is, what the evidence says, and its real status

Short version

An investigational triple GLP-1/GIP/glucagon agonist posting the largest weight-loss numbers recorded so far.

Join waitlistEvidence grade B · Good human evidence

That’s the honest answer. Everything below is the detail.

The molecule the metabolic world is watching hardest.

Can you actually get it?

Plain-English verdict: Join waitlist.

Regulatory status: Investigational (Phase 3).

How does Retatrutide work?

A single molecule agonizing three receptors, GLP-1, GIP, and glucagon, combining appetite suppression with an added energy-expenditure signal from glucagon.

What it does — and what it does not do

What it does: In trials, drives the largest average body-weight reduction seen to date for the class (reported ~24–29%).

What it does not do: It is not a guaranteed result; trial figures are not a promise and grey-market product is unverified and unsafe.

How honest is the evidence?

Evidence grade B — Good human evidence.

large Phase-3 trial data (TRIUMPH), figures pending peer review; re-verify

A grade measures how much human evidence exists, not whether a molecule is good, safe, or worth your interest. Read our grading methodology for what each grade means.

What we still don't know: Long-term safety and durability are not yet established; the trial program is ongoing and figures may change at peer review and approval.

WADA status: Not prohibited.

How it is taken

What the literature reports: subcutaneous, weekly, titrated. Educational only, no dose figures, never an instruction to self-administer.

Who should not take it

Investigational, full safety profile not characterized. Medullary thyroid carcinoma / MEN-2 signal class-wide; pregnancy. Clinician-gated.

Sources

Jastreboff et al., retatrutide Phase-2 (NEJM 2023) · TRIUMPH Phase-3 program (ongoing, re-verify against primary sources)

Compounded medications are not FDA-approved. We keep two signals separate and never collapse them: whether you can get something, and what the rule currently says. See the live FDA Peptide Tracker for status.

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Last reviewed Jun 18, 2026 · Peptós.LIFE · Not medical advice.

Cite this page

Retatrutide. Peptós.LIFE Peptide Knowledge Base. Reviewed Jun 18, 2026. https://peptos.life/peptides/retatrutide

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