Is retatrutide approved in Canada?
No. Retatrutide is not authorized by Health Canada and has no Drug Identification Number (DIN); no regulator anywhere has approved it. Eli Lilly has reported phase 3 obesity results and plans to file with the US FDA in the first quarter of 2027; no Canadian submission appeared on Health Canada’s list of drug submissions under review as of August 31, 2026. Health Canada’s April 2026 advisory, Think twice before injecting peptides bought online, names retatrutide among unauthorized injectable peptide drugs it has seized and says that “For Research Use Only” labelling does not make such products legal or exempt from regulatory requirements. Pure Peptides Canada supplies retatrutide only as a laboratory reagent for in-vitro research, not for human or veterinary use; see what a DIN number means.
Retatrutide (development code LY3437943) is an investigational peptide from Eli Lilly that activates three receptors at once: the GIP, GLP-1 and glucagon receptors. That “tri-agonist” profile is what distinguishes it from tirzepatide, which acts at GIP and GLP-1 receptors, and semaglutide, which acts at GLP-1 receptors only. This page covers it as a laboratory research reagent only.
Retatrutide at a glance
| Property | Detail |
|---|---|
| Developer code | LY3437943 (Eli Lilly) |
| Molecule type | Synthetic lipidated peptide |
| Receptor activity | Agonist at GIP, GLP-1 and glucagon receptors (tri-agonist) |
| Development status | Investigational; phase 3 obesity results reported in 2025–2026 (TRIUMPH trials); not approved in Canada or anywhere else |
| Research form | Lyophilized powder in sealed vials |
Results from retatrutide’s phase 3 program are now being reported. For what the TRIUMPH obesity trials found, see retatrutide phase 3 results.
Retatrutide vs tirzepatide vs semaglutide
| Retatrutide | Tirzepatide | Semaglutide | |
|---|---|---|---|
| Receptor targets | GIP + GLP-1 + glucagon | GIP + GLP-1 | GLP-1 |
| Agonist class | Tri-agonist | Dual agonist | Single-receptor agonist |
| Developer | Eli Lilly (LY3437943) | Eli Lilly (LY3298176) | Novo Nordisk |
| Status | Investigational | Marketed prescription drug products exist | Marketed prescription drug products exist |
| Research reagent | Retatrutide | Tirzepatide | Semaglutide |
The reagents listed here are lyophilized laboratory materials. They are not the branded prescription drug products, and they are not for human or veterinary use.
Why the glucagon receptor matters in research
GLP-1 and GIP receptor agonism are both incretin-pathway mechanisms. Adding glucagon-receptor agonism brings in a pathway associated with hepatic glucose output and energy expenditure, which is why tri-agonists are studied as a distinct class rather than as a stronger version of a dual agonist. In-vitro work typically compares activation of the three receptors — for example, cAMP signalling in receptor-expressing cell lines — or uses these compounds as standards for analytical method development.
How to verify a retatrutide batch
- Identity by mass spectrometry — compare the observed mass with retatrutide’s theoretical mass. Lipidated incretin peptides of similar size, such as tirzepatide, have different masses, so identity data is what tells them apart.
- Purity by HPLC — read the chromatogram, not only the headline figure; the HPLC testing guide explains how.
- Batch match — the certificate’s lot number must match the vial. Janoshik reports for retatrutide, tirzepatide and semaglutide are listed on the lab testing page.
- Read the whole report — test date, method and sample description matter as much as the purity number. See how to read a peptide COA.
Storage and handling
Keep sealed lyophilized vials cold, dry and away from light, warm a vial to room temperature before opening, and aliquot reconstituted stock to limit freeze-thaw cycles. See the peptide storage guide.
Sourcing retatrutide in Canada
Pure Peptides Canada supplies retatrutide as lyophilized research vials, alongside tirzepatide, semaglutide and other metabolic-research peptides, shipped tracked from within Canada with batches matched to independent Janoshik reports.
Research-grade retatrutide, batch-tested
HPLC purity and mass-spec identity from Janoshik, matched to your lot. Tracked shipping across Canada.
Frequently asked questions
What is retatrutide?
An investigational lipidated peptide (LY3437943) developed by Eli Lilly that acts as an agonist at the GIP, GLP-1 and glucagon receptors.
What is the difference between retatrutide and tirzepatide?
Tirzepatide activates two receptors (GIP and GLP-1). Retatrutide activates those two plus the glucagon receptor, which makes it a tri-agonist. They are different molecules with different masses.
When could retatrutide be approved in Canada?
No date is known. Eli Lilly plans to file with the US FDA in the first quarter of 2027, and Health Canada’s list of drug submissions under review included no retatrutide submission as of August 31, 2026. Approval decisions and timelines rest with regulators. Pure Peptides Canada sells retatrutide only as a laboratory research reagent, not for human use.
Do you provide dosing or administration information?
No. Retatrutide is supplied strictly for in-vitro laboratory research. We can answer questions about molecular identity, storage and analytical documentation.
For laboratory and research use only. Not for human or veterinary use, consumption, or administration. Nothing on this page is medical advice or a claim that any compound diagnoses, treats, cures, or prevents any condition. Purchasers confirm they are qualified to handle research materials and are of legal age in their province.
References
- Jastreboff AM, Kaplan LM, Frías JP, Wu Q, Du Y, Gurbuz S, et al. Triple-hormone-receptor agonist retatrutide for obesity — a phase 2 trial. New England Journal of Medicine. 2023;389(6):514–526. Randomized, double-blind, placebo-controlled phase 2 trial in 338 adults; it describes retatrutide (LY3437943) as a single peptide conjugated to a fatty diacid, with agonist activity at the GIP, GLP-1 and glucagon receptors.
- Rosenstock J, Frias J, Jastreboff AM, Du Y, Lou J, Gurbuz S, et al. Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-controlled, parallel-group, phase 2 trial conducted in the USA. The Lancet. 2023;402(10401):529–544. Phase 2 trial in 281 adults with type 2 diabetes that compared retatrutide with placebo and with dulaglutide, a GLP-1 receptor agonist, using change in HbA1c as the primary measure.
- Bajaj HS, Welch M, Shah P, Luna E, Jaouimaa FZ, Liu B, et al. Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial. The Lancet. Published online June 6, 2026. A 40-week, placebo-controlled phase 3 trial in 537 adults with type 2 diabetes, with change in HbA1c as the primary measure.
- Coskun T, Sloop KW, Loghin C, Alsina-Fernandez J, Urva S, Bokvist KB, et al. LY3298176, a novel dual GIP and GLP-1 receptor agonist for the treatment of type 2 diabetes mellitus: from discovery to clinical proof of concept. Molecular Metabolism. 2018;18:3–14. Discovery report for tirzepatide (LY3298176), a fatty-acid-modified dual GIP and GLP-1 receptor agonist, characterized in receptor-expressing cell lines and mouse studies before early clinical studies.
- Jakubowska A, le Roux CW, Viljoen A. The road towards triple agonists: glucagon-like peptide 1, glucose-dependent insulinotropic polypeptide and glucagon receptor — an update. Endocrinology and Metabolism. 2024;39(1):12–22. Review of GLP-1, GIP and glucagon receptor biology and of multi-receptor agonists including retatrutide, covering glucagon’s roles in hepatic glucose output and energy expenditure.
