Retatrutide in Canada: where the research stands

Retatrutide is not approved for any use in Canada, the United States or anywhere else. It is an investigational peptide developed by Eli Lilly, and as of November 2026 it is still being studied in phase 3 trials. This page sets out what has been published, where the trials ran, and what "not approved" means.

What retatrutide is

A single synthetic peptide that activates three receptors: GIP, GLP-1 and glucagon. Our explainer, what is retatrutide, covers the structure, and retatrutide vs tirzepatide compares it with the dual agonist.

What the trials measured

• Phase 2 (2023): Jastreboff and colleagues randomised 338 adults with obesity to retatrutide or placebo for 48 weeks and reported the change in body weight (N Engl J Med, 2023).
• Phase 3, TRIUMPH-1 (2026): 2,339 adults with obesity and without diabetes, 80 weeks, three dose levels against placebo (N Engl J Med, 2026).
• Phase 3, TRIUMPH-2 (2026): 1,152 adults with obesity and type 2 diabetes, same design (The Lancet, October 2026).

Our research roundup of 20 October gives the measured outcomes and adverse events of both phase 3 papers.

Trials in Canada

Several retatrutide trials have enrolled at Canadian hospitals and clinics; one cardiovascular study alone lists 17 Canadian sites (ClinicalTrials.gov NCT05882045). Registered trials are the only authorized way retatrutide is given to people in Canada.

Approval status

A drug is approved in Canada only after Health Canada reviews a submission from its manufacturer. Health Canada has not authorized retatrutide, and its April 2026 advisory on peptides bought online names it among unauthorized products.

Ordering retatrutide for laboratory research

Peptune supplies retatrutide as a lyophilized reference material for in vitro and analytical work, with the batch certificate on the product page. Orders ship across Canada by tracked mail: $20 or $25 depending on the province, free on orders of $150 or more. Payment is by Interac e-Transfer or crypto.

For laboratory research use only. Not for human or veterinary use. Nothing here is medical advice.