Retatrutide (LY3437943) is an investigational triple GIP/GLP-1/glucagon receptor agonist in Phase 3 clinical trials. Available as a research peptide from Eternal Peptides Wholesale for laboratory use only.

Is retatrutide available in Australia for research?

Retatrutide is available as a research peptide from Eternal Peptides Wholesale (10mg and 20mg vials, Janoshik COA-verified). For qualified laboratory research use only — not approved for human therapeutic use in Australia.

Retatrutide Research Overview: Triple Receptor Agonist

Retatrutide: Triple Receptor Agonism and Phase 3 Clinical Development

A summary of published research on retatrutide (LY3437943), a synthetic peptide under Phase 3 investigation as the first triple GIP/GLP-1/glucagon receptor agonist in clinical trials. For research purposes only — not for human therapeutic use.

Eternal Peptides Wholesale Research Team

Published 27 April 2026 · Updated September 2026 · For research use only

What Is Retatrutide?

Retatrutide (LY3437943) is a synthetic peptide developed by Eli Lilly and studied as an agonist at GIP, GLP-1 and glucagon receptors. Its receptor mechanism and clinical development are described in the studies cited below.

Triple Receptor Mechanism

GLP-1R Agonism

GLP-1 receptor activation is involved in glucose-dependent insulin secretion, glucagon regulation, gastric emptying and energy intake.

GIPR Agonism

GIP receptor activity is studied in insulin secretion and adipose-tissue metabolism.

GCGR Agonism — The Distinguishing Mechanism

Glucagon receptor activity is studied in hepatic glucose regulation and energy metabolism. The net effects of a multi-receptor agonist must be established experimentally.

Phase 2 Published Data

Results published in the New England Journal of Medicine (Jastreboff et al., 2023) from a randomised Phase 2 trial across dose cohorts (1mg, 4mg, 8mg, 12mg once weekly) showed:

~24% mean body weight reduction from baseline at 48 weeks in the highest dose cohort
Dose-dependent reductions in liver fat fraction (MRI-PDFF), triglycerides, and systolic blood pressure
Adverse events consistent with GLP-1 class — predominantly gastrointestinal, dose-dependent

Source: Jastreboff AM et al. N Engl J Med. 2023;389(6):514-526. Phase 2 data only.

Phase 3 Programme: TRIUMPH Trials

TRIUMPH-1: evidence update, 29 September 2026

Lilly presented TRIUMPH-1 Phase 3 results at the ADA Scientific Sessions on 6 June 2026, with an 80-week primary assessment and a 104-week extension. These findings are separate from the 2023 Phase 2 study and do not establish equivalence of separately supplied research materials.

Source: Lilly: TRIUMPH-1, ADA 2026. Consult individual trial records for other populations and endpoints; this is not a complete programme inventory.

Available for Laboratory Research

For practical sourcing checks, see our guide to Retatrutide suppliers and laboratory reports.

Eternal Peptides Wholesale is one of Australia's only dedicated wholesale research peptide distributors supplying Janoshik-verified Retatrutide for laboratory research.

Retatrutide is available as a research peptide from Eternal Peptides Wholesale. All batches are submitted to Janoshik Analytical for third-party HPLC purity verification, sterility testing, endotoxin testing, and heavy metals analysis.

Retatrutide 10mg — View Product Retatrutide 20mg — View Product

Frequently Asked Questions

What is retatrutide?

Retatrutide (LY3437943) is an investigational triple GIP/GLP-1/glucagon receptor agonist in Phase 3 clinical trials. It is the first triple incretin agonist to enter large-scale trials. Available as a research peptide from Eternal Peptides Wholesale for qualified laboratory use only.

Is retatrutide approved for use in Australia?

No. As of 2026, retatrutide has not received TGA registration. It is available as a research peptide for qualified laboratory research purposes only — not for human therapeutic use.

Where can I source retatrutide for research in Australia?

Retatrutide (10mg and 20mg per vial, box of 10) is available wholesale from Eternal Peptides Wholesale with full Janoshik COA documentation. For qualified laboratory research use only.

Key References

Source: Jastreboff AM et al. N Engl J Med. 2023;389(6):514-526. PMID: 37366315

Jastreboff AM et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity. N Engl J Med. 2023;389(6):514-526.
Coskun T et al. LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist. Cell Metab. 2022;34(9):1234-1247.
ClinicalTrials.gov. TRIUMPH-1: NCT05882045.

Research Use Disclaimer: All content is derived from published peer-reviewed literature and public clinical trial registries. Products sold by Eternal Peptides Wholesale are for qualified laboratory research use only and are not intended for human therapeutic use or consumption.

Key Takeaways At a Glance

✓Retatrutide (LY3437943) is a synthetic peptide and the first triple GIP/GLP-1/glucagon receptor agonist to enter Phase 3 clinical trials
✓Phase 2 data (Jastreboff et al., NEJM 2023): ~24% body weight reduction at 48 weeks in highest dose cohort — a within-group baseline change, not proof of comparative superiority
Retatrutide combines activity at GIP, GLP-1 and glucagon receptors.
✓TRIUMPH-1 Phase 3 results were presented in June 2026; its 80-week primary assessment and 104-week extension are distinct from Phase 2 results
✓Not TGA-approved in Australia as of 2026; available as a research peptide from Eternal Peptides Wholesale for qualified laboratory use only

Testing and wholesale procurement: source notes

Assess purity separately from peptide quantity. Bachem explains that HPLC purity and net peptide content describe different properties. For an EPW procurement review, start with the published report directory, then match the product, strength and batch to the documents. ^[1] ^[2]

Our testing programme addresses purity, endotoxins, sterility testing (TAMC/TYMC microbial screening) and heavy metals. Janoshik describes the microbial, endotoxin and metals analyses as separate services; the actual report determines the tests and results applicable to a sample. A general programme description is not a claim that every item has all four reports. ^[3] ^[4] ^[5]

For wholesale value, compare the same specification and quantity, then check the total payable. The wholesale-price guide explains the method. Reports do not establish therapeutic approval or a legal exemption; the TGA explains that research-use wording alone does not remove applicable obligations. ^[6] ^[7]