Retatrutide (TRIPLE G)

Retatrutide serves as a tool in the pharmacology of incretin receptors and the glucagon receptor. Working concentrations are chosen by the researcher depending on the model; the subcategory gives no quantities and no schedules.

• In vitro receptor characterisation. Measurements of activity at GCGR, GIPR and GLP-1R allow a triple-receptor agonist to be compared with dual and single agonists in the same system (Coskun et al., 2022).
• Rodent models of energy metabolism. In obese mice the molecule reduced body weight and improved glycaemic control, and the authors attributed part of the effect to a glucagon-receptor-mediated increase in energy expenditure added to the reduction of calorie intake driven by the GIP and GLP-1 receptors (Coskun et al., 2022).
• Clinical data on the drug candidate. In a phase II trial in 338 adults the change in body weight at 48 weeks, reported as a least-squares mean, ranged from −8.7% to −24.2% across dose groups against −2.1% on placebo (Jastreboff et al., 2023, PMID 37366315). In the phase III TRIUMPH-1 trial in 2,339 adults with obesity and without diabetes, the change in body weight at 80 weeks was −17.6%, −23.7% and −25.0% in the three dose groups against −3.9% on placebo, under a treatment-regimen estimand (Jastreboff et al., 2026, PMID 42814954).
• Populations with type 2 diabetes. TRIUMPH-2 enrolled 1,152 adults with obesity and type 2 diabetes at 92 centres across eight countries (Bellido et al., 2026, PMID 42810372), while TRANSCEND-T2D-1 enrolled 537 people in whom glycated haemoglobin changed by −1.69, −1.86 and −1.94 percentage points at 40 weeks against −0.81 on placebo, again under a treatment-regimen estimand (Bajaj et al., 2026, PMID 42250575).
• Identity analytics. Confirming the mass and sequence of a 39-residue peptide and separating it from agonists with a shorter backbone, by HPLC and mass spectrometry.

Scientific perspective. The clinical figures relate to a drug candidate studied under medical supervision, in defined populations and under a stated estimand. A 2026 review notes that values from sponsor disclosures calculated under an efficacy estimand are higher than those under a treatment-regimen estimand, and that population differences and treatment discontinuation also matter to interpretation (Mateescu et al., 2026). A research reagent is not that drug candidate, and the results of those trials do not apply to it.

How retatrutide differs from related compounds

By receptor scope within the family. Semaglutide, listed in the catalogue as SEMA G, activates one receptor, GLP-1. The GLP-1 + GIP reagent activates two, GLP-1R and GIPR. Retatrutide adds the glucagon receptor to those, so it acts through three. The distinction describes the profile of the molecule in models, not an advantage over the others.

By form, not by molecule. A vial of lyophilisate and a PEN applicator contain the same peptide. Lyophilisate lets the researcher set the concentration of the stock solution to suit the experimental system, while the factory solution has a concentration set by the manufacturer and declared in the batch documentation. The choice between them follows from the methodology of the protocol.

Regulatory status and anti-doping note

Retatrutide holds no marketing authorisation as a medicine in any jurisdiction. The European Medicines Agency data on products authorised in the member states (Article 57, as of 9 October 2026) contain no entry for this substance, and the Drugs@FDA database holds no product with it as an active ingredient (checked 8 November 2026). There is no authorisation as a food or dietary supplement ingredient in the European Union either.

Anti-doping note. The WADA Prohibited List 2026 does not name retatrutide, and neither does the 2027 List, which applies from 1 January 2027. In both editions the decisive provision is category S0: it covers any pharmacological substance that no governmental regulatory health authority has approved for human therapeutic use, including substances under clinical development. Retatrutide meets that condition, so it falls under category S0 and is prohibited at all times, in and out of competition. The binding sources are the List in force and the ADAMS system, so researchers and athletes verify the status themselves. Materials from this subcategory are research reagents and do not serve as preparation for sporting competition.

What is retatrutide, and why is it called TRIPLE G in the catalogue?

Retatrutide (LY3437943) is a lipidated 39-residue peptide, an agonist of the GIP, GLP-1 and glucagon receptors. TRIPLE G is the trade name of the reagent line and refers to the three target receptors; the substance is the same.

How does a vial of lyophilisate differ from a PEN applicator?

By the physical state of the material. Lyophilisate is a dry powder that the researcher reconstitutes, thereby setting the concentration of the stock solution. A PEN holds a solution at a concentration set at the factory and declared on the label and in the batch certificate of analysis. The molecule is identical in both variants.

Is a reagent from this subcategory a medicine for obesity or diabetes?

No. Retatrutide holds no marketing authorisation as a medicine anywhere, and the materials in this subcategory are reagents for laboratory research. Results from clinical trials of the drug candidate do not apply to a reagent.

How can the identity of a multi-receptor peptide be confirmed?

By mass and sequence in the batch certificate of analysis. For dual and triple agonists a trade name does not establish the structure; confirmation by mass spectrometry and the HPLC result decide the matter.

Is retatrutide prohibited in sport?

Yes. It is not named in the 2026 List or the 2027 List, but as a substance with no approval for human use it falls under category S0 in both editions, prohibited at all times.

Category status notice

This category groups chemical reagents intended solely for laboratory research (Research Use Only). The peptides collected here are not medicinal products, dietary supplements or foodstuffs. They are not intended for use in humans or animals. Sales are restricted to registered research institutions and laboratories.