In brief
LY3437943, later named retatrutide, is one peptide that activates three receptors: glucagon, GIP and GLP-1. In cell assays it showed balanced activity at the glucagon and GLP-1 receptors and more at the GIP receptor. In obese mice it reduced body weight and improved glycaemic control, and the authors attribute the extra weight loss over dual agonists to glucagon-receptor-driven energy expenditure added to the intake reduction from GIP and GLP-1 signalling. In a phase-1 single-ascending-dose study, safety and tolerability were similar to other incretin drugs, the pharmacokinetics supported once-weekly dosing, and a reduction in body weight persisted to day 43 after one dose. The authors conclude further clinical assessment is warranted.
Study design
Discovery-to-clinic paper for LY3437943: receptor pharmacology, obese-mouse studies and a phase-1 single-ascending-dose study.
What it does not show
A single-dose first-in-human study alongside mouse work, written by the developer. The phase-2 trials cited with it are where the weight and glucose results in people come from.
A clinical trial tests a pharmaceutical form of a compound, in a defined patient group, under medical supervision, with a defined endpoint. None of that transfers to a research-grade vial, and this page does not suggest it does.
Where this paper is cited
- Retatrutide — The discovery paper: how the three receptor activities were balanced in one molecule, with first-in-human data supporting once-weekly dosing.
Other papers cited for Retatrutide
- Study in humans Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial Jastreboff et al. (2023), N Engl J Med
- Study in humans 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 Rosenstock et al. (2023), Lancet
Further reading
- Research library: every paper cited on this site, by compound and by study type.
- GLP-1 family comparison
- How to read a certificate of analysis
- Lyophilised peptide storage and stability
How this page was made: the citation was retrieved from PubMed by PMID and checked against the title on the product page; the summary was written from the paper's abstract and reports only what the abstract reports. Read the paper itself before relying on any figure here.