Evidence & concentration worksheet · Experimental Research
Retatrutide 30 mg
Controlled trials exist, but there is no approved consumer product or prescribing label. Trial doses apply only inside their monitored study designs, not to online research vials.
Evidence review
Investigational trial context — not self-use instructions
Controlled trials exist, but there is no approved consumer product or prescribing label. Trial doses apply only inside their monitored study designs, not to online research vials.
How it works
Retatrutide, also known by its development code LY3437943, is an investigational peptide-class "triple agonist" designed to activate three separate metabolic hormone receptors at once: GIP, GLP-1, and glucagon.[1] Eli Lilly is developing it for obesity, type 2 diabetes, and related metabolic conditions, but it is not an FDA-approved drug and has no approved prescription product on the market.
Retatrutide is often discussed alongside tirzepatide, a dual GIP/GLP-1 agonist, and semaglutide, a GLP-1-only agonist. Unlike those two, retatrutide remains in Phase 3 clinical trials rather than approved labeling, and its results should be read as investigational until regulators complete their review.[2]
Benefits & side effects
Retatrutide has produced large weight reductions in controlled metabolic trials. In a Phase 2 obesity trial, the highest-dose group had a mean reduction of roughly 24% at 48 weeks.[4] Eli Lilly's May 2026 TRIUMPH-1 topline release reported a mean reduction of about 28% at 80 weeks in the highest-dose efficacy estimand.[7] The Phase 3 result should remain identified as sponsor-reported topline evidence until a complete peer-reviewed report permits independent scrutiny; cross-trial comparisons are also unreliable because designs and populations differ.
Phase 2 and Phase 3 studies in type 2 diabetes reported dose-dependent HbA1c reductions, while a MASLD substudy reported reductions in liver fat.[5][6][8] These are investigational findings, not approved-label outcomes, and long-term cardiovascular and safety endpoints remain under evaluation.
Calculator
Concentration and measurement calculator
Use this only to check arithmetic from an authoritative product label, registered study protocol, or qualified clinician.
Arithmetic only — not a dose recommendation
Enter only a concentration and target supplied by an authoritative product label, a registered study protocol, or a qualified clinician. A correct conversion does not establish that a substance, vial, route, or dose is safe or effective.
Enter only a concentration and target supplied by an authoritative product label, a registered study protocol, or a qualified clinician. A correct conversion does not establish that a substance, vial, route, or dose is safe or effective.
Source concentration
Source-supplied target
References
References
- IUPHAR/BPS — Retatrutide ligand record (2026)
- Eli Lilly — What to know about investigational retatrutide (2026)
- U.S. FDA — Concerns with unapproved GLP-1 drugs used for weight loss (2026)
- New England Journal of Medicine — Triple-hormone-receptor agonist retatrutide for obesity: phase 2 trial (2023)
- The Lancet — Retatrutide phase 2 trial in type 2 diabetes (2023)
- Nature Medicine — Retatrutide substudy in metabolic dysfunction-associated steatotic liver disease (2024)
- Eli Lilly — TRIUMPH-1 phase 3 topline results (2026)
- The Lancet — Phase 3 retatrutide trial in type 2 diabetes (2026)
- Cell Metabolism — Preclinical pharmacology of LY3437943 (2022)
- Molecular Metabolism — GLP-1 physiology and obesity pharmacotherapy (2022)
- U.S. FDA — Current Wegovy prescribing information (2026)
- U.S. FDA — Current Zepbound prescribing information (2026)
- ClinicalTrials.gov — NCT06662383 retatrutide versus tirzepatide phase 3 trial (2026)