Research timeline and gaps: Retatrutide: Clinical Weight Loss and Supply Claims

Selected publication milestones, not an exhaustive history or discovery priority claim.

2013 — Dual-incretin translational experiments establish alternative receptor architectures before retatrutide. Original PMID24174327.

2013 — Glucagon/FGF21genetic perturbation separates some weight/energy effects from glucose effects. Original PMID23305646.

2022 — LY3437943discovery combines receptor/mouse perturbation and early humanexposure/weight observations. Original PMID35985340.

2023 — Randomized phase2obesityweight efficacy demonstrated through48weeks. Original PMID37366315.

2023 — Randomized phase2T2Dtrial addsdulagutide active comparison and dose boundaries. Original PMID37385280.

2025 — Directtirzepatide-versus-semaglutide comparison demonstrates why head-to-headandcross-trialclaims differ. Original PMID40353578.

2025 — RetatrutideDXAbodycomposition substudypublished with missingness limits. Original PMID40609566.

2026 — 40-week retatrutide diabetesphase3report published with weight a secondaryendpoint. Original PMID42250575.

2026 — 29September2026TRIUMPH1reports80-week obesityweight and clinicalsubgroupoutcomes. Original PMID42814954.

2026 — 29September2026TRIUMPH2reports80-week weight efficacy inobesitywithT2D. Original PMID42810372.

Research gaps

Direct matched retatrutide versus modern obesity-dose semaglutide/tirzepatide superiority with comparable estimands and durability.

Retatrutide-specific withdrawal/rechallenge and long-term weight/function maintenance rather than class extrapolation.

Human contribution of each receptor at measured therapeutic exposure, including energy expenditure and intake partition.

Hard cardiovascular/renal outcomes and longer safety follow-up; surrogate lipid and inflammation analyses are insufficient.

Muscle strength/function and clinically important composition outcomes, withDXAmissingness disclosed.

Independent identified retatrutide supply-batch quality and product-linked clinical evidence; no assay result from semaglutide characterizes everyretatrutide vial.

Boundary experiment

A blinded randomized retatrutide versus contemporary obesity-dose dual/GLP1 comparator trial, matched eligibility, lifestyle support and treatment-regimen estimand over72weeks, with a prespecified retatrutide continuation-versus-withdrawal phase in baseline-defined tolerators and independent weight/function assessment. Add human energy-expenditure/intake/body-composition substudy without interpreting correlations as receptor necessity.