Retatrutide dosing — research reference
Pre-clinical dose ranges and routes
Reviewed by the BestHealingPeptides Editorial Team ·
This page summarises the pre-clinical research dose ranges reported in the published literature for Retatrutide. The ranges shown are derived from rodent and other animal model studies and do not constitute a recommendation for human use. Retatrutide is not licensed as a medicine in the United Kingdom and may not be administered to humans outside an authorised clinical trial.
When interpreting the ranges below, three considerations dominate. First, dose conversion across species is not linear in either body weight or surface area for peptides; allometric scaling from rodent doses to human equivalents introduces substantial uncertainty. Second, route of administration materially affects pharmacokinetic exposure — subcutaneous, intraperitoneal, intramuscular, and oral routes have different bioavailability profiles for the same molecule. Third, batch-to-batch variability in research-chemical-grade peptide preparations means that nominal doses do not always correspond to actual delivered active peptide; Certificate of Analysis verification of HPLC purity and identity is essential before any in-vivo work.
For full mechanistic context, study summaries, and safety information, see the main Retatrutide research profile.
Reported routes of administration
- Subcutaneous injection (Phase III clinical trial route; not licensed)
Reported half-life
Approximately 144 hours (~6 days) plasma half-life through fatty-acid acylation supporting albumin binding. Similar dosing interval expectations to tirzepatide (once weekly) and semaglutide (once weekly). Phase III TRIUMPH programme is testing once-weekly subcutaneous administration.
See the dedicated half-life reference page for fuller pharmacokinetic context.
Reported pre-clinical dose ranges
| Model | Route | Reported range | Note |
|---|---|---|---|
| Phase II obesity trial (Jastreboff 2023) | Subcutaneous, once weekly | 1, 2, 4, 8, 12 mg/week with titration over 12-24 weeks to target dose | Dose-ranging Phase II protocol. The 12 mg dose produced the 24.2% mean weight loss; GI burden substantial at higher doses. |
| Phase II type-2 diabetes trial (Rosenstock 2023) | Subcutaneous, once weekly | 0.5, 4, 8, 12 mg/week with titration | Similar titration framework adapted for type-2 diabetes population. |
| Phase III TRIUMPH programme (ongoing) | Subcutaneous, once weekly | Dose tiers per indication; not yet finalised | Phase III is testing optimised doses informed by Phase II tolerability data. |
Practical research considerations
Selecting a research dose for Retatrutide should account for the route used in the source publication, the species and strain of the animal model, the experimental endpoint timepoint, and any vehicle effects. A common methodological error is to apply a rodent intraperitoneal dose to a subcutaneous protocol without route-correction, which materially over- or under-estimates exposure. For new research programmes, pilot dose-ranging studies with serial endpoint sampling are advised before committing to a single dose tier.
Reconstitution vehicle is a recurring source of inter-study variability. Bacteriostatic water with 0.9% benzyl alcohol is the standard research vehicle; sterile water for injection is the alternative where benzyl alcohol interferes with downstream assays. See the reconstitution reference page and the reconstitution master guide for protocol-level detail.
For safety considerations, contraindications, and known formulation interactions, see the safety reference page.
Where to source Retatrutide for laboratory research
The following UK-based suppliers stock research-grade, lyophilised peptides for in-vitro and pre-clinical work. Purity and provenance vary; always request a Certificate of Analysis (CoA) and confirm cold-chain storage on arrival. None of the products linked below are approved for human use.
- PeptideAuthority.co.uk
UK-based research peptide supplier with batch certificates of analysis and >99% purity testing.
- PeptideBarn.co.uk
Wide catalogue of research-grade lyophilised peptides shipped from the UK, including bulk vials.