Retatrutide

Retatrutide (LY3437943) is a 39-amino-acid synthetic peptide engineered as a balanced tri-agonist of the GLP-1, GIP and glucagon receptors. In preclinical literature it is used to model incretin signalling, energy expenditure and hepatic lipid handling. FAB Research supplies it as a pre-filled, pre-calibrated research pen: a sterile solution in a metered-dose device, removing reconstitution variability from in-vitro workflows.

Sequence YXQGTFTSDYSIXLDKKAQXAFIEYLLEGGPSSGAPPPS (modified)

Retatrutide is a synthetic peptide engineered for agonist activity at the GIP, GLP-1 and glucagon receptors, with acylation supporting an extended half-life. Research describes the incretin arms as contributing glucose-dependent insulin secretion, glucagon suppression and satiety signalling, while glucagon receptor agonism is investigated for effects on hepatic substrate handling and energy expenditure. The balance between glucagon receptor activity and the counter-regulatory effects of the incretin arms is the central design question in the published mechanistic work, and remains incompletely resolved. The glucagon arm is the principal distinguishing feature separating Retatrutide from dual GLP-1/GIP agonists.

The published record is limited to early and mid-stage clinical work and supporting preclinical studies; long-term characterisation does not yet exist. Phase 2 clinical research reported on metabolic and body composition endpoints. Triple-agonism mechanistic work examined receptor balance and the contribution of the glucagon arm relative to the incretin components. Energy expenditure investigations examined thermogenic and hepatic substrate effects attributed to glucagon receptor signalling. Comparative studies positioned the compound against dual-agonist (GLP-1/GIP, GLP-1/glucagon) and single-agonist designs. Evidence maturity note: Retatrutide is an early-stage investigational compound within an active patent landscape; no regulatory approvals exist and long-term safety data are absent.

• 5 mg per application (one metered dose)
• 4 doses per pen (20 mg total)
• Pre-filled sterile solution — no reconstitution step required
• Replace cap securely after each application; store refrigerated between uses

Storage: Store refrigerated at 2–8 °C in the original sealed box. Do not freeze. Protect from light.

• For in-vitro laboratory and preclinical research only — not for human or animal administration
• Tri-agonist mechanism (GLP-1 / GIP / glucagon): studies requiring receptor-specific endpoints must account for all three pathways with appropriate controls
• Investigational compound — no regulatory approval in any jurisdiction; long-term safety data absent from the published literature
• Active patent landscape: co-research publications may be subject to Eli Lilly IP review

• Phase 2 NEJM (Jastreboff et al., 2023): nausea (~42%), vomiting (~20%), diarrhoea (~13%), constipation — GLP-1 receptor class effects, dose-dependent and typically transient
• Decreased appetite — consistent with GLP-1 and GIP receptor agonism
• Injection site reactions: transient erythema, bruising
• Resting pulse rate elevation (~2–3 bpm above placebo in Phase 2 data)
• No significant cardiac, hepatic or renal safety signals at Phase 2 dose ranges

Effects listed are observations from published research literature and are not predictions for any specific use. All FAB Research products are for in-vitro laboratory research — not for human or animal administration.