FOXO4-DRI half-life & pharmacokinetics

Reported half-life

Extended plasma stability versus L-amino-acid peptides through D-amino-acid composition and retro-inverso architecture that confer near-complete peptidase resistance. Precise pharmacokinetic parameters incompletely characterised in the published literature but substantially longer than equivalent L-peptides.

The half-life and pharmacokinetic profile of FOXO4-DRI reported above is drawn from the published pre-clinical literature. Plasma half-life describes the time taken for the circulating concentration to fall by half after a single dose; tissue half-life — which may be longer for peptides retained in specific organs or matrices — is a distinct and often more relevant parameter for healing research, where the duration of exposure at the injury site matters more than the systemic exposure profile.

Routes of administration studied

• Intraperitoneal injection (pre-clinical rodent research)
• Intravenous infusion (pre-clinical research)
• Subcutaneous injection (research)

Different routes produce materially different pharmacokinetic profiles for the same peptide. Subcutaneous administration generally produces flatter, more sustained plasma profiles than intravenous bolus dosing; intraperitoneal administration (common in rodent models) is not directly translatable to human routes; oral administration faces the additional challenge of luminal and brush-border peptidase degradation, which is why most research peptides have very low oral bioavailability without protective formulation.

Drug class

Synthetic D-amino-acid retro-inverso peptide; senolytic compound targeting the FOXO4-p53 protein-protein interaction specifically maintained in senescent cells.

Mechanism context

Half-life interpretation depends on the underlying mechanism. FOXO4-DRI acts as follows:

FOXO4-DRI is a synthetic D-amino-acid peptide developed by Peter de Keizer's laboratory at Utrecht University as a targeted senolytic — a compound designed to selectively kill senescent cells while sparing healthy cells. The molecular design exploits the specific dependence of senescent cells on the interaction between the forkhead transcription factor FOXO4 and the tumour-suppressor protein p53. In healthy cells, FOXO4 and p53 have roles in cell-cycle regulation and stress response; in senescent cells, these two proteins form a specific complex that prevents senescent-cell apoptosis and enables the persistence of senescent cells in tissues. Senescent cells contribute to age-related tissue dysfunction through secretion of the senescence-associated secretory phenotype (SASP) — pro-inflammatory cytokines, matrix-degrading enzymes, and growth factors that promote adjacent-tissue dysfunction and inflammation.

See the full FOXO4-DRI research profile for the complete mechanism summary, history, study citations, and references.

Practical considerations

Short plasma half-life does not necessarily mean short duration of biological effect. Many peptides — including BPC-157, GHK-Cu, and the thymosin-derived compounds — exhibit tissue retention or mechanistic effects (gene expression, signalling cascades) that outlast plasma exposure by hours to days. The pharmacological half-life and the biological-effect half-life are distinct parameters that must both be specified in any rigorous research design. Repeated-dose protocols should account for accumulation only where tissue half-life is genuinely long; for most peptides with short plasma half-life and rapid degradation, accumulation is not a practical concern.

For dose ranges in published research, see the dosing reference page. For reconstitution guidance, see the reconstitution reference page.