Preclinical pharmacokinetics and disposition of a novel selective VEGFR inhibitor Fruquintinib (HMPL-013) and the prediction of its human pharmacokinetics

This study evaluated the preclinical pharmacokinetics (PK) and disposition of Fruquintinib (HMPL-013), a small molecule vascular endothelial growth factor receptors inhibitor.

In vitro and in vivo PK/ADME assays were conducted. Allometry and PK modeling/simulation were conducted to predict human PK parameters and the time course profiles.

HMPL-013 has high permeability without efflux. It shows moderate oral bioavailability of 42–53 % and T _max < 4 h in mouse, rat, dog and monkey, with exposure-dose linearity proved in rats and dogs. No significant food effect is on dog PK. HMPL-013 has moderately high tissue distribution. It majorly distributes in gastrointestinal tract, liver, kidney, adrenal and adipose. The plasma protein binding fraction is 88–95 % in mouse, rat, dog and human, invariable up to 10 µM. The in vivo clearance of HMPL-013 is low, consistent with the in vitro scaling. Three major oxidative metabolites were identified in liver microsomes of mouse, rat, dog, monkey and human. Dog is mostly similar to human regarding in vitro metabolism. Demethylation, hydroxylation and sequential glucuronidation are the major in vivo metabolic reactions. Direct urinary and biliary excretion of HMPL-013 is negligible. Metabolizing to M1 (demethylation), sequentially glucuronidating, followed by biliary excretion, and to a less extent, by urinary excretion, are important elimination pathways for HMPL-013 in rats. HMPL-013 has low risk of drug–drug interaction. It is predicted to have favorable human PK properties and low efficacious dose.

HMPL-013 demonstrates good preclinical PK and enables successful human PK and dose projection. It is valuable for further clinical development.