Plasma and cerebrospinal fluid pharmacokinetics of MP470 in non-human primates

MP470 is a multi-targeted tyrosine kinase inhibitor with potent activity against mutant c-Kit, PDGFR alpha, Flt3, c-Met and c-Ret that is being evaluated as an anticancer agent. The plasma and cerebrospinal fluid (CSF) pharmacokinetics of MP470 were studied in a non-human primate model that is highly predictive of CSF penetration in humans. Oral MP470, 300 mg, was administered to four non-human primates. Serial samples of blood were collected from four animals and CSF samples from three animals for pharmacokinetic studies. Plasma and CSF concentrations were measured using an LC-MS/MS assay. Both model-independent and model-dependent methods were used to analyze the pharmacokinetic data. Following a one-time oral dose of 300 mg, the MP470 plasma area under the curve (AUC) was 1,690 +/- A 821 nM h (mean +/- A SD). The half-life of MP470 in the plasma was 11.0 +/- A 3.4 h. There was no measurable MP470 in the CSF. Although CSF penetration is minimal, MP470 has demonstrated potent activity against cancer cell lines in vitro and in vivo, and further clinical investigation is warranted.