LC-MS/MS determination of buparlisib, a phosphoinositide 3 kinase inhibitor in rat plasma: Application to a pharmacokinetic study.

Buparlisib is a selective phosphoinositide 3 kinase inhibitor currently evaluated in clinical trials. We developed and validated an LC-MS/MS coupled with a one-step protein precipitation extraction method for the quantitation of buparlisib in rat plasma. After protein precipitation with acetonitrile, the plasma sample was analyzed using a Cortecs UPLC C ₁₈ column, with acetonitrile-0.1% formic acid as the mobile phase system. Mass spectrometric detection was conducted in positive ionization mode, with target quantitative ion pair of m/z 411.2 → 367.2 for buparlisib. The calibration curve showed good linearity (1.0-3000 ng/ml), with acceptable accuracy (RE ranging from -6.2 to 5.9%) and precision (RSD within 8.2%) values at quality control concentrations. Extraction recovery from plasma was 80.9-88.7% and the matrix effect was negligible (92.6-95.2%). The validated method presented a simple quantification method of buparlisib in detail and utilized it for a pharmacokinetic study at three dose concentrations after oral administration in Wistar rats.
(© 2020 John Wiley & Sons, Ltd.)