Development and validation of the quantitative determination of avapritinib in rat plasma by a bioanalytical method of UPLC-MS/MS

Avapritinib, an orally consumed, highly selective inhibitor of platelet-derived growth factor receptor alpha (PDGFRA), is approved in the USA for PDGFRA exon 18 (including D842V) mutant gastrointestinal stromal tumour (GIST). The research conducted investigates an advanced reliable and fast UPLC-MS/MS method that could verify and determine avapritinib concentration in plasma of rats. An addition of acetonitrile was incorporated along with the plasma sample in order to precipitate protein with the analyte separated from the matrix by a gradient elution procedure on a Waters Acquity UPLC BEH C18 column (2.1 mm x 50 mm, 1.7 lm). The active stage in mobile phase consists of a mixture of 0.1% formic acid in water and acetonitrile with a 0.40 mL/min flow rate. UPLC-MS/MS detection was done employing a mode of multiple reaction monitoring (MRM), and the ion transitions of avapritinib and imatinib (internal standard, IS) was m/z 499.10-> 482.09, and m/z 494.30-> 394.20, respectively. This method has good linearity within 2-4000 ng/mL of avapritinib calibration range and a lower limit of quantification (LLOQ) of 2 ng/mL verified. Avapritinib precisions in both intra-day and inter-day were below 15% with the determined accuracy of-12.9% to 12.0%. The recoveries, stabilities, and matrix effect of avapritinib and IS were credible. 30 mg/kg avapritinib was administered as a single dose orally to rats. The determination of avapritinib level in pharmacokinetic studies was accomplished by effi-ciently applying a newly optimized UPLC-MS/MS assay. (c) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

An advanced UPLC-MS/MS method was developed to determine avapritinib concentration in rat plasma, demonstrating good linearity and a lower limit of quantification suitable for pharmacokinetic studies. The method involved the addition of acetonitrile and a gradient elution procedure, with reliable precision and accuracy for avapritinib analysis.