A sensitive HPLC-FLD method for the quantification of alpelisib, a novel phosphatidylinositol 3-kinase inhibitor, in rat plasma: Drug metabolism and pharmacokinetic evaluation in vitro and in vivo

•A new bioanalytical HPLC-FLD method to determine alpelisib.•Alpelisib was unstable under acidic conditions including SGF.•Nonlinear PK of IV alpelisib owing to saturation of systemic metabolism process.•Alpelisib metabolism occurs ubiquitously among various tissues in the body.•Nonlinear PK of oral alpelisib owing to saturation of GI absorption process.