Method validation studies and an inter-laboratory cross validation study of lenvatinib assay in human plasma using LC-MS/MS.

Cross validation studies for bioanalytical methods are important to ensure that assay data from all study sites where sample analysis is performed can be compared throughout clinical trials. To support global clinical studies of lenvatinib, a novel multi-targeted tyrosine kinase inhibitor, seven bioanalytical methods by liquid chromatography with tandem mass spectrometry (LC-MS/MS) were developed at five laboratories. In this study, methods were initially validated at each laboratory according to bioanalytical guidelines. For subsequent inter-laboratory cross validation, quality control (QC) samples and clinical study samples with blinded lenvatinib concentrations were assayed to confirm comparable assay data. Lenvatinib and an internal standard were extracted by protein precipitation, liquid-liquid extraction, or solid phase extraction and then detected in positive ion electrospray mode by multiple reaction monitoring using LC-MS/MS. The assay method developed at each laboratory was successfully validated with parameters within the acceptance criteria recommended by the guidelines. In the cross validation study, accuracy of QC samples was within± 15.3% and percentage bias for clinical study samples was within± 11.6%. These findings suggest that lenvatinib concentrations in human plasma can be compared across laboratories and clinical studies.