Currently,
crizotinib is the first generation drug, which has been used in the treatment of ALK-rearranged
non-small cell lung cancer (NSCLC). However, more and more patients are found in
crizotinib-resistance. In the last year,
alectinib has been approved for treatment of patients with
crizotinib-resistance. In this study, we aim to develop and validate a simple, rapid and sensitive tandem mass spectrometry (UHPLC-MS/MS) method for determination of
alectinib in rat plasma.
Diazepam was chosen as an internal standard (IS).
Protein precipitation by
acetonitrile was utilized to prepare plasma samples. Chromatographic separation was achieved on a RRHD Eclipse Plus C18 (2.1×50mm, 1.8μ) column with a gradient mobile phase consisting of
acetonitrile and water (containing 0.1%
formic acid). The analytes were detected by an electrospray ionization (ESI) source in positive mode. A dynamic multiple reaction monitoring (MRM) method was developed to detect specific precursor and product
ions. The target fragment
ions were m/z 483.2→396.1 for
alectinib and m/z 285.0→192.9 for
diazepam (IS). Linear calibration plots were achieved in the range of 1-500ng/ml for
alectinib (R2=0.997) in rat plasma. Mean recoveries of
alectinib in rat plasma ranged from 84.2% to 92.2%. The intra- and inter-day precision was below 9.3% and accuracy was from -1.4% to 12.1%. No obvious matrix effect was found. This method shows a good performance: accuracy, precision and stability. It has been fully validated and successfully applied to pharmacokinetic study of
alectinib.