Optimization of a sensitive and reliable UPLC-MS/MS method to simultaneously quantify almonertinib and HAS-719 and its application to study the interaction with nicardipine.

Context: Almonertinib is primarily metabolized by CYP3A4, so it could interact with a variety of drugs metabolized by CYP3A4, leading to the changes of systemic exposure.

Objective: For the purpose of this experiment, an ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay with accuracy and simplicity was optimized and fully validated for the simultaneous quantitative determination of almonertinib and its metabolite HAS-719, and drug-drug interactions (DDI) between almonertinib and nicardipine and was researched.

Materials And Methods: Detection of analytes was achieved by UPLC-MS/MS coupled with multiple reaction monitoring (MRM) in the positive ion mode with ion transitions of 526.01 → 72.04 for almonertinib, 512.18 → 455.08 for HAS-719 and 447.16 → 128.11 for IS, respectively.

Results: There was favourable linearity in the 0.5-200 ng/mL calibration range for almonertinib and 0.5-100 ng/mL for HAS-719. The lower limit of quantification (LLOQ) for both analytes was 0.5 ng/mL. The precision, accuracy, stability, matrix effect and extraction recovery required for methodological validation were consistent with the requirements of FDA guideline. Then, the UPLC-MS/MS assay was employed successfully on the interactions of almonertinib and nicardipine and . The half-maximal inhibitory concentration (IC) was 1.19 μM in rat liver microsomes (RLM), where nicardipine inhibited the metabolism of almonertinib with a mixed inhibitory mechanism. In pharmacokinetic experiments of rats, it was observed that nicardipine could significantly alter the pharmacokinetic profiles of almonertinib, including AUC AUC and C, but had no effect on the metabolism of HAS-719.

Conclusion: According to the findings, it was indicated that nicardipine could inhibit the metabolism of almonertinib .