Development and validation of a UPLC-MS/MS method for almonertinib with its active metabolite HAS-719 and anlotinib in human plasma

Almonertinib and anlotinib are tyrosine kinase inhibitors used to treat malignant tumors, with their combination currently applied to non-small cell lung cancer (NSCLC) patients. This study aimed to develop a simple and rapid UPLC–MS/MS method for simultaneously detecting almonertinib, its active metabolite HAS-719, and anlotinib in human plasma. The analytes were separated on a Waters HSST3-C18 column following protein precipitation with acetonitrile. Mass detection was performed on a Waters TQS triple quadrupole mass spectrometer under positive electrospray ionization mode. The MRM ions were m/z 526.5→71.96 for almonertinib, m/z 512.4 → 455.41 for HAS-719, m/z 408.16→ 339.03 for anlotinib and m/z 518.5→372.26 for d6-HAS-000719 (internal standard). Method validation followed FDA guidelines and Chinese Pharmacopoeia regulations, demonstrating acceptable accuracy, precision, matrix effects, recovery, and stability. The method showed excellent linearity over 0.5–500 ng/mL for all three analytes, with correlation coefficients (r²)≥ 0.99. The validated UPLC-MS/MS method successfully monitored almonertinib and anlotinib concentrations in clinical, particularly for NSCLC patients.