Pharmacokinetics of Afatinib after Intravenous and Oral Administrations in Rats Using Validated UPLC MS/MS Assay

Afatinib is designated as the first-line management therapy for patients with advanced non-small cell lung cancer, and metastatic head and neck cancer. LC coupled to MS/MS can be utilised in therapeutic drug monitoring to ensure optimal use of Afatinib with the reduction of its possible adverse reactions. The aim of this investigation was to determine the pharmacokinetics of Afatinib in rats after single IV (2 mg/kg) and oral (8 mg/kg) doses. Therefore, a selective, sensitive and precise UPLC MS/MS assay thru electrospray ionisation basis with positive ionisation approach was established to measure Afatinib concentrations in the rat. The precision and accuracy of the developed assay method in the concentration range of 10-1000 ng/ml show no significant difference among inter- and-intra-day analysis (P > 0.05). Linearity was detected over the studied range with correlation coefficient, r > 0.995 (n = 6/day). The pharmacokinetics of Afatinib in the rat after a single IV dose showed a mean terminal half-life of 4.6 ± 0.97 h, and a mean clearance 480 ± 80 ml/h/kg. After PO administration, a short absorption phase with a mean Tmax of 1.3 ± 0.6 h with the highest concentration of 513.9 ± 281.1 ng/ml, and the lowest concentration detected after 24 h was 18.8 ± 10.7 ng/ml.