Association of ABCB1 Polymorphisms with Erlotinib Pharmacokinetics and Toxicity in Japanese Patients with Non-Small-Cell Lung Cancer

AIMS: We analyzed the association of ABCB1 polymorphisms with erlotinib-induced toxicity and the pharmacokinetics in patients with non-small-cell lung cancer. MATERIALS & METHODS: After erlotinib 150 mg was administered to 50 patients, ABCB1 polymorphisms were analyzed via either TaqMan(®) assays or direct nucleotide sequencing. Plasma concentrations were measured by HPLC. RESULTS: The trough concentration at steady state in patients with the ABCB1 1236TT-2677TT-3435TT genotype was higher compared with others groups (p = 0.021) and patients carrying this genotype had a higher risk of developing higher grade 2 toxicity (p = 0.012). CONCLUSION: The present study suggested that the ABCB1 1236TT-2677TT-3435TT genotype was associated with higher plasma concentration and the risk of developing higher toxicity in patients treated with erlotinib.