Lack of association between ABCC2 polymorphisms and plasma carbamazepine concentrations or pharmacoresistance in Chinese patients with epilepsy.

Multidrug resistance proteins (MRP2, ABCC2) may play a role in drug resistance in epilepsy by limiting gastrointestinal absorption and brain access of antiepileptic drugs (AEDs). We sought to investigate the effects of ABCC2 polymorphisms on plasma carbamazepine (CBZ) concentrations and pharmacoresistance in Chinese patients with epilepsy. ABCC2 rs717620, rs2273697, rs3740066 polymorphisms were genotyped by polymerase chain reaction amplification followed by restriction fragment length polymorphism analysis or direct automated DNA sequencing in 80 patients treated with CBZ monotherapy. There were no differences in CBZ maintenance doses or adjusted plasma CBZ concentrations among the ABCC2 rs717620, rs2273697 and rs3740066 genotypic groups. No associations between all the studied genotypes and haplotypes involving the three SNPs of ABCC2 and CBZ resistance were observed in this patient cohort. These results suggest that ABCC2 polymorphisms may not contribute to interindividual variabilities in CBZ daily maintenance doses, plasma concentrations, and treatment efficacy. [ABSTRACT FROM AUTHOR]