Background: Nucleoside drug transporter polymorphisms play a significant role in patient responses to drugs. The aim was to investigate the effect of multi-drug resistance protein 4, multi-drug resistance protein 5 and human concentrative nucleoside transporter 1 gene polymorphisms on the response to entecavir treatment in chronic hepatitis B patients.
Methods: A total of 324 chronic HBV treatment-naive Chinese Han patients treated with entecavir 0.5 mg daily for 1 year were enrolled. Patients were divided into a response group and non-response group according to the decline of HBV DNA levels. A multiplex SNaPshot single-base extension method was designed for genotyping.
Results: The rs3751333GG genotype of multi-drug resistance protein 4 was significantly different between the response group and non-response group at 6 and 12 months (P=0.005 and P=0.019, respectively). Multivariate analysis showed that the rs37751333GG genotype was significantly associated with responses at 6 and 12 months (odds ratio 2.630, 95% CI 1.391, 4.974, P=0.003; odds ratio 2.968, 95% CI 1.416, 6.221, P=0.004).
Conclusions: The multi-drug resistance protein 4 variant was significantly associated with HBV DNA level suppression in chronic hepatitis B patients treated with entecavir, and therefore, patients with the rs3751333GG genotype might respond better to entecavir in the Chinese Han population.