The effect of CYP3A5 6986A>G and ABCB1 3435C>T on tacrolimus dose-adjusted trough levels and acute rejection rates in renal transplant patients

In the present study, we performed a systematic review and meta-analysis on published data to examine the impact of CYP3A5 6986A>G and ABCB1 3435C>T polymorphisms on tacrolimus dose-adjusted trough levels (C0/D) and acute rejection rates in adult renal transplant patients. Despite the presence of significant heterogeneity in all comparisons, random-effects model showed significantly higher tacrolimus C0/D in CYP3A53/3 compared with CYP3A51 allele carriers, either in the overall analysis and when stratifying for ethnicity or time of post-transplantation (≤1, 3-6, 12-24 months). In contrast, no consistent evidence of an effect of the ABCB1 3435C>T variant was detected on tacrolimus C0/D, except for a modest effect limited to the first month after renal transplantation. In addition, from the current evidence available, CYP3A5 6986A>G and ABCB1 3435C>T polymorphisms seem to have little or no effect on the acute rejection rates in renal transplant patients under immunosuppressive therapy with tacrolimus.