A Low Fixed Tacrolimus Starting Dose Is Effective and Safe in Chinese Renal Transplantation Recipients

BACKGROUND: We investigated whether a low fixed Tac starting dose regimen could lead to a better achievement of Tac target concentrations, as well as an effective immunosuppressive treatment, in Chinese kidney transplant recipients (KTRs). MATERIAL/METHODS: We collected whole-blood and serum samples from 189 KTRs and the Tac starting dose was 2, 2.5, or 3 mg/day. Information on Tac C(0), dose, body weight, body mass index (BMI), Scr, eGFR, and CYP3A5 genotypes were collected from a routine therapeutic drug monitoring database. The correlation between Tac C(0) and body weight (or BMI) was investigated by calculating the goodness of fit. Multivariable logistic regression was performed to estimate the independent associated factors. RESULTS: The patients with 3 mg per day of Tac had higher C(0) at day 7 compared to those with 2 or 2.5 mg. For patients receiving the same Tac starting dose, no significant difference was found in Tac C(0) at day 7 among different body weight or BMI groups. There was no significant difference in Scr or eGFR at 1 year after transplant, nor was there a significant difference in the rates of DGF or AR at post-transplant day 30 among different Tac starting dose groups or among the 3 Tac C(0) range groups. CYP3A5 genotype and Tac initial dose were independently associated with Tac C(0). CONCLUSIONS: CYP3A5 genotype and Tac initial dose were independently associated with Tac C(0) in renal transplant recipients. Our results suggest that a low Tac target C(0) range (5–8 ng/ml) with a low fixed starting dose (3 mg/day) would be safe and effective among Chinese KTRs.