Effects of rituximab dose on hepatitis B reactivation in patients with resolved infection undergoing immunologic incompatible kidney transplantation.

Sensitized patients received desensitization therapy with rituximab for kidney transplantation. However, the impact of rituximab dose on hepatitis B virus (HBV) reactivation is unknown. Patients who underwent living donor kidney transplantation between 2008 and 2016 were grouped according to rituximab dose (control vs. standard-dose rituximab [375 mg/m] vs. reduced-dose rituximab [200 mg/body]) for comparison of HBV reactivation. A total of 336 hepatitis B surface antigen (HBsAg)-negative/antibody to hepatitis B core antigen (anti-HBc)-positive patients underwent kidney transplantation, of whom 91 (27.1%) received rituximab for desensitization (57 standard-dose and 34 reduced-dose rituximab). During the study period, eight patients experienced HBV reactivation (three in the control group, five in the standard-dose group). In the standard-dose group, four patients experienced hepatitis flare, and one patient died due to hepatic failure. No HBV reactivation occurred in the reduced-dose group. Standard-dose rituximab significantly decreased hepatitis B surface antigen antibody titer (anti-HBs; -99.8 IU/L) at 12 months, compared with reduced-dose rituximab (-20.1 IU/L) and control (-39.1 IU/L, P = 0.017). Standard-dose rituximab (HR, 10.60; 95% CI, 2.52-44.60; P = 0.001) and anti-HBs < 100 IU/L at transplantation (HR, 9.06; 95% CI, 1.11-74.30; P = 0.04) were independent risk factors for HBV reactivation. Standard-dose rituximab significantly increased HBV reactivation risk for HBsAg-negative/anti-HBc-positive kidney transplant patients.