Management of patients with overt or resolved hepatitis B virus infection undergoing rituximab therapy

Introduction: Rituximab (RTX), a chimeric mouse anti-human CD20 monoclonal antibody, is indicated for the treatment of patients with non-Hodgkin's lymphoma, chronic lymphocytic leukemia, granulomatosis with polyangiitis and microscopic polyangiitis, and rheumatoid arthritis, but nowadays it is increasingly used for the treatment of many other immune-mediated disorders. Hepatitis B virus (HBV) reactivation in RTX-treated patients, eventually leading to fatal liver failure, has been reported more often among hepatitis B surface antigen (HBsAg)-positive patients (overt infection) than in HBsAg-negative, antibody to hepatitis B core antigen (anti-HBc) seropositive patients (resolved infection). Areas covered: This paper reviews the safety of RTX in patients with overt or resolved HBV infection, providing recommendations for its safe use in such patients. Expert opinion: Prior to starting RTX treatment, all patients should be screened for HBV infection. While HBsAg-positive active carriers should receive long-term antiviral treatment with entecavir (ETV) or tenofovir, inactive carriers are candidates for universal prophylaxis with lamivudine, or ETV or tenofovir in selected cases, to prevent hepatitis reactivation. Conversely, for HBsAg-negative anti-HBc positive carriers, that is, those with resolved HBV infection, universal prophylaxis with lamivudine is recommended for those with onco-hematological diseases, whereas watchful monitoring of HBsAg/HBV DNA levels is advisable for all the other indications.