PMID: 40276702 https://pubmed.ncbi.nlm.nih.gov/40276702/

Abstract

BACKGROUND: Hepatitis B virus reactivation (HBVr) can occur in patients with resolved hepatitis B virus (HBV) infection receiving immunosuppressive therapy. The class of immunosuppression influences HBV reactivation (HBVr) risk, with B-cell depleting agents such as Rituximab conferring a higher risk. The presence of hepatitis B surface antibodies (HBsAb) may be protective against HBVr.

OBJECTIVE: To compare the rates of HBVr amongst individuals with resolved HBV infection receiving rituximab and non-rituximab immunosuppressive therapy, without chemoprophylaxis. Our secondary objective was to explore the role of HBsAb in risk stratification for HBVr.

METHODS: We retrospectively collected the data of patients with resolved HBV infection receiving immunosuppressants between 2014 and 2022. HBVr rates amongst patients receiving rituximab and non-rituximab therapy were compared. Logistic regression analysis was performed to identify risk factors for HBVr.

RESULTS: 148 patients with resolved HBV infection did not receive chemoprophylaxis. Of the 20 (13.5%) patients who developed HBVr, none developed HBV flare. 42 of the 148 (28.3%) patients received rituximab-based therapy. Patients who received rituximab had a higher risk of HBVr, 12(28.6%) vs 8(7.5%),  = 0.001. This was confirmed on multivariable analysis (OR 4.19 [C.I. 1.47-11.9],  = 0.007). HBsAb titres of above 100 mIU/ml were protective against HBVr (OR 0.04 [CI 0.001-0.84],  = 0.039) in the rituximab exposed cohort, but not in the non-rituximab exposed cohort.

CONCLUSION: The risk of HBVr was higher in patients receiving rituximab; however, no patient developed HBV flare. In patients with resolved HBV infection, the presence of HBsAb titres above 100 mIU/ml may confer additional protection against HBVr and can be used as part of risk stratification for HBVr. In such patients, close surveillance with on-demand therapy instead of chemoprophylaxis may be considered.