Hepatitis B Virus Reactivation Potentiated by Biologics.

Hepatitis B virus (HBV) reactivation can be a serious complication for patients with chronic or resolved HBV infection when treated with biologics. For HBsAg-positive patients receiving biologics, the risk of HBV reactivation is moderate to high. HBsAg-negative/anti-HBc positive patients are at lower risk of HBV reactivation than HBsAg-positive patients. However, patients taking anti-CD20 agents, such as rituximab, have high risk of HBV reactivation (>10%), so antiviral prophylactic therapies are required. This review provides the different classes of biologics associated with HBV reactivation, stratifies the various reactivation risk levels by HBV status and biologic agent, and discusses management strategies.