Risk of HBV reactivation persists in cancer patients receiving antivirals

Cancer patients administered with prophylactic antiviral drugs are still at risk of hepatitis B virus (HBV) reactivation during chemotherapy, a Taiwan study has found.

“HBV carriers who receive systemic cancer chemotherapy have been found to be at a higher risk of HBV reactivation,” the authors said. “However, lack of standard prophylaxis protocol resulted in life-threatening adverse events.”

This retrospective cohort study investigated the incidence of HBV infection, the prechemotherapy screening rate of hepatitis B surface antigen (HBsAg), and the severity of HBV reactivation of cancer patients receiving intravenous chemotherapy between 2013 and 2014. Patients on local chemotherapy with intracavity instillation, drug- or alcohol-related hepatitis, or chemotherapy for immune diseases were excluded.

Of the 784 patients analysed, 404 (51.53 percent) underwent HBsAg testing prior to chemotherapy, and 61 (7.78 percent) tested positive. Only 32 patients (4.08 percent) received prophylactic HBV antiviral therapy. Those who received antiviral drugs had significantly reduced risk of HBV reactivation compared with nonprophylaxis (relative risk, 0.53; number needed to treat, 12).

In addition, the analysis revealed specific single or combined chemotherapy that could cause HBV reactivation different from those of other studies conducted in Western countries. The differences may refer to enzymes, proteins, and immune response of patients.

“Our findings indicate that cancer patients receiving prophylactic antiviral drugs remain at risk of HBV reactivation during chemotherapy,” the authors said. “Therefore, the HBV screen and chemotherapy control system was established in 2017 to reduce the risk of HBV reactivation and improve patient safety.”