Hepatitis B

FDA Warns of Hepatitis B Reactivation Risk with Immune-suppressing Cancer Drugs


The U.S. Food and Drug Administration (FDA) announced this week that it has approved labeling changes for 2 monoclonal antibody cancer drugs, ofatumumab (Arzerra) and rituximab (Rituxan), adding a stronger "black box" warning that they may cause hepatitis B virus (HBV) reactivation.

Many people with chronic hepatitis B are able to keep the virus in check under normal circumstances, but may experience reactivation -- or resumption of viral replication -- when their immune function is impaired.

The FDA advised clinicians to screen patients for HBV before prescribing ofatumumab or rituximab, and urged people with a history of hepatitis B to inform all their health care providers before taking these drugs.

Below is an edited excerpt from the FDA's recent safety advisory.

Arzerra (ofatumumab) and Rituxan (rituximab): Drug Safety Communication -- New Boxed Warning, Recommendations To Decrease Risk of Hepatitis B Reactivation

POSTED: 9/25/13

AUDIENCEOncology, Pharmacy, Rheumatology, Patient

ISSUEFDA approved changes to the prescribing information of the immune-suppressing and anti-cancer drugs Arzerra (ofatumumab) and Rituxan (rituximab) to add new Boxed Warning information about the risk of reactivation of hepatitis B virus (HBV) infection. The revised labels also will include additional recommendations for screening, monitoring, and managing patients on these drugs to decrease this risk.

In patients with prior HBV infection, HBV reactivation may occur when the body’s immune system is impaired. HBV reactivation has occurred in patients with prior HBV exposure who are later treated with drugs classified as CD20-directed cytolytic antibodies, including Arzerra (ofatumumab) and Rituxan (rituximab). Some cases have resulted in fulminant hepatitis, hepatic failure, and death.

See the FDA Drug Safety Communication for additional information, including a Data Summary.

BACKGROUNDArzerra is used to treat chronic lymphocytic leukemia (CLL) in patients who have further disease after treatment with the anti-cancer drugs fludarabine and alemtuzumab. Rituxan is used to treat non-Hodgkin’s lymphoma and CLL. It is also used to treat other medical conditions, including rheumatoid arthritis, granulomatosis with polyangiitis, and microscopic polyangiitis.

RECOMMENDATIONSTo decrease the risk of HBV reactivation, FDA recommends that health care professionals:

For Patients:

Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program:



Food and Drug Administration. Arzerra (ofatumumab) and Rituxan (rituximab): Drug Safety Communication -- New Boxed Warning, Recommendations to Decrease Risk of Hepatitis B Reactivation. Drug safety advisory. September 25, 2013.

Food and Drug Administration. FDA Drug Safety Communication: Boxed Warning and New Recommendations To Decrease Risk of Hepatitis B Reactivation with the Immune-suppressing and Anti-cancer Ddrugs Arzerra (ofatumumab) and Rituxan (rituximab). Safety announcement. September 25, 2013.