The Food and Drug Administration (FDA) announced new black box warnings for potentially fatal reactivation of hepatitis B viruses (HBV) were added to two drugs – one an immune suppressant and the other an anti-cancer medication. The warnings will be added to the labels of Arzerra (ofatumumab) and Rituxan (rituximab).
Arzerra 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 polyanglitis, and microscopic polyanglitis. Both drugs are in a class of medications known as CD20-directed cytolytic antibodies.
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 were later treated with Arzerra or Rituxan. Some cases have resulted in a type of liver failure known as fulminant hepatitis, hepatic failure and death.
Hepatitis B is irritation and swelling or inflammation of the liver due to infection with the hepatitis B virus. The new warning label on the drugs also includes additional recommendations for screening, monitoring, and managing patients with prior HBV on Arzerra or Rituxan to decrease the risk of HBV reactivation.