The hepatitis B warnings on two blood cancer drugs were recently strengthened by the Food and Drug Administration (FDA), according to Fox News. The strengthened warnings were issued to reflect the risk of reactivating the hepatitis B virus in patients previously infected with the disease who are taking the cancer drugs.
The warnings were strengthened for GlaxoSmithKline Plc’s Arzerra and Roche Holding AG and Biogen Idec Inc.’s Rituxan. Arzerra was approved in the United States in 2009 and is used to treat chronic lymphocytic leukemia (CLL). Rituxan was approved to treat CLL, non-Hodgkin’s Lymphoma and rheumatoid arthritis.
More patient deaths and reactivations of hepatitis B in patients have led to the need for the strengthened warnings even after the original warnings were placed. The strengthened warnings will now be black box warnings. This is the sternest warning given by the FDA to a medication while still remaining on the market in the U.S.
The FDA requires a black box warning for one of two reasons: either the drug may cause serious, life-threatening side effects, or serious adverse reactions can be prevented or reduced through proper use of the drug.
All physicians are recommended to screen patients for hepatitis B before prescribing Arzerra or Rituxan. Patients with prior history of hepatitis B should be monitored for signs that the virus has been reactivated. The FDA recommends physicians monitor patients for several months after therapy has stopped, as well.
Hepatitis B is a serious liver infection that can lead to life-threatening consequences, including liver failure, liver cancer or cirrhosis ( a permanent scarring of the liver). Because Arzerra and Rituxan work by suppressing the body’s immune system, which is essential in fighting off infections, patients with a history of hepatitis B are more susceptible to its reoccurrence.
Hepatitis B can be spread through contact with body fluids or blood, and it is best prevented through vaccination.