The US Food and Drug Administration has added a black box warning that ofatumumab (Arzerra) and rituximab (Rituxan) may reactivate hepatitis B virus (HBV).
Rituximab is used to treat rheumatoid arthritis and granulomatosis with polyangiitis, and both drugs are used for leukemia and lymphoma.
Patients should be screened for HBV with hepatitis B surface antigen and hepatitis B core antibody, says the notice.
If the result is positive:
1. Consult a hepatitis expert.
2. Monitor patients using these drugs for HBV.
3. If reactivated, stop and treat for HBV