The product monograph change will help enable individual benefit risk assessment for MS patients.
The new label identifies anti-JCV antibody status as a risk factor for developing an uncommon, but serious, brain infection known as progressive multifocal leukoencephalopathy (PML).
Biogen Idec Canada general manager Paul Petrelli said Tysabri has benefited thousands of patients worldwide who are living with multiple sclerosis, an often devastating disease affecting people in the prime of their lives.
Infection with the JCV is necessary for the development of PML. The new label states that anti-JCV antibody negative status indicates that exposure to the JC virus has not been detected, while patients who are anti-JCV antibody positive have an increased risk of developing PML.