How is Raptiva Causing PML for some Raptiva Patients

Progressive multifocal leukoencephalopathy (PML) is a rapidly progressive, often fatal viral infection of the brain. PML is believed to be due to the Jacob-Creutzfeldt (JC) papovavirus or JC virus. The virus infects oligodendrocytes (support cells in the brain).

Symptoms of PML

The signs and symptoms of PML include headaches, memory loss, changes in mental status, speech and vision difficulties, loss of strength, limb weakness, seizures, partial paralysis, loss of coordination, clumsiness, memory loss, progressively worsening weakness of the legs, and to a lesser extent, arms. Other signs of PML may include loss of language capability (aphasia), visual field defects, and headaches. The greatest risk is being immunosuppressed. The causal virus, JC virus, is a common resident in most adults, but it triggers loss of myelin in those whose immune function is deficient. It occurs in 4% of adult individuals with AIDS.

Raptiva and PML

On April 8, 2009, the FDA announced that Genentech, the manufacturer of the psoriasis drug Raptiva (efalizumab), will begin a voluntary, phased withdrawal of Raptiva from the U.S. market. The company is taking this action because of a potential risk to patients of developing progressive multifocal leukoencephalopathy (PML).