Three patients using psoriasis drug developed deadly infection, FDA says

ROCKVILLE, Md. Three patients, and possibly one more, using a biotech drug for treating psoriasis developed a deadly viral infection of the brain, according to a Food and Drug Administration advisory.

The FDA said Thursday that three patients taking Genentech's drug Raptiva (efalizumab) for more than three years developed progressive multifocal leukoencephalopathy and died. One more may have developed the disease. None were receiving other treatments that suppress the immune system. 

In October, the labeling for Raptiva was revised to highlight in a boxed warning the risks of dangerous infections, including PML. The drug works by suppressing T-cells. 

PML results from an opportunistic infection by the JC virus, causing irreversible decline in brain function and death in people with severely weakened immune systems. According to the National Institutes of Health, most people carry the JC virus, though it is harmless to those with healthy immune systems. 

The agency is reviewing the reports and has said it will ensure that the risks of Raptiva do not outweigh its benefits, that patients receiving the drug are clearly informed of the signs and symptoms of PML and that healthcare professionals carefully monitor patients for possible development of the disease.