Efalizumab: What Went Wrong?

Abstract

Efalizumab was approved for psoriasis in 2003. In 2008, two cases of progressive multifocal leukoenecephalopathy (PML) were reported, and in 2009, a third case was confirmed in patients on efalizumab monotherapy for psoriasis. As a result, in Europe, efalizumab's marketing authorization was suspended by the European Medicines Agency. Shortly thereafter, Genentech announced plans to withdraw the drug from the U.S. The withdrawal, which was completed in June 2009, was the result of the risk of an infection that is often fatal, with three confirmed PML cases out of the approximately 2,000 patients treated with efalizumab for more than three years. Efalizumab was one of the first biologics approved by the U.S. Food and Drug Administration for the treatment of moderate to severe plaque psoriasis. With the later approval of additional biologic agents for plaque psoriasis, prescribers had additional treatment options with improved efficacy and safety. The risks associated with efalizumab for its relatively low efficacy made it unattractive compared to other biologic product treatment options, ultimately leading to its withdrawal.