Genentech Inc., unit of Roche Holding AG, said on April 8 to voluntarily withdraw its psoriasis drug Raptiva (efalizumab) from the market after it was linked with progressive multifocal leukoencephalopathy (PML), a rare but fatal brain disorder. The company said it made this decision together with the FDA, which approved Raptiva for patients with chronic moderate to severe plaque psoriasis in 2003. Since then about 46,000 patients worldwide have taken it. From now on no new prescriptions will be written and the drug will no longer be available after June 8.