A case of progressive multifocal leukoencephalopathy (PML) has been reported in a rheumatoid arthritis patient taking rituximab (Rituxan) who had not previously received anti-tumor necrosis factor therapy, according to the FDA and the drug's manufacturer.
The case is the third seen with rituximab in rheumatoid arthritis, according to a "Dear Healthcare Professional" letter issued by Genentech. The previous two were seen in patients who had received anti-TNF drugs earlier.
PML causes inflammation in the brain, which has been fatal in about half of patients. It is caused by reactivation of latent JC virus infection, presumably a result of immune suppression.
Other biologic drugs targeting immune system components have been linked to PML, as well, including natalizumab (Tysabri) and efalizumab (Raptiva).
Both those drugs were removed from the U.S. market after cases of PML appeared, although natalizumab was later reintroduced with a strict risk evaluation and mitigation strategy. (See Raptiva Yanked from U.S. Market and Tysabri (natalizumab) Allowed Back to Market with Restrictions)
"Physicians should consider PML in any patient being treated with Rituxan who presents with new onset neurologic manifestations," Genentech's letter said. "Consultation with a neurologist, brain MRI, and lumbar puncture should be considered as clinically indicated."
The most recent case involved a 73-year-old woman who had received two doses of rituximab in February 2009. Symptoms developed four to six months later, Genentech said.
The woman had also taken leflunomide, hydroxychloroquine, and prednisone -- but not anti-TNF drugs such as infliximab (Remicade) or Etanercept (Enbrel).
http://www.medpagetoday.com/Rheumatology/Arthritis/16607bump interesting....I wonder if the PML shows up quickly or can show up anytime...