BG-12 (dimethyl fumarate) significantly reduced the annualized relapse rate among patients with multiple sclerosis (MS) compared with placebo, according to two studies published in the September 20 New England Journal of Medicine.
In one study, Robert J. Fox, MD, a staff neurologist and Medical Director at the Mellen Center for Multiple Sclerosis at the Cleveland Clinic, and colleagues enrolled 1,417 patients in a multicenter, double-blind phase III trial of BG-12. Approximately equal groups of patients were randomized to 240 mg of BG-12 twice daily, 240 mg of BG-12 three times daily, 20 mg of glatiramer acetate, or placebo. The researchers performed standardized neurologic assessments every 12 weeks.
After two years, twice-daily BG-12 reduced the annualized relapse rate to 0.22. BG-12 thrice daily reduced the annualized relapse rate to 0.20. Compared with placebo, the drug significantly reduced the numbers of new or enlarging T2-weighted hyperintense lesions and new T1-weighted hypointense lesions.
In the second study, Ralf Gold, MD, Director of Neurology at St. Josef-Hospital in Bochum, Germany, and colleagues conducted a double-blind, phase III trial that included 952 patients with relapsing-remitting MS. Equal groups of patients were randomized to 240 mg of BG-12 twice daily, 240 mg of BG-12 thrice daily, or placebo. The researchers performed standardized neurologic assessments every 12 weeks.
Dr. Gold's group found that 27% of patients taking BG-12 twice daily had had a relapse at two years, compared with 26% of patients taking BG-12 thrice daily and 46% of patients taking placebo. The annualized relapse rate at two years was 0.17 for patients taking twice-daily BG-12 and 0.19 for patients taking thrice-daily BG-12. In contrast, control patients had a relapse rate of 0.36.
"The average age at onset of MS is in the late 20s, and it typically results in disability only after 15 to 20 years," said Allan H. Ropper, MD, Executive Vice Chair of Neurology at Brigham and Women's Hospital in Boston, in an accompanying editorial. "Even fumarate will need to prove that its efficacy is durable by reducing disability over the many decades that encompass the representative course of multiple sclerosis," he added.