Biogen Idec and Fumapharm AG announced positive results from a phase II study designed to evaluate the efficacy and safety of BG-12, an oral fumarate, in patients with relapsing-remitting multiple sclerosis (MS).

The study achieved its primary endpoint, demonstrating that treatment with BG-12 led to a statistically significant reduction in the total number of gadolinium-enhancing brain lesions as measured by MRI with six months of treatment versus placebo. These data were presented at the annual meeting of the European Neurological Society in Lausanne, Switzerland.

"We are encouraged that these phase II data demonstrate that BG-12 may be a promising oral therapy to treat MS. As part of our ongoing commitment to MS patients, we are working with regulatory authorities to determine the next steps in the development of this program," said Burt Adelman, MD, executive vice president, Development, Biogen Idec.

This phase II multi-centre, double-blind, placebo-controlled, dose-ranging study enrolled 257 patients at sites in 10 countries in Europe. Patients were randomized to receive placebo or BG-12 at 120 mg, 360 mg, or 720 mg per day for six months. The patient group treated with 720 mg of BG-12 per day had a 69 per cent reduction in the mean number of gadolinium-enhancing lesions versus placebo as measured monthly from weeks 12 to 24 of the study. The 720 mg dose group also had a 48 per cent reduction in newly enlarging T2-hyperintense lesions. BG-12 therapy was also associated with a trend towards reduction in relapse rate. The patient group treated with 720 mg of BG-12 per day had a 32 per cent reduction in relapse rate compared to placebo, however, the study was not designed to achieve statistical significance for this endpoint.

The results of the 120 mg and 360 mg BG-12-treated groups were not statistically significant versus placebo. Patients were followed for an additional six months as part of a dose-blinded safety extension study.

The most common adverse events were flushing, gastrointestinal disorders, headache, and nasopharyngitis. The incidence of liver enzyme elevation greater than or equal to three times the upper limit of normal at any time during the placebo controlled phase of the study was between 2 per cent and 8 per cent in the three active treatment groups, compared with 5 per cent in the placebo group. Improvement in liver enzyme levels was seen after discontinuation of BG-12. Infection rates were found to be balanced between the BG-12-and placebo-treated groups and no opportunistic infections occurred.