BETHESDA, MD 28 March 2013—Biogen Idec on February 27 announced the approval of dimethyl fumarate delayed-release oral capsules for the treatment of relapsing forms of multiple sclerosis.
The drug will be available within the coming days under the brand name Tecfidera, according to the company.
The labeling (PDF) for dimethyl fumarate states that after ingestion, the drug is rapidly converted to its active metabolite, monomethyl fumarate. The drug's mechanism of action is unknown but may be related to the activation of a pathway involved in cells' response to oxidative stress.
In two placebo-controlled clinical trials involving patients with relapsing forms of multiple sclerosis, those treated with dimethyl fumarate had less disease activity, with fewer relapses, fewer or less severe neurologic lesions, and, in one study, less disease progression.
The most frequently reported adverse events associated with dimethyl fumarate use were flushing, which affected about 40% of clinical trial participants, and gastrointestinal symptoms, according to the drug's labeling. Administration of the drug with food may reduce flushing, the labeling states.
According to the labeling, lymphocyte levels fell by about 30% during the first year of dimethyl fumarate use by clinical trial participants with multiple sclerosis and then remained stable. Four months after discontinuing treatment, the patients' lymphocyte levels had increased but remained below the baseline values.
The labeling recommends that clinicians, before prescribing dimethyl fumarate, use the results of a recent complete blood count to identify patients who already have a low lymphocyte count. During therapy, clinicians should obtain a complete blood count annually or as clinically indicated.
If the patient has a serious infection, consideration should be given to withholding dimethyl fumarate treatment until the infection resolves, the labeling states.
The recommended starting dosage of dimethyl fumarate is 120 mg taken twice daily with or without food. After seven days, the dosage should be increased to 240 mg twice daily. The hard gelatin capsules must be swallowed whole and must not be chewed, crushed, or opened and sprinkled over food.
Dimethyl fumarate will be available as 120-mg capsules in bottles of 14 each and 240-mg capsules in bottles of 60 each. A 30-day starter pack with bottles containing 14 120-mg capsules and 46 240-mg capsules will also be available.
The labeling states that the capsules are to be stored in their original container and discarded 90 days after the bottle is first opened.