New Multiple Sclerosis Drugs

With no drugs to offer a cure for multiple sclerosis (MS), clinicians should have a wide variety of treatment options available for their patients. The FDA has just approved the third oral disease-modifying medication available to treat patients with MS. Also, research on several promising MS drugs on the near horizon was presented at the recent American Academy of Neurology (AAN) annual meeting.

Dimethyl Fumarate
On March 27, the FDA approved dimethyl fumarate, to be sold under the name Tecfidera, to manage relapsing-remitting forms of MS. The drug, formerly known as BG-12, is manufactured by Biogen Idec. The other 2 MS drugs in the same category are fingolimod and teriflunomide.

Dimethyl fumarate has a mechanism of action that is novel compared with that of other MS drugs. It activates the nuclear factor–like 2 transcriptional pathway, which in turn reduces the oxidative stress that contributes to demyelination.

In 2 clinical trials, patients who received the drug had fewer MS relapses than those taking placebos. In 1 of the trials, those who received the drug experienced a worsening of disability less often than patients taking a placebo.

Adverse reactions reported in clinical trials include flushing, nausea, vomiting, and diarrhea. These adverse effects appear most often at the start of therapy and may decrease over time.

Alemtuzumab
At the AAN meeting, an interim analysis of 3-year data from an extension study using alemtuzumab showed strong long-term responses. In an update of 2 pivotal 2-year Phase 3 CARE-MS trials, rates of relapse and sustained accumulation of disability remained low and levels of disability remained stable or improved through 3 years. The extension study included patients from both CARE-MS I, which was conducted in treatment-naive patients, and CARE-MS II, which was conducted in patients who had relapsed on prior treatment.

Both studies randomized patients to alemtuzumab or interferon β-1a. Interferon patients were allowed to cross over to alemtuzumab at 1 year, and during the extension, patients were eligible to receive additional alemtuzumab treatment if they showed evidence of disease activity.

Efficacy was maintained through the first year of the extension study among the 349 enrolled patients, reported study coauthor Edward Fox, MD, of Central Texas Neurology Consultants in Round Rock, TX. Low annualized relapse rates were observed for alemtuzumab patients from both studies. More than half of the alemtuzumab patients from each study were still relapse-free, and more than 80% were free of sustained accumulation of disability. More than 70% of patients from each study had improved or stable disability. No new safety risks were identified.

Ocrelizumab
In an open-label extension study, patients who received the injectable biologic drug ocrelizumab and were followed for up to 72 weeks after the last dose experienced very little new MRI activity, low clinical disease activity, and no new safety concerns.

Stephen Hauser, MD, of the University of California San Francisco, reported 144-week results from a randomized phase II study in 218 patients with relapsing-remitting MS. The trial began with a 24-week phase in which patients were assigned to 1 of 2 ocrelizumab doses, placebo, or interferon β-1a.

Between weeks 96 and 144, 1 of 69 patients who received the higher drug dose experienced new gadolinium-enhancing MRI lesions. Two patients had new or newly enlarging lesions. No patients in the lower dose group had any newly active lesions, Dr Hauser reported.