Description: The drug rituximab reduces disease activity in people with the relapsing-remitting form of multiple sclerosis (MS), according to two new studies.

Rituximab selectively targets and depletes a subset of immune cells called B-cells by targeting a specific protein on the cell surface. It's the first drug designed to target B-cells and may offer a new treatment for relapsing-remitting MS.

In one study, University of California, San Francisco, researchers gave two infusions of rituximab, delivered two weeks apart, to 69 patients, while 35 other patients received a placebo.

During the following six months, the patients who received rituximab had 90 percent fewer brain lesions and 58 percent fewer drug relapses than the patients who received the placebo (14.5 percent vs. 34.3 percent).

In the second study, researchers at McGill University in Montreal gave 26 patients two infusions of rituximab two weeks apart