October 23, 2008

Cancer Drug Shows Promise Against MS but With Some Risks

By Rita Rubin

A leukemia drug was about 70% more effective than a standard therapy in treating early multiple sclerosis, according to clinical trial results in today's New England Journal of Medicine.

In multiple sclerosis, or MS, the immune system attacks myelin, the sheath that enables nerve cells to conduct impulses between the brain and other parts of the body.

The drug, alemtuzumab, depletes the body of the white blood cells that attack myelin, which are eventually replaced by new white blood cells that don't. For reasons not yet clear, though, alemtuzumab raised patients' risk of autoimmune diseases of the thyroid or platelets, and one study participant died as a result.

Closer monitoring of patients in larger trials before the drug is approved for MS should head off such problems, says co-author Susan Moran, medical director at Genzyme, which co-funded the study with Bayer Schering Pharma.

In the MS trial, researchers randomly assigned 334 patients to get either alemtuzumab or Rebif, a brand of interferon beta, for three years.

Participants all had relapsing-remitting MS, the initial diagnosis for 85% of people with MS, characterized by attacks of worsening neurologic function followed by partial or complete remissions.

Although he calls the alemtuzumab trial's results "remarkable," Stephen Hauser, a University of California-San Francisco neurologist, writes in an editorial that alemtuzumab's "toxic effects ... considerably dampen any enthusiasm for its routine use ... until more is known about its long-term safety and sustained efficacy."

In an interview, John Richert, executive vice president for research and clinical programs at the National MS Society, notes that alemtuzumab "is many years away from being generally available as a treatment for MS."

A larger and longer trial is needed, Richert says, to see whether alemtuzumab "is as strongly efficacious" as the newly published results suggest. (c) Copyright 2008 USA TODAY, a division of Gannett Co. Inc. <>