FDA approves new drug for treating MS

The drug for multiple sclerosis uses a humanized monoclonal antibody to prevent immune cells from reaching the brain and spinal cord.

By Susan J. Landers, AMNews staff. Dec. 20, 2004.

Washington -- The Food and Drug Administration has licensed a new medication to treat the flare-ups of multiple sclerosis that occur in the majority of the 400,000 patients diagnosed with this chronic disease of the brain and spinal cord.

The drug, natalizumab, which will be marketed as Tysabri, was granted accelerated approval based on promising first-year results from a two-year trial now concluded. Its data are being analyzed.

But until the final results are in, physicians who specialize in treating patients with multiple sclerosis are eyeing the new offering with cautious optimism.

"I'm excited about what I consider to be this preliminary data," said Jack Burks, MD, a Reno, Nev., neurologist who specializes in treating patients with multiple sclerosis. "But I am waiting until the first quarter of next year when I can get the two-year data to see if my excitement is sustained or not. We've had the experience with drugs that have better one-year data than two-year data."

However, his patients are already clamoring for Tysabri, which many think may represent a cure.

"I would not take anyone who is doing well off their medication. If it ain't broke we don't need to fix it," said Dr. Burks, who is also the vice president and chief medical officer of the Multiple Sclerosis Assn. of America.

"The clinical trial results indicate that the drug is very effective in relapsing forms of MS and appears to be well-tolerated," said Aaron Miller, MD, chief medical officer of the National Multiple Sclerosis Society. The relapsing-remitting form of MS is the most common form of the disease and is characterized by symptoms that become dramatically worse before subsiding totally or partially.