FDA advisers urge approval of multiple sclerosis drug

Friday, January 28th 2000, 12:00 am

By: News On 6

WASHINGTON (AP) -- A cancer drug appears to ease advanced multiple sclerosis, government scientists decided Friday, leaving Novantrone in line to become the nation's first treatment for tens of thousands of Americans with crippling late-stage MS.

But Novantrone can be used only for about two years before it suddenly and mysteriously increases patients' risk of dangerous heart damage, and MS is a disease patients battle for decades.

So using Novantrone safely, quitting the drug around that two-year mark, will require intense patient and doctor education,
members of a Food and Drug Administration advisory committee warned.

The FDA is not bound by its advisers' recommendations but usually follows them. If approved, Novantrone would become the
first official treatment for "secondary progressive MS," the most severe form of the debilitating neurologic disease.

About 350,000 Americans have MS, which starts with such symptoms as numbness, tingling and fatigue but progresses to difficulty
walking and seeing and eventually paralysis. It usually strikes people ages 20 to 40.

MS tends to come in sporadic attacks, or flares. Some patients have "relapsing-remitting MS," periods of severe symptoms after which patients almost totally recover until the next attack. But 40 percent of MS patients have the worse "secondary progressive" form, where the flares become more and more frequent, and they don't recover from the damage each one causes.

Three drugs are in use that can somewhat ease relapsing-remitting MS, but until now no drug has been proved to work against the more severe form, said Dr. Craig Smith of
Seattle's Swedish Medical Center.

MS occurs when patients' immune systems go awry and attack the fatty layer of insulation, called myelin, that protects nerve fibers in the brain and spine, thus damaging or even destroying nerves.

Novantrone, a cancer drug made by Seattle-based Immunex Corp., works against MS by suppressing those attacking immune cells.

In a two-year study of 194 Europeans with advanced MS, high doses of the drug slowed the disease's progression by 65 percent.

Novantrone causes side effects typical of cancer chemotherapy; some nausea, hair loss, menstrual disorders, certain infections.

But the main worry is that after patients take a certain amount of the drug, the amount most would get over a two-year period, they become at risk for heart failure. Doctors don't really understand why.

"If this drug is approved, it's only going to be a short-term drug and there will be risks associated with it," cautioned Dr. Stephen Reingold of the National Multiple Sclerosis Society.

It may prove difficult to get MS patients who feel healthy when taking Novantrone to give it up for fear of the heart problem. Thus FDA's advisers urged the agency to make the danger very clear, and consider ways for doctors to measure accurately when MS patient are
becoming at risk so they stop the drug.

Novantrone currently is sold to treat certain leukemia and prostate cancer patients. That means regardless of whether FDA formally approves it for MS, doctors today can legally prescribe the drug to MS patients. Some are doing so.

"Frankly, I don't have anything else to use," said Smith, who began prescribing Novantrone after learning of the European study.

Smith's patient, Catherine Sykes, has been on Novantrone for a year, after older MS drugs did nothing to stop the flares that struck every few months.

"I have not had one exacerbation since I've been on the chemotherapy," she said, and her only side effect is a little nausea. "I've noticed improvements in my walking. I have less
fatigue and better muscle control."

Novantrone is given intravenously once every three months, costing $2,800 to $3,000 for a year's treatment.