GAITHERSBURG, Md. _ A drug that appears to stave off relapsesof the devastating nerve disease multiple sclerosis (MS) cleared animportant hurdle Thursday, when an FDA advisory panelrecommended that the drug, trade-named Copaxone, be approved formarketing.
The FDA's Peripheral and Central Nervous System Drugs advisoryCommittee unanimously agreed that the drug's developer, TevaPharmaceuticals Ltd., of Jerusalem, had demonstrated that Copaxoneeffectively controls the terrifying episodes of pain and paralysisregularly endured by the nation's 300,000 MS sufferers.
The committee also concurred, with one abstention, that Teva hadproved its product safe enough for widespread use.
News of the recommendation sent Teva's stock (NASDAQ:TEVIY)up $3.50, to close at $47 a share.
Sid Gilman, professor of neurology at the University of MichiganMedical Center and the committee's chairman, said the panel basedits approval on "two well controlled, double-blind studies indicatingthat the drug reduces the rate of relapses" in MS patients. The twotrials involved a total of 300 patients at 12 research centersnationwide.
Carole Ben-Maimon, senior vice president of Teva Pharmaceuticalswho brought the firm's case before the committee, said she waselated by the committee's decision. "Obviously, we're happy forpatients as well as for ourselves," she told BioWorld Today.
If the FDA follows the committee's recommendation, as it typicallydoes, Copaxone would become the third drug approved in three yearsfor the treatment of patients with chronic, relapsing MS. The othertwo drugs, Avonex, made by Biogen Inc. of Cambridge, Mass., andBetaseron, made by Chiron Corp., of Emeryville, Calif., are versionsof interferon.
The flurry of new medications offer renewed hope to hundreds ofthousands of people worldwide who are ravaged by the nerve-destroying disease. Although no one knows what causes multiplesclerosis, research has shown that the disease results when stimulatedT-cells begin attacking the whitish myelin sheath that insulates nervecells, causing the cells to short-circuit or misfire.
Copaxone, developed two decades ago by Michael Sela, Ruth Arnonand Dvora Teitelbaum, of the Weizmann Institute of Science, inRehovot, Israel, is made up of synthetic polypeptides composed offour amino acids. Although no one is sure precisely how the drugworks, researchers believe it suppresses the immune system'sdegenerative onslaught on the myelin sheath.
All three drugs appear to reduce by about one-third the rate ofrelapses suffered by people with MS. Avonex and Betaseron havebeen shown to slow the descent into paralysis and reduce the numberof nerve-cell lesions. Copaxone _ which patients inject into theirthighs or abdomen _ appears to slow the progression of the disease,and improve neurologic function in patients not yet disabled by nervedamage.
Copaxone, however, does not cause the flu-like side effects, anemiaand depression that have been variously reported with the two otherdrugs. The most common Copaxone side effect reported so far is amild weal and flare reaction at the injection site.
About 15 percent of patients also report brief symptoms of whatappears to be coronary distress usually lasting fewer than 30 minutes.The symptoms, chest tightness or pain; palpitations and flushing,appear to fade completely without causing any lingering illness.Indeed they disappear so quickly that no researcher has succeeded inclapping EKG electrodes on a patient's chest during such a flare-up.As a result, the cause of the symptoms remain a mystery.
Although several committee members expressed concern about thisunusual reaction, five voted that the drug was safe enough to bemarketed for the treatment of MS. Biostatistician Chris Gennings, ofthe Medical College of Virginia in Richmond, however, abstainedfrom voting on the question of safety because she harbored concernsabout the significance of these peculiar side effects _ and what mighthappen when the drug is approved for long-term use in tens ofthousands of sufferers.
David Drachman, a professor of neurology at the University ofMassachusetts Medical School and committee member, said, "We'realways hoping we'll see a drug that is as good as penicillin was forpneumonia. We're almost always disappointed when it turns out to bea drug with a small effect that isn't curative.
"Part of the problem with the drug," he said, "is nobody knows whatit is or what it does. It doesn't fit the simple model of a single drugwith a single activity that we understand."
Drachman noted, nonetheless, that the drug appears to be safe. "So itdoesn't violate our first principle of `do no harm.'"
Teva now provides the drug to about 600 patients nationwide under acompassionate use protocol approved by the FDA, which doubles asan open label trial. If the drug receives FDA approval, it will bemarketed in the U.S. by Teva Marion Partners. n
-- Steve Sternberg Special To BioWorld Today
(c) 1997 American Health Consultants. All rights reserved.