Panel recommends return of MS drug

A multiple sclerosis drug recalled by its manufacturers last year because of safety concerns could be back on the market as early as April.

A committee of scientists unanimously recommended on Wednesday that the drug Tysabri once again be made available to multiple sclerosis patients despite its links to a life-threatening side-effect.

A final decision by the U.S. Food and Drug Administration is expected by March 26. Only one other drug, Lotronex for irritable bowl syndrome, has been returned to the U.S. market after being pulled because of safety concerns.

The February 2005 withdrawal of Tysabri, manufactured by Biogen Idec of Boston and Elan Corp. of the Republic of Ireland, came as a blow to MS patients, including many in the Inland Northwest, where incidence of the incurable disease appears to be high. MS is a brain disease that can lead to muscle weakness, difficulty concentrating, slurred speech and paralysis.

Dr. Roy Kanter, medical director of Holy Family Hospital’s MS Center in Spokane, said patients ask him every day about Tysabri, which has proven effective in slowing the progression of the disease and decreasing the number of relapses in patients.

“This is a drug that can really help a lot of people,” Kanter said.

But he cautioned that Tysabri, if it is approved for use, will only be made available to a limited number of patients, and then only under close surveillance.

That is because the drug, which showed so much promise when it was introduced last year, was linked to a potentially fatal infection called progressive multifocal leukoencephalopathy that developed in three people, two of whom died.

Three months after FDA approval, Tysabri’s manufacturers voluntarily recalled the drug pending further study.

At least two of the patients who developed PML were taking Tysabri in combination with another MS drug, Avonex, and Kanter said it has not been determined whether Tysabri alone can cause PML, which only occurs in immuno-suppressed patients.

MS is an autoimmune disease, and Tysabri works by suppressing a particular immune mechanism called integrins, which are instrumental in getting white blood cells into the central nervous system, Kanter explained. It could be that these same white blood cells in the central nervous system are what prevent PML.

“Usually people who develop PML also develop other types of infections.” Kanter said. That was not seen with Tysabri.

On Tuesday, the committee heard from several people with MS who spoke in favor of the drug. Many of them have found relief only in Tysabri.

“Most people in (Tysabri) studies did not have a relapse and did not have disability progression,” Dr. Karl Kieburtz, the panel’s chairman, told Reuter’s news service on Wednesday.

What remains to be seen, if the drug is allowed back on the market, is whether the risk of developing PML increases with increased exposure to Tysabri. Patients receiving the drug will have to be closely monitored.

It is a risk Leanne Bartlett of Omak, Wash., is willing to take.

The 51-year-old woman who was diagnosed with MS in 1991 said she will be asking her doctor, Kanter, about Tysabri soon. Bartlett received only one dose of the drug before it was recalled three days later, but she said it helped her for up to six months.

“I have problems with fatigue, and it made me feel better that way,” Bartlett said.

However, Wendy Hahn, 41, of Post Falls said she is leery of a drug that has been recalled by the FDA.

“I went through so much to get qualified for Tysabri, and then they pulled it pretty quickly,” Hahn said. “That was enough warning for me.”