Withdrawn MS drug works for Crohn's sufferers

Nov 3 2005

Researchers say that a multiple sclerosis drug that was withdrawn from the market for safety reasons, has shown some effectiveness against the painful bowel disorder Crohn's disease.

Apparently the drug Tysabri, although it did not work very well against Crohn's in a short-term study, it brought some relief to patients who continued receiving the drug for a year.

The makers of Tysabri, Elan Corp and Biogen IDEC halted sales of the drug in February, months after it was approved for MS, because of fears it may be linked to a rare brain disease.

It seems that three patients taking Tysabri developed the disease and two died.

According to the drug companies, a safety review found no new confirmed cases of the brain disease in patients treated with Tysabri, and are seeking government approval to resume selling the drug which is also called natalizumab.

It is estimated that as many as 500,000 Americans are afflicted with Crohn's disease, the cause of which is unknown and there is currently no cure.

Symptoms include abdominal pain, persistent diarrhea and fever.

Some relief can be achieved with drugs to control inflammation and suppress the immune system.

It seems that Tysabri attaches to the immune cells and prevents them from reaching areas of inflammation.

In their report the researchers show the results of two company-funded international studies of Tysabri for Crohn's.

In the first test, 905 patients got three infusions of Tysabri or a dummy infusion over eight weeks.

The two groups had similar rates of response and remission.

In the second study, 339 patients from the first test who had improved with Tysabri were given either the drug or a dummy infusion every four weeks for a year.

Those who got the Tysabri had higher rates of sustained response (61 percent vs. 28 percent) and remission (44 percent vs. 26 percent).

Dr. Lars Ekman speaking for Elan, says the drug has now been tested in 1,500 Crohn's patients, including those in another yet-unreleased positive trial, and they feel confident that Tysabri will be made available over time as a treatment alternative in Crohn's disease.

However Dr. Daniel Podolsky of Massachusetts General Hospital says not enough is known yet about Tysabri's effectiveness against Crohn's to determine whether the drug is worth the risks.

Meanwhile Dr. Ellen J. Scherl of Weill Medical College of Cornell University, who had patients in the first study, said the research identified some types of patients who may benefit most from Tysabri.

She feels it would be a loss for not to have this as an option for patients.

The research is published in the current edition of the New England Journal of Medicine.