Biogen Idec testing Tysabri as a cancer treatment

Biogen Idec Inc. of Cambridge and Elan Corp. plc of Dublin today announced the initiation of the first clinical trial of Tysabri as a potential cancer treatment.

Tysabri is already approved for treating multiple sclerosis and Crohn's disease, but there have been setbacks. Tysabri was originally launched in 2004 but was temporarily taken off the market after several multiple sclerosis patients contracted a brain disease. In mid 2006, Tysabri was reintroduced to the market with strict prescribing guidelines. Several weeks ago, Biogen Idec said that two more patients appeared to have contracted the rare and potentially fatal brain disease, the first cases since Tysabri was reintroduced to the market two years ago.

Speaking about Tysabri as a potential oncology drug, Biogen Idec and Elan said that the first dose of Tysabri was administered yesterday in the trial.

The companies said in a press release, "The objectives of this Phase I/II study are to evaluate the safety and potential anti-tumor activity of Tysabri in patients with relapsed or refractory multiple myeloma."

Having Tysabri approved for cancer treatment would boost Biogen Idec and Elan, which share the rights to Tysabri, and widen the market for the drug.

Last month, before the two companies announced plans to test Tysabri as a potential cancer treatment, a Wall Street analyst said that even under his best scenario, Tysabri will have only about 75,000 users by 2013, short of Biogen Idec's goal of 100,000 by 2010.

In January, Tysabri won US regulatory approval as a treatment for Crohn's disease, a debilitating disease that frequently causes diarrhea and abdominal cramps as well as fever, bleeding, and weight loss.

For additional coverage of Tysabri, please click here.
(By Chris Reidy, Globe staff)