Tysabri shows promise against Crohn’s disease

The phase III trial known as “Encore” enrolled 510 patients with evidence of active inflammation. The data showed that Tysabri (natalizumab) helped decrease disease activity and promote remission.

Although these results suggest the drug has promise for the treatment of bowel disease, fears surrounding the drug’s safety have not diminished. In February 2005 Tysabri, which was originally indicated for the treatment of multiple sclerosis, was removed from the market following the discovery of a correlation between the use of the drug and the development of a rare and potentially fatal brain disease, progressive multifocal leukoencephalopathy (PML).

Elan and Biogen are still in the process of carrying out a comprehensive evaluation of the safety of Tysabri. The companies said they hope to know the risk/benefit profile of the drug by the end of this summer.

Lars Ekman, executive vice president and president of R&D at Elan said: “Patient safety remains our top priority. We plan to share the data from Encore and our other phase III Tysabri Crohn’s studies with the FDA and other regulatory agencies to determine the appropriate path forward for Tysabri as a potential new treatment option for this underserved patient population.”