Tysabri AgainFDA Halts MS Drug Trial in Wake of Tysabri

Information from Industry
Assess clinically focused product information on Medscape.
Click Here for Product Infosites -- Information from Industry.


By Ben Hirschler

LONDON (Reuters) Mar 16 - GlaxoSmithKline Plc said on Wednesday U.S. regulators have halted clinical trials of multiple sclerosis drugs in the same class as recently withdrawn treatment natalizumab (Tysabri), including its experimental drug '699.

Tysabri, which was developed by Ireland's Elan Corp Plc and U.S.-based Biogen Idec, was pulled from the market on February 28th after a patient died from a rare and often fatal CNS infection.

Both Tysabri and '699, which GSK is developing with Japan's Tanabe Seiyaku Co Ltd, work by inhibiting alpha-4 integrin, a substance implicated in the disease.

"The FDA has taken the precautionary measure of placing a clinical hold on investigational new drugs in the alpha-4 integrin antagonist class being tested on human subjects, which includes '699," a GSK spokesman said.

GSK said it was not aware of any problems with its drug similar to those experienced with Tysabri. "Whilst '699 has the same molecular target as natalizumab (Tysabri), '699 is chemically unrelated to natalizumab," the spokesman said.

GSK and Tanabe's drug is taken as a pill while Tysabri is given as a monthly infusion.

GSK had been expected to report phase II trial results with '699 by the end of this year, ahead of an anticipated filing for regulatory approval in 2008.