Rituxan fails in tests to treat lupus

NEW YORK Genentech and Biogen Idec reported Wednesday that their jointly marketed drug Rituxan failed to show effectiveness in battling lupus, according to published reports.

Lupus, an autoimmune disease suffered by an estimated 1.5 million Americans, has no cure and the treatments currently prescribed for it—decades-old immune-suppressing agents—are plagued with serious side effects. The disease, which is caused by a malfunctioning immune system that can attack multiple organs, is potentially fatal and disproportionately affects women of childbearing age.

"We are disappointed in the results," Hal Barron, Genentech's chief medical officer, said in a statement, according to the Wall Street Journal. "But we understood from the outset the significant challenges in developing treatments for systemic lupus erythematosus."

Rituxan, which had U.S. sales of $2.3 billion last year, is already approved to treat rheumatoid arthritis and a form of blood cancer. Genentech and Biogen Idec have been trying to broaden the drug's uses, though the companies announced earlier this month that it also failed to treat a severe form of multiple sclerosis. They do report that they are still in the process of conducting a separate trial on lupus nephritis, which occurs when the disease attacks the kidney.

Success with any added utilization of Rituxan could spell additional sales in the hundreds of millions of dollars per year for the partnership.