Biogen Idec, Genentech Gain on Arthritis Study

Rituxan does more than just fight cancer -- the blockbuster drug, co-marketed by Genentech (DNA Quote) and Biogen Idec (BIIB Quote) in the U.S., also shows promise as a rheumatoid arthritis treatment, according to a new study.

A study published in the New England Journal of Medicine said that two doses of Rituxan, given two weeks apart, improved symptoms in 70% of arthritis sufferers for up to 48 weeks when combined with a common arthritis treatment called methotrexate, or MTX. In reaction, shares of Biogen rose 30 cents, or 0.5%, to $60.07, while Genentech rose 61 cents, or 1.1%, to $54.56.

Rituxan, which was approved for the treatment of non-Hodgkin's lymphoma in 1997, depletes B-cells, which make the antibodies that cause inflammatory conditions like arthritis.

"This study provides support for the concept that B-lymphocytes play a central role in rheumatoid arthritis and suggests that B-lymphocyte targeted therapy has potential," said Jonathan Edwards of the University College of London, lead investigator of the study.

In the study, 73% of patients saw improvement in their condition after 24 weeks when adhering to treatment combining Rituxan and MTX. After 48 weeks, long after patients had stopped taking Rituxan and MTX, 65% saw continued improvement in their condition.

"Rheumatoid arthritis affects over 2 million Americans, and despite recent advances in therapy, many patients do not respond or respond inadequately to current treatments," said Burt Adelman, executive vice president of development at Biogen. "By selectively targeting B-cells, Rituxan may offer an entirely new approach to treating rheumatoid arthritis."

With a successful phase IIa study completed, Biogen and Genentech are pushing forward with a phase IIb dose optimization study for patients who do not respond to antirheumatic drugs currently on the market.

At the same time, the companies said they will start phase III testing of Rituxan as a rheumatoid arthritis treatment in patients who did not respond to tumor necrosis factor inhibitor therapies.

Biogen and Genentech's success with Rituxan comes in the wake of Neurogen's (NRGN Quote) disappointing drug trial. On Wednesday, Neurogen's shares plunged after the Connecticut-based drugmaker announced that preliminary testing of its rheumatoid arthritis treatment, NGD 2000-1, failed to live up to expectations.