Rituxan Treats Rheumatoid Arthritis
Study Shows Low Doses of Rituxan as Effective as Higher Doses
WebMD News Archive
April 28, 2006 -- A cancerdrug
that has a unique mode of action is showing promise in the treatment of rheumatoid arthritis.
Rituxan is the first drug to target a specific B immune cell, believed to
play a role in inflammation in rheumatoid arthritis (RA) patients. It was approved two
months ago by the FDA for use by rheumatoid arthritis patients who have failed
treatments. Rituxan is administered as an infusion into a vein.
Just over half of the RA patients in a new study saw their symptoms improve
when treated with Rituxan in combination with the disease-modifying
antirheumatic drug (DMARD) methotrexate.
Patients taking low doses of Rituxan responded as well as those given higher
doses, and the addition of steroids during treatment did not appear to improve
All of the patients in the study had previously failed treatment with
methotrexate or other DMARDs. About a third had been treated with biologic
agents that work via a different pathway, such as the drugs Enbrel, Humira, and
The findings suggest that patients may do equally as well on low doses of
the drug as on high doses. But researcher Roy Fleischmann, MD, of the
University of Texas Southwest Medical Center, says it is still too early to say
this for sure.
"We don't yet know if responses last longer with higher doses or if the
depth of response is better with different dosing," Fleischmann tells
WebMD. "Studies involving larger numbers of patients are being done to
answer these questions."
An estimated 3 million adults in the U.S. have rheumatoid arthritis, a progressive autoimmune
disease that involves inflammation of the joints and surrounding tissues. Over
the years, RA can destroy joints, ligaments, tendons, and even bone.
Biologic drugs that suppress inflammation-causing immune system cells, or
cytokines, are new to the treatment of rheumatoid arthritis. While very expensive -- costing
between $16,000 and $20,000 a year, according to one cost analysis -- they hold
the promise of eliciting better outcomes than traditional RA treatments with
fewer side effects.
The study of Rituxan included 465 patients with moderate to severe RA
treated with Rituxan or placebo plus methotrexate -- with and without