Cancer Drug May Ease Rheumatoid Arthritis
New Approach in Rheumatoid Arthritis Treatment Targets Specific Immune Cells
June 18, 2004 -- Short-term rheumatoid arthritis treatment with
a drug that targets a certain type of immune cell may provide lasting
A new study shows adding two doses of the cancer drug Rituxan
to traditional rheumatoid arthritis treatments significantly reduced symptoms
of the painful joint disease for up to 48 weeks.
Rituxan is a biologic drug that targets and destroys particular
cells within the immune system known as B-cells (or B-lymphocytes), which are
thought to play a role in joint inflammation caused by rheumatoid arthritis.
Rituxan is currently used to treat a form of non-Hodgkin's lymphoma caused by
cancerous B-cells, and is manufactured by Genetech, Inc., a WebMD sponsor.
"The 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," says researcher Jonathan
Edwards, MD, of the University College of London, in a news release.
Rituxan May Offer New Type of Rheumatoid Arthritis Treatment
In the study, researchers looked at the effects of two doses of
Rituxan, given by intravenous infusions two weeks apart, in 161 people with
moderate to severe rheumatoid arthritis. All of the participants had previously
been treated with methotrexate, a drug commonly used to treat rheumatoid
arthritis, but still had active rheumatoid arthritis.
The participants were randomly assigned to receive methotrexate
plus a placebo, Rituxan plus a placebo, or Rituxan in combination with
methotrexate or cyclophosphamide, another cancer drug also used as a rheumatoid
arthritis treatment. Each participant also was given a short course of
After six months, more than 40% of those on Rituxan in
combination with methotrexate or cyclophosphamide experienced a 50% improvement
in rheumatoid arthritis symptoms compared with only 13% of those that received
methotrexate alone. Rituxan alone was also more effective than methotrexate at
Those beneficial effects lasted for another six months without
additional treatments -- the length of the study.
In an editorial that accompanies the study, George C. Tsokos,
MD, of the Walter Reed Medical Army Institute of Research, says the findings
support the notion that B-cells play an important role in rheumatoid
Tsokos says successful rheumatoid arthritis treatment with
drugs that target specific immune cells, such as Rituxan, will likely involve
continuing these drugs and possibly use of additional drugs to suppress the
immune system. Therefore, people using these rheumatoid arthritis treatments
should be closely monitored for loss of immune function, which could raise the
risk of infection.
In Edwards' study, serious infections were about equal (3%) in
all groups -- those taking methotrexate plus a placebo and those taking