WEDNESDAY, Feb. 13 (HealthDay News) -- A drug originally
designed to combat cancer that is now being used to treat
autoimmune diseases such as rheumatoid arthritis and lupus might
also work against a common form of multiple sclerosis.
In new research published in the Feb. 14 issue of the
New England Journal of Medicine, researchers reported that
one treatment with rituximab significantly reduced the number of
inflammatory lesions in the brains of people with
relapsing-remitting multiple sclerosis (MS), and almost halved the
incidence of relapse for up to 48 weeks.
"The immediate results of this study should give great hope to
all of us in the field and to our patients," said study author Dr.
Stephen Hauser, chairman of the department of neurology at the
University of California, San Francisco. "An easily-administered,
relatively safe IV therapy might have a very important, profound
effect on the relapsing-remitting phase of MS."
However, Hauser was quick to caution, "these results are
preliminary and should not be translated into a belief that a new
proven therapy has been identified." He said that larger, longer
studies need to be done to fully assess the drug's safety and
efficacy in people with MS.
"We are cautiously optimistic," Dr. John Richert, executive vice
president of research and clinical programs for the National
Multiple Sclerosis Society, said of the findings. "It's hard to
imagine results any better than this, but right now, we don't have
any long-term data on safety or efficacy."
MS is an autoimmune disease that affects the central nervous
system. Instead of targeting foreign invaders, such as bacteria,
the body mistakenly attacks the protective covering of nerve cells
called myelin.
Most research has focused on the T-cell side of the immune
system, but other studies began to suggest that maybe T-cells
weren't the major players in MS after all, and that perhaps B-cells
might play a role. Rituximab, sold under the brand name Rituxan,
targets and depletes a type of B-cell known as CD20+.
Hauser's study included 104 people with relapsing-remitting
multiple sclerosis. Someone with this type of MS will have disease
flare-ups but will also have periods of remission when they don't
have symptoms.
The volunteers were randomly assigned to receive either 1,000
milligrams of intravenous rituximab or a placebo. Magnetic
resonance imaging (MRI) was conducted at 12, 16, 20 and 24 weeks to
assess the number of inflammatory lesions -- a hallmark of MS --
present in the brain.
The number of lesions was reduced in people taking rituximab,
and they also had fewer new lesions than those taking a placebo,
both during the study and six months later.
The rate of relapse was also significantly reduced for those on
rituximab. At the end of the 48-week study period, 20.3 percent of
those on rituximab had experienced a relapse versus 40 percent of
those on placebo.
What both Hauser and Richert found most exciting was the speed
at which rituximab worked and the duration of the benefit, which
continued long after the treatment had been administered.
"Beneficial effects were seen by four weeks," said Richert.
"Among the reasons why these data are so exciting is that the
effects persist after 48 weeks after one course of rituximab."
People taking rituximab did experience more side effects, though
most of them were minor. "The big question is whether removal of
B-cells will impact the immune system later," said Hauser.
Both Hauser and Richert said this study has also provided new
information about the MS disease process, and it will likely open
up additional avenues of MS research.
More information
The National Multiple Sclerosis Society details the
current treatments for the disease.
