Rituxan Shows Promise for MS
Cancer, Arthritis Drug May Help People With Multiple Sclerosis
T Cells and B Cells continued...
By week 24, the Rituxan-treated patients showed 91% fewer lesions, compared with the placebo-treated patients, and the results were similar at week 48.
"What we found so stunning was not only that the drug worked, but that it worked almost immediately," Hauser says.
The patients who got Rituxan showed improvement in lesions with the first post-infusion MRI scan, taken just weeks after treatment ended.
"This could only have happened if the B cells themselves are the culprit and not the antibody," he says. "It sends us back to the lab to discover what it is about the B cell, independent of its impact on antibodies, that is at the center of what causes MS flares."
Rituxan Safety Concerns
Hauser says there were few treatment-related side effects among the patients in the study, but questions about the long-term safety of Rituxan remain.
Rituxan is approved for the treatment of non-Hodgkin's lymphoma (NHL) and rheumatoid arthritis.
Use of the drug has been linked to a rare but fatal brain infection known as progressive multifocal leukoencephalopathy (PML). But it is not clear if PML is caused by the drug or by the patients' underlying disease.
Until more is known and until Rituxan is approved for the treatment of MS, patients with multiple sclerosis should not use it, says John Richert, MD, the National Multiple Sclerosis Society's executive vice president for research and clinical programs.
"We really want to discourage off-label use," he tells WebMD. "We just don't know enough about its long-term safety."
But Richert agrees that the early findings offer the hope of a new direction in the study and treatment of MS.
"Within the limitations of what you would expect with a small trial of short duration, the (UCSF) results are very exciting," he says. "We are cautiously optimistic that the phase III trials will show the same degree of efficacy."