CONCERN VOICED
Rituxan, known generically as rituximab, is made by the biotechnology companies Genentech Inc. and Biogen Idec Inc., which sponsored the study.
It is approved for non-Hodgkin's lymphoma and rheumatoid arthritis and sold by Roche AG as MabThera outside the United States, Japan and Canada.
Hauser expressed concern that, based on the new results, doctors may begin using the drug on their MS patients even though it has not been approved for that use.
"This trial was not designed to assess long-term safety or to detect uncommon adverse events," the researchers wrote.
"It would be a tragedy if the drug were to get dinged because of a side effect in a patient that shouldn't have received the drug," he said.
The research has also given doctors a better idea of what causes MS, according to Hauser. Rituxan is a monoclonal antibody, a genetically engineered immune system protein, which attacks immune cells called B cells.
"This study has taught us that B cells are absolutely essential to the genesis of inflammatory attacks in multiple sclerosis," Hauser said.
