Scientists at Britain's University of Cambridge have found that a drug originally developed to treat leukemia may prove useful in the treatment of multiple sclerosis (MS).

Professor Alastair Compston and colleagues conducted the three-year-long study on 334 patients with relapsing-remitting MS. Results showed that alemtuzumab cut the number of attacks experienced by participants by 74% more than that achieved by interferon-beta-1a therapy, the current treatment of choice.

Furthermore, many of the study participants who received alemtuzumab recovered some of their lost functions, and were therefore less disabled at the end of the three-year-long study than they were at the beginning. On the other hand, participants who were treated with interferon beta-1a were more disabled by the end of the study. The researchers say that their findings suggest that alemtuzumab may promote brain repair, thus enabling the recovery of neurological functions lost in previous attacks of the disease.

However, alemtuzumab can cause serious side effects. One in five participants treated with alemtuzumab developed an over- or under-active thyroid gland, and 3% developed immune thrombocytopenic purpura, a condition that leaves patients vulnerable to bleeding. However, the researchers note that while this complication is potentially very serious, it is easily treated if identified early.

In a news release issued by the University of Cambridge, Professor Compston said: "Alemtuzumab is the most promising experimental drug for the treatment of multiple sclerosis, and we are hopeful that the Phase 3 trials will confirm that it can both stabilize and allow some recovery of what had previously been assumed to be irreversible disabilities.”

The CAMMS223 Trial Investigators. Alemtuzumab vs. interferon beta-1a in early multiple sclerosis. NEJM. 2008;359:1786-1801.

News release: New hope for multiple sclerosis sufferers. University of Cambridge Website. October 22nd 2008.