Five year follow-up results published for Alemtuzumab

The results of the phase III trial of alemtuzumab and five year follow-up results were presented at the conference of the European Committee For Treatment and Research in Multiple Sclerosis (ECTRIMS) in October 2011, and released in a company announcement made on 14 November.

The five year follow-up results have now been published in Neurology (21 March 2012).

Alemtuzumab 12 mg was given daily as an IV administration for 5 days, and then again for 3 days one year later. It was compared to sub-cutaneous injections of interferon beta-1a three times a week over the two years of the phase III study. In the randomized trial involving 840 patients, a 49% reduction in relapse rate was observed in patients treated with alemtuzumab compared to interferon. The difference was highly statistically significant (p<0.0001). There was also a 42% reduction in the risk of sustained worsening of disability as measured by the Expanded Disability Status Scale (EDSS).

Results of the five year follow-up  showed that relapse rates were not only reduced by alemtuzumab in early aggressive cases of MS compared to interferon treatment, but the effects were sustained to the five year time point.

Alemtuzumab has some significant side-effects such as opportunistic infections and secondary-autoimmune thyroiditis. These can be picked up early with careful monitoring and standard treatments are effective.

Alemtuzumab is a monoclonal antibody, currently used for the treatment of some types of leukaemia. It targets the cell-surface protein CD52, which is largely found on T- and B-lymphocytes. Preliminary research suggests that alemtuzumab initially depletes the T- and B-cells that may be responsible for the cellular damage in MS. This is later followed by a repopulation of the immune system, but the proportions of different cell types remain different from the original baseline immune system.

Alemtuzumab appears to be a promising new treatment, but is not without significant side effects.

It will still be some time before this therapy can pass through the regulatory frameworks for new medicines.

Updated 27 March 2012