FDA has approved alemtuzumab (Lemtrada, Genzyme, A Sanofi Company) for the treatment of patients with relapsing forms of multiple sclerosis (MS).
Alemtuzumab is administered by intravenous infusion for 5 consecutive days initially, and then for 3 consecutive days a year later. Given its safety profile, the drug should be reserved in general for those patients who have previously had an inadequate response to at least 2 other drugs indicated for the treatment of MS.
Results from 2 large, randomized phase 3 studies, CARE-MS I and CARE-MS II, form the basis for the approval by FDA. Both studies showed that alemtuzumab was found to significantly reduce annualized relapse rates in MS patients over the course of two years as compared with standard subcutaneous dosing of interferon beta-1a (Rebif, EMD Serono). The second study, CARE-MS II, also found the possibility that alemtuzumab may significantly reduce the worsening of disability in these patients.
A total of 563 patients with early, active relapsing-remitting MS new to treatment were enrolled in CARE-MS I; the relapse rate for those on alemtuzumab was reduced by 55% versus those on interferon beta-1a after 2 years. Of the 628 patients enrolled in CARE-MS II who had relapsed on prior therapy, 35% administered alemtuzumab had a relapse, as compared with 51% of those on interferon beta-1a. This constituted a 49.4% lower risk of relapses with the use of alemtuzumab.
In MS, immune-system attacks occur to the brain and spinal cord tissues. The disease is diagnosed in most persons between the ages of 20 and 50 years, affecting at least 2 to 3 times more women than men. Approximately 400,000 individuals are living with MS in the United States today. Worldwide, MS is estimated to affect more than 2.3 million people.
The full results for CARE-MS I and CARE-MS II can be found in the Lancet (2012;380:1819-1828; 1829-1839).