NATIONAL HARBOR, MD. – A subgroup analysis of 46 patients of African descent with active relapsing-remitting multiple sclerosis (RRMS) from the CARE-MS I and CARE-MS II trials has demonstrated the efficacy of alemtuzumab over 5 years.
The long-term results implicate alemtuzumab as a valuable treatment option for RRMS patients of African descent. These patients are at higher risk of more severe disease.
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“In patients of African descent, alemtuzumab had clinical and [magnetic resonance imaging] efficacy comparable with that observed in the overall CARE-MS study population. Efficacy was durable over 5 years, with the majority of patients not receiving alemtuzumab treatment after month 12,” Dr. Annette Okai of the Multiple Sclerosis Treatment Center of Dallas reported at the annual meeting of the Consortium of Multiple Sclerosis Centers.
Patients of African descent have a heightened risk of MS that is more severe and more rapidly debilitating than that of white patients. As well, disease-modifying therapies may not be as effective in this group. To seek a better treatment option, Dr. Okai and colleagues performed a subgroup analysis involving the alemtuzumab treatment arm of the CARE I and II phase III randomized trials.
In CARE-MS I and II, a total of 811 patients received two annual intravenous injections of 12 mg alemtuzumab during the 2-year core phase of the trial and as-needed treatment during the extension phase from years 3 to 5. The trial cohort comprised 46 patients of African descent (80% from the United States, 76% female). Thirty-two of the 46 patients entered the extension phase.
Of the 32 patients, 17 (53%) did not receive retreatment beginning in year 2, and 28 (88%) did not receive another disease-modifying treatment. The efficacy of alemtuzumab in the overall CARE-MS cohort and in patients of African descent was durable over the full 5 years of the study. In those of African descent, the cumulative 0- to 5-year annualized relapse rate was 0.16. Sixty percent of the patients of African descent were relapse free in years 3-5.
Disease severity as measured by Expanded Disability Status Scale scores did not change appreciably over the 5 years (mean change, +0.52). No evidence of disease activity (NEDA) was observed in 33% of alemtuzumab patients in years 0-2, compared with 13% of those in the subcutaneous interferon beta-1a arm of CARE-MS I and II. Rates of NEDA in year 3, 4, and 5 were 45%, 42%, and 56%, respectively, and NEDA was achieved by 25% of the patients of African descent from years 3 to 5.
There were no serious infusion-associated reactions in the patients of African descent and the safety profile was similar to the overall cohort.
The efficacy and durability of alemtuzumab in the overall cohort generally, and in the patients of African descent more particularly, could reflect immunomodulation that is linked to lymphocyte repopulation, Dr. Okai suggested.
“Based on these findings, alemtuzumab may provide a unique treatment approach with durable efficacy in this high-risk population,” she concluded.
The studies were sponsored by Genzyme and Bayer Healthcare Pharmaceuticals. Dr. Okai disclosed receiving consulting fees from Genzyme, Novartis, Teva, Genentech, Biogen, and EMD Serono.