Introduction: Multiple sclerosis (MS) patients of African descent have increased risk for disease progression and may be less responsive to disease-modifying therapy.
Methods: Patients in the CARE-MS studies received alemtuzumab 12 mg/day [initial alemtuzumab treatment (IAT); baseline: 5 days; 12 months later: 3 days] or subcutaneous interferon beta-1a (SC IFNB-1a) 3 ×/week. Core study outcomes were compared between treatment groups. In the extension study CAMMS03409, SC IFNB-1a-treated patients switched to alemtuzumab [delayed alemtuzumab treatment (DAT)]. Data from IAT and DAT arms were pooled to assess outcomes through 6 years post alemtuzumab initiation; IAT patients had an additional 2 years of follow-up in TOPAZ.
Results: Of 1200 CARE-MS patients, 43 (4%) were of African descent (35 IAT; 8 DAT) and received alemtuzumab in the 2-year core and/or 6-year extension; 29 (67%) remained on study at the time of analysis (24 IAT patients completed year 8 post alemtuzumab; 5 DAT patients completed year 6 post alemtuzumab). In year 2, annualized relapse rate (ARR; 0.09 versus 0.42), percentage of patients with improved Expanded Disability Status Scale (EDSS; 18% versus 11%), 6-month confirmed disability improvement (CDI; 28% versus 13%), no evidence of disease activity (55% versus 13%), and cumulative brain volume loss (BVL; - 0.55% versus - 1.32%) favored alemtuzumab versus SC IFNB-1a. Alemtuzumab remained efficacious at year 6 (pooled IAT/DAT) and at year 8 (IAT only) post alemtuzumab (ARR: 0.15 and 0.30; improved EDSS: 17% and 25%; CDI: 47% and 55%; BVL: - 1.14% and - 0.70%, respectively). No safety signals were unique to this population.
Conclusions: Alemtuzumab was efficacious in a small cohort of relapsing-remitting MS patients of African descent over 8 years. Safety was consistent with the overall CARE-MS population, although the small sample size may have prevented the detection of known low-frequency adverse events. CLINICALTRIALS.
Funding: Sanofi (Cambridge, MA, USA) and Bayer HealthCare Pharmaceuticals (Leverkusen, Germany).
Keywords: African descent; Alemtuzumab; Disease-modifying therapy; Multiple sclerosis.