Alemtuzumab therapy is highly effective and safe through 5 years in patients with relapsing-remitting multiple sclerosis (MS), according to findings published in the journal Neurology.
Patients with MS who participated in the CARE-MS I trial (ClinicalTrials.gov identifier NCT00530348) — a randomized, active-controlled trial that compared alemtuzumab at baseline and 12 months with subcutaneous interferon beta-1a in treatment-naive, relapsing-remitting MS — entered the extension trial (ClinicalTrials.gov identifier NCT00930553), which included as-needed retreatment with alemtuzumab for relapsing MS or disease activity on MRI.
A majority of people with MS treated with alemtuzumab in CARE-MS I (95.1%) also enrolled in the extension study, and 96% of them remained with the study through 5 years. During years 3, 4, and 5, the annualized relapse rate stayed low (0.19, 0.14, and 0.15, respectively). Throughout the 5-year period, 79.7% of patients had no 6-month confirmed disability worsening, and 33.4% had 6-month confirmed disability improvement.
More than half of patients had no evidence of disease activity at 3, 4, and 5 years (61.7%, 60.2%, and 62.4%). Researchers noted a median annual improvement in brain volume loss during years 2 through 4 (years 1-5: 0.59%, 0.25%, 0.19%, 0.15%, and 0.20%). Relative to the core study, the exposure-adjusted incidence of adverse events decreased in the extension study.
Investigators comment that there was no continuation of the active comparator design of the CARE-MS trial through the extension period, limiting a long-term comparison with another treatment. Despite this limitation, the authors note that alemtuzumab “demonstrate[s] durable, long-term therapeutic effects on clinical disease activity measures, as well as on more objective measures such as MRI lesion activity and brain atrophy.”
Havrdova E, Arnold DL, Cohen JA, et al; on behalf of the CARE-MS I and CAMMS03409 Investigators. Alemtuzumab CARE-MS I 5-year follow-up: durable efficacy in the absence of continuous MS therapy. Neurology. 2017;89:1107-1116.