PHILADELPHIA—Alemtuzumab may prevent disease activity for as long as three years in patients with active relapsing-remitting multiple sclerosis (MS), according to research presented at the 66th Annual Meeting of the American Academy of Neurology.
The drug appears to suppress gadolinium-enhancing activity and new or enlarging T2 lesions efficiently among treatment-naïve patients and patients who have relapsed on previous therapy. In addition, alemtuzumab reduces brain volume loss to a rate similar to that associated with normal aging, said Douglas Arnold, MD, a neurologist at the Montreal Neurological Institute and Hospital.
Douglas Arnold, MD
Dr. Arnold and colleagues presented three-year MRI outcomes from the Comparison of Alemtuzumab and Rebif Efficacy in MS (CARE-MS) I and II trials, which lasted for two years. CARE-MS I included treatment-naïve participants, and CARE-MS II included participants who had relapsed on prior therapy. In both trials, patients with MS were randomized to alemtuzumab or interferon beta-1a. Patients randomized to alemtuzumab received 12 mg at baseline and at one year. In CARE-MS I, alemtuzumab reduced relapse rates, compared with interferon beta-1a. In CARE-MS II, alemtuzumab reduced relapse rates and sustained accumulation of disability, compared with interferon beta-1a.
Alemtuzumab Slowed the Rate of Brain Atrophy
A total of 349 participants in CARE-MS I and 393 participants in CARE-MS II entered the extension trial. At year three, the researchers administered alemtuzumab again to patients with recurrence of disease activity. Approximately 18% of patients in CARE-MS I and 20% of patients in CARE-MS II had recurrence. Fewer than 3% of patients had taken any other therapy at year three.
“At year three, patients maintained approximately 90% suppression of gadolinium-enhancing activity and about 75% suppression of new or enlarging T2 lesion formation,” said Dr. Arnold. Similar proportions of patients had new or active gadolinium-enhancing lesions at year three and at year two (9.6% and 7.1%, respectively). Also, similar proportions of patients had new and enlarging T2 lesions at year three and at year two (27.4% and 23.1%, respectively). Approximately 75% of patients in both trials had no MRI activity.
The rate of change in brain volume slowed progressively from year one to year three. At year three, the rate of change was 0.19% per year in CARE-MS I and 0.1% per year in CARE-MS II.
Positive Outcomes Despite Two-Year Lack of Treatment
“These findings provide strong support for the efficacy of alemtuzumab in treatment-naïve patients and patients who have relapsed on prior therapy,” said Dr. Arnold. “It is important to note that the majority of patients in this three-year follow-up received no treatment for two years, since they received their second course of alemtuzumab at the beginning of year two. Despite being treatment-free for two years, they had these remarkable outcomes on MRI.”
—Erik Greb