ORLANDO – In patients with secondary-progressive multiple sclerosis, rituximab could potentially stabilize or reverse the rate of disease progression, according to a small, retrospective, single-center study.
Given the findings, rituximab, a B-cell depletion therapy, is a reasonable option for patients with secondary-progressive multiple sclerosis (SPMS) who no longer respond to primary and secondary lines of treatment, said Christopher M. Perrone, a fourth-year medical student at the University of Massachusetts, Worcester.
Mr. Perrone presented his poster at the fifth Cooperative Meeting of the Consortium of Multiple Sclerosis Centers and the Americas Committee for Treatment and Research in Multiple Sclerosis.
Patients with SPMS have few treatment options. The only FDA-approved therapy for SPMS is mitoxantrone, which, because of severe side effects, is used only after patients stop responding to first and second-line treatments.
Phase I and II studies have shown rituximab’s safety in relapsing-remitting MS. The National Institute of Neurological Disorders and Stroke is recruiting patients for a double-blind, placebo-controlled, single center, phase I/II study on the safety and efficacy of combined systemic and intrathecal rituximab in patients with SPMS.
Mr. Perrone’s review of 25 patients at the University of Massachusetts Multiple Sclerosis Center showed that the disability score for patients with SPMS treated with rituximab for 2 years either stabilized or improved in 84% of the patients.
Four patients (16%) did not respond to rituximab and their disease continued to progress.
Mr. Perrone and his colleagues evaluated the Expanded Disability Status Scale (EDSS), 25-foot walk, and nine-hole peg test scores for 30 patients who were on rituximab therapy for 2 years.
Inclusion criteria were diagnosis of SPMS, at least two cycles of rituximab therapy (each treatment cycle included 1g rituximab IV, 2 weeks apart), and records of the three primary outcomes analyzed in the study.
There were 13 men and 17 women, mean age 56 years, with an average disease duration of 12 years. Five patients were later excluded.
Researchers obtained patient scores 2 years before rituximab therapy to establish rate of progression, and they obtained scores 1 year before treatment to establish baseline. The study had no control groups.
Results showed that 2 years before rituximab therapy, there were statistically significant increases in EDSS scores (0.5 points per year; P = .02), Mr. Perrone and his colleagues reported. However, after the therapy began, there were no significant differences, when compared with baseline values in the majority of the patients (less than 0.1-point increase between first and second treatment cycle, and 0.05-point increase between second and third treatment cycle), "suggesting that patients were at least stabilized on therapy," the authors reported. The treatment cycles were 6 months apart.
Authors then stratified the patients based on EDSS scores. At 2 years, 12 patients (48%) were stable and showed no change in EDSS score, 9 patients (36%) showed significant improvement in EDSS scores, and, in 4 patients (16%), the disease continued to progress.
The researchers noted that it was interesting to find that patients with higher initial EDSS scores were more likely to stabilize after treatment, while patients with lower initial EDSS scores were more likely to exhibit a significant change in EDSS.
There were no changes in MRI activity throughout the course of treatment, except for a nonenhancing lesion in one patient. The reported adverse events, including UTI, rash, fatigue, headache, and serum sickness disease, were not severe.
Mr. Perrone said that given the limited options available, rituximab should be considered an option for patients who have failed primary and secondary therapy, and that the study’s findings were encouraging.
His study has not been published and he said that larger studies are needed to confirm the findings.
Mr. Perrone had no disclosures. The study was funded by a grant from the Foundation of the Consortium of Multiple Sclerosis Centers’ MS Workforce of the Future program.
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