The study implies that B-cell depletion by rituximab therapy may be therapeutically beneficial in patients with secondary progressive multiple sclerosis.
Since limited treatment options still exists for patients with secondary progressive multiple sclerosis (SPMS), a team of investigators decided to compare rituximab therapy in SPMS patients to matched control patients in an effort to evaluate the therapy’s potential for the disease.
Among the results, the team observed a significantly lower EDSS score for up to 10 years of follow-up and a significantly delayed confirmed progression in patients with SPMS who were administered rituximab compared with match controls, suggesting the therapy may be beneficial for patients with SPMS.
In a retrospective cohort study, a team of investigators analyzed data from patients with SPMS from 2004-2017 at 3 multiple sclerosis centers in Basel, Lugano, Switzerland, Amsterdam, and the Netherlands. Progression of EDSS score after baseline served as the primary endpoint while time to confirmed disability progression served as the secondary endpoint.
All patients had a diagnosis of SPMS, were treated (57 eligible; 54 included) or never treated (504 eligible; 59 included) with rituximab, and had at least 1 follow-up visit. Sex, age, Expanded Disability Status Scale (EDSS) score, and disease duration were used as variables for propensity score matching. In the total cohort, the follow-up duration was up to 10 years and had a mean (SD) of 3.5 (2.6) years for rituximab-treated patients and 5.4 (2.4) years for controls. In the matched cohort, the follow-up duration was also up to 10 years with a mean (SD) of 3.5 (2.7) years for rituximab-treated patients and 4.8 (2.2) years.
By using propensity score matching, the team compared EDSS score progression in patients with SPMS who were administered rituximab versus those not administered rituximab. The study authors noted this as an exposure.
According to the results, patients administered rituximab at baseline had a mean (SD) age of 49.7 (10) years, mean (SD) disease duration of 18.2 (9.4) years, and mean (SD) EDSS score of 5.9 (1.4); 26 (59%) were women. Controls had a mean (SD) age of 51.3 (7.4) years, mean (SD) disease duration of 19.4 (8.7) years, and mean (SD) EDSS score of 5.7 (1.29); 27 (61%) were women.
In addition, patients with SPMS who were administered rituximab in the covariate-adjusted analysis of the matched set had a significantly lower EDSS score during a mean (SD) follow-up of 3.5 (2.7) years (mean difference, −.52; 95% CI, −.79 to −.26; P < .001).
Study authors noted that, “Time to confirmed disability progression was significantly delayed in the rituximab-treated group (hazard ratio, .49; 95% CI, .26-0.93; P = .03).”
Overall, a significantly lower EDSS score for up to 10 years of follow-up and a significantly delayed confirmed progression compared with matched controls were experienced by patients SPMS who were administered rituximab, implying that B-cell depletion by rituximab may be therapeutically beneficial in these patients.
The team concluded that in order to confirm the efficacy of rituximab in this patient population, they need to conduct a prospective randomized clinical trial with a better level of evidence.
The study, titled, “Association of Rituximab Treatment With Disability Progression Among Patients With Secondary Progressive Multiple Sclerosis,” was published in the Journal of the American Medical Association (JAMA).