Comparison of Fingolimod and Dimethyl fumarate effects on lymphocytes in patients with multiple sclerosis

Abstract

Background: The relationship between lymphopenia resulting from treatment in multiple sclerosis (MS) and the effect of drug treatments is not yet fully known. To date, few studies have been conducted on hematological disorders in patients with MS who have been treated with dimethyl fumarate or fingolimod, as well as the effect of these drugs on the number of lymphocytes and leukocytes.

Methods: This observational cross-sectional study was performed on 80 patients with MS aged ≥ 18 years, who were diagnosed based on the symptoms and treated with dimethyl fumarate or fingolimod in the Neurology Clinic of Imam Khomeini hospital of Urmia in 2021. Patients were categorized according to the type and severity of MS based on the Expanded Disability Status Scale (EDSS). We selected 80 patients in equal groups taking Fingolimod or Dimethyl fumarate. For all patients, complete blood count (CBC) and absolute lymphocyte count (ALC) were calculated at the beginning of treatment, the third and sixth months.

Results: The results of this study showed that in the 6th month, patients treated with fingolimod were more likely to have grade III or IV lymphopenia (P<0.001) and a decrease in the mean percentage of lymphocytes (P>0.001). Patients treated with dimethyl fumarate were more likely to have grade II lymphopenia than the other group (P<0.001).

Conclusion: Treatment with both fingolimod and dimethyl fumarate in patients with MS can lead to lymphopenia in patients, although this lymphopenia was more severe in patients treated with fingolimod.