Effects of disease-modifying therapy on peripheral leukocytes in patients with multiple sclerosis

Abstract

Modern disease-modifying therapies (DMTs) in multiple sclerosis (MS) have variable modes of action and selectively suppress or modulate the immune system. In this review, we summarize the predicted and intended as well as unwanted adverse effects on leukocytes in peripheral blood as a result of treatment with DMTs for MS. We link changes in laboratory tests to the possible therapeutic risks that include secondary autoimmunity, infections, and impaired response to vaccinations. Profound knowledge of the intended effects on leukocyte counts, in particular lymphocytes, explained by the mode of action, and adverse effects which may require additional laboratory and clinical vigilance or even drug discontinuation, is needed when prescribing DMTs to treat patients with MS.

Long-Term Observation of SARS-CoV-2 Vaccination Response upon High Efficacy Treatment in Multiple Sclerosis—A Real-World Scenario

“…Interestingly and of further relevance to infection and vaccination in pwMS, the proportion of those with hypogammaglobulinemia in our real-world cohort was lower than in previously published studies on ocrelizumab [26]. Furthermore, only 9.1% displayed lymphopenia at any time during our observation period, which is lower than the reported 20.7% in RRMS and 26.3% in PPMS in the approval study, most of those with only mild lymphopenia [51]. However, one must take into account that our real-world cohort did include patients with variable durations of therapy whilst the comparison study was a 5-year follow-up of the approval study.…”

Long-Term Observation of SARS-CoV-2 Vaccination Response upon High Efficacy Treatment in Multiple Sclerosis—A Real-World Scenario

“…Interestingly and of further relevance to infection and vaccination in pwMS, the proportion of those with hypogammaglobulinemia in our real-world cohort was lower than in previously published studies on ocrelizumab [26]. Furthermore, only 9.1% displayed lymphopenia at any time during our observation period, which is lower than the reported 20.7% in RRMS and 26.3% in PPMS in the approval study, most of those with only mild lymphopenia [51]. However, one must take into account that our real-world cohort did include patients with variable durations of therapy whilst the comparison study was a 5-year follow-up of the approval study.…”

Real-world comparison of anti-CD20 therapies: efficacy, infections, and immune profiles in a German cohort

“…This may explain why these had the highest infection rates despite lower rates of hypogammaglobulinemia. As per the literature, lymphopenia develops in approximately 20% of cases under OCR ( 25 , 48 , 49 ). While the available data set is limited, initial findings suggest that the incidence of this is lower with OFA ( 15 , 50 , 51 ).…”

A Retrospective Cohort Study with Blood Parameters for Early Estimation of Multiple Sclerosis: Ratio Suggestion

“…Compared with leukocyte counts, erythrocyte counts are less affected by neuroinflammation caused by MS (22,23). In addition, neuromodulatory drugs used by MS patients may cause changes in the number of leukocyte types (23,24). Consistent with the higher RBC, hemoglobin, hematocrit, and serum Fe values in the MS groups, the RDW value was also higher in the control group.…”

Long-Term Observation of SARS-CoV-2 Vaccination Response upon High Efficacy Treatment in Multiple Sclerosis—A Real-World Scenario

“…Interestingly and of further relevance to infection and vaccination in pwMS, the proportion of those with hypogammaglobulinemia in our real-world cohort was lower than in previously published studies on ocrelizumab [26]. Furthermore, only 9.1% displayed lymphopenia at any time during our observation period, which is lower than the reported 20.7% in RRMS and 26.3% in PPMS in the approval study, most of those with only mild lymphopenia [51]. However, one must take into account that our real-world cohort did include patients with variable durations of therapy whilst the comparison study was a 5-year follow-up of the approval study.…”

Real-world comparison of anti-CD20 therapies: efficacy, infections, and immune profiles in a German cohort

“…This may explain why these had the highest infection rates despite lower rates of hypogammaglobulinemia. As per the literature, lymphopenia develops in approximately 20% of cases under OCR ( 25 , 48 , 49 ). While the available data set is limited, initial findings suggest that the incidence of this is lower with OFA ( 15 , 50 , 51 ).…”

A Retrospective Cohort Study with Blood Parameters for Early Estimation of Multiple Sclerosis: Ratio Suggestion

“…Compared with leukocyte counts, erythrocyte counts are less affected by neuroinflammation caused by MS (22,23). In addition, neuromodulatory drugs used by MS patients may cause changes in the number of leukocyte types (23,24). Consistent with the higher RBC, hemoglobin, hematocrit, and serum Fe values in the MS groups, the RDW value was also higher in the control group.…”

Long-Term Observation of SARS-CoV-2 Vaccination Response upon High Efficacy Treatment in Multiple Sclerosis—A Real-World Scenario

“…Interestingly and of further relevance to infection and vaccination in pwMS, the proportion of those with hypogammaglobulinemia in our real-world cohort was lower than in previously published studies on ocrelizumab [26]. Furthermore, only 9.1% displayed lymphopenia at any time during our observation period, which is lower than the reported 20.7% in RRMS and 26.3% in PPMS in the approval study, most of those with only mild lymphopenia [51]. However, one must take into account that our real-world cohort did include patients with variable durations of therapy whilst the comparison study was a 5-year follow-up of the approval study.…”

Real-world comparison of anti-CD20 therapies: efficacy, infections, and immune profiles in a German cohort

“…This may explain why these had the highest infection rates despite lower rates of hypogammaglobulinemia. As per the literature, lymphopenia develops in approximately 20% of cases under OCR ( 25 , 48 , 49 ). While the available data set is limited, initial findings suggest that the incidence of this is lower with OFA ( 15 , 50 , 51 ).…”

A Retrospective Cohort Study with Blood Parameters for Early Estimation of Multiple Sclerosis: Ratio Suggestion

“…Compared with leukocyte counts, erythrocyte counts are less affected by neuroinflammation caused by MS (22,23). In addition, neuromodulatory drugs used by MS patients may cause changes in the number of leukocyte types (23,24). Consistent with the higher RBC, hemoglobin, hematocrit, and serum Fe values in the MS groups, the RDW value was also higher in the control group.…”