Neutropenia after ocrelizumab treatment in patients with multiple sclerosis: A single-centre case series and systematic review of literature.

INTRODUCTION

Neutropenia is a rare side effect of CD20-depleting therapy and information regarding its management is scarce. This study aims to evaluate the clinical features, management and prognosis of ocrelizumab-related neutropenia in MS patients.

METHODS

Retrospective single-centre case series and systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

37 patients were included (2 from our centre, representing an incidence of 0.63% per patient-year in our cohort [N = 117]; and 35 from the systematic review). Mean age was 36.2 years (SD 8.24) and 67.6% were female. Median number of previous disease-modifying drugs was 1 (IQR 2). Neutropenia occurred in a median of two cycles (IQR 3) after the first ocrelizumab infusion and 72.5 days (IQR 75.5) after the last one. Most patients presented with late-onset neutropenia (88.9%) and had grade four neutropenia (88.9%). 73% were symptomatic and 63% required inpatient care. No deaths were reported. 89.2% of patients received treatment with granulocyte-colony stimulating factors (G-CSF), antimicrobials or both. All neutropenia events resolved in a median of 4.5 days (IQR 5). G-CSF decreased the recovery time (p < 0.001). Treatment was maintained in 72.4% (follow-up of 1-24 months). Recurrence occurred in the same ocrelizumab cycle (N = 4), in following cycles (N = 4) and after switching to ozanimod (N = 1). No clinical, demographic or treatment features influenced recurrence.

CONCLUSION

Neutropenia occurred early in treatment. Most patients presented with high-grade neutropenia but experienced a mild clinical course. Ocrelizumab resumption was possible. Recurrence may happen in the same or following cycles.