A Case of Late-Onset Neutropenia in Relapsing-Remitting Multiple Sclerosis Following Ocrelizumab Therapy.

Ocrelizumab, a monoclonal antibody, has proven effective in treating both primary progressive and relapsing-remitting multiple sclerosis. Common adverse effects observed in clinical studies include flushing, sore throat, pruritus, and rash. This abstract discusses a case of severe, late-onset neutropenia in a patient with relapsing-remitting multiple sclerosis undergoing ocrelizumab treatment. The neutropenia emerged 46 days following the patient's most recent ocrelizumab dose. The patient responded well to treatment with intravenous meropenem and filgrastim. This rare and unforeseen adverse effect highlights the importance of regular blood monitoring for early detection of severe neutropenia in patients treated with ocrelizumab.