CASE REPORT article
Front. Neurosci.
Sec. Neuropharmacology
This article is part of the Research TopicInnovation in multiple sclerosis and autoimmune diseases of the central nervous systemView all articles
Late-Onset Severe Neutropenia in Patients with Relapsing Remitting Multiple Sclerosis Treated with Ocrelizumab: Case Report and Literature Review
Provisionally accepted
- 1Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, United States
- 2Neurology, Lenox Hill Hospital, New York, United States
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Objective: To describe two cases of recurrent, delayed-onset severe neutropenia several months following ocrelizumab therapy in patients with relapsing-remitting multiple sclerosis (RRMS). Background: A rare adverse effect of ocrelizumab is neutropenia, with late-onset neutropenia (LON) occurring more rarely. Literature guiding management of transient recurrent neutropenia in the setting of anti-CD20 therapy is lacking. Methods: Case 1: 38-year-old female emergency physician with RRMS developed severe transient spontaneously resolving asymptomatic neutropenia three months after ocrelizumab infusion. Two years later, she developed severe symptomatic LON and required antibiotics and granulocyte colony-stimulating factor (GCSF). Ocrelizumab was held, patient switched to ozanimod, but neutropenia recurred. Due to concerns of MS progression, ocrelizumab was restarted after the patient transitioned to a telehealth setting, with no recurrence of neutropenia at one-year follow-up. Case 2: 35-year-old male emergency physician with RRMS developed severe transient spontaneously resolving asymptomatic neutropenia three months after ocrelizumab infusion. Ocrelizumab was resumed after absolute neutrophil count recovery. Two years later, he developed moderate symptomatic LON during a suspected viral illness. Ocrevus was discontinued at this point. A subsequent episode occurred three months later during confirmed rhinovirus infection, again resolving promptly. Conclusion: These cases highlight the unpredictable nature of recurrent LON with ocrelizumab and suggest the possibility of immune-mediated marrow suppression, potentially unmasked or worsened by infections, rather than direct drug toxicity, highlighting the need for clearer management guidelines.
Keywords: Multiple Sclerosis, Ocrelizumab, Late onset neutropenia, Autoimmune, case report
Received: 13 Aug 2025; Accepted: 31 Oct 2025.
Copyright: © 2025 Tauro, Awada, Malhotra and Harel. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Asaff Harel, aharel@northwell.edu
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.