Introduction
Ocrelizumab (OCR) is recognized as a highly effective treatment for multiple sclerosis (MS), with its B cell repopulation profiles suggesting potential use as an immune reconstitution therapy. However, there is limited data on the recurrence of disease activity following the cessation of OCR treatment.
Methods
This study involved a multicenter retrospective cohort of MS patients who had discontinued OCR treatment for at least twelve months, without transitioning to another treatment, after receiving a minimum of one full dosage of 600 mg. Focal inflammation was defined by the occurrence of a clinical relapse or significant MRI activity, specifically the presence of three or more new T2 lesions or two or more contrast-enhancing lesions.
Results
Out of 53 MS patients included in the study, 41 had relapsing remitting MS (RRMS), 5 had secondary progressive MS (SPMS), and 7 had primary progressive MS (PPMS). The median follow-up period post-OCR discontinuation was 16 months. Focal inflammation after discontinuation was observed exclusively in RRMS patients, with 2.4% (1/41) showing significant MRI activity alongside clinical symptoms, and 7.3% (3/41) presenting with a suspected clinical relapse without radiological activity. Overall, 9.8% (4/41) of RRMS patients experienced focal inflammation at a median time of 17 months following their last OCR infusion.
Discussion
The findings indicate that while the recurrence of focal inflammation after OCR discontinuation is low, it is not absent, suggesting that discontinuation may not be suitable for all patients. The study underscores the importance of further, larger studies to explore the potential of OCR as an immune reconstitution therapy in the treatment of MS.
