Ocrelizumab, a CD20 monoclonal antibody, is labeled for primary progressive multiple sclerosis (PPMS) and highly active relapsing remitting multiple sclerosis (RRMS) patients who had a prior disease modifying therapy (DMT) history in Turkey. Here we present our 3-year-experience with ocrelizumab.

Patients under ocrelizumab from December 2017 – October 2020 were included in the study. Demographic data, disease history, prognosis and adverse events under ocrelizumab were analyzed.

320 patients were included in the study. Female to male ratio was 1.3:1. Mean age was 45.8. Mean disease duration was 12 years. Mean follow-up period of patients under ocrelizumab treatment is 17 months. 40% of the patients had PPMS- (not active with progression) , 35% had RRMS, 25% had (secondary) progressive MS active with progression. Median EDSS of the patients was 4.48 (min 0 – max 7.5). This was 4.7 for RRMS patients and 4.8 for PPMS patients. Among RRMS patients 30% switched from fingolimod and 29% switched from first line treatments.  9.5% had already been under rituximab another B-cell depleting agent. 2.5% of patients had mild infusion reactions. 10% were positive with Hepatitis-B(HBV) core antigen therefore entecavir prophylaxis was initiated and 1.5% used isoniazid for tuberculosis(TB) prophylaxis.  No HBV or TB reactivation or serious urinary infections`s occurred so far. Available serum IgG and IgM levels were within normal range. 5 patients had to switch to another treatment; 3 because of ineffectiveness, 1 because of a detected breast mass, 1 because of pregnancy. 11 patients had COVID-19 infection, only one needed hospital admission because of respiratory symptoms.

Low drop-out numbers and efficacy of ocrelizumab is compatible with the literature.  We closely monitor patients for possible infectious side effects, our cohort showed no serious adverse events including COVID-19 infection.