Real world application of ocrelizumab in multiple sclerosis: Single-center experience of 128 patients

Background: Pivotal trials showed good clinical efficiency of the monoclonal antibody ocrelizumab while being well tolerated and manageable in multiple sclerosis (MS). However, data on adverse events in everyday practice are scarce. Hence, our study aims at investigating short-term tolerability of ocrelizumab in a "real-world" setting. Methods: In this retrospective cohort study, data of 128 (86 relapsing-remitting, 42 progressive) MS patients at initiation of ocrelizumab were analyzed at the MS center of the University of Erlangen, Germany. Additionally, follow-up data of 68 patients at 6-months retreatment were analyzed. Structured phone interviews were applied after ocrelizumab initiation to report undocumented side effects. Results: Patients predominantly switched from monoclonal antibodies (46%), orals (20%), injectables (10%), steroids or immunosuppressants (each 8%), with a mean interval of 9.0 months after the last application of the previous immunotherapy. Applying a combined premedication with steroids, antihistamines and antipyretics for> 90% of patients, ocrelizumab treatment was well tolerated and mainly comprised mild (n = 59/128 at initiation, n = 5/68 at 6 months retreatment) and rarely moderate (n = 7/128 at initiation, n = 2/68 at 6 months) side effects. Predominantly mild infusion related reactions (IRR) were reported with a declining percentage over the follow-up applications. Infections occurred rarely. No severe side effects were observed. Secondary, treatment appeared efficient when looking at clinical surrogates of stable disease. Discussion: Our study delineates good short-term tolerability of ocrelizumab in a miscellaneous "real-world" MS cohort. Additional studies are warranted to confirm these beneficial findings and to reveal safety concerns in the longer-term follow-up.