Real-world experience with Ocrelizumab in multiple sclerosis patients: Two years follow up in Qatar

Objective: This study evaluates the generalizability of data from Ocrelizumab phase 3 clinical trials and its effectiveness in a real-world setting of an Arab population With in a rapidly developing country such as Qatar. Background: Ocrelizumab was FDA approved in 2017 as the newest drug for the treatment of both relapsing-remitting (RRMS) and primary progressive multiple sclerosis (PPMS). OPERA I/II, the major clinical trials, for RRMS shows it is highly efficacious in controlling clinical and radiological activity with a good safety profile and generalizability. Design/Methods: In this retrospective longitudinal cohort study patients were between 18-75 years old;had a confirmed MS;started Ocrelizumab after physician approval;received minimum 3 infusions and 24 months follow up. Primary outcomes: Clinical relapses, baseline and monitoring imaging and adverse events. Secondary outcomes: Demographics, disability outcomes and prior disease-modifying therapies. Results: Of 83 patients, 65 met inclusion criteria. Mean age was 38.7, 58.5% were male, 31.7% were treatment-naive, 52 had RRMS, 5 had PPMS and 3 had SPMS. Average duration of disease and number of infusions was 7.75 years and 3.2 respectively. Average number of gadolinium-enhancing lesions on baseline MRI was 1.27 and 0.07 after treatment. 11 patients had mild adverse events (infusion-related reactions), 13 had URTIs with 1 patient having COVID pneumonia, and 1 patient had UTI. Two patients developed cancer while on treatment. Compared to OPERA I/II, patients in Qatar were older (mean age of 38.7 vs. 37.1 and 37.2), mostly male (58.5% vs. 65.9% and 65.0%), had similar mean EDSS score (2.57±2.67 vs 2.86±1.24 and 2.78±1.30) but longer duration of disease (7.75±6.72 vs. 6.7±6.4 and 6.7±6.1). Conclusions: Ocrelizumab is highly effective for the treatment of MS, especially in this Arab population with a long follow-up period. Compared to previous clinical trials, patients in Qatar had different demographic characteristics, with longer disease durations and fewer enhancing lesions at baseline.