Ocrelizumab for multiple sclerosis.

BACKGROUND

Ocrelizumab is a humanised anti-CD20 monoclonal antibody developed for the treatment of multiple sclerosis (MS). It was approved by the Food and Drug Administration (FDA) in March 2017 for using in adults with relapsing-remitting multiple sclerosis (RRMS) and primary progressive multiple sclerosis (PPMS). Ocrelizumab is the only disease-modifying therapy (DMT) approved for PPMS. In November 2017, the European Medicines Agency (EMA) also approved ocrelizumab as the first drug for people with early PPMS. Therefore, it is important to evaluate the benefits, harms, and tolerability of ocrelizumab in people with MS.

OBJECTIVES

To assess the benefits, harms, and tolerability of ocrelizumab in people with RRMS and PPMS.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL, and two trials registers on 8 October 2021. We screened reference lists, contacted experts, and contacted the main authors of studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs) involving adults diagnosed with RRMS or PPMS according to the McDonald criteria, comparing ocrelizumab alone or associated with other medications, at the approved dose of 600 mg every 24 weeks for any duration, versus placebo or any other active drug therapy.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Four RCTs met our selection criteria. The overall population included 2551 participants; 1370 treated with ocrelizumab 600 mg and 1181 controls. Among the controls, 298 participants received placebo and 883 received interferon beta-1a. The treatment duration was 24 weeks in one study, 96 weeks in two studies, and at least 120 weeks in one study. One study was at high risk of allocation concealment and blinding of participants and personnel; all four studies were at high risk of bias for incomplete outcome data. For RRMS, compared with interferon beta-1a, ocrelizumab was associated with: 1. lower relapse rate (risk ratio (RR) 0.61, 95% confidence interval (CI) 0.52 to 0.73; 2 studies, 1656 participants; moderate-certainty evidence); 2. a lower number of participants with disability progression (hazard ratio (HR) 0.60, 95% CI 0.43 to 0.84; 2 studies, 1656 participants; low-certainty evidence); 3. little to no difference in the number of participants with any adverse event (RR 1.00, 95% CI 0.96 to 1.04; 2 studies, 1651 participants; moderate-certainty evidence); 4. little to no difference in the number of participants with any serious adverse event (RR 0.79, 95% CI 0.57 to 1.11; 2 studies, 1651 participants; low-certainty evidence); 5. a lower number of participants experiencing treatment discontinuation caused by adverse events (RR 0.58, 95% CI 0.37 to 0.91; 2 studies, 1651 participants; low-certainty evidence); 6. a lower number of participants with gadolinium-enhancing T1 lesions on magnetic resonance imaging (MRI) (RR 0.27, 95% CI 0.22 to 0.35; 2 studies, 1656 participants; low-certainty evidence); 7. a lower number of participants with new or enlarging T2-hyperintense lesions on MRI (RR 0.63, 95% CI 0.57 to 0.69; 2 studies, 1656 participants; low-certainty evidence) at 96 weeks. For PPMS, compared with placebo, ocrelizumab was associated with: 1. a lower number of participants with disability progression (HR 0.75, 95% CI 0.58 to 0.98; 1 study, 731 participants; low-certainty evidence); 2. a higher number of participants with any adverse events (RR 1.06, 95% CI 1.01 to 1.11; 1 study, 725 participants; moderate-certainty evidence); 3. little to no difference in the number of participants with any serious adverse event (RR 0.92, 95% CI 0.68 to 1.23; 1 study, 725 participants; low-certainty evidence); 4. little to no difference in the number of participants experiencing treatment discontinuation caused by adverse events (RR 1.23, 95% CI 0.55 to 2.75; 1 study, 725 participants; low-certainty evidence) for at least 120 weeks. There were no data for number of participants with gadolinium-enhancing T1 lesions on MRI and number of participants with new or enlarging T2-hyperintense lesions on MRI.

AUTHORS' CONCLUSIONS: For people with RRMS, ocrelizumab probably results in a large reduction in relapse rate and little to no difference in adverse events when compared with interferon beta-1a at 96 weeks (moderate-certainty evidence). Ocrelizumab may result in a large reduction in disability progression, treatment discontinuation caused by adverse events, number of participants with gadolinium-enhancing T1 lesions on MRI, and number of participants with new or enlarging T2-hyperintense lesions on MRI, and may result in little to no difference in serious adverse events (low-certainty evidence). For people with PPMS, ocrelizumab probably results in a higher rate of adverse events when compared with placebo for at least 120 weeks (moderate-certainty evidence). Ocrelizumab may result in a reduction in disability progression and little to no difference in serious adverse events and treatment discontinuation caused by adverse events (low-certainty evidence). Ocrelizumab was well tolerated clinically; the most common adverse events were infusion-related reactions and nasopharyngitis, and urinary tract and upper respiratory tract infections.