Ocrelizumab, a humanized anti-CD20 monoclonal antibody, has been approved in Europe for the treatment of adult patients with active relapsing multiple sclerosis (RMS) and primary progressive multiple sclerosis (PPMS), on the basis of previous phase III studies. However, limited data were available on ocrelizumab efficacy in RMS according to the Lublin definition of activity (clinical and/or imaging features) used in the current drug label. The PRO-MSACTIVE study was thus designed to provide additional data on ocrelizumab efficacy according to this definition, and also on safety and patient reported outcomes (PROs).

PRO-MSACTIVE is a national, multicenter, open-label, single-arm phase IV French study, conducted in patients with active RMS (relapsing-remitting multiple sclerosis, RRMS, or secondary progressive multiple sclerosis, SPMS). The primary endpoint, which was assessed at week (W) 48, was defined as the proportion of patients free of disease activity (defined by no relapses and no T1 gadolinium-enhancing nor new and/or enlarging T2 lesions using brain MRI). Disease activity, disability and PROs using 6 questionnaires for disease severity, quality of life, impact on work productivity, and treatment satisfaction were described at W24 and W48. Adverse events were described until W72.

Among the 422 analyzed patients (RRMS: 376, SPMS: 46), 63.3% (95% CI [58.5%; 67.9%]) were free of disease activity at W48 (RRMS: 62.2% [57.1%; 67.2%], SPMS: 71.7% [56.5%; 84.0%]). A total of 358 patients (84.8%; RRMS: 84.6%, SPMS: 87.0%) were relapse-free up to W48, and the overall adjusted annualized relapse rate was 0.14 (RRMS: 0.15, SPMS: 0.09). Overall, 67.8% of patients (RRMS: 66.8%, SPMS: 76.1%) had no evidence of MRI activity (no T1 gadolinium-enhancing lesions [83.4%] and no new/enlarging T2 lesions [75.1%]); 58.5% of patients (RRMS: 57.7%, SPMS: 65.2%) achieved No Evidence of Disease Activity (NEDA: no relapses, no confirmed disability progression, and no MRI activity) at W48. All PRO scores were stable between the first dose of ocrelizumab and W48 and better outcomes were seen for patients having an EDSS score ≥4. Overall, 89.3% of patients reported adverse events, 62.3% adverse events assessed as related to ocrelizumab, and 8.5% serious adverse events. No serious infusion-related reactions, opportunistic infections, progressive multifocal leukoencephalopathy, nor deaths were reported. No new safety signal was identified.

These data confirm the efficacy of ocrelizumab in a pragmatic setting and its favorable benefit-risk profile in patients with RMS.

(ClinicalTrials.gov identifier: NCT03589105; EudraCT identifier: 2018-000780-91).