Risk of requiring a walking aid after 6.5 years of ocrelizumab treatment in patients with relapsing multiple sclerosis: Data from the OPERA I and OPERA II trials

Background and purpose Requiring a walking aid is a fundamental milestone in multiple sclerosis (MS), represented by an Expanded Disability Status Scale (EDSS) score ≥6.0. In the present study, we assess the effect of ocrelizumab (OCR) on time to EDSS score ≥6.0 in relapsing MS. Methods Time to EDSS score ≥6.0 confirmed for ≥24 and ≥48 weeks was assessed over the course of 6.5 years (336 weeks) in the double‐blind period (DBP) and open‐label extension (OLE) period of the OPERA I (NCT01247324) and OPERA II (NCT01412333) studies. Results Time to reach EDSS score ≥6.0 was significantly delayed in those initially randomized to OCR versus interferon. Over 6.5 years, the risk of requiring a walking aid confirmed for ≥24 weeks was 34% lower among those who initiated OCR earlier versus delayed treatment (average hazard ratio [HR] DBP + OLE 0.66, 95% confidence interval [CI] 0.45–0.95; p = 0.024); the risk of requiring a walking aid confirmed for ≥48 weeks was 46% lower (average HR DBP+OLE 0.54, 95% CI 0.35–0.83; p = 0.004). Conclusion The reduced risk of requiring a walking aid in earlier initiators of OCR demonstrates the long‐term implications of earlier highly effective treatment. Data from the OPERA I and OPERA II trials in relapsing multiple sclerosis show that earlier ocrelizumab (OCR) use delays the time to requiring a walking aid (Expanded Disability Status Scale score ≥6.0). Differences in disability progression between OCR–OCR continuers versus interferon–OCR switchers were evident throughout the open‐label extension, indicating that switching to OCR is never as effective as earlier treatment, and does not reverse lost function. These results demonstrate the benefit of early and continuous OCR treatment.