NEDA-3 achievement in early highly active relapsing remitting multiple sclerosis patients treated with Ocrelizumab or Natalizumab

background: in the early stages of multiple sclerosis (MS), initiating high-efficacy disease-modifying therapy (HE DMTs) may represent an optimal strategy for delaying neurological damage and long-term disease progression, especially in highly active MS patients (HAMS). natalizumab (NAT) and Ocrelizumab (OCR) are recognized as HE DMTs with significant anti-inflammatory effects. this study investigates NEDA-3 achievement in treatment-naïve HAMS patients receiving NAT or OCR over three years. methods: we retrospectively enrolled treatment-naïve HAMS patients undergoing NAT or OCR, collecting demographic, clinical, and instrumental data before and after treatment initiation to compare with propensity score analysis disease activity, time to disability worsening, and NEDA-3 achievement. results: we recruited 281 HAMS patients with a mean age of 32.7 years (SD 10.33), treated with NAT (157) or OCR (124). after three years, the kaplan-meier probability of achieving NEDA-3 was 66.0 % (95 % CI: 57.3 % - 76.0 %) with OCR and 68.2 % (95 % CI: 59.9 % - 77.7 %) with NAT without significant differences between the two groups (p = 0.27) DISCUSSION AND CONCLUSION: starting HE DMT with monoclonal antibodies for HAMS could achieve NEDA-3 in a high percentage of patients without differences between NAT or OCR.