No evidence of disease activity status over 3 years in a real-world cohort of relapsing remitting MS patients in Germany.

Background: Over the last decade, therapy of relapsing remitting multiple sclerosis (RRMS) has evolved with the approval of several new treatment concepts. Thus, treatment goals have become more ambitious aiming at "no evidence of disease activity" (NEDA). As NEDA-3, this concept comprises freedom of clinical disease progression and relapses as well as inflammatory MRI activity. So far, data on NEDA status mainly stem from post-hoc analyses of drug approval studies. Yet, less is known about the significance of NEDA in "real-world" clinical settings. Hence, our study aims at investigation of NEDA in a heterogeneous cohort of relapsing MS patients.

Methods: This is a retrospective single-center study at the Department of Neurology of the University Hospital Erlangen, Germany, including data of 306 patients with relapsing forms of MS (RMS) or clinical isolated syndrome (CIS) from 2009 to 2016. Inclusion required sufficient clinical information and in house cranial MRI follow-up data sets at baseline and at follow-up after one year with a potential extension to two and three year follow-up, if possible. NEDA-3 status, its correlation to clinical features, associated medication and NEDA failure (EDA) were analyzed.

Results: In a cohort of RMS patients at the early stages of the disease (median EDSS 1.5, mean disease duration 30 months) at baseline, 45% retained NEDA-3 status after one year. This percentage decreased in year two (29%) and three (21%) of follow-up. MRI criteria were responsible for loss of NEDA status in 64% of cases and CIS patients were more likely to sustain NEDA status. Therapy with monoclonal antibodies appeared superior in sustaining NEDA status as compared to injectables or oral treatment options.

Discussion: In our real-world analysis, we confirm the potential of NEDA for the evaluation and surveillance of MS disease activity, progression and therapy efficacy. Despite highly efficient immunomodulatory treatment, NEDA-3 was only preserved in a minority of patients. Monoclonal antibodies may yield best NEDA rates. Further studies are warranted to evaluate the value of the NEDA concept in real-world settings beyond standardized clinical studies.