An observational comparison of natalizumab vs. fingolimod using JCV serology to determine therapy

Abstract

Background: The lack of prospective trial data comparing certain multiple sclerosis (MS) therapies could be addressed with observational research. Objective: The objective of this paper is to investigate outcomes of natalizumab versus fingolimod treatment in an MS cohort using a novel method of patient selection. Methods: We reviewed entries from our clinic’s database for all relapsing–remitting MS patients started on fingolimod and natalizumab where JCV serology was used to determine treatment. We analyzed each group for time to first relapse and in a second analysis, time to first relapse or gadolinium-enhancing lesion. Results: Sixty-nine patients on natalizumab and 36 on fingolimod met our inclusion criteria and had adequate follow-up for analysis. The baseline clinical characteristics at the time of treatment switch were similar. With a mean follow-up of 1.5 years for both treatment groups, there was a trend favoring natalizumab in time to first relapse, although this was not statistically significant (2.20 (0.87, 5.55) p = 0.095). There was a significant difference in the secondary outcome, time to relapse or gadolinium-enhancing lesion (2.31 (1.03, 5.17) p = 0.041), favoring natalizumab. Adjusted analyses favored natalizumab for both outcomes ( p < 0.05). Conclusion: This work employed an observational study design where treatment allocation by JCV serology allowed for treatment groups with well-balanced characteristics.