Comparison of Simoa and Ella to assess serum neurofilament-light chain in multiple sclerosis.

We compared Simoa and Ella immunoassays to assess serum neurofilament-light chain levels in 203 multiple sclerosis patients from the OFSEP HD study. There was a strong correlation (ρ = 0.86, p < 0.0001) between both platforms. The Ella instrument overestimated values by 17%, but as the data were linear (p = 0.57), it was possible to apply a correction factor to Ella results. As for Simoa , serum neurofilament-light chain levels measured by Ella were correlated with age and EDSS and were significantly higher in active multiple sclerosis, suggesting that these assays are equivalent and can be used in routine clinical practice.