Comparison of Simoa TM and Ella TM to assess serum neurofilament‐light chain in multiple sclerosis

We compared Simoa TM and Ella TM 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 TM instrument overestimated values by 17%, but as the data were linear ( p = 0.57), it was possible to apply a correction factor to Ella TM results. As for Simoa TM , serum neurofilament‐light chain levels measured by Ella TM 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.