A retrospective single-center study in multiple sclerosis finds that plasma neurofilament light chain (pNfL) results are strongly correlated between Roche’s Elecsys NfL assay and Fujirebio’s Lumipulse G NfL platform. In 253 participants, the assays showed a Pearson correlation of r=0.879 on the raw scale. The work is aimed at practical interoperability for clinicians and researchers who compare results across sites or over time when labs adopt different analytic systems. Better cross-platform comparability can reduce friction for longitudinal monitoring and trial biomarker use. As pNfL becomes a more common risk and disease-activity marker, standardization and platform mapping remain central to adoption.