Serum neurofilament light chain (sNfL) levels have been proposed as a biomarker of the clinical activity, disability progression, and response to treatment of people with multiple sclerosis (PwMS); however, questions remain about its implementation in clinical practice. Ocrelizumab (OCR) has proven effective in improving clinical and radiological outcomes and reducing sNfL levels. This real-life study followed the sNfL levels of 30 PwMS treated for 12 months with OCR and evaluated the usefulness of this biomarker for their short-term prognosis, considering expanded disability status scale (EDSS), annualized relapse rate (ARR), radiological activity, and NEDA-3 values. OCR reduced ARR in 83% of PwMS and radiological activity in 80%. EDSS was maintained, while NEDA-3 was achieved in 70% at 12 months. OCR produced an early reduction in sNfL levels (at 3 months). At baseline, greater MRI-evaluated radiological activity was associated with higher sNfL levels. sNfL levels over the first 12 months of treatment did not predict a suboptimal response or sustained control of the disease. Longer-term studies are needed to explore the predictive usefulness of sNfL levels in PwMS treated with high-efficacy drugs.

Serum neurofilament light chain (sNfL) levels have been proposed as a biomarker of the clinical activity, disability progression, and response to treatment of people with multiple sclerosis (PwMS); however, questions remain about its implementation in clinical practice. Ocrelizumab (OCR) has proven effective to improve clinical and radiological outcomes and to reduce sNfL levels. This real-life study followed the sNfL levels of 30 PwMS treated for 12 months with OCR and evaluated the usefulness of this biomarker for the short-term prognosis, considering expanded disability status scale (EDSS), annualized relapse rate (ARR), radiological activity, and NEDA-3 values. OCR reduced the ARR in 83% of PwMS and the radiological activity in 80%. Their EDSS was maintained, while NEDA-3 was achieved in 70% at 12 months. OCR produced an early reduction in sNfL levels (at 3 months). At baseline, greater MRI-evaluated radiological activity was associated with higher sNfL levels. sNFL levels over the first 12 months of treatment did not predict a suboptimal response or sustained control of the disease. Longer-term studies are needed to explore the predictive usefulness of sNfL levels in PwMS treated with high-efficacy drugs

Relapsing–remitting multiple sclerosis (RRMS) is characterized by neuroaxonal damage, astrogliosis and inflammation. These mechanisms may already be active from early disease stages, underscoring the need for sensitive biomarkers capable of capturing treatment-related biological effects beyond conventional clinical measures. In this multicenter, ambispective, observational real-world study, the longitudinal effects of ozanimod on serum biomarkers were evaluated, during the first year of treatment in patients with low-to-moderate activity RRMS. Serum neurofilament light chain (sNfL), glial fibrillary acidic protein (sGFAP) and cytokines associated with immune activity (IFN-γ, IL-17, IL-6, IL-10, and IL-1β) were quantified at baseline, 6 months, and 12 months using an ultrasensitive single-molecule array (SIMOA). Ozanimod was associated with significant reductions in sNfLs and sGFAP at 12 months. Concomitantly, significant decreases in IFN-γ and IL-1β were observed. IL-17 levels remained unchanged in the overall cohort but decreased in patients with higher baseline IL-17 levels. These findings demonstrate coordinated modulation of biomarkers reflecting neuroaxonal damage, astroglial activation, and inflammatory activity under ozanimod treatment in early RRMS in real-world conditions. These results highlight the biological relevance of early intervention within a therapeutic window of opportunity and support the potential utility of serum biomarkers for monitoring biological treatment effects in clinical practice.

Dimethyl fumarate (DMF) and diroximel fumarate (DRF) are two treatments used in multiple sclerosis (MS), that have been shown to be effective in controlling MS patients. DRF was intro-duced in 2019, with the aim of decreasing the gastrointestinal side effects caused by DMF. Few real-life studies verify the data provided in the clinical trials. Methods: A retrospective descriptive study was conducted in MS patients at the Hospital Universitario Torrecárdenas under treatment with DRF and DMF. Demographic, clinical, and analytical variables were studied and compared between groups. Results: 60 patients were recruited, 30 with each treatment, observing similar baseline characteristics. Fewer gastrointestinal (GI) effects were observed in the DRF group, while more infections were detected in the DMF group. We recorded lower levels in the DRF group, with 4 moderate-severe lymphopenia in the DRF group vs. none in the DMF group. In addition, we observed a decrease in lymphocytes after the change from DMF to DRF in patients with a change. Conclusions: Our real-life analysis of patients treated with DMF or DRF supports studies’ findings of decreased GI side effects with DRF vs. DMF, without decreasing efficacy. However, our data show greater reduction in lymphocytes in patients with DRF compared to DMF, so more studies are necessary.