Serum neurofilament light chain levels help predict response to treatment in multiple sclerosis

Low baseline levels of serum neurofilament light chains (sNfL) may help identify multiple sclerosis (MS) patients who are likely to optimally respond to dimethyl fumarate (DMF) treatment, a recent study has found.

Eighty relapsing-remitting MS patients (median age 41.5 years, 61 women) participated in the study. All patients were initiating DMF treatment. Single molecule array was used to measure sNfL levels at baseline and at 3, 6, and 12 months. An additional analysis of blood lymphocyte subsets was carried out using flow cytometry. Disease activity was assessed after a year.

The median sNfL concentration at baseline was 10.1 pg/mL, which decreased throughout treatment. By 3 months, there was a 4.0-pg/mL decrease from baseline, eventually reaching a 6.7-pg/mL difference by 12 months.

By the end of the study, 50 patients (62.5 percent) were classified as having no evidence of disease activity (NEDA), while 30 (37.5 percent) had ongoing disease activity (ODA).

While sNfL levels dropped with ongoing treatment in both NEDA and ODA patients (p<0.0001 for both groups), stabilization happened earlier in the NEDA group, occurring after 3 months of treatment, as opposed to ODA comparators, who needed 12 months of DMF.

NEDA patients also had significantly lower sNfL levels at baseline (median, 8.8 vs 14.5 pg/mL; p=0.0001), which remained consistent at 3 (6.5 vs 10.2 pg/mL; p=0.004) and 6 (6.5 vs 8.3 pg/mL; p=0.03) months.

At a cutoff value of 12.0 pg/mL, receiver operating characteristic curve analysis showed that baseline sNfL could predict response to DMF reasonably well, with an area under the curve of 0.75 (p=0.0002), such that those with levels below the threshold were more likely to achieve NEDA at 1 year.