Serum biomarkers at disease onset for personalized therapy in multiple sclerosis.

The potential of combining serum neurofilament light chain (sNfL) and glial fibrillary acidic protein (sGFAP) levels to predict disability worsening in multiple sclerosis (MS) remains underexplored. We aimed to investigate whether sNfL and sGFAP values identify distinct subgroups of patients according to the risk of disability worsening and their response to disease-modifying treatments (DMTs). This multicentre study, conducted across thirteen European hospitals, spanned from July 15, 1994, to August 18, 2022, with follow-up until September 26, 2023. We enrolled MS patients who had serum samples collected within 12 months from disease onset and before initiating DMTs. Multivariable regression models were used to estimate the risk of relapse-associated worsening (RAW), progression independent of relapse activity (PIRA), and Expanded Disability Status Scale (EDSS) score of 3. Of the 725 patients included, median age was 34.2 years (IQR, 27.6-42.4), and 509 patients (70.2%) were female. Median follow-up duration was 6.43 years (IQR, 4.65-9.81). Higher sNfL values associated with an elevated risk of RAW (HR of 1.45; 95% CI 1.19-1.76; P < 0.001), PIRA (HR of 1.43; 95% CI 1.13-1.81; P = 0.003), and reaching an EDSS of 3 (HR of 1.55; 95% CI 1.29-1.85; P < 0.001). Moreover, higher sGFAP levels were linked to a higher risk of achieving an EDSS score of 3 (HR of 1.36; 95% CI 1.06-1.74; P = 0.02) and, in patients with low sNfL values, to PIRA (HR of 1.86; 95% CI 1.01-3.45; P = 0.04). We further examined the combined effect of sNfL and sGFAP levels. Patients with low sNfL and sGFAP values (NLGL) exhibited a low risk of all outcomes and served as reference. Untreated patients with high sNfL levels showed a higher risk of RAW, PIRA, and reaching an EDSS of 3. Injectable or oral DMTs reduced the risk of RAW in these patients but failed to mitigate the risk of PIRA and reaching an EDSS of 3. Conversely, high-efficacy DMTs counteracted the heightened risk of these outcomes, except for the risk of PIRA in patients with high sNfL and sGFAP levels. Patients with low sNfL and high sGFAP values (NLGH) showed an increased risk of PIRA and achieving an EDSS of 3, which remained unchanged with either high-efficacy or other DMTs. In conclusion, evaluating sNfL and sGFAP levels at disease onset in MS may identify distinct phenotypes associated with diverse immunological pathways of disability acquisition and therapeutic response.

Progression independent of relapse activity can be predicted by passively acquired tapping speed through a smartphone for 1 month: A prospective study.

BACKGROUND: Tapping speed (TS) correlates with baseline disability scales in people with multiple sclerosis (pwMS). OBJECTIVE: The study aimed to address if progression independent of relapse activity (PIRA) could be predicted by first-month measurement of TS. METHODS: Prospective study including pwMS in one referral MS center. Consecutive patients were included and keys/second (Keys/s) were passively measured each day using an in-house smartphone application for 1 month. Median, mean, and maximum keys/s were obtained. Multivariate logistic regression models (including keys/s, age, sex, and baseline disability scores) were obtained for prediction of a PIRA event after 1 year. RESULTS: Overall, 59 patients were included in the final analysis (64.4% women, median age of 44.5 years). However, 10 patients presented a PIRA event, without differences regarding baseline characteristics between PIRA and no-PIRA groups. PIRA group presented lower median keys/s (2 vs 4 keys/s, p = 0.002) and mean keys/s (2.8 vs 4.6, p = 0.008), while maximum keys/s were similar (p = 0.32). A median ⩽ 3 keys/s was independently associated with PIRA (aOR = 16.8, p = 0.03), as did a mean ⩽ 3.7 keys/s (aOR = 17, p = 0.02). These differences were not detected regarding other variables analyzed. CONCLUSION: Low median or mean keys/s obtained during initial month of assessment were indicative of a PIRA event within the next year.

Establishing Normal Serum Values of Neurofilament Light Chains and Glial Fibrillary Acidic Protein Considering the Effects of Age and Other Demographic Factors in Healthy Adults.

Multiple studies have shown the importance of blood-based biomarkers indicating axonal damage (serum neurofilament light chains [sNfL]) or astroglia activation (serum glial fibrillary acidic protein [sGFAP]) for monitoring different neurological diseases. However, normal values of these variables remain to be clearly defined, partly due to the influence of different demographic factors. We investigated demographic differences in a cohort of healthy volunteers. A cross-sectional study was conducted including 116 healthy controls with ages between 18 and 69 years (67.5% females; n = 79). sNfL and sGFAP concentrations were measured using single-molecule arrays. Age and body mass index affected sNfL values, and age was found to be the most important factor. The normal values changed with age, and we established normal values for individuals younger than 45 years as <10 pg/mL and for controls older than 45 years as <15 pg/mL. We established normal values at <10 pg/mL for individuals younger than 45 years and <15 pg/mL for older individuals. Alternatively, a Z-score of 1.5 was relevant for all controls. sGFAP was only affected by age. Differences in normal values were evident by 55 years. The highest normality limit for sGFAP was 140 pg/mL for controls under 55 years and 280 for older controls. We defined normal levels for sNfL and sGFAP and their corresponding age-associated changes. These data may contribute to the application of such variables in clinical practice.

Passive assessment of tapping speed through smartphone is useful for monitoring multiple sclerosis.

INTRODUCTION: Continuously acquired smartphone keyboard interactions may be useful to monitor progression in multiple sclerosis (MS). We aimed to study the correlation between tapping speed (TS), measured as keys/s, and baseline disability scales in patients with MS. METHODS: Single-center prospective study in patients with MS. We passively assessed TS during first week, measured by an "in house" smartphone application. Reliability was assessed by intraclass correlation coefficient (ICC). Correlations between median and maximum keys/s of first week of assessment and baseline disability measures were explored. RESULTS: One-hundred three patients were included: 62.1 % women, with a median (IQR) age of 47 (40.4-54.8) years-old and an EDSS score of 3.0 (2.0-4.0). Distribution by MS subtypes was: 77.7 % relapsing-remitting MS (RRMS), 17.5 % secondary-progressive MS (SPMS) and 4.9 % primary-progressive MS (PPMS). ICC during first week was 0.714 (p < 0.00001). Both median and maximum keys/s showed a negative correlation with Expanded Disability Status Score, 9-hole peg test and timed 25-foot walk and a positive correlation with Processing Speed Test CogEval® raw and Z-score. Median and maximum keys/s were lower in patients diagnosed with SPMS than in RRMS. Both measures of tapping speed were associated with MS phenotype independently of age. CONCLUSION: TS measured through our application is reliable and correlates with baseline disability scales.

COVID-19 vaccines are not associated with axonal injury in patients with multiple sclerosis.

Objective: To evaluate the safety of COVID-19 vaccines in patients with multiple sclerosis (MS) by assessing their impact on serum neurofilament light chain (sNfL) levels as a marker of neuroaxonal damage. Methods: Single-center observational longitudinal study including patients with MS who consecutively received their initial vaccination against SARS-CoV-2 at Hospital Universitario Ramón y Cajal, following the first national immunization program in Spain. Serum samples were collected at baseline and after receiving the second dose of the vaccine. sNfL levels were quantified using the single molecule array (SIMOA) technique. Adverse events, including clinical or radiological reactivation of the disease, were recorded. Results: Fifty-two patients were included (median age, 39.7 years [range, 22.5-63.3]; 71.2% female). After SARS-CoV-2 vaccination, no increased inflammatory activity, either determined by the presence of relapses and/or new MRI lesions and/or high sNfL levels, was detected. Accordingly, there was no difference between median sNfL levels before and after vaccination (5.39 vs. 5.76 pg/ml, p=0.6). Despite this, when looking at baseline patient characteristics before vaccination, younger age associated with disease activity after vaccination (OR 0.87, 95% CI: 0.77-0.98, p=0.022). Larger studies are needed to validate these results. Conclusion: COVID-19 vaccines did not cause reactivation of disease at a clinical, radiological or molecular level, thus suggesting that they are safe in MS patients.

Effect of alemtuzumab over sNfL and sGFAP levels in multiple sclerosis.

Introduction: Alemtuzumab is a highly effective pulsed immune reconstitution therapy for multiple sclerosis (MS). Aim: To evaluate serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) in patients with relapsing-remitting MS who have been treated with Alemtuzumab over the course of 2 years. Methods: This prospective study involved MS patients treated with Alemtuzumab at a referral MS center. Both sNfL and sGFAP were analyzed at baseline and then again at 6, 12, and 24 months post-treatment using the single molecule array (SiMoA) technique. We also recruited matched healthy controls (HCs) for comparison. Results: The study included 46 patients (with a median age of 34.2 [Interquartile range (IQR), 28.7-42.3] years, 27 of which were women [58%]) and 76 HCs. No differences in demographic characteristics were observed between patients and HC. The median disease duration was 6.22 (IQR, 1.56-10.13) years. The median annualized relapse rate before treatment was 2 (IQR, 1-3). At baseline, sNfL and sGFAP levels were higher in MS patients (median of 18.8 [IQR, 10.7-52.7] pg/ml and 158.9 [IQR, 126.9-255.5] pg/ml, respectively) when compared to HC (6.11 [IQR, 2.03-8.54] pg/ml and 91.0 [72.6-109] pg/ml, respectively) (p<0.001 for both comparisons). The data indicates that 80% of patients had high (≥10 pg/ml) sNfL values at baseline. We observed a significant decrease in sNfL levels at 6 (65%, p = 0.02), 12 (70.8%, p<0.001), and 24 (78.1%, p<0.001) months. sNfL reached similar levels to HC only after 24 months of Alemtuzumab treatment. During the follow-up period, no changes were identified in the sGFAP values. Conclusion: Alemtuzumab leads to the normalization of sNfL values in MS patients after 2 years of treatment, with no apparent effect on sGFAP values.

Establishing the best combination of the kappa free light chain index and oligoclonal bands for an accurate diagnosis of multiple sclerosis.

Introduction: The immunoglobulin kappa free light chain (KFLC) index has been proposed as a potentially suitable alternative to oligoclonal IgG bands (OCGB) for diagnosing multiple sclerosis (MS), offering automation and reduced processing time. However, there is no consensus on the preferred approach or how to combine both techniques. Methods: This prospective cohort study aimed to determine the best utilization of OCGB and KFLC index in patients with a clinically isolated syndrome (CIS) followed for at least two years. OCGB and KFLC were assessed using isoelectric focusing and immunoblotting and turbidimetry, respectively. Sensitivity, specificity, and accuracy for diagnosing MS were calculated for each method. Results: The study included 371 patients, with 260 (70.1 %) being women, and a median age of 34.9 (27.8 - 43.9) years. Using a cut-off value of 6.1, the KFLC index demonstrated a sensitivity and specificity of 86.3% and 93.9%, respectively. The sensitivity of OCGB (95.3%) was higher (p < 0.001 vs. KFLC index) and the specificity (100%) was comparable to that of the KFLC index (p = 0.5). The concordance between the methods was not uniform across all patients, with 97.8% agreement in patients with KFLC index ≥ 6.1 and 56.0 % in patients with KFLC index < 6.1. In patients with a KFLC index < 6.1, OCGB still identified 75.0 % of MS patients due to its higher sensitivity. An algorithm using the KFLC index as a screening tool and OCGB as an alternative for patients with a negative KFLC index result achieved an accuracy of 96.3 %. Discussion: Combining the KFLC index and OCGB can provide an easily reproducible and accurate method for diagnosing MS, with OCGB primarily reserved for patients with a KFLC index < 6.1.

B-lymphocyte-guided retreatment contributes to establish good effectiveness and safety profile in MS patients treated with rituximab.

BACKGROUND: Rituximab is extensively used for multiple sclerosis (MS) treatment. However, the best dosage remains to be established. It has been proposed that retreatment could be guided by B lymphocyte (BL) percentages. OBJECTIVE: To establish the best BL value for retreatment with rituximab in MS and to confirm the safety and efficacy of this approach. METHODS: A prospective study was done with an exploratory cohort and a confirmatory cohort of MS patients treated with rituximab between 2017 and 2021. The first one comprised 10 MS patients with BL assessed every 3 months after rituximab infusion and retreatment done when BL values were ≥0.5%. The confirmatory cohort included 41 MS patients (41.5% women, 87.8% with secondary progressive MS, median age = 46.3 (interquartile range: 41.3-52.1) years, disease duration = 14.1 (9-19.6) years, EDSS score = 5.5 (4.0-6.5)). The confirmatory cohort was treated with rituximab following the pattern established in the exploratory cohort. RESULTS: In the exploratory cohort, ≥0.2% BL was established as the best value for retreatment because in most cases, a substantial increase of BL counts was preceded by initial values of 0.2-0.3%. In the confirmatory cohort, rituximab reduced the annualized relapse rate (ARR 0.56 vs. 0.125, p < 0.001), proportion of patients with appearance of new/enlarged T2 lesions (63.4% vs. 12.2%, p < 0.001), gadolinium-enhancing lesions (39% vs. 0%, p < 0.001), and confirmed disability progression (55% vs. 27.5%, p = 0.037). There were 22 patients (53.7%) who achieved NEDA-3. No patients had severe infections, and 10.7% cases had reduced IgG levels. CONCLUSION: Rituximab treatment guided by BL showed high effectiveness and a good safety profile for MS patients after one year of treatment.