Temporal Relationship Between Serum Neurofilament Light Chain and Radiologic Disease Activity in Patients With Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Serum neurofilament light chain (sNfL) levels correlate with multiple sclerosis (MS) disease activity, but the dynamics of this correlation are unknown. We evaluated the relationship between sNfL levels and radiologic MS disease activity through monthly assessments during the 24-week natalizumab treatment interruption period in RESTORE (NCT01071083). METHODS: In the RESTORE trial, participants with relapsing forms of MS who had received natalizumab for ≥12 months were randomized to either continue or stop natalizumab and followed with MRI and blood draws every 4 weeks to week 28 and again at week 52 The sNfL was measured, and its dynamics were correlated with the development of gadolinium-enhancing (Gd+) lesions. Log-linear trend in sNfL levels were modeled longitudinally using generalized estimating equations with robust variance estimator from baseline to week 28. RESULTS: Of 175 patients enrolled in RESTORE, 166 had serum samples for analysis. Participants with Gd+ lesions were younger (37.7 vs 43.1, p = 0.001) and had lower Expanded Disability Status Scale scores at baseline (2.7 vs 3.4, p = 0.017) than participants without Gd+ lesions. sNfL levels increased in participants with Gd+ lesions (n = 65) compared with those without (n = 101, mean change from baseline to maximum sNfL value, 12.1 vs 3.2 pg/mL, respectively; p = 0.003). As the number of Gd+ lesions increased, peak median sNfL change also increased by 1.4, 3.0, 4.3, and 19.6 pg/mL in the Gd+ lesion groups of 1 (n = 12), 2-3 (n = 18), 4-9 (n = 21), and ≥10 (n = 14) lesions, respectively. However, 46 of 65 (71%) participants with Gd+ lesions did not increase above the 95th percentile threshold of the group without Gd+ lesions. The initial increase of sNfL typically trailed the first observation of Gd+ lesions, and the peak increase in sNfL was a median [interquartile range] of 8 [0, 12] weeks after the first appearance of the Gd+ lesion. DISCUSSION: Although sNfL correlated with the presence of Gd+ lesions, most participants with Gd+ lesions did not have elevations in sNfL levels. These observations have implications for the use and interpretation of sNfL as a biomarker for monitoring MS disease activity in controlled trials and clinical practice.

A review of Bruton's tyrosine kinase inhibitors in multiple sclerosis.

Bruton's tyrosine kinase (BTK) inhibitors are an emerging class of therapeutics in multiple sclerosis (MS). BTK is expressed in B-cells and myeloid cells, key progenitors of which include dendritic cells, microglia and macrophages, integral effectors of MS pathogenesis, along with mast cells, establishing the relevance of BTK inhibitors to diverse autoimmune conditions. First-generation BTK inhibitors are currently utilized in the treatment of B-cell malignancies and show efficacy in B-cell modulation. B-cell depleting therapies have shown success as disease-modifying treatments (DMTs) in MS, highlighting the potential of BTK inhibitors for this indication; however, first-generation BTK inhibitors exhibit a challenging safety profile that is unsuitable for chronic use, as required for MS DMTs. A second generation of highly selective BTK inhibitors has shown efficacy in modulating MS-relevant mechanisms of pathogenesis in preclinical as well as clinical studies. Six of these BTK inhibitors are undergoing clinical development for MS, three of which are also under investigation for chronic spontaneous urticaria (CSU), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Phase II trials of selected BTK inhibitors for MS showed reductions in new gadolinium-enhancing lesions on magnetic resonance imaging scans; however, the safety profile is yet to be ascertained in chronic use. Understanding of the safety profile is developing by combining safety insights from the ongoing phase II and III trials of second-generation BTK inhibitors for MS, CSU, RA and SLE. This narrative review investigates the potential of BTK inhibitors as an MS DMT, the improved selectivity of second-generation inhibitors, comparative safety insights established thus far through clinical development programmes and proposed implications in female reproductive health and in long-term administration.

A review of Bruton's tyrosine kinase inhibitors in multiple sclerosis Why was this study done? This study was done to find out about current knowledge on a type of drug, called Bruton's tyrosine kinase inhibitors, or BTK inhibitors. There are currently six BTK inhibitors being studied as a possible new drug for treating multiple sclerosis (MS). Some of these six drugs are also being studied as a possible new drug for chronic spontaneous urticaria, rheumatoid arthritis and systemic lupus erythematosus. These are all autoimmune conditions, where the immune system mistakenly attacks parts of the body. Clinician scientists wanted to understand what is currently known about BTK inhibitors, how they work in the laboratory and how safe they could be for treating autoimmune conditions. This could help us understand more about BTK inhibitors in MS.What did the scientists do? The scientists assessed existing research on these six BTK inhibitors, through a process known as a literature review. These were results from ongoing clinical trials, and information collected through studying BTK inhibitors in laboratories. The researchers pieced together all these findings, to produce this paper that summarizes the results.What did the scientists find? The scientists found that most studies of BTK inhibitors for MS are still ongoing. So far, BTK inhibitors seem to show reasonable safety in most studies, but it is too early to know. The researchers also found out about how BTK inhibitors work in the lab, about what could happen if the drugs are taken for a long time and how they could impact female reproductive health.What do these findings mean? These findings will help other scientists learn more about BTK inhibitors in MS. Trials with BTK inhibitors for MS are still ongoing, but piecing together all the current findings gives a picture of what we know and what still needs to be done.

Immunomodulatory potential of anti-IFN-beta antibodies on monocyte-derived macrophages.

Introduction: Multiple sclerosis (MS) is a disabling neurological disease with an unknown etiology, where the recombinant interferon beta (rIFNß) is the most established treatment. However, the development of anti-IFNß antibodies has posed a significant therapeutic drawback. In this study, the interaction between anti-IFNß antibodies and macrophages was investigated to assess the effects on the immune system. Methodology: Using magnetic beads, anti-IFNß antibodies were extracted from MS patients' sera positive for anti-IFNß antibodies. A negative control (antibody-negative situation) and a baseline control were obtained in parallel. Bead or extracted beadantibody complexes were then incubated vitro with monocyte-derived human macrophages. After incubation, macrophage cultures were tested for 91 immunologically relevant gene expressions by RT-PCR. Results and Discussions: A Gene expression difference between antibody positive and negative situations was hypothesized to reflect the direct effects between antibodies and macrophages. Thus, 37-39 genes were either up-regulated or downregulated due to this direct interaction. Of these, only 2-4 genes were up-regulated, and the rest were down-regulated. These observations suggest that anti-IFNß antibodies have an overall suppressive effect on immunologically relevant gene activity when antibodies interact with macrophages. Conclusion: The fate and effects of circulating anti-IFNß antibodies are mainly unknown. With the observations obtained at in vitro level, such effects, especially from an immunological point of view, are suppressive on immunocompetent cells such as macrophages. However, in vivo verification is necessary.

Fatigue, depression, and product tolerability during long-term treatment with intravenous immunoglobulin (Gamunex® 10%) in patients with chronic inflammatory demyelinating polyneuropathy.

INTRODUCTION/AIMS: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is characterized by progressive weakness and sensory loss, often affecting patient's ability to walk and perform activities of daily living independently. Furthermore, patients often report fatigue and depression which can affect their quality of life. These symptoms were assessed in CIDP patients receiving long-term intravenous immunoglobulin (IVIG) treatment. METHODS: GAMEDIS was a multi-center, prospective, non-interventional study in adult CIDP patients treated with IVIG (10%) and followed for two years. Inflammatory Neuropathy Cause and Treatment (INCAT) disability score, Hughes Disability Scale (HDS), Fatigue Severity Scale (FSS), Beck Depression Inventory II (BDI), Short Form-36 health survey (SF-36) and Work Productivity and Activity Impairment Score Attributable to General Health (WPAI-GH) were assessed at baseline and quarterly. Dosing and treatment intervals, changes in outcome parameters, and adverse events (AEs) were analyzed. RESULTS: 148 evaluable patients were followed for a mean of 83.3 weeks. The mean maintenance IVIG dose was 0.9 g/kg/cycle (mean cycle interval 38 days). Disability and fatigue remained stable throughout the study. Mean INCAT score: 2.4 ± 1.8 at baseline and 2.5 ± 1.9 at study end. HDS: 74.3% healthy/minor symptoms at baseline and 71.6% at study end. Mean FSS: 4.2 ± 1.6 at baseline and 4.1 ± 1.7 at study end. All patients reported minimal/no depression at baseline and throughout. SF-36 and WPAI-GH scores remained stable. Fifteen patients (9.5%) experienced potentially treatment-related AEs. There were no AEs in 99.3% of infusions. DISCUSSION: Long-term treatment of CIDP patients with IVIG 10% in real-world conditions maintained clinical stability on fatigue and depression over 96 weeks. This treatment was well-tolerated and safe.

Serum Neurofilament Light Trajectories and Their Relation to Subclinical Radiological Disease Activity in Relapsing Multiple Sclerosis Patients in the APLIOS Trial.

INTRODUCTION: Several studies have described prognostic value of serum neurofilament light chain (sNfL) at the group level in relapsing multiple sclerosis (RMS) patients. Here, we aimed to explore the temporal association between sNfL and development of subclinical disease activity as assessed by magnetic resonance imaging (MRI) at the group level and evaluate the potential of sNfL as a biomarker for capturing subclinical disease activity in individual RMS patients. METHODS: In the 12-week APLIOS study, patients (N = 284) received subcutaneous ofatumumab 20 mg. Frequent sNfL sampling (14 time points over 12 weeks) and monthly MRI scans enabled key analyses including assessment of the group-level temporal relationship of sNfL levels with on-study subclinical development of gadolinium-enhancing (Gd +)T1 lesions. Prognostic value of baseline sNfL ("high" vs. "low") level for subsequent on-study clinical relapse or Gd + T1 activity was assessed. Individual patient-level development of on-study Gd + T1 lesions was compared across three predictors: baseline Gd + T1 lesion number, baseline sNfL ("high" vs. "low"), and time-matched sNfL. RESULTS: In patients developing Gd + T1 lesions at week 4 (absent at baseline), sNfL levels increased during the month preceding the week-4 MRI scan and then gradually decreased back to baseline. High versus low baseline sNfL conferred increased risk of subsequent on-study clinical relapse or Gd + T1 activity (HR, 2.81; p < 0.0001) in the overall population and, notably, also in the patients without baseline Gd + T1 lesions (HR, 2.48; p = 0.0213). Individual patient trajectories revealed a marked difference in Gd + T1 lesions between patients with the ten highest vs. lowest baseline sNfL levels (119 vs. 19 lesions). Prognostic value of baseline or time-matched sNfL for on-study Gd + T1 lesions was comparable to that of the number of baseline MRI Gd + T1 lesions. CONCLUSIONS: sNfL measurement may have utility in capturing and monitoring subclinical disease activity in RMS patients. sNfL assessments could complement regular MRI scans and may provide an alternative when MRI assessment is not feasible. CLINICALTRIALS: GOV: NCT03560739. CLASSIFICATION OF EVIDENCE: This study provides class I evidence that serum neurofilament light may be used as a biomarker for monitoring subclinical disease activity in relapsing multiple sclerosis patients, as shown by its elevation in the weeks preceding the development of new gadolinium-enhancing T1 lesion activity.

Population Pharmacokinetic-B Cell Modeling for Ofatumumab in Patients with Relapsing Multiple Sclerosis.

BACKGROUND: Ofatumumab, a fully human anti-CD20 monoclonal antibody indicated for the treatment of relapsing forms of multiple sclerosis (RMS), binds to a unique conformational epitope, thereby depleting B cells very efficiently and allowing subcutaneous administration at lower doses. OBJECTIVES: The aims were to characterize the relationship between ofatumumab concentration and B cell levels, including the effect of covariates such as body weight, age, or baseline B cell count, and use simulations to confirm the chosen therapeutic dose. METHODS: Graphical and regression analyses previously performed based on data from a dose-range finding study provided the B cell depletion target used in the present work. All available adult phase 2/3 data for ofatumumab in RMS patients were pooled to develop a population pharmacokinetics (PK)-B cell count model, using nonlinear mixed-effects modeling. The population PK-B cell model was used to simulate B cell depletion and repletion times and the effect of covariates on PK and B cell metrics, as well as the dose response across a range of subcutaneous ofatumumab monthly doses. RESULTS: The final PK-B cell model was developed using data from 1486 patients. The predetermined B cell target was best achieved and sustained with the 20-mg dose regimen, with median B cell count reaching 8 cells/µL in 11 days and negligible repletion between doses. Only weight had a significant effect on PK, which did not translate into any clinically relevant effect on B cell levels. CONCLUSION: The PK-B cell modeling confirms the dose chosen for the licensed ofatumumab regimen and demonstrates no requirement for dose adjustment based on adult patient characteristics.

Safety experience with continued exposure to ofatumumab in patients with relapsing forms of multiple sclerosis for up to 3.5 years.

BACKGROUND: Ofatumumab is approved for the treatment of relapsing multiple sclerosis (RMS). Ongoing safety reporting is crucial to understand its long-term benefit-risk profile. OBJECTIVE: Report the safety and tolerability of ofatumumab in RMS after extended treatment up to 3.5 years. METHODS: Patients completing ASCLEPIOS I/II (phase 3), APLIOS, or APOLITOS (phase 2) trials could enter ALITHIOS, a phase 3b, open-label, long-term safety study. We analyzed cumulative data of continuous ofatumumab treatment and of patients newly switched from teriflunomide. RESULTS: The safety population had 1969 patients: 1292 continuously treated with ofatumumab (median time-at-risk 35.5 months, 3253 patient-years) and 677 newly switched (median time-at-risk 18.3 months, 986 patient-years). A total of 1650 patients (83.8%) had ⩾1 adverse events and 191 (9.7%) had ⩾1 serious adverse events. No opportunistic infections or progressive multifocal leukoencephalopathy events were identified; the risk of malignancies was low. Mean serum immunoglobulin (Ig) G levels remained stable. Mean IgM levels decreased but remained above the lower limit of normal in most. Serious infection incidence was low; decreased Ig levels were not associated with serious infections. CONCLUSION: In patients with up to 3.5 years' exposure, ofatumumab was well tolerated, with no new safety risks identified. These findings, with its established effectiveness, support a favorable benefit-risk profile of ofatumumab in RMS.

How patients with multiple sclerosis acquire disability.

Patients with multiple sclerosis acquire disability either through relapse-associated worsening (RAW) or progression independent of relapse activity (PIRA). This study addresses the relative contribution of relapses to disability worsening over the course of the disease, how early progression begins and the extent to which multiple sclerosis therapies delay disability accumulation. Using the Novartis-Oxford multiple sclerosis (NO.MS) data pool spanning all multiple sclerosis phenotypes and paediatric multiple sclerosis, we evaluated ∼200 000 Expanded Disability Status Scale (EDSS) transitions from >27 000 patients with ≤15 years follow-up. We analysed three datasets: (i) A full analysis dataset containing all observational and randomized controlled clinical trials in which disability and relapses were assessed (n = 27 328); (ii) all phase 3 clinical trials (n = 8346); and (iii) all placebo-controlled phase 3 clinical trials (n = 4970). We determined the relative importance of RAW and PIRA, investigated the role of relapses on all-cause disability worsening using Andersen-Gill models and observed the impact of the mechanism of worsening and disease-modifying therapies on the time to reach milestone disability levels using time continuous Markov models. PIRA started early in the disease process, occurred in all phenotypes and became the principal driver of disability accumulation in the progressive phase of the disease. Relapses significantly increased the hazard of all-cause disability worsening events; following a year in which relapses occurred (versus a year without relapses), the hazard increased by 31-48% (all P < 0.001). Pre-existing disability and older age were the principal risk factors for incomplete relapse recovery. For placebo-treated patients with minimal disability (EDSS 1), it took 8.95 years until increased limitation in walking ability (EDSS 4) and 18.48 years to require walking assistance (EDSS 6). Treating patients with disease-modifying therapies delayed these times significantly by 3.51 years (95% confidence limit: 3.19, 3.96) and 3.09 years (2.60, 3.72), respectively. In patients with relapsing-remitting multiple sclerosis, those who worsened exclusively due to RAW events took a similar length of time to reach milestone EDSS values compared with those with PIRA events; the fastest transitions were observed in patients with PIRA and superimposed relapses. Our data confirm that relapses contribute to the accumulation of disability, primarily early in multiple sclerosis. PIRA begins in relapsing-remitting multiple sclerosis and becomes the dominant driver of disability accumulation as the disease evolves. Pre-existing disability and older age are the principal risk factors for further disability accumulation. The use of disease-modifying therapies delays disability accrual by years, with the potential to gain time being highest in the earliest stages of multiple sclerosis.

Effect of ofatumumab versus placebo in relapsing multiple sclerosis patients from Japan and Russia: Phase 2 APOLITOS study.

BACKGROUND: Ofatumumab, the first fully human anti-CD20 monoclonal antibody, has been developed as a treatment for relapsing multiple sclerosis (RMS) which can be self-administered at home. OBJECTIVE: To investigate the efficacy and safety of ofatumumab in RMS patients from Japan and Russia. METHODS: APOLITOS included a 24-week, double-blind, placebo-controlled core-part followed by an open-label extension-part. Patients were randomized (2:1) to subcutaneous ofatumumab 20 mg or placebo. Primary outcome was the number of gadolinium-enhancing (Gd+) T1 lesions per scan over 24 weeks. RESULTS: Sixty-four patients were randomized (ofatumumab, n = 43; placebo, n = 21). Primary endpoint was met; ofatumumab reduced Gd + T1 lesions versus placebo by 93.6% (p < 0.001) and the results were consistent across regions (Japan/Russia). Ofatumumab reduced annualized T2 lesion and relapse rate versus placebo by week 24. Both groups showed benefit from ofatumumab in the extension-part. Incidence of adverse events was lower with ofatumumab versus placebo (69.8% vs 81.0%); injection-related reactions were most common. No deaths, opportunistic infections, or malignancies were reported. CONCLUSION: Ofatumumab demonstrated superior efficacy versus placebo, with sustained effect through 48 weeks in RMS patients from Japan/Russia. Switching to ofatumumab after 24 weeks led to rapid radiological and clinical benefits. Safety findings were consistent with pivotal trials.

Effect of ofatumumab on pregnancy, parturition, and lactation in cynomolgus monkeys.

Knowledge of the impacts of the anti-CD20 monoclonal antibody ofatumumab on the developing immune system is limited. This study examined the effects of intravenous ofatumumab on pregnancy, parturition, and lactation, and on pre- and postnatal survival and development in cynomolgus monkeys, an established model for developmental toxicity assessment. Pregnant cynomolgus monkeys (n = 42) were randomized to receive vehicle only (control group; n = 14), low-dose ofatumumab (n = 14), or high-dose ofatumumab (n = 14). Survival, clinical outcomes, and clinical pathology investigations were evaluated regularly until lactation day (maternal animals) and postnatal day 180±1 (infants). Anatomic pathology was investigated in euthanized infants and unscheduled terminations of maternal animals and infants. Ofatumumab treatment was not associated with maternal toxicity or embryotoxicity and had no effect on the growth and development of offspring. As expected, B-cell depletion occurred in maternal animals and their offspring, with a reduced humoral immune response in infants of mothers on high-dose ofatumumab. Both effects were reversible. In the high-dose group, perinatal deaths of 3 infants were attributed to infections, potentially secondary to pharmacologically induced immunosuppression. The no-observed adverse-effect level for initial/maintenance ofatumumab doses was 100/20 mg, and 10/3 mg/kg for pharmacological effects in infant animals, which are associated with exposures significantly higher than those following therapeutic doses in humans. In this study with cynomolgus monkeys, ofatumumab treatment was not associated with maternal toxicity or embryotoxicity and had no effect on the growth and development of offspring.

Corneal confocal microscopy differentiates inflammatory from diabetic neuropathy.

BACKGROUND: Immune-mediated neuropathies, such as chronic inflammatory demyelinating polyneuropathy (CIDP) are treatable neuropathies. Among individuals with diabetic neuropathy, it remains a challenge to identify those individuals who develop CIDP. Corneal confocal microscopy (CCM) has been shown to detect corneal nerve fiber loss and cellular infiltrates in the sub-basal layer of the cornea. The objective of the study was to determine whether CCM can distinguish diabetic neuropathy from CIDP and whether CCM can detect CIDP in persons with coexisting diabetes. METHODS: In this multicenter, case-control study, participants with CIDP (n = 55) with (n = 10) and without (n = 45) diabetes; participants with diabetes (n = 58) with (n = 28) and without (n = 30) diabetic neuropathy, and healthy controls (n = 58) underwent CCM. Corneal nerve fiber density (CNFD), corneal nerve fiber length (CNFL), corneal nerve branch density (CNBD), and dendritic and non-dendritic cell density, with or without nerve fiber contact were quantified. RESULTS: Dendritic cell density in proximity to corneal nerve fibers was significantly higher in participants with CIDP with and without diabetes compared to participants with diabetic neuropathy and controls. CNFD, CNFL, and CNBD were equally reduced in participants with CIDP, diabetic neuropathy, and CIDP with diabetes. CONCLUSIONS: An increase in dendritic cell density identifies persons with CIDP. CCM may, therefore, be useful to differentiate inflammatory from non-inflammatory diabetic neuropathy.

Temporal profile of serum neurofilament light in multiple sclerosis: Implications for patient monitoring.

OBJECTIVE: To understand how longitudinal serum neurofilament light chain (sNfL) patterns can inform its use as a prognostic biomarker in multiple sclerosis (MS) and evaluate whether sNfL reflects MS disease activity and disease-modifying therapy usage. METHODS: This was a post hoc analysis of longitudinal data and samples from the ADVANCE trial (NCT00906399) of patients with relapsing-remitting MS (RRMS). sNfL was measured every 3 months for 2 years, then every 6 months for 4 years. Regression models explored how sNfL data predicted 4-year values of brain volume, expanded disability status scale score, and T2 lesions. sNfL levels were assessed in those receiving placebo, peginterferon beta-1a, and those with disease activity. RESULTS: Baseline sNfL was a predictor of 4-year brain atrophy and development of new T2 lesions. Clinical (p = 0.02) and magnetic resonance imaging (MRI) (p < 0.01) outcomes improved in those receiving peginterferon beta-1a whose sNfL decreased to <16 pg/mL after 12 months versus those whose sNfL remained ⩾16 pg/mL. Mean sNfL levels decreased in peginterferon beta-1a-treated patients and increased in placebo-treated patients (-9.5% vs. 6.8%; p < 0.01). sNfL was higher and more variable in patients with evidence of active MS. CONCLUSION: These data support sNfL as a prognostic and disease-monitoring biomarker for RRMS.

Association of Serum Neurofilament Light Levels With Long-term Brain Atrophy in Patients With a First Multiple Sclerosis Episode.

Importance: Data are needed on the potential long-term prognostic association of serum neurofilament light in multiple sclerosis (MS). Objective: To evaluate serum neurofilament light as a biomarker associated with long-term disease outcomes in clinically isolated syndrome. Design, Setting, and Participants: This post hoc cohort study used data from the Controlled High-Risk Avonex Multiple Sclerosis Prevention Study, a 36-month, multicenter, placebo-controlled interferon ß-1a randomized clinical trial conducted from April 1996 to March 2000, and its long-term (5- and 10-year) extension study from February 2001 to March 2009. Participants included individuals with a symptomatic initial demyelinating event and brain magnetic resonance imaging (MRI) lesions suggestive of MS. Data were analyzed from April 2017 through 2019. Exposure: The variable of interest was naturally occurring serum neurofilament light concentration. Main Outcomes and Measures: Gadolinium-enhancing (Gd+) lesion number, T2 lesion volume, and brain parenchymal fraction, a measure of brain atrophy were measured at baseline and 5 and 10 years. Multivariate regression models evaluated whether age, sex, and baseline covariates, including serum neurofilament light, brain parenchymal fraction, Expanded Disability Status Scale, Gd+ lesion count, and T2 lesion volume, were associated with brain parenchymal fraction changes over 5 and 10 years. Results: Among 308 included participants (mean [SD] age, 33.2 [7.6] years; 234 [76.0%] women), baseline serum neurofilament light concentrations were associated with Gd+ lesions (Spearman r = 0.41; P < .001) and T2 lesion volume (Spearman r = 0.42; P < .001). Among covariates for brain parenchymal fraction change, serum neurofilament light concentration had the greatest correlation with change in brain parenchymal fraction at 5 years (Spearman r = -0.38; P < .001) and was the only variable associated with brain parenchymal fraction at 10 years (Spearman r = -0.45; P < .001). Participants in the highest vs lowest baseline serum neurofilament light tertiles showed brain parenchymal fraction reduction at 5 years (-1.83% [95% CI, -1.49% to -2.18%] vs -0.95% [95% CI, -0.78% to -1.12%]; P < .001) and 10 years (-3.54% [95% CI, -2.90% to -4.17%] vs -1.90% [95% CI, -1.43% to -2.37%]; P < .001). At 5 years, 6 of 45 participants (13.3%) in the highest neurofilament tertile and 2 of 52 participants (3.8%) in the lowest neurofilament tertile achieved an Expanded Disability Status Scale score of 3.5 or greater. Conclusions and Relevance: This cohort study found that higher baseline serum neurofilament light levels were associated with increased brain atrophy over 5 and 10 years. These findings suggest that serum neurofilament light could be a biomarker associated with disease severity stratification in early MS and may help to guide intervention.

NK cell markers predict the efficacy of IV immunoglobulins in CIDP.

OBJECTIVE: To assess whether IV immunoglobulins (IVIgs) as a first-line treatment for chronic inflammatory demyelinating polyneuropathy (CIDP) have a regulative effect on natural killer (NK) cells that is related to clinical responsiveness to IVIg. METHODS: In a prospective longitudinal study, we collected blood samples of 29 patients with CIDP before and after initiation of IVIg treatment for up to 6 months. We used semiquantitative PCR and flow cytometry in the peripheral blood to analyze the effects of IVIg on the NK cells. The results were correlated with clinical aspects encompassing responsiveness. RESULTS: We found a reduction in the expression of several typical NK cell genes 1 day after IVIg administration. Flow cytometry furthermore revealed a reduced cytotoxic CD56dim NK cell population, whereas regulatory CD56bright NK cells remained mostly unaffected or were even increased after IVIg treatment. Surprisingly, the observed effects on NK cells almost exclusively occurred in IVIg-responsive patients with CIDP. CONCLUSIONS: The correlation between the altered NK cell population and treatment efficiency suggests a crucial role for NK cells in the still speculative mode of action of IVIg treatment. Analyzing NK cell subsets after 24 hours of treatment initiation appeared as a predictive marker for IVIg responsiveness. Further studies are warranted investigating the potential of NK cell status as a routine parameter in patients with CIDP before IVIg therapy. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that NK cell markers predict clinical response to IVIg in patients with CIDP.

Harnessing Real-World Data to Inform Decision-Making: Multiple Sclerosis Partners Advancing Technology and Health Solutions (MS PATHS).

Background: Multiple Sclerosis Partners Advancing Technology and Health Solutions (MS PATHS) is the first example of a learning health system in multiple sclerosis (MS). This paper describes the initial implementation of MS PATHS and initial patient characteristics. Methods: MS PATHS is an ongoing initiative conducted in 10 healthcare institutions in three countries, each contributing standardized information acquired during routine care. Institutional participation required the following: active MS patient census of ≥500, at least one Siemens 3T magnetic resonance imaging scanner, and willingness to standardize patient assessments, share standardized data for research, and offer universal enrolment to capture a representative sample. The eligible participants have diagnosis of MS, including clinically isolated syndrome, and consent for sharing pseudonymized data for research. MS PATHS incorporates a self-administered patient assessment tool, the Multiple Sclerosis Performance Test, to collect a structured history, patient-reported outcomes, and quantitative testing of cognition, vision, dexterity, and walking speed. Brain magnetic resonance imaging is acquired using standardized acquisition sequences on Siemens 3T scanners. Quantitative measures of brain volume and lesion load are obtained. Using a separate consent, the patients contribute DNA, RNA, and serum for future research. The clinicians retain complete autonomy in using MS PATHS data in patient care. A shared governance model ensures transparent data and sample access for research. Results: As of August 5, 2019, MS PATHS enrolment included participants (n = 16,568) with broad ranges of disease subtypes, duration, and severity. Overall, 14,643 (88.4%) participants contributed data at one or more time points. The average patient contributed 15.6 person-months of follow-up (95% CI: 15.5-15.8); overall, 166,158 person-months of follow-up have been accumulated. Those with relapsing-remitting MS demonstrated more demographic heterogeneity than the participants in six randomized phase 3 MS treatment trials. Across sites, a significant variation was observed in the follow-up frequency and the patterns of disease-modifying therapy use. Conclusions: Through digital health technology, it is feasible to collect standardized, quantitative, and interpretable data from each patient in busy MS practices, facilitating the merger of research and patient care. This approach holds promise for data-driven clinical decisions and accelerated systematic learning.

Corneal Confocal Microscopy Demonstrates Corneal Nerve Loss in Patients With Trigeminal Neuralgia.

Background: The diagnosis of trigeminal neuralgia (TN) is challenging due to the lack of objective diagnostics. Corneal confocal microscopy (CCM) is a non-invasive ophthalmic imaging technique, which allows quantification of corneal nerve fibers arising from the trigeminal ganglion and may allow the assessment of neurodegeneration in TN. Methods: CCM was undertaken in 11 patients with TN and 11 age-matched healthy controls. Corneal nerve fiber density (CNFD), corneal nerve branch density, corneal nerve fiber length (CNFL), corneal nerve fiber width, corneal nerve fiber area, and dendritic cell and non-dendritic cell density with or without nerve fiber contact were quantified. Results: Patients with TN had significantly lower CNFD and CNFL but no difference for any other corneal nerve or dendritic cell parameter in the ipsilateral and the contralateral cornea compared to the control group. There was no significant difference in corneal nerve and cell parameters between patients with TN with and without involvement of the ophthalmic nerve (V1) or with nerve vessel conflict. Conclusion: Corneal confocal microscopy is a rapid non-invasive imaging technique that identifies symmetrical corneal nerve loss in patients with TN.

Blood neurofilament light levels segregate treatment effects in multiple sclerosis.

OBJECTIVE: To determine factors (including the role of specific disease modulatory treatments [DMTs]) associated with (1) baseline, (2) on-treatment, and (3) change (from treatment start to on-treatment assessment) in plasma neurofilament light chain (pNfL) concentrations in relapsing-remitting multiple sclerosis (RRMS). METHODS: Data including blood samples analyses and long-term clinical follow-up information for 1,261 Swedish patients with RRMS starting novel DMTs were analyzed using linear regressions to model pNfL and changes in pNfL concentrations as a function of clinical variables and DMTs (alemtuzumab, dimethyl fumarate, fingolimod, natalizumab, rituximab, and teriflunomide). RESULTS: The baseline pNfL concentration was positively associated with relapse rate, Expanded Disability Status Scale score, Age-Related MS Severity Score, and MS Impact Score (MSIS-29), and negatively associated with Symbol Digit Modalities Test performance and the number of previously used DMTs. All analyses, which used inverse propensity score weighting to correct for differences in baseline factors at DMT start, highlighted that both the reduction in pNfL concentration from baseline to on-treatment measurement and the on-treatment pNfL level differed across DMTs. Patients starting alemtuzumab displayed the highest reduction in pNfL concentration and lowest on-treatment pNfL concentrations, while those starting teriflunomide had the smallest decrease and highest on-treatment levels, but also starting from lower values. Both on-treatment pNfL and decrease in pNfL concentrations were highly dependent on baseline concentrations. CONCLUSION: Choice of DMT in RRMS is significantly associated with degree of reduction in pNfL, which supports a role for pNfL as a drug response marker.

A proof-of-concept application of a novel scoring approach for personalized medicine in multiple sclerosis.

BACKGROUND: Stratified medicine methodologies based on subgroup analyses are often insufficiently powered. More powerful personalized medicine approaches are based on continuous scores. OBJECTIVE: We deployed a patient-specific continuous score predicting treatment response in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: Data from two independent randomized controlled trials (RCTs) were used to build and validate an individual treatment response (ITR) score, regressing annualized relapse rates (ARRs) on a set of baseline predictors. RESULTS: The ITR score for the combined treatment groups versus placebo detected differential clinical response in both RCTs. High responders in one RCT had a cross-validated ARR ratio of 0.29 (95% confidence interval (CI) = 0.13-0.55) versus 0.62 (95% CI = 0.47-0.83) for all other responders (heterogeneity p = 0.038) and were validated in the other RCT, with the corresponding ARR ratios of 0.31 (95% CI = 0.18-0.56) and 0.61 (95% CI = 0.47-0.79; heterogeneity p = 0.036). The strongest treatment effect modifiers were the Short Form-36 Physical Component Summary, age, Visual Function Test 2.5%, prior MS treatment and Expanded Disability Status Scale. CONCLUSION: Our modelling strategy detects and validates an ITR score and opens up avenues for building treatment response calculators that are also applicable in routine clinical practice.

Predicting disability progression in multiple sclerosis: Insights from advanced statistical modeling.

BACKGROUND: There is an unmet need for precise methods estimating disease prognosis in multiple sclerosis (MS). OBJECTIVE: Using advanced statistical modeling, we assessed the prognostic value of various clinical measures for disability progression. METHODS: Advanced models to assess baseline prognostic factors for disability progression over 2 years were applied to a pooled sample of patients from placebo arms in four different phase III clinical trials. least absolute shrinkage and selection operator (LASSO) and ridge regression, elastic nets, support vector machines, and unconditional and conditional random forests were applied to model time to clinical disability progression confirmed at 24 weeks. Sensitivity analyses for different definitions of a combined endpoint were carried out, and bootstrap was used to assess prediction model performance. RESULTS: A total of 1582 patients were included, of which 434 (27.4%) had disability progression in a combined endpoint over 2 years. Overall model discrimination performance was relatively poor (all C-indices ⩽ 0.65) across all models and across different definitions of progression. CONCLUSION: Inconsistency of prognostic factor importance ranking confirmed the relatively poor prediction ability of baseline factors in modeling disease progression in MS. Our findings underline the importance to explore alternative predictors as well as alternative definitions of commonly used endpoints.

Neurofilament light levels are associated with long-term outcomes in multiple sclerosis.

BACKGROUND: Neurofilament light chain (NfL) is a promising marker of disease activity/treatment response in multiple sclerosis (MS), although its predictive value for long-term clinical outcomes remains unclear. OBJECTIVE: We measured NfL from a phase 3 trial in relapsing-remitting MS and investigated its association with outcomes after 8 and 15 years. METHODS: NfL concentrations were measured by single molecule array assay in cerebrospinal fluid (CSF) from MS patients (n = 235) in a 2-year randomized clinical trial (RCT) of intramuscular interferon ß-1a, and in serum (n = 164) from the extension study. RESULTS: Year 2 CSF and Year 3 serum NfL were associated with brain parenchymal fraction (BPF) change over 8 years (p < 0.0001, r = -0.46; p < 0.05. r = -0.36, respectively) and were predictive of reaching Expanded Disability Status Scale (EDSS) ⩾ 6.0 at Year 8 (odds ratio (OR) (upper vs lower tertile) = 3.4; 95% confidence interval (CI) = 1.2-9.9, p < 0.05; OR = 11.0, 95% CI = 2.0-114.6; p < 0.01, respectively). Serum NfL concentration (Year 4) was predictive of reaching EDSS score ⩾6.0 at 15 years (OR (upper vs lower tertile) = 4.9; 95% CI = 1.4-20.4; p < 0.05). NfL concentrations were complementary to 2-year BPF change in predicting long-term outcomes. CONCLUSION: Serum and CSF NfL concentrations were associated with long-term clinical outcomes in MS patients and are promising biomarkers for disease severity stratification supporting treatment decisions.