The EDSS-Plus, an improved endpoint for disability progression in secondary progressive multiple sclerosis

Understanding multiple sclerosis as a disease spectrum: above and below the clinical threshold

PURPOSE OF REVIEW

Research in multiple sclerosis (MS) has long been predicated on clinical groupings that do not reflect the underlying biologic heterogeneity apparent within patient populations. This review explicates the various levels of explanation through which the spectrum of disease is described and investigated both above and below the clinical threshold of detection, as framed by the topographical model of MS, to help advance a cogent mechanistic framework.

RECENT FINDINGS

Contemporary evidence has amended the view of MS as consisting of sequential disease phases in favor of a spectrum of disease with an admixture of interdependent and dynamic pathobiological axes driving tissue injury and progression. Recent studies have shown the presence of acute and compartmentalized inflammation and mechanisms of neurodegeneration beginning early and evolving throughout the disease continuum. Still, the gap between the understanding of immunopathologic processes in MS and the tools used to measure relevant molecular, laboratory, radiologic, and clinical metrics needs attention to enable better prognostication of disease and monitoring for changes along specific pathologic axes and variable treatment outcomes.

SUMMARY

Aligning on a consistently-applied mechanistic framework at distinct levels of explanation will enable greater precision across bench and clinical research, and inform discourse on drivers of disability progression and delivery of care for individuals with MS.

Efficacy of intrathecal mesenchymal stem cell-neural progenitor therapy in progressive MS: results from a phase II, randomized, placebo-controlled clinical trial

BACKGROUND

Mesenchymal stem cell-neural progenitors (MSC-NPs) are a bone marrow mesenchymal stem cell (MSC)-derived ex vivo manipulated cell product with therapeutic potential in multiple sclerosis (MS). The objective of this study was to determine efficacy of intrathecal (IT) MSC-NP treatment in patients with progressive MS.

METHODS

The study is a phase II randomized, double-blind, placebo-controlled clinical trial with a compassionate crossover design conducted at a single site. Subjects were stratified according to baseline Expanded Disability Status Scale (EDSS) (3.0-6.5) and disease subtype (secondary or primary progressive MS) and randomized into either treatment or placebo group to receive six IT injections of autologous MSC-NPs or saline every two months. The primary outcome was EDSS Plus, defined by improvement in EDSS, timed 25-foot walk (T25FW) or nine-hole peg test. Secondary outcomes included the individual components of EDSS Plus, the six-minute walk test (6MWT), urodynamics testing, and brain atrophy measurement.

RESULTS

Subjects were randomized into MSC-NP (n = 27) or saline (n = 27) groups. There was no difference in EDSS Plus improvement between the MSC-NP (33%) and saline (37%) groups. Exploratory subgroup analysis demonstrated that in subjects who require assistance for ambulation (EDSS 6.0-6.5) there was a significantly higher percentage of improvement in T25FW and 6MWT in the MSC-NP group (3.7% ± 23.1% and - 9.2% ± 18.2%) compared to the saline group (-54.4% ± 70.5% and - 32.1% ± 30.0%), (p = 0.030 and p = 0.036, respectively). IT-MSC-NP treatment was also associated with improved bladder function and reduced rate of grey matter atrophy on brain MRI. Biomarker analysis demonstrated increased MMP9 and decreased CCL2 levels in the cerebrospinal fluid following treatment.

CONCLUSION

Results from exploratory outcomes suggest that IT-MSC-NP treatment may be associated with a therapeutic response in a subgroup of MS patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03355365, registered November 14, 2017, https://clinicaltrials.gov/study/NCT03355365?term=NCT03355365&rank=1 .

Quantitative and structural changes of blood platelet cytoskeleton proteins in multiple sclerosis (MS)

Epidemiological studies show that cardiovascular events related to platelet hyperactivity remain the leading causes of death among multiple sclerosis (MS) patients. Quantitative or structural changes of platelet cytoskeleton alter their morphology and function. Here, we demonstrated, for the first time, the structural changes in MS platelets that may be related to their hyperactivity. MS platelets were found to form large aggregates compared to control platelets. In contrast to the control, the images of overactivated, irregularly shaped MS platelets show changes in the cytoskeleton architecture, fragmented microtubule rings. Furthermore, MS platelets have long and numerous pseudopodia rich in actin filaments. We showed that MS platelets and megakaryocytes, overexpress β1-tubulin and β-actin mRNAs and proteins and have altered post-translational modification patterns. Moreover, we identified two previously undisclosed mutations in the gene encoding β1-tubulin in MS. We propose that the demonstrated structural changes of platelet cytoskeleton enhance their ability to adhere, aggregate, and degranulate fueling the risk of adverse cardiovascular events in MS.

Motor Evoked Potential-A Pilot Study Looking at Reliability and Clinical Correlations in Multiple Sclerosis

PURPOSE

Multiple sclerosis (MS) is a clinically heterogeneous disease. Biomarkers that can assess pathological processes that are unseen with conventional imaging remain an unmet need in MS disease management. Motor evoked potentials (MEPs) could be such a biomarker. To determine and follow longitudinal MEP reliability and correlations with clinical measures in MS patients.

METHODS

This is a single-center study in alemtuzumab-treated MS patients to evaluate temporal reliability of MEPs, identify MEP minimum detectible differences, and explore correlations with existing clinical scales. Ten MS patients recently treated with alemtuzumab were evaluated every 6 months over 3 years. Clinical evaluations consisted of expanded disability status scale, timed 25-foot walk, 6-minute walk, and nine-hole peg test. MEPs were measured twice, 2 weeks apart, every 6 months.

RESULTS

Eight patients completed all 3 years of study. The intraclass correlation coefficient for MEP parameters ranged from 0.76 to 0.98. TA latency and amplitude with facilitation significantly and strongly correlated with all clinical measures, whereas the MEP duration modestly correlated. Biceps latency with facilitation significantly and moderately correlated with 9-hole peg test. Longitudinal correlations demonstrated good predictive values for either clinical deterioration or improvement.

CONCLUSIONS

MEPs have excellent intrapatient and intrarater reliability, and TA MEPs significantly and strongly correlated with expanded disability status scale, 6-minute walk, and timed 25-foot walk, whereas biceps MEPs significantly and moderately correlated with nine-hole peg test. Further studies using larger cohorts of MS patients are indicated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, Identifier: NCT02623946.

Understanding the Symptoms and Impacts Experienced by People with Relapsing-Remitting MS: A Qualitative Investigation Using Semi-Structured Interviews

INTRODUCTION

Multiple sclerosis (MS) is a disabling disease with unpredictable clinical manifestations. As clinical assessments may not fully capture the impact of MS on quality of life, they can be complemented by patient-reported outcome (PRO) measures to provide a more comprehensive picture of MS disease state and impact. The objectives of this study were to explore the experiences of people with relapsing-remitting MS, including symptoms and impacts on daily life, and to provide a conceptual model of MS outcomes.

METHODS

A literature review of studies that evaluated the experiences of people with MS was completed and combined with semi-structured concept elicitation interviews conducted with 14 people with relapsing-remitting MS in the USA.

RESULTS

The average age of the 14 participants was 43.9 (range 25-64) years, most were White (78.6%) and female (78.6%), and the mean duration since diagnosis was 6.6 (2-10) years. The most bothersome symptoms identified included fatigue (n = 9), cognitive dysfunction (n = 5), mobility/difficulty with walking (n = 3), and vision problems (n = 3). The most commonly reported impacts on daily life were balance problems/instability (n = 13), work life/productivity (n = 12), difficulty walking (n = 11), daily activities/household chores (n = 11), and leisure activities (n = 10).

CONCLUSION

There was a high frequency of concepts associated with physical function, fatigue, and sensory-motor actions. A conceptual model was developed that captures the disease symptoms, impairments, and impacts identified in the interviews as well as known processes and symptoms identified in the literature search. This model underpins the appropriateness of PRO instruments, such as the PROMIS Fatigue (MS) 8a and PROMIS Physical Function (MS) 15a, which evaluate symptoms and impacts that matter most to people with MS.

An update on the role of magnetic resonance imaging in predicting and monitoring multiple sclerosis progression

INTRODUCTION

While magnetic resonance imaging (MRI) is established in diagnosing and monitoring disease activity in multiple sclerosis (MS), its utility in predicting and monitoring disease progression is less clear.

AREAS COVERED

The authors consider changing concepts in the phenotypic classification of MS, including progression independent of relapses; pathological processes underpinning progression; advances in MRI measures to assess them; how well MRI features explain and predict clinical outcomes, including models that assess disease effects on neural networks, and the potential role for machine learning.

EXPERT OPINION

Relapsing-remitting and progressive MS have evolved from being viewed as mutually exclusive to having considerable overlap. Progression is likely the consequence of several pathological elements, each important in building more holistic prognostic models beyond conventional phenotypes. MRI is well placed to assess pathogenic processes underpinning progression, but we need to bridge the gap between MRI measures and clinical outcomes. Mapping pathological effects on specific neural networks may help and machine learning methods may be able to optimize predictive markers while identifying new, or previously overlooked, clinically relevant features. The ever-increasing ability to measure features on MRI raises the dilemma of what to measure and when, and the challenge of translating research methods into clinically useable tools.

Bile acid metabolites predict multiple sclerosis progression and supplementation is safe in progressive disease

Background

Bile acid metabolism is altered in multiple sclerosis (MS) and tauroursodeoxycholic acid (TUDCA) supplementation ameliorated disease in mouse models of MS.

Methods

Global metabolomics was performed in an observational cohort of people with MS followed by pathway analysis to examine relationships between baseline metabolite levels and subsequent brain and retinal atrophy. A double-blind, placebo-controlled trial, was completed in people with progressive MS (PMS), randomized to receive either TUDCA (2g daily) or placebo for 16 weeks. Participants were followed with serial clinical and laboratory assessments. Primary outcomes were safety and tolerability of TUDCA, and exploratory outcomes included changes in clinical, laboratory and gut microbiome parameters.

Results

In the observational cohort, higher primary bile acid levels at baseline predicted slower whole brain, brain substructure and specific retinal layer atrophy. In the clinical trial, 47 participants were included in our analyses (21 in placebo arm, 26 in TUDCA arm). Adverse events did not significantly differ between arms (p=0.77). The TUDCA arm demonstrated increased serum levels of multiple bile acids. No significant differences were noted in clinical or fluid biomarker outcomes. Central memory CD4+ and Th1/17 cells decreased, while CD4+ naïve cells increased in the TUDCA arm compared to placebo. Changes in the composition and function of gut microbiota were also noted in the TUDCA arm compared to placebo.

Conclusion

Bile acid metabolism in MS is linked with brain and retinal atrophy. TUDCA supplementation in PMS is safe, tolerable and has measurable biological effects that warrant further evaluation in larger trials with a longer treatment duration.

Disease progression in the first 5 years of treatment in multiple sclerosis: Predictive value of early brain and lesion volume changes

BACKGROUND

Whether the degree of inflammation (and its resolution) and neurodegeneration after treatment initiation predicts disease progression in multiple sclerosis (MS) remains unclear.

OBJECTIVES

To assess the predictive value of magnetic resonance imaging (MRI)-derived brain and lesion volume (LV) changes in years 1 and 2 of treatment for disease progression.

METHODS

Patients receiving early interferon beta-1a treatment in REFLEX/REFLEXION (N = 262) were included. Predictive regression models included new/enlarging LV (positive activity), disappearing/shrinking LV (negative activity), and global/central atrophy during years 1 and 2.

RESULTS

Faster global atrophy and/or pseudo-atrophy and positive lesion activity in years 1 and 2 related to an increased probability and faster conversion to clinically definite multiple sclerosis (CDMS). Negative lesion activity in year 1 and slower central atrophy in year 2 were predictive of confirmed disability progression (9-Hole Peg Test). Positive lesion activity in year 2 was predictive of faster global atrophy, while positive lesion activity in years 1 and 2 was predictive of faster central atrophy.

CONCLUSIONS

A higher degree of global atrophy and/or pseudo-atrophy in year 1 was predictive of CDMS. Positive lesion activity in any year was related to CDMS and neurodegeneration. Disability was related to negative lesion activity in year 1 and slower central atrophy in year 2.

Multimodal MRI study on the relation between WM integrity and connected GM atrophy and its effect on disability in early multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is characterized by pathology in white matter (WM) and atrophy of grey matter (GM), but it remains unclear how these processes are related, or how they influence clinical progression.

OBJECTIVE

To study the spatial and temporal relationship between GM atrophy and damage in connected WM in relapsing-remitting (RR) MS in relation to clinical progression.

METHODS

Healthy control (HC) and early RRMS subjects visited our center twice with a 1-year interval for MRI and clinical examinations, including the Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Functional Composite (MSFC) scores. RRMS subjects were categorized as MSFC decliners or non-decliners based on ΔMSFC over time. Ten deep (D)GM and 62 cortical (C) GM structures were segmented and probabilistic tractography was performed to identify the connected WM. WM integrity was determined per tract with, amongst others, fractional anisotropy (FA), mean diffusivity (MD), neurite density index (NDI), and myelin water fraction (MWF). Linear mixed models (LMMs) were used to investigate GM and WM differences between HC and RRMS, and between MSFC decliners and non-decliners. LMM was also used to test associations between baseline WM z-scores and changes in connected GM z-scores, and between baseline GM z-scores and changes in connected WM z-scores, in HC/RRMS subjects and in MSFC decliners/non-decliners.

RESULTS

We included 13 HCs and 31 RRMS subjects with an average disease duration of 3.5 years and a median EDSS of 3.0. Fifteen RRMS subjects showed declining MSFC scores over time, and they showed higher atrophy rates and greater WM integrity loss compared to non-decliners. Lower baseline WM integrity was associated with increased CGM atrophy over time in RRMS, but not in HC subjects. This effect was only seen in MSFC decliners, especially when an extended WM z-score was used, which included FA, MD, NDI and MWF. Baseline GM measures were not significantly related to WM integrity changes over time in any of the groups.

DISCUSSION

Lower baseline WM integrity was related to more cortical atrophy in RRMS subjects that showed clinical progression over a 1-year follow-up, while baseline GM did not affect WM integrity changes over time. WM damage, therefore, seems to drive atrophy more than conversely.

No Evidence of Disease Activity (NEDA) as a Clinical Assessment Tool for Multiple Sclerosis: Clinician and Patient Perspectives [Narrative Review]

The emergence of high-efficacy therapies for multiple sclerosis (MS), which target inflammation more effectively than traditional disease-modifying therapies, has led to a shift in MS management towards achieving the outcome assessment known as no evidence of disease activity (NEDA). The most common NEDA definition, termed NEDA-3, is a composite of three related measures of disease activity: no clinical relapses, no disability progression, and no radiological activity. NEDA has been frequently used as a composite endpoint in clinical trials, but there is growing interest in its use as an assessment tool to help patients and healthcare professionals navigate treatment decisions in the clinic. Raising awareness about NEDA may therefore help patients and clinicians make more informed decisions around MS management and improve overall MS care. This review aims to explore the potential utility of NEDA as a clinical decision-making tool and treatment target by summarizing the literature on its current use in the context of the expanding treatment landscape. We identify current challenges to the use of NEDA in clinical practice and detail the proposed amendments, such as the inclusion of alternative outcomes and biomarkers, to broaden the clinical information captured by NEDA. These themes are further illustrated with the real-life perspectives and experiences of our two patient authors with MS. This review is intended to be an educational resource to support discussions between clinicians and patients on this evolving approach to MS-specialized care.

Opportunities and challenges: mesenchymal stem cells in the treatment of multiple sclerosis

Multiple sclerosis (MS) was once considered an untreatable disease. Through years of research, many drugs have been discovered and are widely used for the treatment of MS. However, the current treatment can only alleviate the clinical symptoms of MS and has serious side effects. Mesenchymal stem cells (MSCs) provide neuroprotection by migrating to injured tissues, suppressing inflammation, and fostering neuronal repair. Therefore, MSCs therapy holds great promise for MS treatment. This review aimed to assess the feasibility and safety of use of MSCs in MS treatment as well as its development prospect in clinical treatment by analysing the existing clinical studies.

Management of multiple sclerosis fatigue in the digital age: from assessment to treatment

Fatigue is one of the most disabling symptoms of Multiple Sclerosis (MS), affecting more than 80% of patients over the disease course. Nevertheless, it has a multi-faceted and complex nature, making its diagnosis, evaluation, and treatment extremely challenging in clinical practice. In the last years, digital supporting tools have emerged to support the care of people with MS. These include not only smartphone or table-based apps, but also wearable devices or novel techniques such as virtual reality. Furthermore, an additional effective and cost-efficient tool for the therapeutic management of people with fatigue is becoming increasingly available. Virtual reality and e-Health are viable and modern tools to both assess and treat fatigue, with a variety of applications and adaptability to patient needs and disability levels. Most importantly, they can be employed in the patient's home setting and can not only bridge clinic visits but also be complementary to the monitoring and treatment means for those MS patients who live far away from healthcare structures. In this narrative review, we discuss the current knowledge and future perspectives in the digital management of fatigue in MS. These may also serve as sources for research of novel digital biomarkers in the identification of disease activity and progression.

Progression risk stratification with six-minute walk gait speed trajectory in multiple sclerosis

Background

Multiple Sclerosis (MS) disease progression has notable heterogeneity among patients and over time. There is no available single method to predict the risk of progression, which represents a significant and unmet need in MS.

Methods

MS and healthy control (HC) participants were recruited for a 2-year observational study. A latent-variable growth mixture model (GMM) was applied to cluster baseline 6-min walk gait speed trajectories (6MWGST). MS patients within different 6 MWGST clusters were identified and stratified. The group membership of these MS patients was compared against 2-year confirmed-disease progression (CDP). Clinical and patient-reported outcome (PRO) measures were compared between HC and MS subgroups over 2 years.

Results

62 MS and 41 HC participants completed the 2-year study. Within the MS cohort, 90% were relapsing MS. Two distinct patterns of baseline 6 MWGST emerged, with one cluster displaying a faster gait speed and a typical "U" shape, and the other showing a slower gait speed and a "flattened" 6 MWGST curve. We stratified MS participants in each cluster as low- and high-risk progressors (LRP and HRP, respectively). When compared against 2-year CDP, our 6 MWGST approach had 71% accuracy and 60% positive predictive value. Compared to the LRP group, those MS participants stratified as HRP (15 out of 62 MS participants), were on average 3.8 years older, had longer MS disease duration and poorer baseline performance on clinical outcomes and PROs scores. Over the subsequent 2 years, only the HRP subgroup showed a significant worsened performance on 6 MW, clinical measures and PROs from baseline.

Conclusion

Baseline 6 MWGST was useful for stratifying MS participants with high or low risks for progression over the subsequent 2 years. Findings represent the first reported single measure to predict MS disease progression with important potential applications in both clinical trials and care in MS.

Multiple sclerosis functional tests and their comparability with self-administered values: A pilot study

Introduction

Neurological impairment in multiple sclerosis is highly variable among patients and over time it is difficult to quantify. The Multiple Sclerosis Outcome Assessment Consortium established sensitive, cost-effective, clinically significant, and reproducible measures of different functional systems to measure outcomes in clinical trials. However, their use in clinical care routines is not widespread due to time and training constraints.

Objective

To evaluate the self-administration feasibility of the timed 25-foot walking, symbol-digit-modality, and 9-peg hole tests in healthy individuals.

Materials and methods

We performed a descriptive pilot study. Healthy individuals between 18 and 80 years of age were included. The Timed 25-Foot Walking Test (T25- FWT), the Symbol Digit Modality Test (SDMT), and the Nine-Hole Peg Test (9-HPT) (using the dominant and non-dominant hand) were administered by a trained physician, who also instructed the subjects about test self-administration. The correlation and agreement, between the guided and self-administered tests were assessed with Pearson and Spearman coefficients and the Bland-Altman method.

Results

Thirty-eight healthy volunteers were included. The median age was 36 (range: 23-55) years old, and 55.26% were female. The correlation coefficient between guided and selfadministered tests was 0.37 for the T25-FWT (p=0.01), 0.54 for the SDMT (p<0.001), and 0.64 and 0.65 for the 9-HPT, in the dominant and non-dominant hands, respectively (p<0,001). Both forms of administration were concordant for the T25-FWT (95%CI: -1,49 to 1,43), the 9-HPT with dominant hand (95%CI: -5,23 to 4,09), the 9-HPT with non-dominant hand (95%CI: -7,75 to 7,14) and the SDMT (95% CI: -20,94 to 24,10).

Conclusions

We provide a proof of concept related to the feasibility of the selfadministration of the T25-FWT, the 9-HPT, and the SDMT, as a tool to improve monitoring in routine clinical practice.

Neurodegeneration and its potential markers in the diagnosing of secondary progressive multiple sclerosis. A review

Approximately 70% of relapsing-remitting multiple sclerosis (RRMS) patients will develop secondary progressive multiple sclerosis (SPMS) within 10-15 years. This progression is characterized by a gradual decline in neurological functionality and increasing limitations of daily activities. Growing evidence suggests that both inflammation and neurodegeneration are associated with various pathological processes throughout the development of MS; therefore, to delay disease progression, it is critical to initiate disease-modifying therapy as soon as it is diagnosed. Currently, a diagnosis of SPMS requires a retrospective assessment of physical disability exacerbation, usually over the previous 6-12 months, which results in a delay of up to 3 years. Hence, there is a need to identify reliable and objective biomarkers for predicting and defining SPMS conversion. This review presents current knowledge of such biomarkers in the context of neurodegeneration associated with MS, and SPMS conversion.

Assessment of Multiple Aspects of Upper Extremity Function Independent From Ambulation in Patients With Multiple Sclerosis

BACKGROUND

Upper extremity function (UEF) is often compromised in multiple sclerosis (MS), although its importance is regularly underrecognized relative to ambulation. We explored the concurrent presence of impairment in UEF and ambulation by examining various aspects of UEF across different levels of ambulation.

METHODS

The cohort consisted of 247 patients with clinically definite MS or clinically isolated syndrome according to the revised 2010 McDonald criteria. The Nine-Hole Peg Test and the Expanded Disability Status Scale were used to stratify patients into clinically different subgroups. For UEF, cerebellar function (finger-to-nose test), pyramidal function (pronator drift test), and the ability to perform a task of activities of daily living (drinking-from-cup test) were examined. Patient-reported limitations of UEF in daily life were assessed using the Arm Function in Multiple Sclerosis Questionnaire.

RESULTS

Patients in more severely impaired ambulation groups displayed poorer performance on all UEF measures. Although most patients had normal to mild (n = 147) or moderate (n = 46) ambulatory impairment, 87.7% exhibited some level of UEF impairment as defined using the Nine-Hole Peg Test. Most patients had mild UEF impairment (n = 174), accounting for the largest proportion in all ambulation groups (51.9%-77.8%).

CONCLUSIONS

A distinct pattern of impairment was found for ambulation and multiple aspects of UEF. Independent assessment of multiple aspects of disability may be helpful in treatment decision-making and could support the development of rehabilitation strategies that specifically target UEF impairment.

Serum Neurofilaments and OCT Metrics Predict EDSS-Plus Score Progression in Early Relapse-Remitting Multiple Sclerosis

(1) Background: Early disability accrual in RRMS patients is frequent and is associated with worse long-term prognosis. Correctly identifying the patients that present a high risk of early disability progression is of utmost importance, and may be aided by the use of predictive biomarkers. (2) Methods: We performed a prospective cohort study that included newly diagnosed RRMS patients, with a minimum follow-up period of one year. Biomarker samples were collected at baseline, 3-, 6- and 12-month follow-ups. Disability progression was measured using the EDSS-plus score. (3) Results: A logistic regression model based on baseline and 6-month follow-up sNfL z-scores, RNFL and GCL-IPL thickness and BREMSO score was statistically significant, with χ2(4) = 19.542, p < 0.0001, R2 = 0.791. The model correctly classified 89.1% of cases, with a sensitivity of 80%, a specificity of 93.5%, a positive predictive value of 85.7% and a negative predictive value of 90.62%. (4) Conclusions: Serum biomarkers (adjusted sNfL z-scores at baseline and 6 months) combined with OCT metrics (RNFL and GCL-IPL layer thickness) and the clinical score BREMSO can accurately predict early disability progression using the EDSS-plus score for newly diagnosed RRMS patients.

Dimethyl fumarate treatment of primary progressive multiple sclerosis: results of an open-label extension study

INTRODUCTION

Dimethyl fumarate treatment is approved in Europe for patients with relapsing-remitting multiple sclerosis (MS) and in the US for relapsing forms of MS. We recently published the results of the first randomized placebo-controlled trial of 48 weeks of treatment with dimethyl fumarate or placebo in primary progressive MS (PPMS) (clinicaltrial.gov NCT02959658). The placebo-controlled phase of the trial did not meet its primary endpoint (reduction in cerebrospinal fluid concentrations of neurofilament light chain [NFL]).

AIM

To investigate the effects of dimethyl fumarate treatment in the open-label extension phase of the trial (week 48-96), where all patients were treated with DMF.

METHODS

Reported data are from screening, week 48, and week 96 visits. Patients were clinically evaluated with Expanded Disability Status Scale (EDSS), 9-Hole Peg Test (9HPT), Timed 25-Foot Walk (T25FW) test, Symbol Digit Modalities Test (SDMT), California Verbal Learning Test, and Brief Visuospatial Memory-Revised. Serum NFL concentrations were measured by single-molecule array analysis. MRI was performed on a 3 tesla MRI scanner and included: new/enlarging lesions, volume of lesions, cortical grey matter, putamen, thalamus, and normal-appearing white matter, and additional diffusion tensor imaging and magnetization transfer ratio measures.

RESULTS

Forty-two patients entered the open-label treatment phase, and 33 patients (61%) had complete data sets at week 96. The remaining 39% did not complete the trial and were not evaluated at week 96. We found no evidence of differences in clinical and MRI measures between patients initially treated with dimethyl fumarate and patients initially treated with placebo from baseline to week 48 and from week 48-96, where all patients were treated with dimethyl fumarate. Serum NFL concentrations remained stable in both groups over 96 weeks. Assessed with either EDSS, T25FW, or 9HPT at week 96, progression was observed for 14 patients (45%). Interestingly, another 15 patients (46%) had improvement in one or more of these domains. Applying a cut-off of 8 points, 2 (6%) patients worsened on SDMT, 25 (78%) did not change, and 5 (16%) improved.

CONCLUSIONS

Dimethyl fumarate treatment showed no effects on neither clinical nor MRI outcomes or changes in serum concentrations of NFL. An expected number of patients showed evidence of progression on standard clinical scales; however, this was matched by an equal number of patients improving. The reasons for the physical improvement in an unexpectedly high proportion of patients must be addressed in future studies.

Gut microbiome composition is associated with long-term disability worsening in multiple sclerosis

Predicting the long-term outcome of multiple sclerosis (MS) remains an important challenge to this day. As the gut microbiota is emerging as a potential player in MS, we investigated in this study whether gut microbial composition at baseline is related to long-term disability worsening in a longitudinal cohort of 111 MS patients. Fecal samples and extensive host metadata were collected at baseline and 3 months post-baseline, with additional repeated neurological measurements performed over (median) 4.4 y. Worsening (with EDSS-Plus) occurred in 39/95 patients (outcome undetermined for 16 individuals). The inflammation-associated, dysbiotic Bacteroides 2 enterotype (Bact2) was detected at baseline in 43.6% of worsened patients, while only 16.1% of non-worsened patients harbored Bact2. This association was independent of identified confounders, and Bact2 was more strongly associated with EDSS-Plus than neurofilament light chain (NfL) plasma levels. Furthermore, using fecal sampling performed 3 months post-baseline, we observed Bact2 to be relatively stable, suggesting its potential use as a prognostic biomarker in MS clinical practice.

Associations between myelin water imaging and measures of fall risk and functional mobility in multiple sclerosis

BACKGROUND AND PURPOSE

Myelin water fraction (MWF) deficits as measured by myelin water imaging (MWI) have been related to worse motor function in persons with multiple sclerosis (PwMS). However, it is unknown if measures from MWI metrics in motor areas relate to fall risk measures in PwMS. The objective of this study was to examine the relationship between MWI measures in motor areas to performance on clinical measures of fall risk and disability in PwMS.

METHODS

Sixteen individuals with relapsing-remitting MS participated (1 male, 15 female; age 47.1 years [12.3]; Expanded Disability Status Scale 4.0 [range 0-6.5]) and completed measures of walking and fall risk (Timed 25 Foot Walk [T25FW] and Timed Up and Go). MWF and the geometric mean of the intra-/extracellular water T₂ (geomT_2IEW ) values reflecting myelin content and contribution of large-diameter axons/density, respectively, were assessed in three motor-related regions.

RESULTS

The geomT_2IEW of the corticospinal tract (r = -.599; p = .018) and superior cerebellar peduncles (r = -.613; p = .015) demonstrated significant inverse relationships with T25FW, suggesting that decreased geomT_2IEW was related to slower walking. Though not significant, MWF in the corticospinal tract and superior cerebellar peduncles also demonstrated fair relationships with the T25FW, suggesting that worse performance on the T25FW was associated with lower MWF values.

CONCLUSIONS

MWI of key motor regions was associated with walking performance in PwMS. Further MWI studies are needed to identify relationships between pathology and clinical function in PwMS to guide targeted rehabilitation therapies aimed at preventing falls.

Unmet needs and gaps in the identification of secondary progression in multiple sclerosis: a Southern Italy healthcare professionals' perspective

OBJECTIVE

Multiple sclerosis (MS) is a chronic disease with different clinical courses and a tendency to worsening. The relapsing-remitting MS presents acute onset and relapses of neurological symptoms, followed by their remission. This form can convert to secondary progressive MS (SPMS) with irreversible neurological worsening and disability. The identification of signs, symptoms, markers of progression, and strategies to manage MS patients is mandatory to allow early identification of those at higher risk of conversion to SPMS, for prompt intervention to cope with the progression of the disease.

METHODS

A panel of Italian experts from Southern Italy have reviewed the current knowledge on MS and its management and identified the crucial tools for SPMS recognition.

RESULTS

More effective communication between patients and clinicians should be established, with the support of digital tools. Moreover, the improvement in the clinical use of biomarkers for progression (cellular structures and tissue organization, such as neurofilaments and chitinase 3-like 1, axonal and neurons density) and of instrumental analyses for recognition of whole-brain atrophy, chronic active lesions, spinal cord lesions and atrophy, and the improvement the combination of the Expanded Disability Status Scale and the evaluation of cognitive dysfunction are discussed.

CONCLUSION

Given the availability of a pharmacological option, adequate education both for patients, regarding the evolution of the disease and the specific treatment, and for professionals, to allow more effective and sensitive communication and the best use of diagnostic and management tools, could represent a strategy to improve patient management and their quality of life.

Modulation of the Microglial Nogo-A/NgR Signaling Pathway as a Therapeutic Target for Multiple Sclerosis

Current therapeutics targeting chronic phases of multiple sclerosis (MS) are considerably limited in reversing the neural damage resulting from repeated inflammation and demyelination insults in the multi-focal lesions. This inflammation is propagated by the activation of microglia, the endogenous immune cell aiding in the central nervous system homeostasis. Activated microglia may transition into polarized phenotypes; namely, the classically activated proinflammatory phenotype (previously categorized as M1) and the alternatively activated anti-inflammatory phenotype (previously, M2). These transitional microglial phenotypes are dynamic states, existing as a continuum. Shifting microglial polarization to an anti-inflammatory status may be a potential therapeutic strategy that can be harnessed to limit neuroinflammation and further neurodegeneration in MS. Our research has observed that the obstruction of signaling by inhibitory myelin proteins such as myelin-associated inhibitory factor, Nogo-A, with its receptor (NgR), can regulate microglial cell function and activity in pre-clinical animal studies. Our review explores the microglial role and polarization in MS pathology. Additionally, the potential therapeutics of targeting Nogo-A/NgR cellular mechanisms on microglia migration, polarization and phagocytosis for neurorepair in MS and other demyelination diseases will be discussed.

Overall Disability Response Score: An integrated endpoint to assess disability improvement and worsening over time in patients with multiple sclerosis

BACKGROUND

Overall Disability Response Score (ODRS) is a composite endpoint including Expanded Disability Status Scale, Timed 25-foot Walk, and 9-Hole Peg Test, designed to quantify both disability improvement and worsening in multiple sclerosis (MS).

OBJECTIVE

To assess the sensitivity and clinical meaningfulness of ODRS using natalizumab Phase 3 data sets (AFFIRM in relapsing-remitting MS and ASCEND in secondary progressive MS).

METHODS

Differences in ODRS over 96 weeks, ODRS at Week 96, and slope of ODRS change per year between natalizumab and placebo groups were analyzed. Correlation between ODRS and changes in patient-reported outcomes was also analyzed.

RESULTS

The difference (95% confidence interval (CI)) in the ODRS over 96 weeks between natalizumab and placebo groups was 0.34 (0.21-0.46) in AFFIRM (p < 0.001), and 0.18 (0.03-0.34) in ASCEND (p = 0.021). Significant differences between treatment arms were also observed in ODRS at Week 96 and in the slope of change per year in both studies. There was a significant linear correlation between ODRS at Week 96 and the change from baseline in both the physical and mental components of the 36-item Short Form Survey (SF-36) in both studies.

CONCLUSION

This analysis supports ODRS as a sensitive and potentially clinically meaningful disability outcome measure in MS.

Progressive Multiple Sclerosis

PURPOSE OF REVIEW

This article provides an update on progressive forms of multiple sclerosis (MS) commonly referred to as primary progressive MS and secondary progressive MS. It discusses the importance of diagnosing and detecting progression early, the similarities between progressive forms, challenges in detecting progression, factors that could augment progression, and the importance of disease-modifying therapies in patients with evidence of active progressive MS. It also discusses the overall care of progressive MS.

RECENT FINDINGS

The pathogenesis of primary progressive MS and secondary progressive MS is overlapping, and in both presentations, patients with relapses or focal MRI activity are classified as having active, progressive MS. All currently approved disease-modifying therapies are indicated for active secondary progressive MS. The therapeutic opportunity of anti-inflammatory drugs for the treatment of progressive MS is enhanced in those who are younger and have a shorter disease duration. Vascular comorbidities may contribute to progression in MS.

SUMMARY

Several challenges remain in the diagnosis, follow-up, and treatment of progressive MS. Early identification of active progressive MS is needed to maximize treatment benefit. The advantages of optimal comorbidity management (eg, hypertension, hyperlipidemia) in delaying progression are uncertain. Clinical care guidelines for advanced, severe MS are lacking.

Consensus on early detection of disease progression in patients with multiple sclerosis

Background

Early identification of the transition from relapsing-remitting multiple sclerosis (RRMS) to secondary progressive MS (SPMS) can be challenging for clinicians, as diagnostic criteria for SPMS are primarily based on physical disability and a holistic interpretation.

Objective

To establish a consensus on patient monitoring to identify promptly disease progression and the most useful clinical and paraclinical variables for early identification of disease progression in MS.

Methods

A RAND/UCLA Appropriateness Method was used to establish the level of agreement among a panel of 15 medical experts in MS. Eighty-three items were circulated to the experts for confidential rating of the grade of agreement and recommendation. Consensus was defined when ≥66% agreement or disagreement was achieved.

Results

Consensus was reached in 72 out of 83 items (86.7%). The items addressed frequency of follow-up visits, definition of progression, identification of clinical, cognitive, and radiological assessments as variables of suspected or confirmed SPMS diagnosis, the need for more accurate assessment tools, and the use of promising molecular and imaging biomarkers to predict disease progression and/or diagnose SPMS.

Conclusion

Consensus achieved on these topics could guide neurologists to identify earlier disease progression and to plan targeted clinical and therapeutic interventions during the earliest stages of SPMS.

Does Ocrelizumab Limit Multiple Sclerosis Progression? Current Evidence from Clinical, MRI, and Fluid Biomarkers

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating, and neurodegenerative disease affecting the central nervous system, often characterized by the accumulation of irreversible clinical disability over time. In recent years, there has been a dramatic evolution in several key concepts of MS treatment. The demonstration of the effects of ocrelizumab, a selective monoclonal antibody against CD20+ B cells, has significantly modified our knowledge of the immune-pathophysiology of MS and has provided a new therapeutic target for relapsing and progressive MS patients. Emerging findings suggest that, besides its strong anti-inflammatory activity, ocrelizumab may limit disability progression and may exert beneficial effects on cognitive function, fatigue, and quality of life of MS patients. The significant reductions of the rate of global and regional brain atrophy and of serum neurofilament light chain levels, which were found to be partially independent of overt inflammatory activity, suggest that this treatment may also limit neuro-axonal damage. By discussing the most recent evidence regarding the effects of ocrelizumab on clinical measures as well as on magnetic resonance imaging and fluid biomarkers, this review summarizes current knowledge on the possible mechanisms underlying the effects of ocrelizumab in limiting MS progression and neurodegeneration.

A Narrative Review on Axonal Neuroprotection in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) resulting in demyelination and neurodegeneration. The therapeutic strategy is now largely based on reducing inflammation with immunosuppressive drugs. Unfortunately, when disease progression is observed, no drug offers neuroprotection apart from its anti-inflammatory effect. In this review, we explore current knowledge on the assessment of neurodegeneration in MS and look at putative targets that might prove useful in protecting the axon from degeneration. Among them, Bruton's tyrosine kinase inhibitors, anti-apoptotic and antioxidant agents, sex hormones, statins, channel blockers, growth factors, and molecules preventing glutamate excitotoxicity have already been studied. Some of them have reached phase III clinical trials and carry a great message of hope for our patients with MS.

Early use of high-efficacy disease‑modifying therapies makes the difference in people with multiple sclerosis: an expert opinion

Multiple sclerosis (MS) is a chronic and progressive neurological disease that is characterized by neuroinflammation, demyelination and neurodegeneration occurring from the earliest phases of the disease and that may be underestimated. MS patients accumulate disability through relapse-associated worsening or progression independent of relapse activity. Early intervention with high-efficacy disease-modifying therapies (HE-DMTs) may represent the best window of opportunity to delay irreversible central nervous system damage and MS-related disability progression by hindering underlying heterogeneous pathophysiological processes contributing to disability progression. In line with this, growing evidence suggests that early use of HE-DMTs is associated with a significant greater reduction not only of inflammatory activity (clinical relapses and new lesion formation at magnetic resonance imaging) but also of disease progression, in terms of accumulation of irreversible clinical disability and neurodegeneration compared to delayed HE-DMT use or escalation strategy. These beneficial effects seem to be associated with acceptable long-term safety risks, thus configuring this treatment approach as that with the most positive benefit/risk profile. Accordingly, it should be mandatory to treat people with MS early with HE-DMTs in case of prognostic factors suggestive of aggressive disease, and it may be advisable to offer an HE-DMT to MS patients early after diagnosis, taking into account drug safety profile, disease severity, clinical and/or radiological activity, and patient-related factors, including possible comorbidities, family planning, and patients’ preference in agreement with the EAN/ECTRIMS and AAN guidelines. Barriers for an early use of HE-DMTs include concerns for long-term safety, challenges in the management of treatment initiation and monitoring, negative MS patients’ preferences, restricted access to HE-DMTs according to guidelines and regulatory rules, and sustainability. However, these barriers do not apply to each HE-DMT and none of these appear insuperable.

Plasma glial fibrillary acidic protein and neurofilament light chain in relation to disability worsening in multiple sclerosis

Background:

Predicting disability worsening in multiple sclerosis (MS) remains an important challenge. Glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) seem promising biomarkers. Studies investigating blood GFAP in relation to longitudinal outcome measures in MS are scarce.

Objective:

To compare plasma-GFAP (p-GFAP) and plasma-NfL (p-NfL) levels in relation to sustained disability worsening.

Methods:

We measured baseline p-GFAP and p-NfL in a prospective cohort of 115 individuals with MS and 30 matched controls, using Single Molecule Array (Simoa). Disability worsening was defined as an increase in at least one of three measures (Expanded Disability Status Scale, Timed 25-foot walk, 9-Hole Peg test), confirmed after 6 months and persistent upon data closure.

Results:

In a multivariable Cox proportional-hazards model, p-GFAP was not significantly associated with sustained disability worsening after 4.40 ± 0.82 years, while p-NfL (HR = 1.046, p = 0.001), EDSS (HR = 1.24, p = 0.039), and disease duration (HR = 1.048, p = 0.017) were. Area under the curve of ROC curves in relation to worsening was 0.61 for p-GFAP ( p = 0.031) and 0.63 for p-NfL ( p = 0.015). Kaplan–Meier curves showed similar patterns for both proteins.

Conclusion:

p-NfL emerged as a significant explanatory variable for worsening in Cox regression analysis, and p-GFAP did not. Both p-GFAP and p-NfL were related to worsening based on ROC curves.

Deformation-based morphometry identifies deep brain structures protected by ocrelizumab

BACKGROUND

Despite advancements in treatments for multiple sclerosis, insidious disease progression remains an area of unmet medical need, for which atrophy-based biomarkers may help better characterize the progressive biology.

METHODS

We developed and applied a method of longitudinal deformation-based morphometry to provide voxel-level assessments of brain volume changes and identified brain regions that were significantly impacted by disease-modifying therapy.

RESULTS

Using brain MRI data from two identically designed pivotal trials of relapsing multiple sclerosis (total N = 1483), we identified multiple deep brain regions, including the thalamus and brainstem, where volume loss over time was reduced by ocrelizumab (p < 0.05), a humanized anti-CD20 + monoclonal antibody approved for the treatment of multiple sclerosis. Additionally, identified brainstem shrinkage, as well as brain ventricle expansion, was associated with a greater risk for confirmed disability progression (p < 0.05).

CONCLUSIONS

The identification of deep brain structures has a strong implication for developing new biomarkers of brain atrophy reduction to advance drug development for multiple sclerosis, which has an increasing focus on targeting the progressive biology.

Designing Multi-arm Multistage Adaptive Trials for Neuroprotection in Progressive Multiple Sclerosis

There are few treatments shown to slow disability progression in progressive multiple sclerosis (PMS). One challenge has been efficiently testing the pipeline of candidate therapies from preclinical studies in clinical trials. Multi-arm multistage (MAMS) platform trials may accelerate evaluation of new therapies compared to traditional sequential clinical trials. We describe a MAMS design in PMS focusing on selection of interim and final outcome measures, sample size, and statistical considerations. The UK MS Society Expert Consortium for Progression in MS Clinical Trials reviewed recent phase II and III PMS trials to inform interim and final outcome selection and design measures. Simulations were performed to evaluate trial operating characteristics under different treatment effect, recruitment rate, and sample size assumptions. People with MS formed a patient and public involvement group and contributed to the trial design, ensuring it would meet the needs of the MS community. The proposed design evaluates 3 experimental arms compared to a common standard of care arm in 2 stages. Stage 1 (interim) outcome will be whole brain atrophy on MRI at 18 months, assessed for 123 participants per arm. Treatments with sufficient evidence for slowing brain atrophy will continue to the second stage. The stage 2 (final) outcome will be time to 6-month confirmed disability progression, based on a composite clinical score comprising the Expanded Disability Status Scale, Timed 25-Foot Walk test, and 9-Hole Peg Test. To detect a hazard ratio of 0.75 for this primary final outcome with 90% power, 600 participants per arm are required. Assuming one treatment progresses to stage 2, the trial will recruit ≈1,900 participants and last ≈6 years. This is approximately two-thirds the size and half the time of separate 2-arm phase II and III trials. The proposed MAMS trial design will substantially reduce duration and sample size compared to traditional clinical trials, accelerating discovery of effective treatments for PMS. The design was well-received by people with multiple sclerosis. The practical and statistical principles of MAMS trial design may be applicable to other neurodegenerative conditions to facilitate efficient testing of new therapies.

What Have Failed, Interrupted, and Withdrawn Antibody Therapies in Multiple Sclerosis Taught Us?

In the past two decades, monoclonal antibodies (mAbs) have revolutionized the treatment of multiple sclerosis (MS). However, a remarkable number of mAbs failed due to negative study results were withdrawn because of unexpected serious adverse events (SAEs) or due to studies being halted for other reasons. While trials with positive outcomes are usually published in prestigious journals, negative trials are merely published as abstracts or not at all. This review summarizes MS mAbs that have either failed in phase II-III trials, have been interrupted for various reasons, or withdrawn from the market since 2015. The main conclusions that can be drawn from these 'negative' experiences are as follows. mAbs that have been proven to be safe in other autoimmune conditions, will not have the same safety profile in MS due to immunopathogenetic differences in these diseases (e.g., daclizumab). Identification of SAEs in clinical trials is difficult highlighting the importance of phase IV studies. Memory B cells are central players in MS immunopathogenesis (e.g., tabalumab). The pathophysiological mechanisms of disease progression are independent of leukocyte 'outside-in' traffic which drives relapses in MS. Therefore, therapies for progressive MS must be able to sufficiently cross the blood-brain barrier. Sufficiently long trial duration and multicomponent outcome measures are important for clinical studies in progressive MS. The success of trials on remyelination-promoting therapies mainly depends on the sufficient high dose of mAb, the optimal readout for 'proof of concept', time of treatment initiation, and appropriate selection of patients. Failed strategies are highly important to better understand assumed immunopathophysiological mechanisms and optimizing future trial designs.

The Neuroimmunology of Multiple Sclerosis: Fictions and Facts

There have been tremendous advances in the neuroimmunology of multiple sclerosis over the past five decades, which have led to improved diagnosis and therapy in the clinic. However, further advances must take into account an understanding of some of the complex issues in the field, particularly an appreciation of “facts” and “fiction.” Not surprisingly given the incredible complexity of both the nervous and immune systems, our understanding of the basic biology of the disease is very incomplete. This lack of understanding has led to many controversies in the field. This review identifies some of these controversies and facts/fictions with relation to the basic neuroimmunology of the disease (cells and molecules), and important clinical issues. Fortunately, the field is in a healthy transition from excessive reliance on animal models to a broader understanding of the disease in humans, which will likely lead to many improved treatments especially of the neurodegeneration in multiple sclerosis (MS).

Smouldering multiple sclerosis: the ‘real MS’

Using a philosophical approach or deductive reasoning, we challenge the dominant clinico-radiological worldview that defines multiple sclerosis (MS) as a focal inflammatory disease of the central nervous system (CNS). We provide a range of evidence to argue that the ‘real MS’ is in fact driven primarily by a smouldering pathological disease process. In natural history studies and clinical trials, relapses and focal activity revealed by magnetic resonance imaging (MRI) in MS patients on placebo or on disease-modifying therapies (DMTs) were found to be poor predictors of long-term disease evolution and were dissociated from disability outcomes. In addition, the progressive accumulation of disability in MS can occur independently of relapse activity from early in the disease course. This scenario is underpinned by a more diffuse smouldering pathological process that may affect the entire CNS. Many putative pathological drivers of smouldering MS can be potentially modified by specific therapeutic strategies, an approach that may have major implications for the management of MS patients. We hypothesise that therapeutically targeting a state of ‘no evident inflammatory disease activity’ (NEIDA) cannot sufficiently prevent disability accumulation in MS, meaning that treatment should also focus on other brain and spinal cord pathological processes contributing to the slow loss of neurological function. This should also be complemented with a holistic approach to the management of other systemic disease processes that have been shown to worsen MS outcomes.

Efficacy and safety of plasma exchange or immunoadsorption for the treatment of option neuritis in demyelinating diseases: A systematic review and meta-analysis

BACKGROUND

There are no systematic reviews yet that evaluated the effects of PE/IA in patients with optic neuritis (ON) in demyelinating diseases. A meta-analysis of available study is needed to further explore the value of plasma exchange (PE) or immunoadsorption (IA) in treating ON in demyelinating diseases.

METHODS

All relevant articles published on PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), VIP Database, Wanfang, Sinomed and ophthalmology professional websites were searched. Study characteristics, demographic characteristics, clinical features and outcome measures were extracted. Response rate, adverse events (AE) rate, serious adverse event (SAE) rate, the log of the minimum angle of resolution (logMAR), visual outcome scale (VOS) and expanded disability status scales (EDSS) were evaluated using a random-effects model.

RESULTS

35 studies were included between 1985 and 2020, containing 1191 patients. The response rates of PE and IA in acute attack of ON were 68% and 82% respectively. LogMAR (-0.60 to - 1.42) and VOS (-1.10 to -1.82) had been significantly improved from within 1 month to more than 1 month after PE treatment. Besides, we found that logMAR improved 1.78, 0.95 and 0.38, respectively ,when the time from symptom onset to the first PE/IA was less than 21 days, 21-28 days, and more than 28 days. The pooled mean difference of EDSS was -1.14.Adverse effects rate in patients with PE or IA were 0.20 and 0.06, respectively.

CONCLUSION

The meta-analysis provided evidence that PE/IA treatment was an effective and safe intervention, and it is recommended that early initiation of PE/IA treatment is critical.

Charting a global research strategy for progressive MS-An international progressive MS Alliance proposal

BACKGROUND

Progressive forms of multiple sclerosis (MS) affect more than 1 million individuals globally. Recent approvals of ocrelizumab for primary progressive MS and siponimod for active secondary progressive MS have opened the therapeutic door, though results from early trials of neuroprotective agents have been mixed. The recent introduction of the term 'active' secondary progressive MS into the therapeutic lexicon has introduced potential confusion to disease description and thereby clinical management.

OBJECTIVE

This paper reviews recent progress, highlights continued knowledge and proposes, on behalf of the International Progressive MS Alliance, a global research strategy for progressive MS.

METHODS

Literature searches of PubMed between 2015 and May, 2021 were conducted using the search terms "progressive multiple sclerosis", "primary progressive multiple sclerosis", "secondary progressive MS". Proposed strategies were developed through a series of in-person and virtual meetings of the International Progressive MS Alliance Scientific Steering Committee.

RESULTS

Sustaining and accelerating progress will require greater understanding of underlying mechanisms, identification of potential therapeutic targets, biomarker discovery and validation, and conduct of clinical trials with improved trial design. Encouraging developments in symptomatic and rehabilitative interventions are starting to address ongoing challenges experienced by people with progressive MS.

CONCLUSION

We need to manage these challenges and realise the opportunities in the context of a global research strategy, which will improve quality of life for people with progressive MS.

Serum Neurofilament Light Association With Progression in Natalizumab-Treated Patients With Relapsing-Remitting Multiple Sclerosis

BACKGROUND AND OBJECTIVES

To investigate the potential of serum neurofilament light (NfL) to reflect or predict progression mostly independent of acute inflammatory disease activity in patients with relapsing-remitting multiple sclerosis (RRMS) treated with natalizumab.

METHODS

Patients were selected from a prospective observational cohort study initiated in 2006 at the VU University Medical Center Amsterdam, the Netherlands, including patients with RRMS treated with natalizumab. Selection criteria included an age of 18 years or older and a minimum follow-up of 3 years from natalizumab initiation. Clinical and MRI assessments were performed on a yearly basis, and serum NfL was measured at 5 time points during the follow-up, including on the day of natalizumab initiation (baseline), 3 months, 1 year, and 2 years after natalizumab initiation, and on last follow-up visit. Using general linear regression models, we compared the longitudinal dynamics of NfL between patients with and without confirmed Expanded Disability Status Scale (EDSS) progression between year 1 visit and last follow-up, and between individuals with and without EDSS⁺ progression, a composite endpoint including the EDSS, 9-hole peg test, and timed 25-foot walk.

RESULTS

Eighty-nine natalizumab-treated patients with RRMS were included. Median follow-up time was 5.2 years (interquartile range [IQR] 4.3-6.7, range 3.0-11.0) after natalizumab initiation, mean age at time of natalizumab initiation was 36.9 years (SD 8.5), and median disease duration was 7.4 years (IQR 3.8-12.1). Between year 1 and the last follow-up, 28/89 (31.5%) individuals showed confirmed EDSS progression. Data for the EDSS⁺ endpoint was available for 73 out of the 89 patients and 35/73 (47.9%) showed confirmed EDSS⁺ progression. We observed a significant reduction in NfL levels 3 months after natalizumab initiation, which reached its nadir of close to 50% of baseline levels 1 year after treatment initiation. We found no difference in the longitudinal dynamics of NfL in progressors vs nonprogressors. NfL levels at baseline and 1 year after natalizumab initiation did not predict progression at last follow-up.

CONCLUSION

In our cohort of natalizumab-treated patients with RRMS, NfL fails to capture or predict progression that occurs largely independently of clinical or radiologic signs of acute focal inflammatory disease activity. Additional biomarkers may thus be needed to monitor progression in these patients.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that serum NfL levels are not associated with disease progression in natalizumab-treated patients with RRMS.

Digital Endpoints: Definition, Benefits, and Current Barriers in Accelerating Development and Adoption

The assessment of health and disease requires a set of criteria to define health status and progression. These health measures are referred to as "endpoints." A "digital endpoint" is defined by its use of sensor-generated data often collected outside of a clinical setting such as in a patient's free-living environment. Applicable sensors exist in an array of devices and can be applied in a diverse set of contexts. For example, a smartphone's microphone might be used to diagnose or predict mild cognitive impairment due to Alzheimer's disease or a wrist-worn activity monitor (such as those found in smartwatches) may be used to measure a drug's effect on the nocturnal activity of patients with sickle cell disease. Digital endpoints are generating considerable excitement because they permit a more authentic assessment of the patient's experience, reveal formerly untold realities of disease burden, and can cut drug discovery costs in half. However, before these benefits can be realized, effort must be applied not only to the technical creation of digital endpoints but also to the environment that allows for their development and application. The future of digital endpoints rests on meaningful interdisciplinary collaboration, sufficient evidence that digital endpoints can realize their promise, and the development of an ecosystem in which the vast quantities of data that digital endpoints generate can be analyzed. The fundamental nature of health care is changing. With coronavirus disease 2019 serving as a catalyst, there has been a rapid expansion of home care models, telehealth, and remote patient monitoring. The increasing adoption of these health-care innovations will expedite the requirement for a digital characterization of clinical status as current assessment tools often rely upon direct interaction with patients and thus are not fit for purpose to be administered remotely. With the ubiquity of relatively inexpensive sensors, digital endpoints are positioned to drive this consequential change. It is therefore not surprising that regulators, physicians, researchers, and consultants have each offered their assessment of these novel tools. However, as we further describe later, the broad adoption of digital endpoints will require a cooperative effort. In this article, we present an analysis of the current state of digital endpoints. We also attempt to unify the perspectives of the parties involved in the development and deployment of these tools. We conclude with an interdependent list of challenges that must be collaboratively addressed before these endpoints are widely adopted.

Walking on common ground: a cross-disciplinary scoping review on the clinical utility of digital mobility outcomes

Physical mobility is essential to health, and patients often rate it as a high-priority clinical outcome. Digital mobility outcomes (DMOs), such as real-world gait speed or step count, show promise as clinical measures in many medical conditions. However, current research is nascent and fragmented by discipline. This scoping review maps existing evidence on the clinical utility of DMOs, identifying commonalities across traditional disciplinary divides. In November 2019, 11 databases were searched for records investigating the validity and responsiveness of 34 DMOs in four diverse medical conditions (Parkinson's disease, multiple sclerosis, chronic obstructive pulmonary disease, hip fracture). Searches yielded 19,672 unique records. After screening, 855 records representing 775 studies were included and charted in systematic maps. Studies frequently investigated gait speed (70.4% of studies), step length (30.7%), cadence (21.4%), and daily step count (20.7%). They studied differences between healthy and pathological gait (36.4%), associations between DMOs and clinical measures (48.8%) or outcomes (4.3%), and responsiveness to interventions (26.8%). Gait speed, step length, cadence, step time and step count exhibited consistent evidence of validity and responsiveness in multiple conditions, although the evidence was inconsistent or lacking for other DMOs. If DMOs are to be adopted as mainstream tools, further work is needed to establish their predictive validity, responsiveness, and ecological validity. Cross-disciplinary efforts to align methodology and validate DMOs may facilitate their adoption into clinical practice.

Clinical and Paraclinical Biomarkers and the Hitches to Assess Conversion to Secondary Progressive Multiple Sclerosis: A Systematic Review

Conversion to secondary progressive (SP) course is the decisive factor for long-term prognosis in relapsing multiple sclerosis (MS), generally considered the clinical equivalent of progressive MS-associated neuroaxonal degeneration. Evidence is accumulating that both inflammation and neurodegeneration are present along a continuum of pathologic processes in all phases of MS. While inflammation is the prominent feature in early stages, its quality changes and relative importance to disease course decreases while neurodegenerative processes prevail with ongoing disease. Consequently, anti-inflammatory disease-modifying therapies successfully used in relapsing MS are ineffective in SPMS, whereas specific treatment for the latter is increasingly a focus of MS research. Therefore, the prevention, but also the (anticipatory) diagnosis of SPMS, is of crucial importance. The problem is that currently SPMS diagnosis is exclusively based on retrospectively assessing the increase of overt physical disability usually over the past 6–12 months. This inevitably results in a delay of diagnosis of up to 3 years resulting in periods of uncertainty and, thus, making early therapy adaptation to prevent SPMS conversion impossible. Hence, there is an urgent need for reliable and objective biomarkers to prospectively predict and define SPMS conversion. Here, we review current evidence on clinical parameters, magnetic resonance imaging and optical coherence tomography measures, and serum and cerebrospinal fluid biomarkers in the context of MS-associated neurodegeneration and SPMS conversion. Ultimately, we discuss the necessity of multimodal approaches in order to approach objective definition and prediction of conversion to SPMS.

Measuring Treatment Response in Progressive Multiple Sclerosis-Considerations for Adapting to an Era of Multiple Treatment Options

Disability in multiple sclerosis accrues predominantly in the progressive forms of the disease. While disease-modifying treatment of relapsing MS has drastically evolved over the last quarter-century, the development of efficient drugs for preventing or at least delaying disability in progressive MS has proven more challenging. In that way, many drugs (especially disease-modifying treatments) have been researched in the aspect of delaying disability progression in patients with a progressive course of the disease. While there are some disease-modifying treatments approved for progressive multiple sclerosis, their effect is moderate and limited mostly to patients with clinical and/or radiological signs of disease activity. Several phase III trials have used different primary outcomes with different time frames to define disease progression and to evaluate the efficacy of a disease-modifying treatment. The lack of sufficiently sensitive outcome measures could be a possible explanation for the negative clinical trials in progressive multiple sclerosis. On the other hand, even with a potential outcome measure that would be sensitive enough to determine disease progression and, thus, the efficacy or failure of a disease-modifying treatment, the question of clinical relevance remains unanswered. In this systematic review, we analyzed outcome measures and definitions of disease progression in phase III clinical trials in primary and secondary progressive multiple sclerosis. We discuss advantages and disadvantages of clinical and paraclinical outcome measures aiming for practical ways of combining them to detect disability progression more sensitively both in future clinical trials and current clinical routine.

The use of multi-domain patient reported outcome measures for detecting clinical disease progression in multiple sclerosis

OBJECTIVE

Patient reported outcome measures (PROMs) are especially relevant in times of increased interest in telehealth but little is known about their relation to functional disability measures.

METHODS

We assessed 248 people with MS at baseline and at > = 5-years follow-up. We investigated cross-sectional and longitudinal correlations between changes in the Guy's Neurological disability scale (GNDS), and the physical part of the Multiple Sclerosis Impact Scale (MSIS-29) and the Expanded Disability Status Scale (EDSS), 9-hole peg test (9-HPT) and timed 25-foot walk (T25FW).

RESULTS

The strongest cross-sectional correlations were found between the GNDS and EDSS in the complete cohort (r = 0.66, p <.001, n = 248) as well as in progressive patients (r = 0.72, p <.001, n = 35), and the GNDS and T25FW in progressive MS (r = 0.64, p <.001, n = 34). Longitudinal correlations were poor except for changes on the leg domain of the GNDS in relation to T25FW changes in progressive MS (r = 0.68, p <.001, n = 26). In the majority of cases a clinically significant deterioration on the EDSS also resulted in a clinically significant worsening of the GDNS and MSIS.

CONCLUSION

Both PROMs correlate well with physical disability outcomes, and seem suitable for detecting changes in lower limb function in progressive MS. The GNDS has a higher agreement with EDSS progression than the MSIS-physical.

A Descriptive Correlational Study to Evaluate Three Measures of Assessing Upper Extremity Function in Individuals with Multiple Sclerosis

BACKGROUND

Activities of daily living and quality of life (QOL) are hindered by upper extremity (UE) impairments experienced by individuals with multiple sclerosis (iMS). The Nine-Hole Peg Test (9-HPT) is most frequently used to measure UE function. However, it does not measure peoples' ability to perform routine tasks in daily life and may not be useful in iMS who cannot pick up the pegs utilized in the 9-HPT. Therefore, we evaluated three measures to explore a more comprehensive assessment of UE function: Upper Extremity Function Scale (UEFS), Action Research Arm Test (ARAT), and the 9-HPT. The objectives were to quantitatively assess the relationship between these measures of UE function, understand if the measures correlate with QOL as calculated by the MS Quality of Life-54 (MSQOL-54), and to determine differences in the measures based on employment status.

METHODS

112 (79 female) iMS were prospectively recruited for this descriptive correlational study. Inclusion criteria were as follows: confirmed diagnosis of MS or clinically isolated syndrome, age ≥ 18 years, and ability to self-consent. All statistical analyses including Spearman's correlation coefficient (r s ) and Kruskal-Wallis tests were performed using SPSS.

RESULTS

A moderate correlation (r s = -0.51; p < 0.001) was found between the ARAT and 9-HPT scores for the more impaired hand. Likewise, a moderate correlation was found between UEFS and the physical health composite scores (PHCSs) of MSQOL-54 (r s = -0.59; p < 0.001). Finally, performances on ARAT, 9-HPT, and UEFS differed between the employed individuals and those on long-term disability (p = 0.007, p < 0.001, and p = 0.001).

CONCLUSION

The UEFS moderately correlated with the QOL measure, and considering the UESF is a patient-reported outcome, it could be used to complement routinely captured measures of assessing UE function. Further study is warranted to determine which measure, or combination of measures, is more sensitive to changes in UE function over time.

A matter of atrophy: differential impact of brain and spine damage on disability worsening in multiple sclerosis

As atrophy represents the most relevant driver of progression in multiple sclerosis (MS), we investigated the impact of different patterns of brain and spinal cord atrophy on disability worsening in MS. We acquired clinical and MRI data from 90 patients with relapsing–remitting MS and 24 healthy controls (HC). Clinical progression at follow-up (mean 3.7 years) was defined according to the Expanded Disability Status Scale-Plus. Brain and spinal cord volumes were computed on MRI brain scans. After normalizing each participants’ brain and spine volume to the mean of the HC, z-score cut-offs were applied to separate pathologically atrophic from normal brain and spine volumes (accepting a 2.5% error probability). Accordingly, MS patients were classified into four groups (Group I: no brain or spinal cord atrophy N = 40, Group II: brain atrophy/no spinal cord atrophy N = 11, Group III: no brain atrophy/ spinal cord atrophy N = 32, Group IV: both brain and spinal cord atrophy N = 7). All patients’ groups showed significantly lower brain volume than HC (p < 0.0001). Group III and IV showed lower spine volume than HC (p < 0.0001 for both). Higher brain lesion load was identified in Group II (p = 0.049) and Group IV (p = 0.023) vs Group I, and in Group IV (p = 0.048) vs Group III. Spinal cord atrophy (OR = 3.75, p = 0.018) and brain + spinal cord atrophy (OR = 5.71, p = 0.046) were significant predictors of disability progression. The presence of concomitant brain and spinal cord atrophy is the strongest correlate of progression over time. Isolated spinal cord atrophy exerts a similar effect, confirming the leading role of spinal cord atrophy in the determination of motor disability.

Deciphering Multiple Sclerosis Progression

Multiple sclerosis (MS) is primarily an inflammatory and degenerative disease of the central nervous system, triggered by unknown environmental factors in patients with predisposing genetic risk profiles. The prevention of neurological disability is one of the essential goals to be achieved in a patient with MS. However, the pathogenic mechanisms driving the progressive phase of the disease remain unknown. It was described that the pathophysiological mechanisms associated with disease progression are present from disease onset. In daily practice, there is a lack of clinical, radiological, or biological markers that favor an early detection of the disease's progression. Different definitions of disability progression were used in clinical trials. According to the most descriptive, progression was defined as a minimum increase in the Expanded Disability Status Scale (EDSS) of 1.5, 1.0, or 0.5 from a baseline level of 0, 1.0–5.0, and 5.5, respectively. Nevertheless, the EDSS is not the most sensitive scale to assess progression, and there is no consensus regarding any specific diagnostic criteria for disability progression. This review document discusses the current pathophysiological concepts associated with MS progression, the different measurement strategies, the biomarkers associated with disability progression, and the available pharmacologic therapeutic approaches.

Contribution of Relapse-Independent Progression vs Relapse-Associated Worsening to Overall Confirmed Disability Accumulation in Typical Relapsing Multiple Sclerosis in a Pooled Analysis of 2 Randomized Clinical Trials

Question

What are the relative contributions of progression independent of relapse activity (PIRA) and relapse-associated worsening (RAW) to overall accumulating disability in patients with relapsing multiple sclerosis?

Findings

Applying a composite outcome measure to a typical population with active relapsing multiple sclerosis, this pooled analysis of 2 randomized clinical trials shows that the most part of confirmed disability accumulation occurs independently of relapse activity. Distinct prognostic factors were associated with PIRA vs RAW, and ocrelizumab had a beneficial outcome in both.

Meaning

These findings clearly demonstrate underlying progression in this relapsing multiple sclerosis population and challenge the current clinical distinction of relapsing and progressive forms of multiple sclerosis.

Importance

Accumulation of disability in multiple sclerosis may occur as relapse-associated worsening (RAW) or steady progression independent of relapse activity (PIRA), with PIRA regarded as a feature of primary and secondary progressive multiple sclerosis.

Objective

To investigate the contributions of relapse-associated worsening vs relapse-independent progression to overall confirmed disability accumulation (CDA) and assess respective baseline prognostic factors and outcomes of 2 treatments.

Design, Setting, and Participants

Analyses occurred from July 2015 to February 2020 on pooled data from the intention-to-treat population of 2 identical, phase 3, multicenter, double-blind, double-dummy, parallel-group randomized clinical trials (OPERA I and II) conducted between August 2011 and April 2015. In the trials, patients with relapsing multiple sclerosis (RMS), diagnosed using the 2010 revised McDonald criteria, were randomized from 307 trial sites in 56 countries; resulting data were analyzed in the pooled data set.

Interventions

Participants were randomized 1:1 to receive 600 mg of ocrelizumab by intravenous infusion every 24 weeks or subcutaneous interferon β-1a 3 times a week at a dose of 44 μg throughout a 96-week treatment period.

Main Outcomes and Measures

Confirmed disability accumulation was defined by an increase in 1 or more of 3 measures (Expanded Disability Status Scale, timed 25-ft walk, or 9-hole peg test), confirmed after 3 or 6 months, and classified per temporal association with confirmed clinical relapses (PIRA or RAW).

Results

In the pooled OPERA I and II population (1656 of 2096 eligible participants), baseline demographics and disease characteristics were similar for patients randomized to interferon β-1a vs ocrelizumab (mean [SD] age, 37.2 [9.2] vs 37.1 [9.2] years; 552 [66.6%] vs 541 women [65.4%]). After 96 weeks, 12-week composite CDA had occurred in 223 (29.6% by Kaplan-Meier estimate) randomized to interferon β-1a and 167 (21.1%) randomized to ocrelizumab; 24-week composite CDA had occurred in 170 (22.7%) taking interferon β-1a and 129 (16.2%) taking ocrelizumab. The PIRA events were the main contributors to 12-week and 24-week composite CDA after 96 weeks in patients treated with interferon β-1a (174 of 223 [78.0%] and 137 of 170 [80.6%], respectively) and ocrelizumab (147 of 167 [88.0%] and 115 of 129 [89.1%], respectively); a minority had CDA explained by RAW events (69 of 390 [17.7%] and 52 of 299 [17.4%], respectively). Very few patients with composite CDA experienced both RAW and PIRA events (17 of 390 [4.4%] for 12-week and 15 of 299 [5.0%] for 24-week composite CDA). Ocrelizumab (vs interferon β-1a) was associated with reduced risk of composite CDA (hazard ratio [HR], 0.67) and confirmed PIRA (HR, 0.78) and RAW (HR, 0.47) events.

Conclusions and Relevance

Most disability accumulation in RMS is not associated with overt relapses. This indicates an underlying progression in this typical RMS population and challenges the current clinical distinction of relapsing and progressive forms of multiple sclerosis. Ocrelizumab was superior to interferon β-1a in preventing both RAW and PIRA.

Trial Registration

ClinicalTrials.gov Identifiers: OPERA I (NCT01247324) and OPERA II (NCT01412333).

Diagnosis of Progressive Multiple Sclerosis From the Imaging Perspective: A Review

Importance

Although magnetic resonance imaging (MRI) is useful for monitoring disease dissemination in space and over time and excluding multiple sclerosis (MS) mimics, there has been less application of MRI to progressive MS, including diagnosing primary progressive (PP) MS and identifying patients with relapsing-remitting (RR) MS who are at risk of developing secondary progressive (SP) MS. This review addresses clinical application of MRI for both diagnosis and prognosis of progressive MS.

Observations

Although nonspecific, some spinal cord imaging features (diffuse abnormalities and lesions involving gray matter [GM] and ≥2 white matter columns) are typical of PPMS. In patients with PPMS and those with relapse-onset MS, location of lesions in critical central nervous system regions (spinal cord, infratentorial regions, and GM) and MRI-detected high inflammatory activity in the first years after diagnosis are risk factors for long-term disability and future progressive disease course. These measures are evaluable in clinical practice. In patients with established MS, GM involvement and neurodegeneration are associated with accelerated clinical worsening. Subpial demyelination and slowly expanding lesions are novel indicators of progressive MS.

Conclusions and Relevance

Diagnosis of PPMS is more challenging than diagnosis of RRMS. No qualitative clinical, immunological, histopathological, or neuroimaging features differentiate PPMS and SPMS; both are characterized by imaging findings reflecting neurodegeneration and are also impacted by aging and comorbidities. Unmet diagnostic needs include identification of MRI markers capable of distinguishing PPMS from RRMS and predicting the evolution of RRMS to SPMS. Integration of multiple parameters will likely be essential to achieve these aims.

Should We Use Clinical Tools to Identify Disease Progression?

The presence of disability progression in multiple sclerosis (MS) is an important hallmark for MS patients in the course of their disease. The transition from relapsing remitting (RRMS) to secondary progressive forms of the disease (SPMS) represents a significant change in their quality of life and perception of the disease. It could also be a therapeutic key for opportunities, where approaches different from those in the initial phases of the disease can be adopted. The characterization of structural biomarkers (e.g., magnetic resonance imaging or neurofilament light chain) has been proposed to differentiate between both phenotypes. However, there is no definite threshold between them. Whether the risk of clinical progression can be predicted by structural markers at early disease phases is still a focus of clinical research. However, several theories and pathological evidence suggest that both disease phenotypes are part of a continuum with common pathophysiological mechanisms. In this case, the clinical evaluation of the patients would play a preponderant role above destruction biomarkers for the early identification of disability progression and SPMS. For this purpose, the use of clinical tools beyond the Expanded Disability Status Scale (EDSS) should be considered. Besides established functional tests such as the Multiple Sclerosis Functional Composite (MSFC), patient's neurological history or digital resources may help neurologists in the decision-taking. In this article, we discuss arguments for the use of clinical markers in the detection of secondary progressive MS and the characterization of progressive disease activity.