Relapse-independent multiple sclerosis progression under natalizumab

Suboptimal B-cell depletion is associated with progression independent of relapse activity in multiple sclerosis patients treated with ocrelizumab

BACKGROUND

While treatment with ocrelizumab has proven effective in preventing relapse-associated worsening (RAW) in relapsing multiple sclerosis (RMS), a significant number of patients experience progression independent of relapse activity (PIRA).

OBJECTIVES

To investigate the association between B-cell depletion status and the risk of disability accumulation in RMS patients receiving ocrelizumab treatment.

METHODS

In this monocentric cohort study of 148 RMS patients (2017-2023), we categorized participants into three groups: no evidence of disease activity (NEDA), evidence of disease activity (EDA), and PIRA. B-cell counts were measured every 6-12 months, with suboptimal depletion defined as ⩾10 CD19+ B-cells/µL. Logistic regression and Cox proportional hazards models analyzed the relationship between B-cell depletion and disability progression.

RESULTS

Of 148 patients, 70 (47%) achieved NEDA, 51 (34%) showed EDA, and 25 (17%) developed PIRA. NEDA patients demonstrated significantly lower B-cell counts compared to EDA (p < 0.01) and PIRA (p < 0.001) groups. Insufficient B-cell depletion was the strongest PIRA predictor (OR 3.73, 95% CI: 2.50-5.43, p < 0.001) and increased EDSS progression risk (HR 0.50, 95% CI: 0.26-0.97, p = 0.039).

CONCLUSIONS

PIRA occurs in the context of suboptimal B-cell depletion in RMS patients, highlighting the need for close monitoring and potential adjustment of infusion intervals.

Quality of life is decreased in persons with relapsing-remitting multiple sclerosis experiencing progression independent of relapse activity

INTRODUCTION

Reduced quality of life (QoL) is an early feature of multiple sclerosis (MS). The effect of progression independent of relapse activity (PIRA) on QoL is poorly investigated.

OBJECTIVE

To assess the impact of PIRA on QoL using patient-reported outcome measures (PROMs).

METHODS

In a prospective observational study, 125 newly diagnosed persons with relapsing-remitting MS (PwRRMS) were assessed over 5 years with: EuroQoL-5-Dimension-3-level (EQ-5D-3L), EQ-visual-analogous-scale (EQ-VAS) and 29-item-MS-Impact-Scale (MSIS-29). PwRRMS were dichotomized: PIRA (worsening of expanded disability status scale (EDSS), timed-25-foot-walk or 9-hole-peg-test, independent of relapses) versus non-PIRA. PwRRMS were compared at baseline, year 5 (y5) and delta values (baseline scores subtracted from y5 scores) and annually using linear-mixed-effects-models.

RESULTS

At y5, 19.2% had PIRA. PIRA versus non-PIRA PwRRMS were older (p < 0.001). At y5 PIRA PwRRMS had lower EQ-5D-3L (p = 0.001), higher MSIS-29-PHYS (p < 0.001), delta values showed lower EQ-5D-3L (p < 0.001) and EQ-VAS (p = 0.010), higher MSIS-29-PHYS (p = 0.004) and MSIS-29-PSYCH (p = 0.036). Linear-mixed-effects-models showed that, compared to PIRA, non-PIRA PwRRMS had an improvement in QoL: EQ-5D-3L: β = 0.039, p < 0.001; EQ-VAS: β = 2.401, p < 0.001; MSIS-29-PHYS: β = -0.107, p < 0.001; MSIS-29-PSYCH, β = -0.115, p < 0.001, during the 5-year study period.

CONCLUSION

Deteriorating QoL in the early course of relapsing-remitting multiple sclerosis (RRMS) is strongly associated with PIRA. Our results suggest that QoL PROMs should be monitored and recognized as an important aspect of progression.

Cervical spinal cord gray matter damage predicts disability worsening in multiple sclerosis: a longitudinal study

OBJECTIVE

Cervical spinal cord (cSC) gray matter (GM) damage is associated with current disability in multiple sclerosis (MS), but its prognostic value remains unexplored. We aimed to investigate whether cSC GM damage may predict disability worsening in MS.

MATERIALS AND METHODS

Seventy-nine MS patients and 49 healthy controls (HC) underwent 3 T brain and cSC MRI at baseline and two neurological evaluations after median follow-up of 1.3 years. Total and GM cSC lesions were identified on axial T2-weighted sequences, whereas global and GM cSC cross-sectional areas (CSAs) at C3-C4 level were quantified on phase-sensitive inversion recovery sequences. Brain lesional and volumetric measures were also assessed. At follow-up, disability worsening was defined as deterioration on ≥ 1/3 components of the Expanded Disability Status Scale (EDSS)-plus score (EDSS worsening or ≥ 20% change in timed 25-foot walk [T25FWT] or 9-hole peg test [9-HPT]).

RESULTS

At follow-up, 40/79 (50.6%) patients showed EDSS-plus worsening, with 13/79 (16.4%) worsening at EDSS score, 13/79 (16.4%) at 9-HPT, and 29/79 (36.7%) at T25FWT. Progressive phenotype (odds ratio [OR] = 8.65) predicted EDSS worsening (p = 0.001, C-index = 0.79). Progressive phenotype (OR = 5.56), lower cortical volume (OR = 0.41), and higher cSC GM T2-hyperintense lesion volume (OR = 2.28) (p ≤ 0.035, C-index = 0.88) predicted 9-HPT worsening. Longer disease duration (OR = 1.64), progressive phenotype (OR = 4.74), and lower cSC GM CSA (OR = 0.51) predicted T25FWT worsening (p ≤ 0.050, C-index = 0.77). Male sex (OR = 6.12), older age (OR = 1.71), progressive phenotype (OR = 7.40), and lower cSC GM CSA (OR = 0.47) predicted EDSS-plus worsening (p ≤ 0.055, C-index = 0.83).

CONCLUSIONS

cSC GM damage emerged as a relevant MRI predictor of disability worsening in MS, highlighting its prognostic relevance.

Towards a biological view of multiple sclerosis from early subtle to clinical progression: an expert opinion

The classification of multiple sclerosis (MS) into the two distinct phases of relapsing-remitting and progressive, including primary progressive and secondary progressive phenotypes (PPMS and SPMS, respectively) has long been accepted; however, there are several unmet needs associated with this particular model. The observation that both inflammation and neurodegeneration are present from the onset of MS has resulted in a paradigm shift towards MS as a disease continuum driven by pathological mechanisms underlying clinical progression. Here we report the results from a meeting of Italian MS specialists, exploring the evolving perception of MS pathobiology and its implications for diagnosis and treatment. Insights garnered from the expert panel advocate for a redefined understanding of MS. This expert opinion paper reviews the disease continuum and the intertwined nature of inflammatory and neurodegenerative processes. Also, the need for changes in diagnostic criteria and treatment strategies, including the development of novel biomarkers and new therapies targeting smouldering disease, is discussed.

A Window into New Insights on Progression Independent of Relapse Activity in Multiple Sclerosis: Role of Therapies and Current Perspective

In multiple sclerosis (MS), there is significant evidence indicating that both progression independent of relapse activity (PIRA) and relapse-related worsening events contribute to the accumulation of progressive disability from the onset of the disease and throughout its course. Understanding the compartmentalized pathophysiology of MS would enhance comprehension of disease progression mechanisms, overcoming the traditional distinction in phenotypes. Smoldering MS activity is thought to be maintained by a continuous interaction between the parenchymal chronic processes of neuroinflammation and neurodegeneration and the intrathecal compartment. This review provides a comprehensive and up-to-date overview of the neuropathological and immunological evidence related to the mechanisms underlying PIRA phenomena in MS, with a focus on studies investigating the impact of currently available therapies on these complex mechanisms.

MRI versus relapse: optimal activity monitoring for management of progressive multiple sclerosis

Secondary progressive multiple sclerosis is often categorized as 'active'/'non-active' based on inflammatory activity on MRI, or relapse; however, the value of MRI/relapse as indicators of disease activity in real-world and clinical trial settings merits further investigation. We separately analysed retrospective data from patients with clinically diagnosed secondary progressive multiple sclerosis in the Adelphi Real-World Disease Specific Programme (a cross-sectional survey) in multiple sclerosis (Adelphi: n = 2554) and the placebo group of the Phase III EXploring the efficacy and safety of siponimod in PAtients with secoNDary progressive multiple sclerosis (EXPAND) trial, [EXPAND-PBO (placebo group of the EXPAND): n = 546] to assess: differences between active/non-active disease in the real-world (characteristics; monitoring); the value of MRI and relapse to indicate disease activity; and the number and characteristics of non-active patients with disease activity in the clinical study. In Adelphi, 1889 patients had 'active' disease (≥1 relapse in the year before index date and/or ≥1 new lesion on most recent MRI) versus 665 with 'non-active' disease (no relapses in the previous year and no new lesions on MRI); median age was 48 versus 53 years; 73.5 versus 87.8% had moderate-to-severe disease; 75.7 versus 54.3% were taking disease-modifying treatment; 87.7 versus 58.7% had received an MRI in the past year. Most active cases (n = 1116; 59.1%) were identified by MRI versus 239 (12.7%) by relapse and 534 (28.3%) by MRI plus relapse. In EXPAND-PBO, 263 patients were classified 'active' (≥1 relapse in 2 years before screening and/or ≥1 gadolinium-enhancing lesion) and 270 'non-active' (no relapse in the 2 years before screening and no gadolinium-enhancing lesion[s]) at baseline; similar proportions of these groups had received disease-modifying treatment prior to placebo: 77.2 and 80.7%. Of non-active patients, 53.0% had disease activity on study; in these patients, 74.1% had disease activity identified by MRI, 8.4% by relapse, and 17.5% by MRI plus relapse. In patients classified non-active at baseline: age and percentage with Expanded Disability Status Scale score 6.0-6.5 were similar between patients with disease activity on study versus patients who remained non-active: 48 versus 52 years; 49.7 versus 56.7%, respectively. In real-world and clinical trial settings, MRI could be a better option than relapse for the identification of disease activity. However, in the real-world, fewer non-active patients had received an MRI in the last year than active patients, which is concerning given that most disease activity in EXPAND-PBO was identified via MRI. We highlight difficulties in consistently identifying disease activity and the negative implications of infrequent monitoring of non-active disease.

Multiple sclerosis: emerging epidemiological trends and redefining the clinical course

Multiple sclerosis is a chronic, inflammatory, and neurodegenerative disease of the central nervous system and a major cause of neurological disability in young adults. Its prevalence and incidence are increasing, and it has been estimated at over 2.8 million cases worldwide, in addition to recent trends towards a shift in MS prevalence to older ages, with peak prevalence estimates in the sixth decade of life. Although historically the relapsing and progressive phases of the disease have been considered separate clinical entities, recent evidence of progression independent of relapse activity (PIRA) has led to a reconsideration of multiple sclerosis as a continuum, in which relapsing and progressive features variably coexist from the earliest stages of the disease, challenging the traditional view of the disease course. In this Series article, we provide an overview of how the traditional description of the clinical course of MS and epidemiological trends in Europe have evolved. For this purpose, we focus on the concept of PIRA, discussing its potential as the main mechanism by which patients acquire disability, how its definition varies between studies, and ongoing research in this field. We emphasise the importance of incorporating the assessment of hidden clinical manifestations into patient management to help uncover and quantify the PIRA phenomenon and the possible implications for future changes in the clinical classification of the disease. At the same time, we provide insights into overcoming the challenges of identifying and defining PIRA and adopting a new understanding of the clinical course of MS.

Disability patterns in multiple sclerosis: A meta-analysis on RAW and PIRA in the real-world context

OBJECTIVE

To summarize the current evidence on relapse-associated worsening (RAW) and progression independent of relapse activity (PIRA) through a quantitative synthesis of real-world studies.

METHODS

Scientific databases were searched to identify suitable articles. Random-effects meta-analyses, subgroup analyses and meta-regression models were ran to provide pooled estimates of RAW and PIRA events and to identify their potential moderators (PROSPERO registration: CRD42024503895).

RESULTS

Eighteen articles met the eligibility criteria, with a pooled sample size of 52,667 patients (93% relapsing-remitting, 6% clinically isolated syndrome and 1% progressive) followed for 2.4 to 12.1 years, yielding to 415,825 patient-years. Pooled event rates for RAW and PIRA were 1.6 (95 confidence interval (CI) = 1.1-2.1) and 3.1 (95% CI = 2.3-3.9) per 100 patient-years, respectively. Less RAW events were found in cohorts including patients with progressive course (β = -0.069, p = 0.006) and under high-efficacy disease-modifying treatments (DMTs) (β = -0.031, p = 0.007), while PIRA events were directly related to older age (β = 0.397, p = 0.027). In addition, we found significant differences in PIRA event rates according to the criteria adopted to define confirmed disability accrual (p < 0.05).

DISCUSSION

PIRA accounts for most events causing disability accumulation in the real-world setting, even at the earlier disease stages, whereas RAW represents a less frequent phenomenon, likely due to effective treatments. The detection and statistical analysis of PIRA outcomes pose challenges, raising the risk of erroneous inference. When interpreting our findings, caution is needed given the wide heterogeneity of included studies.

The Faces of "Too Late"-A Surprisingly Progressive Cohort of "Stable" Relapsing Remitting Multiple Sclerosis Patients

Background and Objectives: Although available therapies have changed the natural evolution of multiple sclerosis (MS), in time some patients assume a progressive course and no longer respond to treatment. There is no definitive clinical or laboratory parameter to certify MS progression from relapsing remitting MS (RRMS) to secondary progressive MS (SPMS) in early phases of transition. Our study aims to evaluate the value of clinical parameters and serum neurofilament light chain levels (sNfLs) as early warning signs of conversion to SPMS. Materials and Methods: The Expanded Disability Status Scale (EDSS), Nine-Hole Peg Test (9HPT), 25-foot walk test (25FWT) and Symbol Digit Modalities Test (SDMT) were evaluated at 12 months apart in a cohort of 83 RRMS treated patients. sNfLs were evaluated at the second time point. Results: sNfLs correlate with EDSS and SDMT, with EDSS change and disease duration. Clinical parameters correlate among themselves and perform well in supporting the diagnosis of SPMS in logistic regression and ROC curves analysis. Eighty percent of the RRMS patients in our study (of which 65% are treated with high-efficacy disease-modifying drugs) showed some type of progression independent of relapses (PIRA) after 12 months, with one in five patients experiencing isolated cognitive worsening and almost two-thirds some type of motor worsening. We found no differences in terms of progression between patients treated with platform drugs versus high-efficacy drugs. Conclusions: An elevated level of progression independent of relapses (PIRA) was found in our cohort, with high-efficacy drugs providing no supplementary protection. As sNfL levels were correlated with the progression of EDSS (the main clinical progression marker), they may be considered potential prognostic markers, but further studies are necessary to precisely define their role in this direction. The lack of early sensitive markers for risk of progression may contribute to therapeutic delay and failure.

The contribution of tumor necrosis factor to multiple sclerosis: a possible role in progression independent of relapse?

Tumor necrosis factor (TNF) is a pleiotropic cytokine regulating many physiological and pathological immune-mediated processes. Specifically, it has been recognized as an essential pro-inflammatory cytokine implicated in multiple sclerosis (MS) pathogenesis and progression. MS is a chronic immune-mediated disease of the central nervous system, characterized by multifocal acute and chronic inflammatory demyelination in white and grey matter, along with neuroaxonal loss. A recent concept in the field of MS research is disability resulting from Progression Independent of Relapse Activity (PIRA). PIRA recognizes that disability accumulation since the early phase of the disease can occur independently of relapse activity overcoming the traditional dualistic view of MS as either a relapsing-inflammatory or a progressive-neurodegenerative disease. Several studies have demonstrated an upregulation in TNF expression in both acute and chronic active MS brain lesions. Additionally, elevated TNF levels have been observed in the serum and cerebrospinal fluid of MS patients. TNF appears to play a significant role in maintaining chronic intrathecal inflammation, promoting axonal damage neurodegeneration, and consequently contributing to disease progression and disability accumulation. In summary, this review highlights the current understanding of TNF and its receptors in MS progression, specifically focusing on the relatively unexplored PIRA condition. Further research in this area holds promise for potential therapeutic interventions targeting TNF to mitigate disability in MS patients.

New views on the complex interplay between degeneration and autoimmunity in multiple sclerosis

Multiple sclerosis (MS) is a frequently disabling neurological disorder characterized by symptoms, clinical signs and imaging abnormalities that typically fluctuate over time, affecting any level of the CNS. Prominent lymphocytic inflammation, many genetic susceptibility variants involving immune pathways, as well as potent responses of the neuroinflammatory component to immunomodulating drugs, have led to the natural conclusion that this disease is driven by a primary autoimmune process. In this Hypothesis and Theory article, we discuss emerging data that cast doubt on this assumption. After three decades of therapeutic experience, what has become clear is that potent immune modulators are highly effective at suppressing inflammatory relapses, yet exhibit very limited effects on the later progressive phase of MS. Moreover, neuropathological examination of MS tissue indicates that degeneration, CNS atrophy, and myelin loss are most prominent in the progressive stage, when lymphocytic inflammation paradoxically wanes. Finally, emerging clinical observations such as "progression independent of relapse activity" and "silent progression," now thought to take hold very early in the course, together argue that an underlying "cytodegenerative" process, likely targeting the myelinating unit, may in fact represent the most proximal step in a complex pathophysiological cascade exacerbated by an autoimmune inflammatory overlay. Parallels are drawn with more traditional neurodegenerative disorders, where a progressive proteopathy with prion-like propagation of toxic misfolded species is now known to play a key role. A potentially pivotal contribution of the Epstein-Barr virus and B cells in this process is also discussed.

Chemokine-mediated cell migration into the central nervous system in progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) has been associated with different forms of immune compromise. This study analyzes the chemokine signals and attracted immune cells in cerebrospinal fluid (CSF) during PML to define immune cell subpopulations relevant for the PML immune response. In addition to chemokines that indicate a general state of inflammation, like CCL5 and CXCL10, the CSF of PML patients specifically contains CCL2 and CCL4. Single-cell transcriptomics of CSF cells suggests an enrichment of distinct CD4+ and CD8+ T cells expressing chemokine receptors CCR2, CCR5, and CXCR3, in addition to ITGA4 and the genetic PML risk genes STXBP2 and LY9. This suggests that specific immune cell subpopulations migrate into the central nervous system to mitigate PML, and their absence might coincide with PML development. Monitoring them might hold clues for PML risk, and boosting their recruitment or function before therapeutic immune reconstitution might improve its risk-benefit ratio.

Risk of secondary progression in patients with highly active multiple sclerosis treated with natalizumab: a real-life study

BACKGROUND

one of the most important therapeutic goals in relapse-onset multiple sclerosis is to preclude conversion to secondary progression. Our objective was to determine the risk of progression associated with natalizumab treatment in an registry-based cohort of patients and to identify determinant factors.

METHODS

Patients with relapse-onset multiple sclerosis from the Registre Lorrain des Scléroses en Plaques (ReLSEP) were included if they had received one infusion of natalizumab between 2002 and 2021. The risk of secondary progression was determined using a standardized definition and a multi-state estimator to account for the possibility of stopping natalizumab before progression, and analyzed with multivariate Cox models.

RESULTS

574 patients were followed up for a median of 6.7 years. Of the 304 who stopped NTZ before progression onset, the probabilities (95% confidence interval) to convert to progression after 1, 2, 5 and 10 years were 3.2% (2.0-4.8%), 5.3% (3.6-7.3%), 17.5% (14.3-21.3%) and 28.3% (23.7-33.7%), respectively. Discontinuation of NTZ during follow-up was significantly associated with an increased risk of conversion in case of no resumption of a highly active treatment thereafter (adjusted hazard ratio = 2.7; 95% confidence interval 1.5-4.9; p = 0.001). The use of such a treatment was associated with a lower risk of progression (adjusted hazard ratio = 0.42; 95% confidence interval 0.23-0.79; p = 0.007).

CONCLUSION

the risk of conversion to secondary progression associated with natalizumab treatment is relatively low but increases in case of natalizumab discontinuation in the absence of switch to highly active immunosuppressant.

Autologous hematopoietic stem cell transplantation is superior to alemtuzumab in patients with highly active relapsing multiple sclerosis and severe disability

OBJECTIVE

To assess the differences of treatment outcomes regarding disease activity in patients with highly active relapsing multiple sclerosis (RMS), treated with autologous hematopoietic stem cell transplantation (HSCT) or alemtuzumab (ATZ).

METHODS

Open-label prospective single-center observational cohort study, enrolling patients with highly active RMS for treatment with ATZ or HSCT between 2014 and 2021.

RESULTS

A total of 50 patients (31/50 (62 %) in HSCT vs 19/50 (38 %) in ATZ group) were included. There were no significant differences in relapse rate, MRI activity or disability worsening between the two study groups during the first two years after treatment onset. However, at 3 to 5 years follow-up, HSCT was superior to ATZ in all the aforementioned aspects. Kaplan-Meier analysis at 5 years post treatment revealed superiority of HSCT in relapse rate (69.6 % vs 95.7 %, p = 0.027), MRI activity (54.5 % vs 75.1 %, p = 0.038) and disability worsening (57.1 % vs 90.9 %, p =  0.031).

CONCLUSIONS

ATZ may halt disability progression early in the course of highly active RMS, but the disability starts accumulating later, while in HSCT patients disability improvement is consistent both 3 and 5 years after treatment onset.

Harmonizing Definitions for Progression Independent of Relapse Activity in Multiple Sclerosis: A Systematic Review

Importance

Emerging evidence suggests that progression independent of relapse activity (PIRA) is a substantial contributor to long-term disability accumulation in relapsing-remitting multiple sclerosis (RRMS). To date, there is no uniform agreed-upon definition of PIRA, limiting the comparability of published studies.

Objective

To summarize the current evidence about PIRA based on a systematic review, to discuss the various terminologies used in the context of PIRA, and to propose a harmonized definition for PIRA for use in clinical practice and future trials.

Evidence Review

A literature search was conducted using the search terms multiple sclerosis, PIRA, progression independent of relapse activity, silent progression, and progression unrelated to relapses in PubMed, Embase, Cochrane, and Web of Science, published between January 1990 and December 2022.

Findings

Of 119 identified single records, 48 eligible studies were analyzed. PIRA was reported to occur in roughly 5% of all patients with RRMS per annum, causing at least 50% of all disability accrual events in typical RRMS. The proportion of PIRA vs relapse-associated worsening increased with age, longer disease duration, and, despite lower absolute event numbers, potent suppression of relapses by highly effective disease-modifying therapy. However, different studies used various definitions of PIRA, rendering the comparability of studies difficult.

Conclusion and Relevance

PIRA is the most frequent manifestation of disability accumulation across the full spectrum of traditional MS phenotypes, including clinically isolated syndrome and early RRMS. The harmonized definition suggested here may improve the comparability of results in current and future cohorts and data sets.

Should autologous hematopoietic stem cell transplantation be offered as a first-line disease modifying therapy to patients with multiple sclerosis?

In multiple sclerosis (MS), progression independent of new focal inflammation may commence shortly after disease onset, and it is increasingly revealed that the risk of disability accrual is reduced by early use of high-efficacy disease-modifying therapies (HE-DMTs). People with aggressive MS may therefore benefit from early treatment with autologous haematopoietic stem cell transplantation (AHSCT), a procedure inducing maximal immunosuppression followed by immune reconstitution, demonstrated to be superior to DMTs in one randomized clinical trial. However, in current practice prior failure to HE-DMTs is typically required to establish the indication for AHSCT. In the present article, the available evidence on the potential role of AHSCT as first-line treatment in aggressive MS and the rationale for its early use will be summarized. Proposed definitions of aggressive MS that could help identifying MS patients eligible for early treatment with AHSCT will also be discussed.

Defining progression independent of relapse activity (PIRA) in adult patients with relapsing multiple sclerosis: A systematic review✰

BACKGROUND

Progression Independent of Relapse Activity (PIRA) is heterogeneously described in patients with multiple sclerosis (MS) regarding the frequency and nature of PIRA. This systematic review was conducted to characterise and define the elements of PIRA.

METHOD

This systematic review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search was conducted of the databases Embase, Medline, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, ClinicalTrials.gov and Google Scholar.

RESULTS

5,812 studies were identified by the initial search. 13 studies satisfied the inclusion criteria and were included in the systematic review. PIRA definitions varied considerably between studies. In the context of these variable definitions, along with other methodological differences relating to disease modifying therapy (DMT) use and follow-up duration, the reported proportion of patients experiencing PIRA varied from 4% to 24%.

CONCLUSIONS

The currently available research supports the presence of PIRA in relapsing MS. Based on review of the existing literature, we propose a definition of PIRA that is clinically relevant and minimises confounding from inclusion of patients who have reached the secondary progressive phase of the disease.

Real-world evidence of ocrelizumab-treated relapsing multiple sclerosis cohort shows changes in progression independent of relapse activity mirroring phase 3 trials

Ocrelizumab is a B cell-depleting drug widely used in relapsing-remitting multiple sclerosis (RRMS) and primary-progressive MS. In RRMS, it is becoming increasingly apparent that accumulation of disability not only manifests as relapse-associated worsening (RAW) but also as progression independent of relapse activity (PIRA) throughout the disease course. This study's objective was to investigate the role of PIRA in RRMS patients treated with ocrelizumab. We performed a single-center, retrospective, cross-sectional study of clinical data acquired at a German tertiary multiple sclerosis referral center from 2018 to 2022. All patients with RRMS treated with ocrelizumab for at least six months and complete datasets were analyzed. Confirmed disability accumulation (CDA) was defined as a ≥ 12-week confirmed increase from the previous expanded disability status scale (EDSS) score of ≥ 1.0 if the previous EDSS was ≤  5.5 or a ≥ 0.5-point increase if the previous EDSS was > 5.5. PIRA was defined as CDA without relapse since the last EDSS measurement and at least for the preceding 12 weeks. RAW was defined as CDA in an interval of EDSS measurements with ≥ 1 relapses. Cox proportional hazard models were used to analyze the probability of developing PIRA depending on various factors, including disease duration, previous disease-modifying treatments (DMTs), and optical coherence tomography-assessed retinal degeneration parameters. 97 patients were included in the analysis. Mean follow-up time was 29 months (range 6 to 51 months). 23.5% developed CDA under ocrelizumab therapy (n = 23). Of those, the majority developed PIRA (87.0% of CDA, n = 20) rather than RAW (13.0% of CDA, n = 3). An exploratory investigation using Cox proportional hazards ratios revealed two possible factors associated with an increased probability of developing PIRA: a shorter disease duration prior to ocrelizumab (p = 0.02) and a lower number of previous DMTs prior to ocrelizumab (p = 0.04). Our data show that in ocrelizumab-treated RRMS patients, the main driver of disability accumulation is PIRA rather than RAW. Furthermore, these real-world data show remarkable consistency with data from phase 3 randomized controlled trials of ocrelizumab in RRMS, which may increase confidence in translating results from tightly controlled RCTs into the real-world clinical setting.

Serum glial fibrillary acidic protein in natalizumab-treated relapsing-remitting multiple sclerosis: An alternative to neurofilament light

BACKGROUND

There is a need in Relapsing-Remitting Multiple Sclerosis (RRMS) treatment for biomarkers that monitor neuroinflammation, neurodegeneration, treatment response, and disease progression despite treatment.

OBJECTIVE

To assess the value of serum glial fibrillary acidic protein (sGFAP) as a biomarker for clinical disease progression and brain volume measurements in natalizumab-treated RRMS patients.

METHODS

sGFAP and neurofilament light (sNfL) were measured in an observational cohort of natalizumab-treated RRMS patients at baseline, +3, +12, and +24 months and at the last sample follow-up (median 5.17 years). sGFAP was compared between significant clinical progressors and non-progressors and related to magnetic resonance imaging (MRI)-derived volumes of the whole brain, ventricle, thalamus, and lesion. The relationship between sGFAP and sNfL was assessed.

RESULTS

A total of 88 patients were included, and 47.7% progressed. sGFAP levels at baseline were higher in patients with gadolinium enhancement (1.3-fold difference, p = 0.04) and decreased in 3 months of treatment (adj. p < 0.001). No association was found between longitudinal sGFAP levels and progressor status. sGFAP at baseline and 12 months was significantly associated with normalized ventricular (positively), thalamic (negatively), and lesion volumes (positively). Baseline and 12-month sGFAP predicted annualized ventricle volume change rate after 1 year of treatment. sGFAP correlated with sNfL at baseline (p < 0.001) and last sample follow-up (p < 0.001) but stabilized earlier.

DISCUSSION

sGFAP levels related to MRI markers of neuroinflammation and neurodegeneration.

Natalizumab Promotes Activation of Peripheral Monocytes in Patients With Multiple Sclerosis

OBJECTIVES

Natalizumab (NTZ), a monoclonal antibody against very late antigen-4 (VLA-4), is one of the most efficient therapies to prevent acute relapses in multiple sclerosis (MS). VLA-4 is the key adhesion molecule for peripheral immune cells, especially lymphocytes to enter the CNS. While its blockade thus virtually abrogates CNS infiltration of these cells, long-term exposure to natalizumab may also affect immune cell function.

METHODS

In this study, we report that in patients with MS, NTZ treatment is associated with an enhanced activation status of peripheral monocytes.

RESULTS

Expression of 2 independent activation markers, CD69 and CD150, was significantly higher on blood monocytes from NTZ-treated patients when compared with those from matched untreated patients with MS, while other properties such as cytokine production remained unchanged.

DISCUSSION

These findings consolidate the concept that peripheral immune cells remain fully competent on NTZ treatment, an excellent asset rare among MS treatments. However, they also suggest that NTZ may exert nondesirable effects on the progressive aspect of MS, where myeloid cells and their chronic activation are attributed a prominent pathophysiologic role.

Secondary Progressive Multiple Sclerosis

Many challenges exist in the precise diagnosis and clinical management of secondary progressive multiple sclerosis (SPMS) because of the lack of definitive clinical, imaging, immunologic, or pathologic criteria that demarcate the transition from relapsing-remitting MS to SPMS. This review provides an overview of the diagnostic criteria/definition and the heterogeneity associated with different SPMS patient populations; it also emphasizes the importance of available prospective/retrospective tools to identify patients with SPMS earlier in the disease course so that approved disease-modifying therapies and nonpharmacological strategies will translate into better outcomes. Delivery of such interventions necessitates an evolving patient-clinician dialog within the context of a multidisciplinary team.

Treatment of Patients with Multiple Sclerosis Transitioning Between Relapsing and Progressive Disease

Multiple sclerosis (MS) is a chronic autoimmune demyelinating and neurodegenerative disease of the central nervous system with a wide variety of clinical phenotypes. In spite of the phenotypic classification of MS patients, current data provide evidence that diffuse neuroinflammation and neurodegeneration coexist in all MS forms, the latter gaining increasing clinical relevance in progressive phases. Given that the transition phase of relapsing-remitting MS (RRMS) to secondary progressive MS (SPMS) is not well defined, and widely accepted criteria for SPMS are lacking, randomised controlled trials (RCTs) specifically designed for the transition phase have not been conducted. This review summarizes primary and secondary analyses and reports derived from phase III prospective clinical RCTs listed in PubMed of compounds authorised through the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) for the treatment of MS. The best data are available for interferon beta-1a (IFNb-1a) subcutaneous (s.c.), IFNb-1b s.c., mitoxantrone and siponimod, the latter being the most modern compound with likely the best risk-to-effect ratio. Moreover, there is a labels discrepancy for many disease-modifying treatments (DMTs) between the FDA and EMA, which have to be taken into consideration when opting for a specific DMT.

MSProDiscuss™ Clinical Decision Support Tool for Identifying Multiple Sclerosis Progression

This article describes the rationale for the development of the MSProDiscuss™ clinical decision support (CDS) tool, its development, and insights into how it can help neurologists improve care for patients with multiple sclerosis (MS). MS is a progressive disease characterized by heterogeneous symptoms and variable disease course. There is growing consensus that MS exists on a continuum, with overlap between relapsing–remitting and secondary progressive phenotypes. Evidence demonstrates that neuroaxonal loss occurs from the outset, that progression can occur independent of relapse activity, and that continuous underlying pathological processes may not be reflected by inflammatory activity indicative of the patient’s immune response. Early intervention can benefit patients, and there is a need for a tool that assists physicians in rapidly identifying subtle signs of MS progression. MSProDiscuss, developed with physicians and patients, facilitates a structured approach to patient consultations. It analyzes multidimensional data via an algorithm to estimate the likelihood of progression (the MSProDiscuss score), the contribution of various symptoms, and the impact of symptoms on daily living, enabling a more personalized approach to treatment and disease management. Data from CDS tools such as MSProDiscuss offer new insights into disease course and facilitate informed decision-making and a holistic approach to MS patient care.

Bruton's Tyrosine Kinase Inhibition in Multiple Sclerosis

PURPOSE OF REVIEW

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) with a chronic and often progressive disease course. The current disease-modifying treatments (DMTs) limit disease progression primarily by dampening immune cell activity in the peripheral blood or hindering their migration from the periphery into the CNS. New therapies are needed to target CNS immunopathology, which is a key driver of disability progression in MS. This article reviews Bruton's Tyrosine Kinase Inhibitors (BTKIs), a new class of experimental therapy that is being intensely evaluated in MS. We focus on the potential peripheral and central mechanisms of action of BTKIs and their use in recent clinical trials in MS.

RECENT FINDINGS

There is evidence that some BTKIs cross the blood-brain barrier and may be superior to currently available DMTs at dampening the chronic neuroinflammatory processes compartmentalized within the CNS that contribute to progressive worsening in people withMS (pwMS). Recently, evobrutinib and tolebrutinib have shown efficacy in phase II clinical trials, and there are numerous ongoing phase III clinical trials of various BTKIs in relapsing and progressive forms of MS. Results from these clinical trials will be essential to understand the efficacy and safety of BTKIs across the spectrum of MS and keydifferences between specific BTKIs when treating pwMS. Inhibition of BTK has emerged as an attractive strategy to target cells of the adaptive and innate immune system outside and within the CNS. BTKIs carry great therapeutic potential across the MS spectrum, where key pathobiology aspects seem confined to the CNS compartment.