Time to steroids impacts visual outcome of optic neuritis in MOGAD.

BACKGROUND: To characterise the response to treatment of inaugural optic neuritis (ON) in patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). METHODS: We searched the French MOGAD database for adults with inaugural ON with a detailed report of acute treatment modalities and measures of high-contrast best-corrected visual acuity (BCVA) at nadir and after 3 months. Predictors of visual outcomes were assessed by multivariable analysis. RESULTS: Among 245 patients with at least one episode of ON, 82 fulfilled all criteria, and data on the peripapillary retinal nerve fibre layer (pRNFL) were available for 44. All patients received methylprednisolone (MP), combined with plasma exchange in 18. After 3 months, 75 of 82 (91%) patients retained full BCVA recovery, and median (range) pRNFL of the affected eye was 72 µm (40-102). Failure to regain 0.0 logarithmic minimum angle of resolution vision (Snellen 20/20) at 3 months was associated with time to first MP treatment ≥10 days (OR 16, 95% CI 1.14 to 213, p=0.01). pRNFL thickness after 3 months was related to better BCVA at nadir and time to first MP treatment <10 days (r2=19%, p=0.004 and r2=11%, p=0.03, respectively). CONCLUSIONS: Time to MP affects functional but also structural visual outcomes of ON in MOGAD.

Improving the decision to switch from first- to second-line therapy in multiple sclerosis: A dynamic scoring system.

BACKGROUND: In relapsing-remitting multiple sclerosis (RRMS), early identification of suboptimal responders can prevent disability progression. OBJECTIVE: We aimed to develop and validate a dynamic score to guide the early decision to switch from first- to second-line therapy. METHODS: Using time-dependent propensity scores (PS) from a French cohort of 12,823 patients with RRMS, we constructed one training and two validation PS-matched cohorts to compare the switched patients to second-line treatment and the maintained patients. We used a frailty Cox model for predicting individual hazard ratios (iHRs). RESULTS: From the validation PS-matched cohort of 348 independent patients with iHR ⩽ 0.69, we reported the 5-year relapse-free survival at 0.14 (95% confidence interval (CI) 0.09-0.22) for the waiting group and 0.40 (95% CI 0.32-0.51) for the switched group. From the validation PS-matched cohort of 518 independent patients with iHR > 0.69, these values were 0.37 (95% CI 0.30-0.46) and 0.44 (95% CI 0.37-0.52), respectively. CONCLUSIONS: By using the proposed dynamic score, we estimated that at least one-third of patients could benefit from an earlier switch to prevent relapse.

Cumulative effects of therapies on disability in relapsing multiple sclerosis.

BACKGROUND: Long-term effectiveness of treatment remains a key question in multiple sclerosis (MS) and the cumulative effects of past treatment have not been investigated so far. OBJECTIVE: Explore the relationship between treatment exposure and disability risk in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: A total of 2285 adult patients from the French nationwide cohort were included. Outcomes were irreversible EDSS4, and conversion to secondary progression of multiple sclerosis (SPMS). Associations between treatments and risk of disability were assessed using a novel weighted cumulative exposure model, assuming a 3-year lag to account for reverse causality. This flexible approach accounts for past exposure in a multivariate Cox proportional hazards model by computing a weight function. RESULTS: At baseline, mean ± standard deviation age of patients was 33.4 ± 8.9 years and 75.0% were women. A 15-year continuous treatment starting 20 years ago was associated with a decrease in risk of 26% for irreversible EDSS4, and 34% for SPMS compared to a 5-year treatment starting 10 years ago. The risk of disability decreased with increasing duration of exposure to disease-modifying treatment (DMT). CONCLUSION: Long-term use of treatments in RRMS has a stronger beneficial cumulative impact than only early uses and delays the occurrence of moderate disability and conversion to SPMS.

BEST-MS: A prospective head-to-head comparative study of natalizumab and fingolimod in active relapsing MS.

BACKGROUND: There are few head-to-head studies to compare highly active treatments in multiple sclerosis (MS). OBJECTIVE: The aim of this study was to compare the effectiveness between natalizumab (NTZ) and fingolimod (FTY) in active relapsing-remitting MS. METHOD: Best Escalation STrategy in Multiple Sclerosis (BEST-MS) is a multicentric, prospective study with a 12-month follow-up including patients with active MS. Treatment choice was at the discretion of physician. Clinical and magnetic resonance imaging (MRI) data were collected at baseline and at 12 months. The primary outcome was the proportion of patients reaching no evidence of disease activity (NEDA) at 12 months. Secondary outcomes included annualized relapse rate and MRI activity. RESULTS: A total of 223 patients were included (NTZ: 109 and FTY: 114). Treatment groups were well balanced at baseline. Proportion of NEDA patients was 47.8% in NTZ group versus 30.4% in FTY group (p = 0.015). This superiority was driven by annualized relapse rate and MRI activity. In the multivariate analysis, treatment group was the only factor associated with NEDA at 12 months with a lower probability in FTY group (odds ratio (OR) = 0.49, p = 0.029). CONCLUSION: BEST-MS is a prospective study that compared head-to-head the effectiveness of NTZ and FTY in active relapsing-remitting MS. Our results suggest a superiority of NTZ over FTY.

Assessing the experience of the quality of care of patients living with multiple sclerosis and their caregivers: The MusiCare questionnaire.

BACKGROUND AND PURPOSE: Patients with a chronic illness, such as multiple sclerosis (MS), and their natural caregivers have a specific experience of healthcare and health services. These experiences need to be assessed to evaluate the quality of care. Our objective was to develop a French-language questionnaire to evaluate the quality of care as experienced by MS patients and their natural caregivers. METHODS: Eligible patients had been diagnosed with MS according to the McDonald criteria. Eligible caregivers were individuals designated by the patients. The MusiCare questionnaire was developed in two standard phases: (i) item generation, based on interviews with patients and caregivers; and (ii) validation, consisting of validity, reliability, external validity, reproducibility, and responsiveness measures. RESULTS: In total, 1088 patients (n = 660) and caregivers (n = 488) were recruited. The initial 64-item version of MusiCare was administered to a random subsample (n = 748). The validation process generated a 35-item questionnaire. Internal consistency and scalability were satisfactory. Testing of the external validity revealed expected associations between MusiCare scores and sociodemographic and clinical data. The questionnaire showed good reproducibility and responsiveness. CONCLUSIONS: The availability of a reliable and validated French-language self-report questionnaire probing the experience of the quality of care for MS will allow the feedback of patients and caregivers to be incorporated into a continuous healthcare quality-improvement strategy.

Outcome and risk of recurrence in a large cohort of idiopathic longitudinally extensive transverse myelitis without AQP4/MOG antibodies.

BACKGROUND: Longitudinally extensive transverse myelitis (LETM) is classically related to aquaporin (AQP4)-antibodies (Ab) neuromyelitis optica spectrum disorders (NMOSD) or more recently to myelin oligodendrocyte glycoprotein (MOG)-Ab associated disease. However, some patients remain negative for any diagnosis, despite a large work-up including AQP4-Ab and MOG-Ab. Data about natural history, disability outcome, and treatment are limited in this group of patients. We aimed to (1) describe clinical, biological, and radiological features of double seronegative LETM patients; (2) assess the clinical course and identify prognostic factors; and (3) assess the risk of recurrence, according to maintenance immunosuppressive therapy. METHODS: Retrospective evaluation of patients with a first episode of LETM, tested negative for AQP-Ab and MOG-Ab, from the French nationwide observatory study NOMADMUS. RESULTS: Fifty-three patients (median age 38 years (range 16-80)) with double seronegative LETM were included. Median nadir EDSS at onset was 6.0 (1-8.5), associated to a median EDSS at last follow-up of 4.0 (0-8). Recurrence was observed in 24.5% of patients in the 18 following months, with a median time to first relapse of 5.7 months. The risk of recurrence was lower in the group of patients treated early with an immunosuppressive drug (2/22, 9%), in comparison with untreated patients (10/31, 32%). CONCLUSIONS: A first episode of a double seronegative LETM is associated to a severe outcome and a high rate of relapse in the following 18 months, suggesting that an early immunosuppressive treatment may be beneficial in that condition.

High-dose biotin in progressive multiple sclerosis: A prospective study of 178 patients in routine clinical practice.

BACKGROUND: A recent controlled trial suggested that high-dose biotin supplementation reverses disability progression in patients with progressive multiple sclerosis. OBJECTIVE: To analyze the impact of high-dose biotin in routine clinical practice on disability progression at 12 months. METHODS: Progressive multiple sclerosis patients who started high-dose biotin at Nantes or Rennes Hospital between 3 June 2015 and 15 September 2017 were included in this prospective study. Disability outcome measures, patient-reported outcome measures, relapses, magnetic resonance imaging (MRI) data, and adverse events were collected at baseline, 6, and 12 months. RESULTS: A total of 178 patients were included. At baseline, patients were 52.0 ± 9.4 years old, mean Expanded Disability Status Scale (EDSS) score was 6.1 ± 1.3, mean disease duration was 16.9 ± 9.5 years. At 12 months, 3.8% of the patients had an improved EDSS score. Regarding the other disability scales, scores either remained stable or increased significantly. In total, 47.4% of the patients described stability, 27.6% felt an improvement, and 25% described a worsening. Four patients (2.2%) had a relapse. Of the 74 patients (41.6%) who underwent an MRI, 20 (27.0%) had new T2 lesions, 8 (10.8%) had gadolinium-enhancing lesions. Twenty-five (14%) reported adverse event. CONCLUSION: In this study, high-dose biotin did not seem to be associated with a clear improvement in disability.

An intermediate level of CD161 expression defines a novel activated, inflammatory, and pathogenic subset of CD8+ T cells involved in multiple sclerosis.

Several lines of evidence support a key role for CD8+ T cells in central nervous system tissue damage of patients with multiple sclerosis. However, the precise phenotype of the circulating CD8+ T cells that may be recruited from the peripheral blood to invade the CNS remains largely undefined to date. It has been suggested that IL-17 secreting CD8 (Tc17) T cells may be involved, and in humans these cells are characterized by the expression of CD161. We focused our study on a unique and recently described subset of CD8 T cells characterized by an intermediate expression of CD161 as its role in neuroinflammation has not been investigated to date. The frequency, phenotype, and function of CD8+ T cells with an intermediate CD161 expression level were characterized ex-vivo, in vitro, and in situ using RNAseq, RT-PCR, flow cytometry, TCR sequencing, and immunohistofluorescence of cells derived from healthy volunteers (n = 61), MS subjects (n = 90), as well as inflammatory (n = 15) and non-inflammatory controls (n = 6). We report here that CD8+CD161int T cells present characteristics of effector cells, up-regulate cell-adhesion molecules and have an increased ability to cross the blood-brain barrier and to secrete IL-17, IFNγ, GM-CSF, and IL-22. We further demonstrate that these cells are recruited and enriched in the CNS of MS subjects where they produce IL-17. In the peripheral blood, RNAseq, RT-PCR, high-throughput TCR repertoire analyses, and flow cytometry confirmed an increased effector and transmigration pattern of these cells in MS patients, with the presence of supernumerary clones compared to healthy controls. Our data demonstrate that intermediate levels of CD161 expression identifies activated and effector CD8+ T cells with pathogenic properties that are recruited to MS lesions. This suggests that CD161 may represent a biomarker and a valid target for the treatment of neuroinflammation.

Neuropathologic, phenotypic and functional analyses of Mucosal Associated Invariant T cells in Multiple Sclerosis.

BACKGROUND: The involvement of Mucosal Associated Invariant T (MAIT) cells, which are anti-microbial semi-invariant T cells, remains elusive in Multiple Sclerosis (MS). OBJECTIVE: Deciphering the potential involvement of MAIT cells in the MS inflammatory process. METHODS: By flow cytometry, blood MAIT cells from similar cohorts of MS patients and healthy volunteers (HV) were compared for frequency, phenotype, activation potential after in vitro TCR engagement by bacterial ligands and transmigration abilities through an in vitro model of blood-brain barrier. MS CNS samples were also studied by immunofluorescent staining and quantitative PCR. RESULTS AND CONCLUSION: Blood MAIT cells from relapsing-remitting MS patients and HV presented similar frequency, ex vivo effector phenotype and activation abilities. MAIT cells represented 0.5% of the total infiltrating T cells on 39 MS CNS lesions. This is low as compared to blood frequency (p<0.001), but consistent with their low transmigration rate. Finally, transcriptional over-expression of MR1 - which presents cognate antigens to MAIT cells - and of the activating cytokines IL-18 and IL-23 was evidenced in MS lesions, suggesting that the CNS microenvironment is suited to activate the few infiltrating MAIT cells. Taken together, these data place MAIT cells from MS patients as minor components of the inflammatory pathological process.

Oral versus intravenous high-dose methylprednisolone for treatment of relapses in patients with multiple sclerosis (COPOUSEP): a randomised, controlled, double-blind, non-inferiority trial.

BACKGROUND: High doses of intravenous methylprednisolone are recommended to treat relapses in patients with multiple sclerosis, but can be inconvenient and expensive. We aimed to assess whether oral administration of high-dose methylprednisolone was non-inferior to intravenous administration. METHODS: We did this multicentre, double-blind, randomised, controlled, non-inferiority trial at 13 centres for multiple sclerosis in France. We enrolled patients aged 18-55 years with relapsing-remitting multiple sclerosis who reported a relapse within the previous 15 days that caused an increase of at least one point in one or more scores on the Kurtzke Functional System Scale. With use of a computer-generated randomisation list and in blocks of four, we randomly assigned (1:1) patients to either oral or intravenous methylprednisolone, 1000 mg, once a day for 3 days. Patients, treating physicians and nurses, and data and outcome assessors were all masked to treatment allocation, which was achieved with the use of saline solution and placebo capsules. The primary endpoint was the proportion of patients who had improved by day 28 (decrease of at least one point in most affected score on Kurtzke Functional System Scale), without need for retreatment with corticosteroids, in the per-protocol population. The trial was powered to assess non-inferiority of oral compared with intravenous methylprednisolone with a predetermined non-inferiority margin of 15%. This trial is registered with ClinicalTrials.gov, number NCT00984984. FINDINGS: Between Jan 29, 2008, and June 14, 2013, we screened 200 patients and enrolled 199. We randomly assigned 100 patients to oral methylprednisolone and 99 patients to intravenous methylprednisolone with a mean time from relapse onset to treatment of 7·0 days (SD 3·6) and 7·4 days (3·9), respectively. In the per-protocol population, 66 (81%) of 82 patients in the oral group and 72 (80%) of 90 patients in the intravenous group achieved the primary endpoint (absolute treatment difference 0·5%, 90% CI -9·5 to 10·4). Rates of adverse events were similar, but insomnia was more frequently reported in the oral group (77 [77%]) than in the intravenous group (63 [64%]). INTERPRETATION: Oral administration of high-dose methylprednisolone for 3 days was not inferior to intravenous administration for improvement of disability scores 1 month after treatment and had a similar safety profile. This finding could have implications for access to treatment, patient comfort, and cost, but indication should always be properly considered by clinicians. FUNDING: French Health Ministry, Ligue Française contre la SEP, Teva.

Adult-onset genetic leukoencephalopathies: a MRI pattern-based approach in a comprehensive study of 154 patients.

Inherited white matter diseases are rare and heterogeneous disorders usually encountered in infancy. Adult-onset forms are increasingly recognized. Our objectives were to determine relative frequencies of genetic leukoencephalopathies in a cohort of adult-onset patients and to evaluate the effectiveness of a systematic diagnostic approach. Inclusion criteria of this retrospective study were: (i) symmetrical involvement of white matter on the first available brain MRI; (ii) age of onset above 16 years. Patients with acquired diseases were excluded. Magnetic resonance imaging analysis identified three groups (vascular, cavitary and non-vascular/non-cavitary) in which distinct genetic and/or biochemical testing were realized. One hundred and fifty-four patients (male/female = 60/94) with adult-onset leukoencephalopathies were identified. Mean age of onset was 38.6 years. In the vascular group, 41/55 patients (75%) finally had a diagnosis [including CADASIL (cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy, n = 32) and COL4A1 mutation, n = 7]. In the cavitary group, 13/17 (76%) patients had a diagnosis of EIF2B-related disorder. In the third group (n = 82), a systematic biological screening allowed a diagnosis in 23 patients (28%) and oriented direct genetic screening identified 21 additional diseases (25.6%). Adult-onset genetic leukoencephalopathies are a rare but probably underestimated entity. Our study confirms the use of a magnetic resonance imaging-based classification with a final diagnosis rate of 64% (98/154) cases.

Unaltered regulatory B-cell frequency and function in patients with multiple sclerosis.

Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS) typically characterized by the recruitment of T cells into the CNS. However, certain subsets of B cells have been shown to negatively regulate autoimmune diseases and some data support a prominent role for B cells in MS physiopathology. For B cells in MS patients we analyzed subset frequency, cytokine secretion ability and suppressive properties. No differences in the frequencies of the B-cell subsets or in their ability to secrete cytokines were observed between MS and healthy volunteers (HV). Prestimulated B cells from MS patients also inhibited CD4(+)CD25(-) T cell proliferation with a similar efficiency as B cells from HV. Altogether, our data show that, in our MS patient cohort, regulatory B cells have conserved frequency and function.

Efficacy and comparison of corticosteroids only and corticosteroids with plasmapheresis or intravenous immunoglobulin for the treatment of optic neuritis in demyelinating disease: A systematic review and network meta-analysis.

PURPOSE: To compare the efficacy of treatment of optic neuritis (ON) with corticosteroids (CTC) alone, CTC+plasmapheresis (PLP), and CTC+intravenous immunoglobulin (IVIG). DESIGN: After an episode of ON, although visual recovery is usually good, some patients may have significant visual sequelae. While the efficacy of first-line CTC is now indisputable, there is no consensus on the nature of second-line treatment. To date, no systematic review has compared the efficacy of treatment of ON with CTC alone, CTC+plasmapheresis (PLP), and CTC+intravenous immunoglobulin (IVIG). A meta-analysis is needed to compare the efficacy of PLP and IVIG in steroid-resistant ON. METHODS: This systematic review included all studies comparing at least two of the three treatments for steroid-resistant ON (CTC alone, CTC+PLP, and CTC+IVIG). From all articles published on PubMed between January 2000 and June 2022, two independent ophthalmologists selected studies of interest using the PRISMA method. Methodology, patient characteristics, and outcomes were identified. A network metaanalysis was then performed to compare the efficacy of the three treatments. RESULTS: Six comparative studies were included, representing 209 patients. The percentage of significant visual recovery after CTC alone, CTC+PLP, and CTC+IVIG in the acute treatment of steroid-resistant ON was 30 %, 45 %, and 77 %, respectively. Comparison of CTC+IVIG vs CTC alone, CTC+PLP vs CTC only, and CTC+PLP vs CTC+IVIG yielded odds ratios of 12.81, 2.47, and 0.19 respectively. CONCLUSION: Treatment of steroid-resistant ON with CTC+PLP or CTC+IVIG is more effective than treatment with CTC alone. Although no study has directly compared the two treatments, IVIG may be more effective than PLP.

Investigating the metabolite signature of an altered oral microbiota as a discriminant factor for multiple sclerosis: a pilot study.

In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully elucidated. In a pilot case-controlled study, we carried out simultaneous characterization of faecal and oral microbiota and conducted an in-depth analysis of bacterial alterations associated with MS. Using 16S rRNA sequencing and metabolic inference tools, we compared the oral/faecal microbiota and bacterial metabolism pathways in French MS patients (n = 14) and healthy volunteers (HV, n = 21). A classification model based on metabolite flux balance was established and validated in an independent German cohort (MS n = 12, HV n = 38). Our analysis revealed decreases in diversity indices and oral/faecal compartmentalization, the depletion of commensal bacteria (Aggregatibacter and Streptococcus in saliva and Coprobacter and Roseburia in faeces) and enrichment of inflammation-associated bacteria in MS patients (Leptotrichia and Fusobacterium in saliva and Enterobacteriaceae and Actinomyces in faeces). Several microbial pathways were also altered (the polyamine pathway and remodelling of bacterial surface antigens and energetic metabolism) while flux balance analysis revealed associated alterations in metabolite production in MS (nitrogen and nucleoside). Based on this analysis, we identified a specific oral metabolite signature in MS patients, that could discriminate MS patients from HV and rheumatoid arthritis patients. This signature allowed us to create and validate a discrimination model on an independent cohort, which reached a specificity of 92%. Overall, the oral and faecal microbiomes were altered in MS patients. This pilot study highlights the need to study the oral microbiota and oral health implications in patients with autoimmune diseases on a larger scale and suggests that knowledge of the salivary microbiome could help guide the identification of new pathogenic mechanisms associated with the microbiota in MS patients.

Highly Effective Therapies as First-Line Treatment for Pediatric-Onset Multiple Sclerosis.

Importance: Moderately effective therapies (METs) have been the main treatment in pediatric-onset multiple sclerosis (POMS) for years. Despite the expanding use of highly effective therapies (HETs), treatment strategies for POMS still lack consensus. Objective: To assess the real-world association of HET as an index treatment compared with MET with disease activity. Design, Setting, and Participants: This was a retrospective cohort study conducted from January 1, 2010, to December 8, 2022, until the last recorded visit. The median follow-up was 5.8 years. A total of 36 French MS centers participated in the Observatoire Français de la Sclérose en Plaques (OFSEP) cohort. Of the total participants in OFSEP, only treatment-naive children with relapsing-remitting POMS who received a first HET or MET before adulthood and at least 1 follow-up clinical visit were included in the study. All eligible participants were included in the study, and none declined to participate. Exposure: HET or MET at treatment initiation. Main Outcomes and Measures: The primary outcome was the time to first relapse after treatment. Secondary outcomes were annualized relapse rate (ARR), magnetic resonance imaging (MRI) activity, time to Expanded Disability Status Scale (EDSS) progression, tertiary education attainment, and treatment safety/tolerability. An adapted statistical method was used to model the logarithm of event rate by penalized splines of time, allowing adjustment for effects of covariates that is sensitive to nonlinearity and interactions. Results: Of the 3841 children (5.2% of 74 367 total participants in OFSEP), 530 patients (mean [SD] age, 16.0 [1.8] years; 364 female [68.7%]) were included in the study. In study patients, both treatment strategies were associated with a reduced risk of first relapse within the first 2 years. HET dampened disease activity with a 54% reduction in first relapse risk (adjusted hazard ratio [HR], 0.46; 95% CI, 0.31-0.67; P < .001) sustained over 5 years, confirmed on MRI activity (adjusted odds ratio [OR], 0.34; 95% CI, 0.18-0.66; P = .001), and with a better tolerability pattern than MET. The risk of discontinuation at 2 years was 6 times higher with MET (HR, 5.97; 95% CI, 2.92-12.20). The primary reasons for treatment discontinuation were lack of efficacy and intolerance. Index treatment was not associated with EDSS progression or tertiary education attainment (adjusted OR, 0.51; 95% CI, 0.24-1.10; P = .09). Conclusions and Relevance: Results of this cohort study suggest that compared with MET, initial HET in POMS was associated with a reduction in the risk of first relapse with an optimal outcome within the first 2 years and was associated with a lower rate of treatment switching and a better midterm tolerance in children. These findings suggest prioritizing initial HET in POMS, although long-term safety studies are needed.

Acute Clinical Events Identified as Relapses With Stable Magnetic Resonance Imaging in Multiple Sclerosis.

Importance: Understanding the association between clinically defined relapses and radiological activity in multiple sclerosis (MS) is essential for patient treatment and therapeutic development. Objective: To investigate clinical events identified as relapses but not associated with new T2 lesions or gadolinium-enhanced T1 lesions on brain and spinal cord magnetic resonance imaging (MRI). Design, Setting, and Participants: This multicenter observational cohort study was conducted between January 2015 and June 2023. Data were extracted on June 8, 2023, from the French MS registry. All clinical events reported as relapses in patients with relapsing-remitting MS were included if brain and spinal cord MRI was performed within 12 and 24 months before the event, respectively, and 50 days thereafter with gadolinium injection. Exposures: Events were classified as relapses with active MRI (RAM) if a new T2 lesion or gadolinium-enhanced T1 lesion appeared on brain or spinal cord MRI or as acute clinical events with stable MRI (ACES) otherwise. Main Outcomes and Measures: Factors associated with ACES were investigated; patients with ACES and RAM were compared regarding Expanded Disability Status Scale (EDSS) course, relapse rate, confirmed disability accrual (CDA), relapse-associated worsening (RAW), progression independent of relapse activity (PIRA), and transition to secondary progressive (SP) MS, and ACES and RAM rates under each disease-modifying therapy (DMT) were estimated. Results: Among 31 885 clinical events, 637 in 608 patients (493 [77.4%] female; mean [SD] age, 35.8 [10.7] years) were included. ACES accounted for 166 (26.1%) events and were more likely in patients receiving highly effective DMTs, those with longer disease duration (odds ratio [OR], 1.04; 95% CI, 1.01-1.07), or those presenting with fatigue (OR, 2.14; 95% CI, 1.15-3.96). ACES were associated with significant EDSS score increases, lower than those found for RAM. Before the index event, patients with ACES experienced significantly higher rates of relapse (relative rate [RR], 1.21; 95% CI, 1.01-1.46), CDA (hazard ratio [HR], 1.54; 95% CI, 1.13-2.11), and RAW (HR, 1.72; 95% CI, 1.20-2.45). Patients with ACES were at significantly greater risk of SP transition (HR, 2.58; 95% CI, 1.02-6.51). Although RAM rate decreased with DMTs according to their expected efficacy, ACES rate was stable across DMTs. Conclusions and Relevance: The findings in this study introduce the concept of ACES in MS, which accounted for one-fourth of clinical events identified as relapses.

Peer support impact on therapeutic adherence in patients with multiple sclerosis: a mixed-methods pilot trial protocol.

INTRODUCTION: Patient partnership is a key component of patient-centred care. One form of partnership is individual peer support, which can improve patients' quality of life and adherence to treatment. Patient with multiple sclerosis could benefit from this type of support, but such an intervention has not been explored in the literature.We propose in this article a pilot study protocol to assess the feasibility and acceptability of healthcare-integrated individual peer support, and the feasibility of a large-scale efficacy trial. METHODS AND ANALYSIS: The PAIR-SEP study is a mixed-methods pilot clinical trial combining quantitative and qualitative approaches. Sixty patients with relapsing-remitting multiple sclerosis undergoing drug therapy from the Neurology centre of Nantes University Hospital (France) will be randomised on a 1:1 ratio to receive either usual care only or usual care combined with peer support (three individual sessions at 1, 3 and 5 months with a peer helper).We will evaluate clinical outcomes in preparation of the large-scale trial: therapeutic adherence 6 months after baseline, therapeutic compliance, quality of life, anxiety and depression, social support. All dimensions will be assessed using validated health questionnaires at baseline and at 6 months.Intervention's acceptability and feasibility will be evaluated using qualitative methods: undirected interviews with patients from the intervention group and separate focus-groups with the peer helpers the healthcare team. ETHICS AND DISSEMINATION: Ethical approval was obtained from the local ethics committee on 1 October 2022. This study was designed in collaboration with multiple sclerosis peer helpers.The trial findings will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05519553.

Discontinuation of second- versus first-line disease-modifying treatment in middle-aged patients with multiple sclerosis.

BACKGROUND AND PURPOSE: There has been scant research on the consequences of discontinuing second-line disease-modifying treatment (DMT) in middle-aged patients with multiple sclerosis (MS). The objective was therefore to examine the occurrence of focal inflammatory activity after the discontinuation of second versus first-line DMT in patients over 45 years. METHODS: Patients who had been treated for at least 6 months with second (natalizumab, fingolimod, anti CD20) or first-line DMT and who stopped their DMT were retrospectively included. Kaplan-Meier survival curves were used to study the occurrence of relapse and MRI activity according to the type of DMT stopped. Proportional hazard Cox models were calculated to identify factors associated with focal inflammatory activity. The annualized relapse rate was calculated under treatment and for every 3 months after DMT discontinuation. RESULTS: We included 232 patients (median age: 52.8 years), 49 of whom stopped second-line DMT. The probability of having a relapse within the year following discontinuation was 6% for first-line DMT, 9% for fingolimod and 43% for natalizumab. In multivariate analysis, the probability of relapse after DMT discontinuation was significantly increased with natalizumab compared to first-line DMT (HR = 3.24; 95% CI [1.52; 6.90]). A peak of relapse was observed at 0-3 months after stopping natalizumab or fingolimod. CONCLUSION: Our study suggests that the risk of inflammatory activity is greater after discontinuation of natalizumab compared to other DMT even in middle-aged patients. As for younger patients, natalizumab discontinuation should only be considered if there is an adequate substitution of a different therapy. .

Aglycosylated extracellular loop of inwardly rectifying potassium channel 4.1 (KCNJ10) provides a target for autoimmune neuroinflammation.

Multiple sclerosis is an autoimmune disease of the central nervous system. Yet, the autoimmune targets are still undefined. The extracellular e1 sequence of KCNJ10, the inwardly rectifying potassium channel 4.1, has been subject to fierce debate for its role as a candidate autoantigen in multiple sclerosis. Inwardly rectifying potassium channel 4.1 is expressed in the central nervous system but also in peripheral tissues, raising concerns about the central nervous system-specificity of such autoreactivity. Immunization of C57Bl6/J female mice with the e1 peptide (amino acids 83-120 of Kir4.1) induced anti-e1 immunoglobulin G- and T-cell responses and promoted demyelinating encephalomyelitis with B cell central nervous system enrichment in leptomeninges and T cells/macrophages in central nervous system parenchyma from forebrain to spinal cord, mostly in the white matter. Within our cohort of multiple sclerosis patients (n = 252), 6% exhibited high anti-e1 immunoglobulin G levels in serum as compared to 0.7% in the control cohort (n = 127; P = 0.015). Immunolabelling of inwardly rectifying potassium channel 4.1-expressing white matter glia with the anti-e1 serum from immunized mice increased during murine autoimmune neuroinflammation and in multiple sclerosis white matter as compared with controls. Strikingly, the mouse and human anti-e1 sera labelled astrocytoma cells when N-glycosylation was blocked with tunicamycin. Western blot confirmed that neuroinflammation induces Kir4.1 expression, including its shorter aglycosylated form in murine experimental autoencephalomyelitis and multiple sclerosis. In addition, recognition of inwardly rectifying potassium channel 4.1 using mouse anti-e1 serum in Western blot experiments under unreduced conditions or in cells transfected with the N-glycosylation defective N104Q mutant as compared to the wild type further suggests that autoantibodies target an e1 conformational epitope in its aglycosylated form. These data highlight the e1 sequence of inwardly rectifying potassium channel 4.1 as a valid central nervous system autoantigen with a disease/tissue-specific post-translational antigen modification as potential contributor to autoimmunity in some multiple sclerosis patients.

Immune Profiling Reveals the T-Cell Effect of Ocrelizumab in Early Relapsing-Remitting Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Ocrelizumab (OCR), a humanized anti-CD20 monoclonal antibody, is highly efficient in patients with relapsing-remitting multiple sclerosis (RR-MS). We assessed early cellular immune profiles and their association with disease activity at treatment start and under therapy, which may provide new clues on the mechanisms of action of OCR and on the disease pathophysiology. METHODS: A first group of 42 patients with an early RR-MS, never exposed to disease-modifying therapy, was included in 11 centers participating to an ancillary study of the ENSEMBLE trial (NCT03085810) to evaluate the effectiveness and safety of OCR. The phenotypic immune profile was comprehensively assessed by multiparametric spectral flow cytometry at baseline and after 24 and 48 weeks of OCR treatment on cryopreserved peripheral blood mononuclear cells and analyzed in relation to disease clinical activity. A second group of 13 untreated patients with RR-MS was included for comparative analysis of peripheral blood and CSF. The transcriptomic profile was assessed by single-cell qPCRs of 96 genes of immunologic interest. RESULTS: Using an unbiased analysis, we found that OCR as an effect on 4 clusters of CD4+ T cells: one corresponding to naive CD4+ T cells was increased, the other clusters corresponded to effector memory (EM) CD4+CCR6- T cells expressing homing and migration markers, 2 of them also expressing CCR5 and were decreased by the treatment. Of interest, one CD8+ T-cell cluster was decreased by OCR corresponding to EM CCR5-expressing T cells with high expression of the brain homing markers CD49d and CD11a and correlated with the time elapsed since the last relapse. These EM CD8+CCR5+ T cells were enriched in the CSF of patients with RR-MS and corresponded to activated and cytotoxic cells. DISCUSSION: Our study provides novel insights into the mode of action of anti-CD20, pointing toward the role of EM T cells, particularly a subset of CD8 T cells expressing CCR5.