Treatment Effect on Brain Atrophy Correlates with Treatment Effect on Cognition in Multiple Sclerosis.

OBJECTIVE: The purpose of this study was to evaluate the extent to which treatment effect on magnetic resonance imaging (MRI)-derived measures of brain atrophy and focal lesions can mediate, at the trial level, the treatment effect on cognitive outcomes in multiple sclerosis (MS). METHODS: We collected all published randomized clinical trials in MS lasting at least 2 years and including as end points: active MRI lesions (defined as new/enlarging T2 lesions), brain atrophy (defined as a change in brain volume between month 12 and month 24), and change in cognitive performance (assessed by the Paced Auditory Serial Addition Test [PASAT]). Relative reductions were used to quantify the treatment effect on MRI markers (lesions and atrophy), whereas the standardized mean difference (Hedges g) between baseline and follow-up cognitive assessment was used to quantify the treatment effects on cognition. A linear regression, weighted for trial size, was used to assess the relationship between the treatment effects on MRI markers and cognition. RESULTS: Fourteen trials including more than 8,813 patients with MS were included in the meta-regression. Treatment effect on cognition was strongly associated with the treatment effect on brain atrophy (R2 = 0.79, p < 0.001), but was not correlated with the treatment effect on active MRI lesions (R2 = 0.16, p = 0.14). INTERPRETATION: Results reported here suggest that brain atrophy, a well-established MRI marker in MS clinical trials, can be used as a main outcome for clinical trials with drugs targeting cognitive impairment and neurodegeneration. ANN NEUROL 2023;94:925-932.

Dimethyl Fumarate Delays Multiple Sclerosis in Radiologically Isolated Syndrome.

OBJECTIVE: The radiologically isolated syndrome (RIS) represents the earliest detectable pre-clinical phase of multiple sclerosis (MS). This study evaluated the impact of therapeutic intervention in preventing first symptom manifestation at this stage in the disease spectrum. METHODS: We conducted a multi-center, randomized, double-blinded, placebo-controlled study involving people with RIS. Individuals without clinical symptoms typical of MS but with incidental brain MRI anomalies consistent with central nervous system (CNS) demyelination were included. Within 12 MS centers in the United States, participants were randomly assigned 1:1 to oral dimethyl fumarate (DMF) 240 mg twice daily or placebo. The primary endpoint was the time to onset of clinical symptoms attributable to a CNS demyelinating event within a follow-up period of 96 weeks. An intention-to-treat analysis was applied to all participating individuals in the primary and safety investigations. The study is registered at ClinicalTrials.gov, NCT02739542 (ARISE). RESULTS: Participants from 12 centers were recruited from March 9, 2016, to October 31, 2019, with 44 people randomized to dimethyl fumarate and 43 to placebo. Following DMF treatment, the risk of a first clinical demyelinating event during the 96-week study period was highly reduced in the unadjusted Cox proportional-hazards regression model (hazard ratio [HR] = 0.18, 95% confidence interval [CI] = 0.05-0.63, p = 0.007). More moderate adverse reactions were present in the DMF (34 [32%]) than placebo groups (19 [21%]) but severe events were similar (DMF, 3 [5%]; placebo, 4 [9%]). INTERPRETATION: This is the first randomized clinical trial demonstrating the benefit of a disease-modifying therapy in preventing a first acute clinical event in people with RIS. ANN NEUROL 2023;93:604-614.

Emulating randomised clinical trials in relapsing-remitting multiple sclerosis with non-randomised real-world evidence: an application using data from the MSBase Registry.

BACKGROUND: To mimic as closely as possible a randomised controlled trial (RCT) and calibrate the real-world evidence (RWE) studies against a known treatment effect would be helpful to understand if RWE can support causal conclusions in selected circumstances. The aim was to emulate the TRANSFORMS trial comparing Fingolimod (FTY) versus intramuscular interferon ß-1a (IFN) using observational data. METHODS: We extracted from the MSBase registry all the patients with relapsing-remitting multiple sclerosis (RRMS) collected in the period 2011-2021 who received IFN or FTY (0.5 mg) and with the same inclusion and exclusion criteria of the TRANSFORMS RCT. The primary endpoint was the annualised relapse rate (ARR) over 12 months. Patients were 1:1 propensity-score (PS) matched. Relapse-rate ratio (RR) was calculated by mean of a negative binomial regression. RESULTS: A total of 4376 patients with RRMS (1140 in IFN and 3236 in FTY) were selected. After PS, 856 patients in each group were matched. The ARR was 0.45 in IFN and 0.25 in FTY with a significant difference between the two groups (RR: 0.55, 95% CI: 0.45 to 0.68; p<0.001). The result of the emulation was very similar and fell within the 95% CI of that observed in the RCT (RR: 0.49, 95% CI: 0.37 to 0.64; p<0.001) with a standardised difference of 0.66 (p=0.51). CONCLUSIONS: By applying the same inclusion and exclusion criteria used in the RCT and employing appropriate methodology, we successfully replicated the RCT results with only minor discrepancies. Also, even if the confounding bias cannot be fully eliminated, conducting a rigorous target trial emulation could still yield valuable insights for comparative effectiveness research.

Therapeutic lag: Is treatment effect delayed in progressive MS?

BACKGROUND: Randomized clinical trials (RCTs) in progressive multiple sclerosis (MS) often revealed non-significant treatment effects on disability progression. OBJECTIVES: To investigate whether the failure to detect a significant benefit from treatment may be motivated by a delay in treatment effect, possibly related to baseline characteristics. METHODS: We re-analyzed data from two RCTs testing interferon-beta and glatiramer-acetate versus placebo in progressive MS with no significant effect on EDSS progression. We first designed a time-dependent Cox model with no treatment effect up to time = t0, and constant hazard ratio (HR) after time = t0. We selected the best-fitting t0 from 0 (standard Cox model) to 2.5 years. Furthermore, we modeled the delay as a function of baseline EDSS and fitted the resulting Cox model to the merged dataset. RESULTS: The time-dependent Cox model revealed a significant benefit of treatment delayed by t0 = 2.5 years for the SPECTRIMS study (HR = 0.65 (0.43-0.98), p = 0.041), and delayed by t0 = 2 years for the PROMISE study (HR = 0.65, (0.42-0.99), p = 0.044). In the merged dataset, the HR for the EDSS-dependent delayed effect was 0.68 (0.56, 0.82), p < 0.001. CONCLUSION: The assumption of a delayed treatment effect improved the fit to the data of the two examined RCTs, uncovering a significant, although shifted, benefit of treatment.

Race and ethnicity in multiple sclerosis phase 3 clinical trials: A systematic review.

BACKGROUND: Distinctive differences in multiple sclerosis (MS) have been observed by race and ethnicity. We aim to (1) assess how often race and ethnicity were reported in clinical trials registered on ClinicalTrials.gov, (2) evaluate whether the population was diverse enough, and (3) compare with publications. METHODS: We included phase 3 clinical trials registered with results on ClinicalTrials.gov between 2007 and 2023. When race and/or ethnicity were reported, we searched for the corresponding publications. RESULTS: Out of the 99 included studies, 56% reported race and/or ethnicity, of which only 26% of those primarily completed before 2017. Studies reporting race or ethnicity contributed to a total of 33,891 participants, mainly enrolled in Eastern Europe. Most were White (93%), and the median percentage of White participants was 93% (interquartile range (IQR) = 86%-98%), compared to 3% for Black (IQR = 1%-12%) and 0.2% for Asian (IQR = 0%-1%). Four trials omitted race and ethnicity in publications and even when information was reported, some discrepancies in terminology were identified and categories with fewer participants were often collapsed. CONCLUSION: More efforts should be done to improve transparency, accuracy, and representativeness, in publications and at a design phase, by addressing social determinants of health that historically limit the enrollment of underrepresented population.

Impact of COVID-19 on pregnancy and fetal outcomes in women with multiple sclerosis.

BACKGROUND: In the general population, maternal COVID-19 is associated with worse maternal and fetal outcomes. Two previous studies have assessed COVID-19 clinical outcomes in pregnant women with multiple sclerosis (MS), but there are no data about maternal and fetal outcomes. OBJECTIVES: In this multicenter study, we aimed to assess maternal and fetal outcomes in pregnant women with MS and COVID-19 infection. METHODS: We recruited pregnant patients with MS who contracted COVID-19 and were followed up in Italian and Turkish Centers, during 2020-2022. A control group was extracted from a previous Italian cohort. Associations between group (COVID-19 or healthy patients) and clinical outcomes (maternal complications, fetal malformations, and spontaneous abortion) were investigated with a weighted logistic regression where propensity score-based inverse probability of treatment weighting (IPTW) approach was applied for adjusting for difference in baseline confounders. RESULTS: In the multivariable analysis, COVID-19 during pregnancy was associated with a higher risk of maternal complications (odd ratio (OR) = 2.12; 95% confidence interval (CI) = 1.32-3.48; p = 0.002), while it was not associated with higher risk of spontaneous abortion and fetal malformations. CONCLUSION: Our data indicate that COVID-19 during pregnancy increases the risk of maternal complications, while it seems to have no significant impact on fetal outcomes.

Therapeutic choices and disease activity after 2 years of treatment with cladribine: An Italian multicenter study (CladStop).

BACKGROUND AND PURPOSE: Cladribine tablets, a purine analogue antimetabolite, offer a unique treatment regimen, involving short courses at the start of the first and second year, with no further treatment needed in years 3 and 4. However, comprehensive evidence regarding patient outcomes beyond the initial 24 months of cladribine treatment is limited. METHODS: This retrospective, multicenter study enrolled 204 patients with multiple sclerosis who had completed the 2-year course of cladribine treatment. The primary outcomes were therapeutic choices and clinical disease activity assessed by annualized relapse rate after the 2-year treatment course. RESULTS: A total of 204 patients were enrolled; most patients (75.4%) did not initiate new treatments in the 12 months postcladribine. The study found a significant reduction in annualized relapse rate at the 12-month follow-up after cladribine completion compared to the year prior to starting therapy (0.07 ± 0.25 vs. 0.82 ± 0.80, p < 0.001). Furthermore, patients with relapses during cladribine treatment were more likely to start new therapies, whereas older patients were less likely. The safety profile of cladribine was favorable, with lymphopenia being the primary registered adverse event. CONCLUSIONS: This study provides insights into therapeutic choices and disease activity following cladribine treatment. It highlights cladribine's effectiveness in reducing relapse rates and disability progression, reaffirming its favorable safety profile. Real-world data, aligned with previous reports, draw attention to ocrelizumab and natalizumab as common choices after cladribine. However, larger, prospective studies for validation and a more comprehensive understanding of cladribine's long-term impact are necessary.

Clinical and MRI measures to identify non-acute MOG-antibody disease in adults.

MRI and clinical features of myelin oligodendrocyte glycoprotein (MOG)-antibody disease may overlap with those of other inflammatory demyelinating conditions posing diagnostic challenges, especially in non-acute phases and when serologic testing for MOG antibodies is unavailable or shows uncertain results. We aimed to identify MRI and clinical markers that differentiate non-acute MOG-antibody disease from aquaporin 4 (AQP4)-antibody neuromyelitis optica spectrum disorder and relapsing remitting multiple sclerosis, guiding in the identification of patients with MOG-antibody disease in clinical practice. In this cross-sectional retrospective study, data from 16 MAGNIMS centres were included. Data collection and analyses were conducted from 2019 to 2021. Inclusion criteria were: diagnosis of MOG-antibody disease; AQP4-neuromyelitis optica spectrum disorder and multiple sclerosis; brain and cord MRI at least 6 months from relapse; and Expanded Disability Status Scale (EDSS) score on the day of MRI. Brain white matter T2 lesions, T1-hypointense lesions, cortical and cord lesions were identified. Random forest models were constructed to classify patients as MOG-antibody disease/AQP4-neuromyelitis optica spectrum disorder/multiple sclerosis; a leave one out cross-validation procedure assessed the performance of the models. Based on the best discriminators between diseases, we proposed a guide to target investigations for MOG-antibody disease. One hundred and sixty-two patients with MOG-antibody disease [99 females, mean age: 41 (±14) years, median EDSS: 2 (0-7.5)], 162 with AQP4-neuromyelitis optica spectrum disorder [132 females, mean age: 51 (±14) years, median EDSS: 3.5 (0-8)], 189 with multiple sclerosis (132 females, mean age: 40 (±10) years, median EDSS: 2 (0-8)] and 152 healthy controls (91 females) were studied. In young patients (<34 years), with low disability (EDSS < 3), the absence of Dawson's fingers, temporal lobe lesions and longitudinally extensive lesions in the cervical cord pointed towards a diagnosis of MOG-antibody disease instead of the other two diseases (accuracy: 76%, sensitivity: 81%, specificity: 84%, P < 0.001). In these non-acute patients, the number of brain lesions < 6 predicted MOG-antibody disease versus multiple sclerosis (accuracy: 83%, sensitivity: 82%, specificity: 83%, P < 0.001). An EDSS < 3 and the absence of longitudinally extensive lesions in the cervical cord predicted MOG-antibody disease versus AQP4-neuromyelitis optica spectrum disorder (accuracy: 76%, sensitivity: 89%, specificity: 62%, P < 0.001). A workflow with sequential tests and supporting features is proposed to guide better identification of patients with MOG-antibody disease. Adult patients with non-acute MOG-antibody disease showed distinctive clinical and MRI features when compared to AQP4-neuromyelitis optica spectrum disorder and multiple sclerosis. A careful inspection of the morphology of brain and cord lesions together with clinical information can guide further analyses towards the diagnosis of MOG-antibody disease in clinical practice.

Heterogeneity on long-term disability trajectories in patients with secondary progressive MS: a latent class analysis from Big MS Data network.

BACKGROUND: Over the decades, several natural history studies on patients with primary (PPMS) or secondary progressive multiple sclerosis (SPMS) were reported from international registries. In PPMS, a consistent heterogeneity on long-term disability trajectories was demonstrated. The aim of this study was to identify subgroups of patients with SPMS with similar longitudinal trajectories of disability over time. METHODS: All patients with MS collected within Big MS registries who received an SPMS diagnosis from physicians (cohort 1) or satisfied the Lorscheider criteria (cohort 2) were considered. Longitudinal Expanded Disability Status Scale (EDSS) scores were modelled by a latent class growth analysis (LCGA), using a non-linear function of time from the first EDSS visit in the range 3-4. RESULTS: A total of 3613 patients with SPMS were included in the cohort 1. LCGA detected three different subgroups of patients with a mild (n=1297; 35.9%), a moderate (n=1936; 53.6%) and a severe (n=380; 10.5%) disability trajectory. Median time to EDSS 6 was 12.1, 5.0 and 1.7 years, for the three groups, respectively; the probability to reach EDSS 6 at 8 years was 14.4%, 78.4% and 98.3%, respectively. Similar results were found among 7613 patients satisfying the Lorscheider criteria. CONCLUSIONS: Contrary to previous interpretations, patients with SPMS progress at greatly different rates. Our identification of distinct trajectories can guide better patient selection in future phase 3 SPMS clinical trials. Additionally, distinct trajectories could reflect heterogeneous pathological mechanisms of progression.

Assessing heterogeneity of treatment effect in multiple sclerosis trials.

Multiple sclerosis (MS) is heterogeneous with respect to outcomes, and evaluating possible heterogeneity of treatment effect (HTE) is of high interest. HTE is non-random variation in the magnitude of a treatment effect on a clinical outcome across levels of a covariate (i.e. a patient attribute or set of attributes). Multiple statistical techniques can evaluate HTE. The simplest but most bias-prone is conventional one variable-at-a-time subgroup analysis. Recently, multivariable predictive approaches have been promoted to provide more patient-centered results, by accounting for multiple relevant attributes simultaneously. We review approaches used to estimate HTE in clinical trials of MS.

Enhancing diversity of clinical trial populations in multiple sclerosis.

BACKGROUND: Demographic characteristics, social determinants of health (SDoH), health inequities, and health disparities substantially influence the general and disease-specific health outcomes of people with multiple sclerosis (MS). Participants in clinical trials do not represent all people with MS treated in practice. OBJECTIVE: To provide recommendations for enhancing diversity and inclusion in clinical trials in MS. METHODS: We held an international workshop under the Auspices of the International Advisory Committee on Clinical Trials in MS (the "Committee") to develop recommendations regarding diversity and inclusivity of participants of clinical trials in MS. Workshop attendees included members of the Committee as well as external participants. External participants were selected based on expertise in trials, SDoH, health equity and regulatory science, and diversity with respect to gender, race, ethnicity, and geography. RESULTS: Recommendations include use of diversity plans, community engagement and education, cultural competency training, biologically justified rather than templated eligibility criteria, adaptive designs that allow broadening of eligibility criteria over the course of a trial, and logistical and practical adjustments to reduce study participant burden. Investigators should report demographic and SDoH characteristics of participants. CONCLUSION: These recommendations provide sponsors and investigators with methods of improving diversity and inclusivity of clinical trial populations in MS.

Enhancing involvement of people with multiple sclerosis in clinical trial design.

BACKGROUND: Although often overlooked, patient and public involvement (PPI) is vital when considering the design and delivery of complex and adaptive clinical trial designs for chronic health conditions such as multiple sclerosis (MS). METHODS: We conducted a rapid review to assess current status of PPI in the design and conduct of clinical trials in MS over the last 5 years. We provide a case study describing PPI in the development of a platform clinical trial in progressive MS. RESULTS: We identified only eight unique clinical trials that described PPI as part of articles or protocols; nearly, all were linked with funders who encourage or mandate PPI in health research. The OCTOPUS trial was co-designed with people affected by MS. They were central to every aspect from forming part of a governance group shaping the direction and strategy, to the working groups for treatment selection, trial design and delivery. They led the PPI strategy which enabled a more accessible, acceptable and inclusive design. CONCLUSION: Active, meaningful PPI in clinical trial design increases the quality and relevance of studies and the likelihood of impact for the patient community. We offer recommendations for enhancing PPI in future MS clinical trials.

Do the current MS clinical course descriptors need to change and if so how? A survey of the MS community.

BACKGROUND AND OBJECTIVES: The current clinical course descriptors of multiple sclerosis (MS) include a combination of clinical and magnetic resonance imaging (MRI) features. Recently there has been a growing call to base these descriptors more firmly on biological mechanisms. We investigated the implications of proposing a new mechanism-driven framework for describing MS. METHODS: In a web-based survey, multiple stakeholders rated the need to change current MS clinical course descriptors, the definitions of disease course and their value in clinical practice and related topics. RESULTS: We received 502 responses across 49 countries. In all, 77% of the survey respondents supported changing the current MS clinical course descriptors. They preferred a framework that informs treatment decisions, aids the design and conduct of clinical trials, allows patients to understand their disease, and links disease mechanisms and clinical expression of disease. Clinical validation before dissemination and ease of communication to patients were rated as the most important aspects to consider when developing any new framework for describing MS. CONCLUSION: A majority of MS stakeholders agreed that the current MS clinical course descriptors need to change. Any change process will need to engage a wide range of affected stakeholders and be guided by foundational principles.

Improving the efficiency of clinical trials in multiple sclerosis.

BACKGROUND: Phase 3 clinical trials for disease-modifying therapies in relapsing-remitting multiple sclerosis (RRMS) have utilized a limited number of conventional designs with a high degree of success. However, these designs limit the types of questions that can be addressed, and the time and cost required. Moreover, trials involving people with progressive multiple sclerosis (MS) have been less successful. OBJECTIVE: The objective of this paper is to discuss complex innovative trial designs, intermediate and composite outcomes and to improve the efficiency of trial design in MS and broaden questions that can be addressed, particularly as applied to progressive MS. METHODS: We held an international workshop with experts in clinical trial design. RESULTS: Recommendations include increasing the use of complex innovative designs, developing biomarkers to enrich progressive MS trial populations, prioritize intermediate outcomes for further development that target therapeutic mechanisms of action other than peripherally mediated inflammation, investigate acceptability to people with MS of data linkage for studying long-term outcomes of clinical trials, use Bayesian designs to potentially reduce sample sizes required for pediatric trials, and provide sustained funding for platform trials and registries that can support pragmatic trials. CONCLUSION: Novel trial designs and further development of intermediate outcomes may improve clinical trial efficiency in MS and address novel therapeutic questions.

Efficacy of innovative therapies in myasthenia gravis: A systematic review, meta-analysis and network meta-analysis.

BACKGROUND AND PURPOSE: Therapy for myasthenia gravis (MG) is undergoing a profound change, with new treatments being tested. These include complement inhibitors and neonatal Fc receptor (FcRn) blockers. The aim of this study was to perform a meta-analysis and network meta-analysis of randomized and placebo-controlled trials of innovative therapies in MG with available efficacy data. METHODS: We assessed statistical heterogeneity across trials based on the Cochrane Q test and I2 values, and mean differences were pooled using the random-effects model. Treatment efficacy was assessed after 26 weeks of eculizumab and ravulizumab, 28 days of efgartigimod, 43 days of rozanolixizumab, 12 weeks of zilucoplan, and 16, 24 or 52 weeks of rituximab treatment. RESULTS: We observed an overall mean Myasthenia Gravis-Activities of Daily Living scale (MG-ADL) score change of -2.17 points (95% confidence interval [CI] -2.67, -1.67; p < 0.001) as compared to placebo. No significant difference emerged between complement inhibitors and anti-FcRn treatment (p = 0.16). The change in Quantitative Myasthenia Gravis scale (QMG) score was -3.46 (95% CI -4.53, -2.39; p < 0.001), with a higher reduction with FcRns (-4.78 vs. -2.60; p < 0.001). Rituximab did not significantly improve the MG-ADL (-0.92 [95% CI -2.24, 0.39]; p = 0.17) or QMG scores (-1.9 [95% CI -3.97, 0.18]; p = 0.07). In the network meta-analysis, efgartigimod had the highest probability of being the best treatment, followed by rozanolixizumab. CONCLUSION: Anti-complement and FcRn treatments both proved to be effective in MG patients, whereas rituximab did not show a significant benefit for patients. Within the limitations of this meta-analysis, including efficacy time points, FcRn treatments showed a greater effect on QMG score in the short term. Real-life studies with long-term measurements are needed to confirm our results.

Reduction in grey matter atrophy in patients with relapsing multiple sclerosis following treatment with cladribine tablets.

BACKGROUND AND PURPOSE: Measures of atrophy in the whole brain can be used to reliably assess treatment effect in clinical trials of patients with multiple sclerosis (MS). Trials assessing the effect of treatment on grey matter (GM) and white matter (WM) atrophy are very informative, but hindered by technical limitations. This study aimed to measure GM and WM volume changes, using a robust longitudinal method, in patients with relapsing MS randomized to cladribine tablets 3.5 mg/kg or placebo in the CLARITY study. METHODS: We analysed T1-weighted magnetic resonance sequences using SIENA-XL, from 0 to 6 months (cladribine, n = 267; placebo, n = 265) and 6 to 24 months (cladribine, n = 184; placebo, n = 186). Mean percentage GM and WM volume changes (PGMVC and PWMVC) were compared using a mixed-effect model. RESULTS: More GM and WM volume loss was found in patients taking cladribine versus those taking placebo in the first 6 months of treatment (PGMVC: cladribine: -0.53 vs. placebo: -0.25 [p = 0.045]; PWMVC: cladribine: -0.49 vs. placebo: -0.34 [p = 0.137]), probably due to pseudoatrophy. However, over the period 6 to 24 months, GM volume loss was significantly lower in patients on cladribine than in those on placebo (PGMVC: cladribine: -0.90 vs. placebo: -1.27 [p = 0.026]). In this period, volume changes in WM were similar in the two treatment arms (p = 0.52). CONCLUSIONS: After a short period of pseudoatrophy, treatment with cladribine 3.5 mg/kg significantly reduced GM atrophy in comparison with placebo. This supports the relevance of GM damage in MS and may have important implications for physical and cognitive disability progression.

Antibody response elicited by the SARS-CoV-2 vaccine booster in patients with multiple sclerosis: Who gains from it?

BACKGROUND AND PURPOSE: Although two doses of COVID-19 vaccine elicited a protective humoral response in most persons with multiple sclerosis (pwMS), a significant group of them treated with immunosuppressive disease-modifying therapies (DMTs) showed less efficient responses. METHODS: This prospective multicenter observational study evaluates differences in immune response after a third vaccine dose in pwMS. RESULTS: Four hundred seventy-three pwMS were analyzed. Compared to untreated patients, there was a 50-fold decrease (95% confidence interval [CI] = 14.3-100.0, p < 0.001) in serum SARS-CoV-2 antibody levels in those on rituximab, a 20-fold decrease (95% CI = 8.3-50.0, p < 0.001) in those on ocrelizumab, and a 2.3-fold decrease (95% CI = 1.2-4.6, p = 0.015) in those on fingolimod. As compared to the antibody levels after the second vaccine dose, patients on the anti-CD20 drugs rituximab and ocrelizumab showed a 2.3-fold lower gain (95% CI = 1.4-3.8, p = 0.001), whereas those on fingolimod showed a 1.7-fold higher gain (95% CI = 1.1-2.7, p = 0.012), compared to patients treated with other DMTs. CONCLUSIONS: All pwMS increased their serum SARS-CoV-2 antibody levels after the third vaccine dose. The mean antibody values of patients treated with ocrelizumab/rituximab remained well below the empirical "protective threshold" for risk of infection identified in the CovaXiMS study (>659 binding antibody units/mL), whereas for patients treated with fingolimod this value was significantly closer to the cutoff.

Is the effect of drugs in progressive MS only due to an effect on inflammation? A subgroup meta-analysis of randomised trials.

BACKGROUND: It is unclear whether drugs approved for the treatment of progressive multiple sclerosis (PMS) are effective in disability progression only because of their effect on the inflammatory component of the disease. OBJECTIVE: This meta-analysis aimed to evaluate whether the benefits of PMS treatments are mediated by its effect on the active component of the disease. METHODS: We conducted a systematic search to identify randomised, double-blind, placebo-controlled trials evaluating the efficacy of disease-modifying therapies on disability progression for primary or secondary PMS. The primary endpoint of the analysis was disability progression based on the expanded disability status scale. A subgroup meta-analysis evaluated the effects of treatment according to disease activity at baseline. RESULTS: Twelve trials (a total of 8659 PMS cases) were selected. Analysis of the included trials demonstrated that treatment benefit appears to be mainly confined to the group with active disease (hazard ratio (HR) = 0.67; 95% confidence interval (CI): 0.58-0.79) as compared to the group with inactive disease (HR = 0.90; 95% CI: 0.79-1.02, interaction test: p = 0.005). CONCLUSIONS: This study showed that the benefit of treating patients with PMS was mostly confined to those with the more active disease. Drugs targeting specific pathological processes leading to disability progression remain necessary.

Effects of teriflunomide treatment on cognitive performance and brain volume in patients with relapsing multiple sclerosis: Post hoc analysis of the TEMSO core and extension studies.

BACKGROUND: In post hoc analyses of Teriflunomide Multiple Sclerosis Oral study (TEMSO; NCT00134563), teriflunomide 14 mg significantly reduced brain volume loss (BVL) versus placebo in patients with relapsing multiple sclerosis (MS). OBJECTIVE: In this post hoc analysis of TEMSO and its long-term extension (NCT00803049), we examined the relationship between teriflunomide's effects on BVL and cognition. METHODS: We analyzed data from 709 patients who received teriflunomide 14 mg in TEMSO or its extension. The change in cognitive performance, assessed using the Paced Auditory Serial Addition Test 3 (PASAT-3), was measured in subgroups stratified by BVL over 2 years (least BVL: ⩽ 0.52%; intermediate BVL: >0.52%-2.18%; most BVL: >2.18%). BVL, MRI lesions, and relapses over 2 years were evaluated as potential mediators of the effect of teriflunomide on cognition. RESULTS: Teriflunomide 14 mg significantly improved PASAT-3 Z-scores versus placebo through year 2. In the least- and intermediate-BVL groups, significant improvements in PASAT-3 Z-score were demonstrated versus the most-BVL group over 3 years in the extension. According to the mediation analysis, 44% of the teriflunomide effect on cognition was due to effects on BVL at year 2. CONCLUSION: Teriflunomide improves cognition largely through its effects on BVL. Accelerated BVL earlier in the disease course may predict cognitive outcomes. CLINICALTRIALS.GOV IDENTIFIER: NCT00134563, NCT00803049.

Estimation of sample size in randomized controlled trials in multiple sclerosis studying annualized relapse rates: A systematic review.

BACKGROUND: In multiple sclerosis (MS) studies, the most appropriate model for the distribution of the number of relapses was shown to be the negative binomial (NB) distribution. OBJECTIVE: To determine whether the sample-size estimation (SSE) and the analysis of annualized relapse rates (ARRs) in randomized controlled trials (RCTs) were aligned and compare the SSE between normal and NB distributions. METHODS: Systematic review of phase 3 and 4 RCTs for which the primary endpoint was ARR in relapsing remitting MS published since 2008 in pre-selected major medical journals. A PubMed search was performed on 30 November 2020. We checked whether the SSE and ARR analyses were congruent. We also performed standardized (fixed α/ß, number of arms and overdispersion) SSEs using data collected from the studies. RESULTS: Twenty articles (22 studies) were selected. NB distribution (or quasi-Poisson) was used for SSE in only 7/22 studies, whereas 21/22 used it for ARR analyses. SSE relying on NB regression necessitated a smaller sample size in 21/22 of our calculations. CONCLUSION: SSE was rarely performed using the most appropriate model. However, the use of an NB model is recommended to optimize the number of included patients and to be congruent with the final analysis.