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

Patient outcomes influenced by reduced lymphocyte counts after dimethyl fumarate initiation

Objective: To examine the temporal profile of absolute and lymphocyte subset data from dimethyl fumarate (DMF) start and relationships to disease behavior. Methods: A retrospective study performed on patients with an existing diagnosis of MS and a history of DMF exposure from a single MS center. Demographic, laboratory, and corresponding clinical relapse and MRI data were recorded from baseline and in 3-4-month intervals after treatment initiation extending to 3 years. The Spearman rank coefficient and mixed-effects models were used to assess longitudinal correlations between cell counts and measures of disease activity. Results: A total of 292 patients with MS (228 women; median age at DMF initiation: 40.6 years, range: 16.1-66.7 years) were identified. An increased risk of disease activity was associated with higher absolute lymphocyte count (ALC) values at 3 months (p = 0.001, OR: 1.82) and at 6 months (p = 0.032, hazard ratio: 1.73). A reduced risk of disease evolution in patients with lower ALC values < 1,200 cells/L compared with midtier (1,210-1,800 cells/L) and the highest tertile (>1,810 cells/L) was observed (p = 0.01). Conclusions: Reductions in ALC values at months 3 and 6 after treatment initiation appear to be associated with improved clinical and radiologic outcomes. These data alone may help to provide a better understanding of both the safety and efficacy of DMF

Predicting long-term disability outcomes in patients with MS treated with teriflunomide in TEMSO

To predict long-term disability outcomes in TEMSO core (NCT00134563) and extension (NCT00803049) studies in patients with relapsing forms of MS treated with teriflunomide. Methods: A post hoc analysis was conducted in a subgroup of patients who received teriflunomide in the core study, had MRI and clinical relapse assessments at months 12 (n = 552) and 18, and entered the extension. Patients were allocated risk scores for disability worsening (DW) after 1 year of teriflunomide treatment: 0 = low risk; 1 = intermediate risk; and 2-3 = high risk, based on the occurrence of relapses (0 to 652) and/or active (new and enlarging) T 2 -weighted (T 2 w) lesions ( 643 or >3) after the 1-year MRI. Patients in the intermediate-risk group were reclassified as responders or nonresponders (low or high risk) according to relapses and T 2 w lesions on the 18-month MRI. Long-term risk (7 years) of DW was assessed by Kaplan-Meier survival curves. Results: In patients with a score of 2-3, the risk of 12-week-confirmed DW over 7 years was significantly higher vs those with a score of 0 (hazard ratio [HR] = 1.96, p = 0.0044). Patients reclassified as high risk at month 18 (18.6%) had a significantly higher risk of DW vs those in the low-risk group (81.4%; HR = 1.92; p = 0.0004). Conclusions: Over 80% of patients receiving teriflunomide were classified as low risk (responders) and had a significantly lower risk of DW than those at increased risk (nonresponders) over 7 years of follow-up in TEMSO. Close monitoring of relapses and active T 2 w lesions after short-term teriflunomide treatment predicts a differential rate of subsequent DW long term. ClinicalTrials.gov identifier: TEMSO, NCT00134563; TEMSO extension, NCT0080304

Modeling the Distribution of New MRI Cortical Lesions in Multiple Sclerosis Longitudinal Studies

Objective: Recent studies have shown the relevance of the cerebral grey matter involvement in multiple sclerosis (MS). The number of new cortical lesions (CLs), detected by specific MRI sequences, has the potential to become a new research outcome in longitudinal MS studies. Aim of this study is to define the statistical model better describing the distribution of new CLs developed over 12 and 24 months in patients with relapsing-remitting (RR) MS. Methods: Four different models were tested (the Poisson, the Negative Binomial, the zero-inflated Poisson and the zeroinflated Negative Binomial) on a group of 191 RRMS patients untreated or treated with 3 different disease modifying therapies. Sample size for clinical trials based on this new outcome measure were estimated by a bootstrap resampling technique. Results: The zero-inflated Poisson model gave the best fit, according to the Akaike criterion to the observed distribution of new CLs developed over 12 and 24 months both in each treatment group and in the whole RRMS patients group adjusting for treatment effect. Conclusions: The sample size calculations based on the zero-inflated Poisson model indicate that randomized clinical trials using this new MRI marker as an outcome are feasible

Association of NEDA-4 With No Long-term Disability Progression in Multiple Sclerosis and Comparison With NEDA-3: A Systematic Review and Meta-analysis

Esclerosis múltiple; Discapacidad; NEDA-4Esclerosi múltiple; Discapacitat; NEDA-4Multiple sclerosis; Disability; NEDA-4Background and Objectives No evidence of disease activity (NEDA)-4 has been suggested as a treatment target for disease-modifying therapy (DMT) in relapsing-remitting multiple sclerosis (RRMS). However, the ability of NEDA-4 to discriminate long-term outcomes in MS and how its performance compares with NEDA-3 remain uncertain. We conducted a systematic review and meta-analysis to evaluate (1) the association between NEDA-4 and no long-term disability progression in MS and (2) the comparative performance of NEDA-3 and NEDA-4 in predicting no long-term disability progression. Methods English-language abstracts and manuscripts were systematically searched in MEDLINE, Embase, and the Cochrane databases from January 2006 to November 2021 and reviewed independently by 2 investigators. We selected studies that assessed NEDA-4 at 1 or 2 years after DMT start and had at least 4 years of follow-up for determination of no confirmed disability progression. We conducted a meta-analysis using random-effects model to determine the pooled odds ratio (OR) for no disability progression with NEDA-4 vs EDA-4. For the comparative analysis, we selected studies that evaluated both NEDA-3 and NEDA-4 with at least 4 years of follow-up and examined the difference in the association of NEDA-3 and NEDA-4 with no disability progression. Results Five studies of 1,000 patients (3 interferon beta and 2 fingolimod) met inclusion criteria for both objectives. The median duration of follow-up was 6 years (interquartile range: 4–6 years). The prevalence of NEDA-4 ranged from 4.2% to 13.9% on interferon beta therapy and 24.9% to 25.1% on fingolimod therapy. The pooled OR for no long-term confirmed disability progression with NEDA-4 vs EDA-4 was 2.14 (95% confidence interval: 1.36–3.37; I2 = 0). We did not observe any significant difference between NEDA-4 and NEDA-3 in the comparative analyses. Discussion In patients with RRMS, NEDA-4 at 1–2 years was associated with 2 times higher odds of no long-term disability progression, at 6 years compared with EDA-4, but offered no advantage over NEDA-3

Clinical trials of disease-modifying agents in pediatric MS Opportunities, challenges, and recommendations from the IPMSSG

Objective The impetus for this consensus discussion was to recommend clinical trial designs that can deliver high-quality data for effective therapies for pediatric patients, in a reasonable timeframe, with a key focus on short- and long-term safety. Methods The International Pediatric Multiple Sclerosis Study Group convened a meeting of experts to review the advances in the understanding of pediatric-onset multiple sclerosis (MS) and the advent of clinical trials for this population. Results In the last few years, convincing evidence has emerged that the biological processes involved in MS are largely shared across the age span. As such, treatments proven efficacious for the care of adults with MS have a biological rationale for use in pediatric MS given the relapsing-remitting course at onset and high relapse frequency. There are also ethical considerations on conducting clinical trials in this age group including the use of placeb

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. © 2022 The Authors

Establishing pathological cut-offs of brain atrophy rates in multiple sclerosis

Objective To assess whether it is feasible to establish specific cut-off values able to discriminate 'physiological' or 'pathological' brain volume rates in patients with multiple sclerosis (MS). Methods The study was based on the analysis of longitudinal MRI data sets of patients with MS (n=206, 87% relapsing-remitting, 7% secondary progressive and 6% primary progressive) and healthy controls (HC; n=35). Brain atrophy rates were computed over a mean follow-up of 7.5 years (range 1-12) for patients with MS and 6.3 years (range 1-12.5) for HC with the SIENA software and expressed as annualised per cent brain volume change (PBVC/y). A weighted (on the follow-up length) receiver operating characteristic analysis and the area under the curve (AUC) were used for statistics. Results The weighted PBVC/y was -0.51±0.27% in patients with MS and -0.27±0.15% in HC (p<0.0001). There was a significant age-related difference in PBVC/y between HC older and younger than 35 years of age ( p=0.02), but not in patients with MS (p=0.8). The cutoff of PBVC/y, as measured by SIENA that could maximise the accuracy in discriminating patients with MS from HC, was -0.37%, with 67% sensitivity and 80% specificity. According to the observed distribution, values of PBVC/y as measured by SIENA that could define a pathological range were above -0.52% with 95% specificity, above -0.46% with 90% specificity and above -0.40% with 80% specificity. Conclusions Our evidence-based criteria provide values able to discriminate the presence or absence of 'pathological' brain volume loss in MS with high specificity. Such results could be of great value in a clinical setting, particularly in assessing treatment efficacy in MS

A Comprehensive Review on Copemyl(\uae)

Economic sustainability is of paramount importance in the rapidly evolving therapeutic scenario of multiple sclerosis (MS). Glatiramoids are a class of drugs whose forefather, glatiramer acetate, has been used as a disease modifying drug (DMD) in patients with MS for over 20 years. Its patent expired in 2015; new versions of such drug are nowadays available on the market, potentially contributing to lowering prices and enhancing a better allocation of economic resources. In this review, we analyze the recommendations underlying the approval of both generic drugs and biosimilars by regulatory authorities, and we provide methodological tools to contextualize the design of studies on these new classes of drugs. We examine in more detail the preclinical and clinical data of Copemyl(\uae), a new member of the glatiramoid class, focusing on its biological and immunological properties and illustrating randomized controlled trials that led to its authorization