Interferon therapy in relapsing-remitting multiple sclerosis: A systematic review and meta-analysis of the comparative trials

Interferon β and Anti-PD-1/PD-L1 Checkpoint Blockade Cooperate in NK Cell-Mediated Killing of Nasopharyngeal Carcinoma Cells

Nasopharyngeal carcinoma (NPC) is a highly malignant epithelial cancer linked to EBV infection. Addition of interferon-β (IFNβ) to chemo- and radiochemotherapy has led to survival rates >90% in children and adolescents. As NPC cells are sensitive to apoptosis via tumor necrosis factor-related apoptosis inducing ligand (TRAIL), we explored the role of TRAIL and IFNβ in the killing of NPC cells by natural killer (NK) cells. NPC cells, including cells of a patient-derived xenograft were exposed to NK cells in the presence or absence of IFNβ. NK cells killed NPC- but not nasoepithelial cells and killing was predominately mediated via TRAIL. Incubation of NK cells with IFNβ increased cytotoxicity against NPC cells. Concomitant incubation of NK- and NPC cells with IFNβ before coculture reduced cytotoxicity and could be overcome by blocking the PD-1/PD-L1 axis leading to the release of intracellular TRAIL from NK cells. In conclusion, combination of IFNβ and anti-PD-1, augmenting cytotoxicity of NK cells against NPC cells, could be a strategy to improve NPC-directed therapy and warrants further evaluation in vivo.

The Effect of Disease Modifying Therapies on Disability Progression in Multiple Sclerosis: A Systematic Overview of Meta-Analyses

Background: Disease modifying therapy (DMT) efficacy trials make an essential contribution to the development of evidence-based clinical treatments and practices for people with multiple sclerosis (MS). Meta-analysis is a critical part of this process and provides a powerful tool to assess the effects of DMT on MS progression. However, although there have been several meta-analyses on the effect of DMT on MS disease progression, they often do not reach the same conclusions.

Objective: Our aim was to better understand and contextualize the results of meta-analyses evaluating DMT, identify differences in methodology that might explain their differing conclusions, and highlight areas for future research that will improve our ability to develop clinical recommendations.

Methods: We conducted an overview of systematic reviews with meta-analyses assessing the efficacy of DMT on disability progression in people with MS in PubMed (Medline) and the Cochrane Database of Systematic Reviews.

Results: We included 22 meta-analyses in this overview: eight general (on >3 DMT), 11 specific (on ≤3 DMT), 2 that evaluated subsets, and 1 that evaluated long-term effects. We found that there is good evidence that DMT improve short-term (≤2–3 years) disability progression outcomes relative to placebo in people with relapsing-remitting MS. However, results varied substantially between meta-analyses, and there is little evidence of their efficacy in other populations or over longer periods. The relative effects of individual DMT also remain unclear. The variance in results between meta-analyses may be related to the substantial differences in inclusion criteria, which was reflected in the limited overlap in included studies, as well as the year of meta-analysis publication. Of the 123 total unique studies included in the general meta-analyses, 77 (62.6%) were included in only one meta-analysis. This incongruence was also evident in the included DMT. Six of the 16 (37.5%) DMT evaluated in the general meta-analyses were only included in one meta-analysis.

Conclusions: Translating DMT efficacy studies into evidence-based clinical practice requires greater methodological consistency in meta-analyses, more data on the relative effects of DMT through head-to-head clinical trials, and better reporting of adverse events.

Recent developments in interferon-based therapies for multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a chronic and disabling immune-mediated disease of the central nervous system. Beta-interferons are the first approved and still the most widely used first-line disease-modifying treatment in MS.

AREAS COVERED

Here we focus on recent developments in pharmacology and delivery systems of beta-interferons, and discuss their place within current state of the art therapeutic approaches. We briefly review the clinical trials for classical and PEGylated formulations, emphasizing effectiveness, safety concerns, and tolerability. The mechanisms of action of IFN-β in view of MS pathogenesis are also debated

EXPERT OPINION

Though only modestly efficient in reducing the annualized relapse rate, beta-interferons remain a valid first-line option due to their good long-term safety profile and cost-efficacy. Moreover, they are endogenous class II cytokines essential for mounting an effective antiviral response, and they may interact with putative MS triggering factors such as Epstein-Barr virus infection and human endogenous retroviruses. Recent improvements in formulations, delivery devices and drug regimens tackle the tolerability and adherence issues frequently seen with these drugs, and scientific advances may offer means for a better selection of patients. Although a well-established immunomodulatory treatment, beta-interferons have not said their last word in the management of MS.

Interferon beta induces apoptosis in nasopharyngeal carcinoma cells via the TRAIL-signaling pathway

The combination of neoadjuvant chemotherapy, radiochemotherapy, and maintenance therapy with interferon beta (IFNβ) has led to superior results in the treatment of children and adolescents with nasopharyngeal carcinoma (NPC). However, nothing is known about the mechanism of the antitumor activity of IFNβ in NPC. Here, we investigate the role of IFNβ on apoptosis in NPC cells. Six NPC cell lines, one patient-derived NPC xenograft (PDX) and one SV40-transformed nasoepithelial cell line were used. Induction of apoptosis by IFNβ was measured by flow cytometric analysis of subG1-DNA-content, Hoechst 33258 staining and activation of caspase-3. Dissection of death ligand signaling pathways included measuring surface expression of its components by flow cytometry, activation by death ligands and neutralization with specific antibodies and siRNA. IFNβ induced apoptosis at concentrations achievable in humans in five of six NPC cell lines and in PDX cells but not in nasoepithelial cells. Inhibition of caspases-3 and −8 abrogated this effect suggesting IFNβ promoted apoptosis through the extrinsic pathway. IFNβ induced surface expression of TRAIL and TRAIL-R2 and the addition of an anti-TRAIL-antibody or transfection with TRAIL-siRNA blocked IFNβ-induced apoptosis. No induction of TRAIL-expression was noted in the IFNβ-resistant cell line. In conclusion, IFNβ leads to apoptosis in NPC cells in an autocrine way via the induction of TRAIL expression and subsequent activation of the TRAIL-signaling pathway. The mechanism described could at least partly explain the clinical benefit of IFNβ in the treatment of NPC. Further studies in a mouse-xenograft model are warranted to substantiate this effect in vivo.

Adherence to subcutaneous interferon beta-1a treatment using an electronic injection device: a prospective open-label Scandinavian noninterventional study (the ScanSmart study)

BACKGROUND

Disease modifying drugs help control the course of relapsing remitting multiple sclerosis (RRMS); however, good adherence is needed for long-term outcomes.

OBJECTIVE

To evaluate patient adherence to treatment with subcutaneous interferon beta-1a using RebiSmart^® and assess injection-site reactions and treatment satisfaction.

METHODS

This prospective, single-arm, open-label, noninterventional multicenter Phase IV trial included disease modifying drug-experienced mobile patients with RRMS. Adherence was measured over 12 weeks. Items 13-23, 35, 37, and 38 of the Multiple Sclerosis Treatment Concerns Questionnaire (injection-site reactions and treatment satisfaction) were recorded at 12 weeks.

RESULTS

Sixty patients were recruited (mean age 43.7 [±SD 7.9] years; 83% female; mean years since multiple sclerosis diagnosis 6.7 [SD 4.5]). Adherence data were obtained in 54 patients only due to technical problems with six devices. Over 12 weeks, 89% (n=48) of patients had ≥90% adherence to treatment. Most patients experienced mild influenza-like symptoms and injection-site reactions, and global side effects were minimal. Most patients (78%) rated the convenience as the most important aspect of the device, and most experienced no or mild pain.

CONCLUSION

RRMS patients treated with subcutaneous interferon beta-1a, administered with RebiSmart, demonstrated generally good adherence, and the treatment was generally well tolerated.

Long-term safety and real-world effectiveness of fingolimod in relapsing multiple sclerosis

With a growing number of disease-modifying therapies becoming available for relapsing multiple sclerosis, there is an important need to gather real-world evidence data regarding long-term treatment effectiveness and safety in unselected patient populations. Although not providing as high a level of evidence as randomized controlled trials, and prone to bias, real-world studies from observational studies or registries nevertheless provide crucial information on real-world outcomes of a given therapy. In addition, evaluation of treatment satisfaction and impact on quality of life are increasingly regarded as complementary outcome measures. Fingolimod was the first oral disease-modifying therapy approved for relapsing multiple sclerosis. This review aims to summarize current knowledge on the long-term effectiveness and safety outcomes of multiple sclerosis patients on fingolimod. Impact on treatment satisfaction and quality of life will be discussed according to available data.

Power-up: A Reanalysis of 'Power Failure' in Neuroscience Using Mixture Modeling

Recently, evidence for endemically low statistical power has cast neuroscience findings into doubt. If low statistical power plagues neuroscience, then this reduces confidence in the reported effects. However, if statistical power is not uniformly low, then such blanket mistrust might not be warranted. Here, we provide a different perspective on this issue, analyzing data from an influential study reporting a median power of 21% across 49 meta-analyses (Button et al., 2013). We demonstrate, using Gaussian mixture modeling, that the sample of 730 studies included in that analysis comprises several subcomponents so the use of a single summary statistic is insufficient to characterize the nature of the distribution. We find that statistical power is extremely low for studies included in meta-analyses that reported a null result and that it varies substantially across subfields of neuroscience, with particularly low power in candidate gene association studies. Therefore, whereas power in neuroscience remains a critical issue, the notion that studies are systematically underpowered is not the full story: low power is far from a universal problem.SIGNIFICANCE STATEMENT Recently, researchers across the biomedical and psychological sciences have become concerned with the reliability of results. One marker for reliability is statistical power: the probability of finding a statistically significant result given that the effect exists. Previous evidence suggests that statistical power is low across the field of neuroscience. Our results present a more comprehensive picture of statistical power in neuroscience: on average, studies are indeed underpowered-some very seriously so-but many studies show acceptable or even exemplary statistical power. We show that this heterogeneity in statistical power is common across most subfields in neuroscience. This new, more nuanced picture of statistical power in neuroscience could affect not only scientific understanding, but potentially policy and funding decisions for neuroscience research.

Daclizumab for the treatment of relapsing-remitting multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a common inflammatory disease of the central nervous system. Over the last two decades, the number of therapeutic options for the treatment of relapsing remitting MS (RRMS) has been constantly growing, providing new treatment options to patients. Areas covered: Herein, the authors review the recently approved monoclonal antibody daclizumab for the treatment of RRMS. Based on original articles, they discuss its mode of action and evaluate its efficacy and safety profile compared to other available agents. Expert opinion: The IL-2 receptor modulator daclizumab is a new highly effective agent for the treatment of RRMS with novel immunomodulatory properties. Compared to interferon-beta i.m., daclizumab is more effective in reducing relapse rates and MRI activity. However, its use is limited by the risk of autoimmune disorders and hepatotoxicity. Similar to other monoclonal antibodies for RRMS, therapy with daclizumab needs a strict preselection and monitoring of patients based on individual risk benefit assessment. Given its substantial effectiveness, daclizumab can be an attractive option for patients with highly active MS.

Comparative effectiveness of interferons in relapsing-remitting multiple sclerosis: a meta-analysis of real-world studies

BACKGROUND

Differences between interferons have been evaluated for over 20 years. While randomized controlled trial (RCT) data is mainly used for assessments and strong data for causal inferences, it does not necessarily reflect everyday practice. Real-world data may provide additional information.

PURPOSE

To assess the results, quality, and representativeness of observational studies directly comparing interferons (IFNs) in RRMS.

METHODS

Medline and Embase were searched for observational studies comparing IFN-beta-1a 30 mcg IM (Avonex ¹ ), IFN-beta-1a 44 mcg SC (Rebif ² ) and/or IFN-beta-1b 250 mcg SC (Betaseron ³ ). Outcomes included annualized relapse rate (ARR), proportions relapse free, confirmed progression free, treatment persistence, and neutralizing antibodies rates (NABs) measured up to 5 years of treatment. Data was combined using random effects meta-analyses. Categorical values were analyzed using chi-squared and Mann-Whitney tests.

RESULTS

Thirty-six studies examining 32,026 patients (72.5% females, age = 39.2 ± 3.7 years, disease duration = 5.6 ± 2.0 years) were identified. Thirty-three studies investigated IFN-beta-1a IM (N = 11,925), 30 IFN-beta-1a SC (N = 10,684) and 34 IFN-beta-1b SC (N = 9417). Baseline ARRs were similar (1.37 ± 0.35, 1.51 ± 0.27 and 1.55 ± 0.23, respectively; P = .101) as were EDSS scores (2.24 ± 0.39, 2.33 ± 0.30, 2.55 ± 0.38; P = .070) and >75% were naïve to IFNs. On treatment, ARRs were comparable (IFN-beta-1a IM 0.52 ± 0.27, IFN-beta-1a SC 0.51 ± 0.24, IFN-beta-1b SC 0.55 ± 0.23; P = .595). Proportions of relapse-free patients were similar between drugs (P > .05 for all data points), except that IFN-beta-1a SC was superior to IFN-beta-1b SC in years 3-5 (all P ≤ .001). After 1 year, EDSS scores were comparable; after 2 years, IFN-beta-1a IM and IFN-beta-1a SC incurred less disease progression than IFN-beta-1b SC (P < .02). Confirmed progression-free rates and persistence were similar over 5 years. Fewer patients developed NABs with IFN-beta-1a IM (4.7 ± 1.5%) versus IFN-beta-1a SC (21.4 ± 2.8%) (P < 0.001) or IFN-beta-1b SC (32.2% ± 3.3%) (P < .001).

CONCLUSIONS

In this comprehensive meta-analysis of real-world studies in RRMS, IFN-beta-1a IM, IFN-beta-1a SC and IFN-beta-1b SC had similar clinical profiles. When selecting an IFN, practitioners should consider observational data in their decision making process.

Efficacy of immunomodulatory therapy with interferon-β or glatiramer acetate on multiple sclerosis-associated uveitis

AIM

To analyse the role of interferon-β or glatiramer acetate in reducing the inflammatory episodes of intra-ocular inflammation in multiple sclerosis-associated uveitis.

METHOD

A study was conducted on a non-randomised, retrospective case series of 13 patients with proven multiple sclerosis and uveitis (minimum follow-up, 12 months). All patients were given immunomodulatory treatment (interferon-β or glatiramer acetate) to control the course of the multiple sclerosis. Patients were compared to themselves before initiating the treatment, in order to assess the difference in uveitis episodes. The main outcome measurements were the number of uveitis episodes with/without immunomodulatory treatment.

RESULTS

Uveitis was bilateral in 10 (77%) out of 13 patients. Intermediate uveitis was observed in 11 patients, retinal vasculitis in 3 patients, and one patient was classified as a posterior uveitis. The patients had a mean of 4.15±3.1 episodes of uveitis (range 1-10) during the follow-up period (148.6±84.3 months). When compared to their pre-treatment status, patients on treatment with interferon-β or glatiramer acetate showed a significant decrease of 0.36 episodes of ocular inflammation per year (P=.02). Mild side effects related to immunomodulatory treatment were observed in 6 (46%) patients, 3 (23%) patients with a flu-like syndrome, and 3 (23%) patients with a skin rash.

CONCLUSIONS

Interferon β or glatiramer acetate could be effective in reducing the uveitis episodes in patients with multiple sclerosis-associated uveitis, and was well tolerated in most patients.

Interferons-beta versus glatiramer acetate for relapsing-remitting multiple sclerosis

BACKGROUND

Interferons-beta (IFNs-beta) and glatiramer acetate (GA) were the first two disease-modifying therapies (DMTs) approved 20 years ago for the treatment of multiple sclerosis (MS). DMTs' prescription rates as first or switching therapies and their costs have both increased substantially over the past decade. As more DMTs become available, the choice of a specific DMT should reflect the risk/benefit profile, as well as the impact on quality of life. As MS cohorts enrolled in different studies can vary significantly, head-to-head trials are considered the best approach for gaining objective reliable data when two different drugs are compared. The purpose of this systematic review is to summarise available evidence on the comparative effectiveness of IFNs-beta and GA on disease course through the analysis of head-to-head trials.This is an update of the Cochrane review 'Interferons-beta versus glatiramer acetate for relapsing-remitting multiple sclerosis' (first published in the Cochrane Library 2014, Issue 7).

OBJECTIVES

To assess whether IFNs-beta and GA differ in terms of safety and efficacy in the treatment of people with relapsing-remitting (RR) MS.

SEARCH METHODS

We searched the Trials Register of the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group (08 August 2016) and the reference lists of retrieved articles. We contacted authors and pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing directly IFNs-beta versus GA in study participants affected by RRMS.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

Six trials were included and five trials contributed to this review with data. A total of 2904 participants were randomly assigned to IFNs (1704) and GA (1200). The treatment duration was three years for one study, two years for the other four RCTs while one study was stopped early (after one year). The IFNs analysed in comparison with GA were IFN-beta 1b 250 mcg (two trials, 933 participants), IFN-beta 1a 44 mcg (three trials, 466 participants) and IFN-beta 1a 30 mcg (two trials, 305 participants). Enrolled participants were affected by active RRMS. All studies were at high risk for attrition bias. Three trials are still ongoing, one of them completed.Both therapies showed similar clinical efficacy at 24 months, given the primary outcome variables (number of participants with relapse (risk ratio (RR) 1.04, 95% confidence interval (CI) 0.87 to 1.24) or progression (RR 1.11, 95% CI 0.91 to 1.35). However at 36 months, evidence from a single study suggests that relapse rates were higher in the group given IFNs than in the GA group (RR 1.40, 95% CI 1.13 to 1.74, P value 0.002).Secondary magnetic resonance imaging (MRI) outcomes analysis showed that effects on new or enlarging T2- or new contrast-enhancing T1 lesions at 24 months were similar (mean difference (MD) -0.15, 95% CI -0.68 to 0.39, and MD -0.14, 95% CI -0.30 to 0.02, respectively). However, the reduction in T2- and T1-weighted lesion volume was significantly greater in the groups given IFNs than in the GA groups (MD -0.58, 95% CI -0.99 to -0.18, P value 0.004, and MD -0.20, 95% CI -0.33 to -0.07, P value 0.003, respectively).The number of participants who dropped out of the study because of adverse events was similar in the two groups (RR 0.95, 95% CI 0.64 to 1.40).The quality of evidence for primary outcomes was judged as moderate for clinical end points, but for safety and some MRI outcomes (number of active T2 lesions), quality was judged as low.

AUTHORS' CONCLUSIONS

The effects of IFNs-beta and GA in the treatment of people with RRMS, including clinical (e.g. people with relapse, risk to progression) and MRI (Gd-enhancing lesions) measures, seem to be similar or to show only small differences. When MRI lesion load accrual is considered, the effect of the two treatments differs, in that IFNs-beta were found to limit the increase in lesion burden as compared with GA. Evidence was insufficient for a comparison of the effects of the two treatments on patient-reported outcomes, such as quality-of-life measures.

Long-term efficacy and safety of intramuscular interferon beta-1a: Randomized postmarketing trial of two dosing regimens in Japanese patients with relapsing-remitting multiple sclerosis

OBJECTIVES

To evaluate the efficacy and safety of 2 years of treatment with intramuscular interferon beta-1a (IM IFN beta-1a) in Japanese patients with relapsing-remitting multiple sclerosis, with an exploratory analysis of the impact of initial dose titration on tolerability.

METHODS

Japanese patients with relapsing-remitting multiple sclerosis were randomized to receive IM IFN beta-1a at dosages of either 30mcg once weekly (full-dose group, n=50) or 15mcg once weekly for 2 weeks then 30mcg once weekly thereafter (titration group, n=50). Key outcomes included annualized relapse rate (ARR) at 2 years (primary endpoint), change in disability measured using the Expanded Disability Status Scale (EDSS), safety, and tolerability.

RESULTS

The ARR (95% CI) decreased from 1.540 (1.381-1.718) at baseline to 0.371 (0.240-0.571) at Year 1 and 0.351 (0.244-0.503) at Year 2. EDSS improvements were apparent from Week 24; the mean change from baseline EDSS score (2.1) at Year 2 was -0.34 (P=0.004). The most frequently reported adverse events were influenza-like illness (92%), nasopharyngitis (57%), relapse of multiple sclerosis (51%), and injection-site reaction (30%). The overall incidence and severity of influenza-like symptoms were similar in the full-dose group and titration group; only 1 participant, in the full-dose group (2%), experienced severe influenza-like symptoms. However, the incidence of influenza-like symptoms was slightly reduced at earlier timepoints in the titration group.

CONCLUSIONS

The results of this 2-year study demonstrate that IM IFN beta-1a can be used effectively and safely in Japanese patients with relapsing-remitting multiple sclerosis for an extended period of time.

Impact of a switch to fingolimod versus staying on glatiramer acetate or beta interferons on patient- and physician-reported outcomes in relapsing multiple sclerosis: post hoc analyses of the EPOC trial

Background

The Evaluate Patient OutComes (EPOC) study assessed physician- and patient-reported outcomes in individuals with relapsing multiple sclerosis who switched directly from injectable disease-modifying therapy (iDMT; glatiramer acetate, intramuscular or subcutaneous interferon beta-1a, or interferon beta-1b) to once-daily, oral fingolimod. Post hoc analyses evaluated the impact of a switch to fingolimod versus staying on each of the four individual iDMTs.

Methods

Overall, 1053 patients were randomized 3:1 to switch to fingolimod or remain on iDMT. The primary endpoint was the change in Treatment Satisfaction Questionnaire for Medication (TSQM) Global Satisfaction score. Secondary endpoints included changes in scores for TSQM Effectiveness, Side Effects and Convenience subscales, Beck Depression Inventory-II (BDI-II), Fatigue Severity Scale (FSS), Patient-Reported Outcome Indices for Multiple Sclerosis (PRIMUS) Activities, 36-item Short-Form Health Survey (SF-36) Mental Component Summary (MCS) and Physical Component Summary (PCS) and mean investigator-reported Clinical Global Impressions of Improvement (CGI-I). All outcomes were evaluated after 6 months of treatment.

Results

Changes in TSQM Global Satisfaction scores were superior after a switch to fingolimod when compared with scores in patients remaining on any of the iDMTs (all p <0.001). Likewise, all TSQM subscale scores improved following a switch to fingolimod (all p <0.001), except when compared with glatiramer acetate for the TSQM Side Effects subscale (p = 0.111). FSS scores were found to be superior for fingolimod versus remaining on subcutaneous interferon beta-1a and interferon beta-1b, BDI-II scores were significantly improved for fingolimod except for the comparison with intramuscular interferon beta-1a, and SF-36 scores were superior with fingolimod compared with remaining on interferon beta-1b (MCS and PCS; p = 0.030 and p = 0.022, respectively) and subcutaneous interferon beta-1a (PCS only; p = 0.024). Mean CGI-I scores were superior with fingolimod when compared with continuing treatment with any of the iDMTs (all p <0.001).

Conclusions

After 6 months, a switch to fingolimod showed superiority compared with remaining on each iDMT for a range of patient- and physician-reported outcomes, including global satisfaction with treatment.

Trial registration

ClinicalTrials.gov NCT01216072.

Outcomes of switching directly to oral fingolimod from injectable therapies: Results of the randomized, open-label, multicenter, Evaluate Patient OutComes (EPOC) study in relapsing multiple sclerosis

BACKGROUND

The Evaluate Patient OutComes (ClinicalTrials.gov Identifier: NCT01216072) study was conducted in North America to assess patient- and physician-reported treatment satisfaction in patients with relapsing multiple sclerosis (MS) who received oral fingolimod for 6 months after switching from an injectable disease-modifying therapy (iDMT), without an intervening washout.

METHODS

In this open-label, multicenter study, patients were randomized 3:1 to once-daily fingolimod 0.5mg or iDMT. The primary study objective was to evaluate differences in satisfaction measured using the Treatment Satisfaction Questionnaire for Medication v1.4.

RESULTS

Of 1053 patients randomized, 790 patients received fingolimod and 263 patients received iDMT. Treatment satisfaction improved significantly in patients who switched to fingolimod compared with those who continued iDMT. Patients also reported significant improvements in health-related quality of life, reduced depression, and reduced fatigue severity after a switch to fingolimod. No difference between the treatment groups was detected on the Patient Reported Indices for MS Activities scale. The safety profile of fingolimod was consistent with that reported in the pivotal phase 3 studies. The most commonly reported adverse events were more prevalent in patients who switched to fingolimod than in those who continued iDMT (headache: 12% vs 3%; fatigue: 12% vs 6%). No significant relationship between lymphocyte counts and infection rates was observed and there was no evidence of additive immune-system effects, which might be expected when switching to a different class of immunomodulatory therapy with no intervening washout.

CONCLUSION

Patients who switched from iDMT to fingolimod had significant improvements in most self-reported outcomes compared with those who continued iDMT.

Treatment discontinuation and disease progression with injectable disease-modifying therapies: findings from the north american research committee on multiple sclerosis database

Injectable first-line disease-modifying therapies (DMTs) for multiple sclerosis (MS) are generally prescribed for continuous use. Accordingly, the various factors that influence patient persistence with treatment and that can lead some patients to switch medications or discontinue treatment may affect clinical outcomes. Using data from the North American Research Committee on Multiple Sclerosis (NARCOMS) database, this study evaluated participants' reasons for discontinuation of injectable DMTs as well as the relationship between staying on therapy and sustained patient-reported disease progression and annualized relapse rates. Participants selected their reason(s) for discontinuation from among 16 possible options covering the categories of efficacy, safety, tolerability, and burden, with multiple responses permitted. Both unadjusted data and data adjusted for baseline age, disease duration, disability, and sex were evaluated. Discontinuation profiles varied among DMTs. Participants on intramuscular interferon beta-1a (IM IFNβ-1a) and glatiramer acetate (GA) reported the fewest discontinuations based on safety concerns, although GA was associated with reports of higher burden and lower efficacy than other therapies. Difficulties with tolerability were more often reported as a reason for discontinuing subcutaneous (SC) IFNβ-1a than as a reason for discontinuing IM IFNβ-1a, GA, or SC IFNβ-1b. In the persistent therapy cohort, less patient-reported disability progression was reported with IM IFNβ-1a treatment than with SC IFNβ-1a, IFNβ-1b, or GA. These findings have relevance to clinical decision making and medication compliance in MS patient care.

Immunological mechanism of action and clinical profile of disease-modifying treatments in multiple sclerosis

Multiple sclerosis (MS) is a life-long, potentially debilitating disease of the central nervous system (CNS). MS is considered to be an immune-mediated disease, and the presence of autoreactive peripheral lymphocytes in CNS compartments is believed to be critical in the process of demyelination and tissue damage in MS. Although MS is not currently a curable disease, several disease-modifying therapies (DMTs) are now available, or are in development. These DMTs are all thought to primarily suppress autoimmune activity within the CNS. Each therapy has its own mechanism of action (MoA) and, as a consequence, each has a different efficacy and safety profile. Neurologists can now select therapies on a more individual, patient-tailored basis, with the aim of maximizing potential for long-term efficacy without interruptions in treatment. The MoA and clinical profile of MS therapies are important considerations when making that choice or when switching therapies due to suboptimal disease response. This article therefore reviews the known and putative immunological MoAs alongside a summary of the clinical profile of therapies approved for relapsing forms of MS, and those in late-stage development, based on published data from pivotal randomized, controlled trials.

Interferon alpha inhibits antigen-specific production of proinflammatory cytokines and enhances antigen-specific transforming growth factor beta production in antigen-induced arthritis

Introduction

Interferon alpha (IFN-α) has a complex role in autoimmunity, in that it may both enhance and prevent inflammation. We have previously shown that the presence of IFN-α at sensitization protects against subsequent antigen-triggered arthritis. To understand this tolerogenic mechanism, we performed a descriptive, hypothesis-generating study of cellular and humoral responses associated with IFN-α-mediated protection against arthritis.

Methods

Arthritis was evaluated at day 28 in mice given a subcutaneous injection of methylated bovine serum albumin (mBSA), together with Freund adjuvant and 0 to 5,000 U IFN-α at days 1 and 7, followed by intraarticular injection of mBSA alone at day 21. The effect of IFN-α on mBSA-specific IgG1, IgG2a, IgG2b, IgA, and IgE was evaluated by enzyme-linked immunosorbent assay (ELISA). Cytokines in circulation and in ex vivo cultures on mBSA restimulation was evaluated with ELISA and Luminex, and the identity of cytokine-producing cells by fluorescence-activated cell sorting (FACS) analysis.

Results

Administration of IFN-α protected mice from arthritis in a dose-dependent manner but had no effect on antigen-specific antibody levels. However, IFN-α did inhibit the initial increase of IL-6, IL-10, IL-12, and TNF, and the recall response induced by intraarticular mBSA challenge of IL-1β, IL-10, IL-12, TNF, IFN-γ, and IL-17 in serum. IFN-α decreased both macrophage and CD4⁺ T cell-derived IFN-γ production, whereas IL-17 was decreased only in CD4⁺ T cells. Ex vivo, in mBSA-restimulated spleen and lymph node cell cultures, the inhibitory effect of in vivo administration of IFN-α on proinflammatory cytokine production was clearly apparent, but had a time limit. An earlier macrophage-derived, and stronger activation of the antiinflammatory cytokine transforming growth factor beta (TGF-β) was observed in IFN-α-treated animals, combined with an increase in CD4⁺ T cells producing TGF-β when arthritis was triggered by mBSA (day 21). Presence of IFN-α at immunizations also prevented the reduction in TGF-β production, which was induced by the intraarticular mBSA injection triggering arthritis in control animals.

Conclusions

Administration of IFN-α has a profound effect on the cellular response to mBSA plus adjuvant, but does not affect antigen-specific Ig production. By including IFN-α at immunizations, spleen and lymph node cells inhibit their repertoire of antigen-induced proinflammatory cytokines while enhancing antiinflammatory TGF-β production, first in macrophages, and later also in CD4⁺ T cells. On intraarticular antigen challenge, this antiinflammatory state is reenforced, manifested as inhibition of proinflammatory recall responses and preservation of TGF-β levels. This may explain why IFN-α protects against antigen-induced arthritis.

The pharmacokinetics of glatiramer acetate for multiple sclerosis treatment

INTRODUCTION

Multiple sclerosis (MS) is a T-cell-mediated disease affecting the central nervous system (CNS), characterized by demyelination and axonal degeneration. INF-β1b was the first drug approved for MS patients in 1993. In 1996, glatiramer acetate (GA), a synthetic copolymer, was approved in the USA for the treatment of relapsing-remitting MS (RRMS) and clinically isolated syndrome (CIS). Although the immunological action of GA has been fully investigated, the exact mechanisms of action of GA are still not completely elucidated. Several in vitro studies on mice and human antigen-presenting cells (APCs) have shown that GA is able to bind to the major histocompatibility complex (MHC), on the surface of APCs, recognizing myelin basic protein (MBP).

AREAS COVERED

This review explores the pharmacological characteristics of GA, its mechanism of action and its pharmacokinetics properties. The article also provides information on the efficacy, tolerability and an overview of the most important clinical data on GA.

EXPERT OPINION

Despite the development of novel compounds, it is not surprising that GA is, to date, one of the most prescribed drugs for RRMS patients and CIS patients. The proven efficacy and the mild adverse events, makes GA a good therapeutic option in the early stage of the disease. This is particularly useful for patients who suffer flu-like symptoms from other RRMS therapies as an alternative.

[Interferon-β1b in multiple sclerosis therapy: more than 20 years clinical experience]

The introduction of interferon-β1b in 1993 in the USA and 2 years later in Europe made it possible for the first time to alter the course of the disease in patients with relapsing-remitting multiple sclerosis (MS). Subsequently, interferon-β1b was approved for the treatment of patients with active secondary progressive MS (1999) and early relapsing-remitting MS following a first demyelinating event (clinically isolated syndrome, CIS) (2006). Here we provide an overview of the clinical experience gathered during more than 20 years of interferon-β use focusing on long-term efficacy and safety and the impact of early initiation of treatment. Furthermore, the following aspects will be discussed: putative mechanisms of action of interferon-β, indications for a disease-modifying therapy, clinical relevance of neutralizing antibodies, importance of adherence in MS therapy, high versus low frequency therapy, combination therapies with interferon-β and safety of interferon-β in children and adolescents with MS and during pregnancy.

The effects of long-term interferon-beta-1b treatment on cognitive functioning in multiple sclerosis: a 16-year longitudinal study

BACKGROUND

Multiple sclerosis (MS) is a progressive disease of the central nervous system that affects cognition. Short-term treatment with interferon-beta-1b (IFN-b-1b) has been shown to have beneficial effects on cognition.

OBJECTIVE

The objective of this paper is to evaluate the effects of IFN-b-1b on cognitive functioning in patients with MS over the course of 16 years.

METHODS

Sixteen subjects with relapsing-remitting MS participated in the study. Nine of these subjects received IFN-b-1b, while seven received placebo treatment in the pivotal MS trial. After five years, all subjects were switched to IFN-b-1b treatment. At two and four years into the study, all subjects underwent a brief neuropsychological test battery, magnetic resonance imaging (MRI), and neurologic ratings; measures were repeated at 16 years.

RESULTS

Across the total cohort, cognitive functioning remained relatively stable over the course of 16 years. The placebo/IFN-b-b group exhibited increased visual memory performance relative to the IFN-b-1b treatment group, but had a greater decline in verbal memory. Initial MRI lesion load demonstrated a significant, negative correlation with overall cognitive performance at 16 years (p = 0.00).

CONCLUSION

We conclude that IFN-b-1b has beneficial effects on long-term cognition outcomes in MS.

Power failure: why small sample size undermines the reliability of neuroscience

A study with low statistical power has a reduced chance of detecting a true effect, but it is less well appreciated that low power also reduces the likelihood that a statistically significant result reflects a true effect. Here, we show that the average statistical power of studies in the neurosciences is very low. The consequences of this include overestimates of effect size and low reproducibility of results. There are also ethical dimensions to this problem, as unreliable research is inefficient and wasteful. Improving reproducibility in neuroscience is a key priority and requires attention to well-established but often ignored methodological principles.

Allelic combinations of immune-response genes as possible composite markers of IFN-β efficacy in multiple sclerosis patients

Background: IFN-β is widely used as the first-line disease-modifying treatment for multiple sclerosis. However, 30–50% of multiple sclerosis patients do not respond to this therapy. Identification of genetic variants and their combinations that predict responsiveness to IFN-β could be useful for treatment prognosis. Materials & methods: The combinations of alleles of nine polymorphic loci in immune-response genes were analyzed in 253 Russian multiple sclerosis patients as possible determinants of clinically optimal IFN-β treatment response using APSampler software. Results: Carriage of TGFB1*-509C and CCR5*d was associated with favorable IFN-β response by itself. CCR5*d, IFNAR1*16725G, IFNG*874T and IFNB1*153T/T were the components of the combinations, associated with clinically optimal response to IFN-β. Carriage of composite markers (CCR5*d + IFNAR1*G + IFNB1*T/T) or (CCR5*d + IFNAR1*G + IFNG*T) is beneficial for IFN-β treatment efficacy. Discussion: The data obtained provides evidence of the cumulative effect of immune-response genes on IFN-β treatment efficacy. This joint contribution may reflect the additive effect of independent allelic variants and epistatic interactions between some of them.

Original submitted 2 July 2012; Revision submitted 21 September 2012

Annualized relapse rate of first-line treatments for multiple sclerosis: a meta-analysis, including indirect comparisons versus fingolimod

OBJECTIVES

Previous systematic reviews and meta-analyses of treatments in relapsing-remitting multiple sclerosis (RRMS) derived their findings from either placebo-controlled studies only or separately from head-to-head and comparative studies. The purpose of this study is to compare annualized relapse rates (ARR) of fingolimod versus all of the commonly used first-line treatments in RRMS using evidence from both placebo-controlled and head-to-head studies. In absence of the head-to-head data between fingolimod and the other treatments, these comparisons were formed using meta-analysis techniques for indirect treatment comparisons.

METHODS

A systematic literature review was conducted by searching MEDLINE, EMBASE, and the Cochrane Library with no limitations applied on publication language or dates. Included studies were randomized controlled trials evaluating one or more of fingolimod, interferon beta-1a, interferon beta-1b, or glatiramer acetate in RRMS populations. Primary outcome was ARR. Data extraction included author, year, treatment, dosage, mean age, percentage females, duration of disease, Expanded Disability Status Scale (EDSS) score at baseline, relapses in 2 years prior to baseline, trial duration, relapse-related outcome, and definition of relapse. The indirect treatment comparisons were performed using a mixed-treatment comparison framework. ARR was analyzed as a Poisson outcome.

RESULTS

The relative ARRs, for each treatment versus fingolimod, estimated from our meta-analyses were 1.43 (glatiramer acetate 20 mg), 1.51 (interferon beta-1b 250 mcg), 1.55 (interferon beta-1a 44 mcg), 1.67 (interferon beta-1a 22 mcg), 1.93 (interferon beta-1a 30 mcg), and 2.32 (placebo). None of the 95% confidence intervals for these estimates overlapped unity, implying statistical significance of these findings.

LIMITATIONS

The key limitations of this study are the persisting heterogeneity even after adjusting for covariates and the variability in outcome definition across the included trials.

CONCLUSIONS

Our study demonstrated that fingolimod significantly reduces relapse frequency in patients with RRMS compared with current first-line disease-modifying therapies.

Interferon beta for secondary progressive multiple sclerosis

BACKGROUND

Therapy with either recombinant beta-1a or beta-1b interferons (IFNs) is worldwide approved for Relapsing Remitting Multiple Sclerosis (RRMS). A major unanswered question is whether this treatment is able to safely reverse or retard the progressive phase of the disease.

OBJECTIVES

The main objective was to verify whether IFNs treatment in Secondary Progressive Multiple Sclerosis (SPMS) is more effective than placebo in reducing the number of patients who experience disability progression.

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis Group's Trials Register (1995 to 15 February 2011), the reference lists of relevant articles and conference proceedings. Regulatory agencies were used as additional sources of information.

SELECTION CRITERIA

We included all randomised, double or single blind, placebo-controlled trials (RCTs) evaluating the efficacy of IFNs versus placebo in SPMS patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all reports retrieved from the search. They independently extracted clinical, safety and MRI data, using a predefined data extraction form, resolving disagreements after discussion with a third reviewer. Risk of bias was evaluated to assess the quality of the studies. Treatment effect was measured using Risk Ratio (RR) with 95% confidence intervals (CI) for the binary outcomes and Standard Mean Difference with 95% CI for the continuous outcomes.

MAIN RESULTS

Five RCTs met the inclusion criteria, from which 3122 (1829 IFN and 1293 placebo) treated patients contributed to the analysis. Included population was heterogeneous in terms of baseline clinical characteristics of the disease, in particular the percentage of patients affected by secondary progression with superimposed relapse ranging from 72% to 44%. IFN beta 1a and 1b did not decrease the risk of progression sustained at 6 months (RR, 95% CI: 0.98, [0.82-1.16]) after three years of treatment. A significant decrease of the risk of progression sustained at 3 months (RR, 95% CI: 0.88 [0.80, 0.97]) and of the risk of developing new relapses at three years (RR 0.91, [0.84-0.97]) were found. The risk of developing new active brain lesions decreased over time but this data was obtained from single studies on Magnetic Resonance Imaging (MRI), performed in subgroups of patients; in spite of no effect on progression, the radiological data supported an effect on MRI parameters. The safety profile reflects what is commonly reported in MS IFN-treated patients.

AUTHORS' CONCLUSIONS

Well designed RCTs, evaluating a high number of patients were included in the review. Recombinant IFN beta does not prevent the development of permanent physical disability in SPMS. We were unable to verify the effect on cognitive function for the lack of comparable data. This treatment significantly reduces the risk of relapse and of short -term relapse-related disability.Overall, these results show that IFNs' anti-inflammatory effect is unable to retard progression, when established. In the future, no new RCTs for IFNs versus placebo in SPMS will probably be undertaken, because research is now focusing on innovative drugs. We believe that this review gives conclusive evidence on the clinical efficacy of IFNs versus placebo in SPMS.

Quantitative differences in the immunomodulatory effects of Rebif and Avonex in IFN-β 1a treated multiple sclerosis patients

Interferon-β (IFN-β) is a current effective treatment for multiple sclerosis (MS) and exerts its therapeutic effects by down-modulating the systemic immune response and cytokine signaling. In clinical practice there are several formulations of interferon including a low dose of IFN-β 1a formulation of 30 μg IM once weekly (Avonex) and a high dose formulation of 44 μg SC three times weekly (Rebif). Recent studies suggest that Rebif is more efficacious compared to Avonex in preventing relapses and decreasing MRI activity in relapsing remitting MS (RRMS) patients. This study examines whether there are quantitative gene expression changes in interferon-treated RRMS patients that can explain the difference in efficacy and side effects between Rebif and Avonex. Herein, RRMS patients were treated for three months with IFN-β 1a and the levels of plasma cytokines and gene expression in peripheral blood mononuclear cells were examined. Thirty-two normal subjects were compared to thirty-two RRMS patients, of which ten were treated with Rebif and ten with Avonex. Rebif and Avonex both significantly and equally suppressed plasma TNF-α and IL-6 levels. Rebif suppressed IL-13 significantly more than Avonex. Rebif also significantly suppressed the levels of the chemokines CCL17 and RANTES, the protease ADAM8, and COX-2 at a higher degree compared to Avonex. The STAT1-inducible genes IP-10 and caspase 1 were significantly increased with Rebif compared to Avonex. In conclusion, the higher dosed, more frequently administered IFN-β 1a Rebif when compared to IFN-β 1a Avonex has more potent immunomodulatory effects. These quantitative results might relate to efficacy and side-effect profile of the two IFN-β 1a formulations and provide prospective practical clinical tools to monitor treatment and adjust dosage.