Immunosuppressive therapy is more effective than interferon in neuromyelitis optica

To determine long-term treatment (LTT) of neuromyelitis optica (NMO), we retrospectively reviewed therapies of 26 patients with NMO followed in five French neurological departments. To assess LTT efficacy, the probability of relapse free after LTT was analysed. Patients were divided into two groups according to the first treatment receiving interferon beta (IFN Group, seven patients) or immunosuppressants (IS Group, 19 patients). The probability of relapse was significantly lower in the IS Group (P = 0.0007). From our results, interferon beta is not recommended, and one of the best current therapeutic options for NMO appears to be immunosuppressants. Multiple Sclerosis 2007; 13: 256–259. http://msj.sagepub.com

Interferon beta preparations for the treatment of multiple sclerosis patients differ in neutralizing antibody seroprevalence and immunogenicity

Development of neutralizing antibodies (NAbs) reduces the clinical efficacy of interferon beta (IFNβ) treatment in multiple sclerosis (MS) patients. The aim of this study was to evaluate NAb seroprevalence (frequency of patients with NAbs) and immunogenicity (titer levels) of IFNβ preparations in a clinical setting. We analysed 1115 consecutive MS patients, treated with one of the three available IFNβ preparations, for an average of 40 months (1 – 120 months), for the presence of NAbs with the MxA protein induction assay. Overall, 32% of patients were positive for NAbs with neutralizing titers above 10. The frequency of NAbs, ie, the seroprevalence, was 13% in Avonex-treated patients, 43% for Betaferon, 39% for Rebif22 and 30% for Rebif44. In addition, the potential to induce high titer levels, ie, the immunogenicity, was observed to differ between preparations. Avonex, showing the lowest seroprevalence, also showed low immunogenicity and typically induced low titers. Betaferon, showing the highest seroprevalence when inducing NAbs, induced lower titers compared to Rebif22 and Rebif44. Treatment duration over five years only marginally correlated with decreased seroprevalence and titer levels.

In conclusion, NAbs to IFNβ are common in a clinical setting and the IFNβ preparations differ not only in NAb seroprevalence, but also in immunogenicity. Multiple Sclerosis 2007; 13: 208–214. http://msj.sagepub.com

Normal-appearing grey and white matter T1 abnormality in early relapsing–remitting multiple sclerosis: a longitudinal study

Objective

To investigate the presence and evolution of T1 relaxation time abnormalities in normal-appearing white matter (NAWM) and grey matter (GM), early in the course of relapsing–remitting multiple sclerosis (MS).

Methods

Twenty-three patients with early relapsing–remitting MS and 14 healthy controls were imaged six monthly for up to three years. Mean follow-up was 26 months for MS patients and 24 months for controls. Dual-echo fast-spin echo and gradient-echo proton-density and T1-weighted data sets (permitting the calculation of a T1 map) were acquired in all subjects. GM and NAWM T1 histograms were produced and a hierarchical regression model was used to investigate changes in T1 over time.

Results

At baseline, significant patient-control differences were seen, both in NAWM (P = 0.001) and in GM (P = 0.01). At follow-up, there was no evidence for a serial change in either mean T1 or peak-location for either NAWM or GM. There was weak evidence for a decline in patient NAWM peak-height and also evidence for a decline in control GM peak-height.

Conclusion

There are significant and persistent abnormalities of NAWM and GM T1 in early relapsing-remitting MS. Further studies should address whether such T1 measures have a role in prognosis or therapeutic monitoring. Multiple Sclerosis 2007; 13:169–177. http://msj.sagepub.com

Ocrelizumab versus Interferon Beta-1a in Relapsing Multiple Sclerosis

BACKGROUND

B cells influence the pathogenesis of multiple sclerosis. Ocrelizumab is a humanized monoclonal antibody that selectively depletes CD20+ B cells.

METHODS

In two identical phase 3 trials, we randomly assigned 821 and 835 patients with relapsing multiple sclerosis to receive intravenous ocrelizumab at a dose of 600 mg every 24 weeks or subcutaneous interferon beta-1a at a dose of 44 μg three times weekly for 96 weeks. The primary end point was the annualized relapse rate.

RESULTS

The annualized relapse rate was lower with ocrelizumab than with interferon beta-1a in trial 1 (0.16 vs. 0.29; 46% lower rate with ocrelizumab; P<0.001) and in trial 2 (0.16 vs. 0.29; 47% lower rate; P<0.001). In prespecified pooled analyses, the percentage of patients with disability progression confirmed at 12 weeks was significantly lower with ocrelizumab than with interferon beta-1a (9.1% vs. 13.6%; hazard ratio, 0.60; 95% confidence interval [CI], 0.45 to 0.81; P<0.001), as was the percentage of patients with disability progression confirmed at 24 weeks (6.9% vs. 10.5%; hazard ratio, 0.60; 95% CI, 0.43 to 0.84; P=0.003). The mean number of gadolinium-enhancing lesions per T₁-weighted magnetic resonance scan was 0.02 with ocrelizumab versus 0.29 with interferon beta-1a in trial 1 (94% lower number of lesions with ocrelizumab, P<0.001) and 0.02 versus 0.42 in trial 2 (95% lower number of lesions, P<0.001). The change in the Multiple Sclerosis Functional Composite score (a composite measure of walking speed, upper-limb movements, and cognition; for this z score, negative values indicate worsening and positive values indicate improvement) significantly favored ocrelizumab over interferon beta-1a in trial 2 (0.28 vs. 0.17, P=0.004) but not in trial 1 (0.21 vs. 0.17, P=0.33). Infusion-related reactions occurred in 34.3% of the patients treated with ocrelizumab. Serious infection occurred in 1.3% of the patients treated with ocrelizumab and in 2.9% of those treated with interferon beta-1a. Neoplasms occurred in 0.5% of the patients treated with ocrelizumab and in 0.2% of those treated with interferon beta-1a.

CONCLUSIONS

Among patients with relapsing multiple sclerosis, ocrelizumab was associated with lower rates of disease activity and progression than interferon beta-1a over a period of 96 weeks. Larger and longer studies of the safety of ocrelizumab are required. (Funded by F. Hoffmann-La Roche; OPERA I and II ClinicalTrials.gov numbers, NCT01247324 and NCT01412333 , respectively.).

[Necrotic toes in a female patient using interferon]

BACKGROUND

Interferon has an important role in treatment of viral hepatitis, multiple sclerosis and solid and non-solid tumours. Ischaemia and necrosis of the extremities are relatively little-known adverse effects of treatment with interferon.

CASE DESCRIPTION

A 44-year-old woman was treated with interferon-beta for relapsing-remitting multiple sclerosis. She developed ischaemia and necrosis of the right lower extremity. Extensive laboratory and imaging investigations offered no clear diagnosis, leading to suspicion of a connexion with interferon-beta treatment. Discontinuation of interferon lead to rapid healing, clearly suggesting a relationship between interferon and the vascular complications.

CONCLUSION

Vascular complications during treatment with interferon seem to arise fairly frequently, and can even occur many years after commencing therapy. When vascular symptoms similar to Raynaud's syndrome develop, careful monitoring of the disease course and treatment with vasodilators if required is important. If this is insufficiently effective, interferon should be discontinued. Prompt recognition can prevent significant morbidity in these patients.

Pharmacogenetic study of long-term response to interferon-β treatment in multiple sclerosis

The aim of the study is the identification of genetic factors that influence the long-term response to interferon-β (IFNβ) (4-year follow-up). We performed a genome-wide association study in 337 IFNβ-treated Italian multiple sclerosis patients at the extreme of treatment response, and we meta-analyzed association effects, integrating results with pathway analysis, gene-expression profiling of IFNβ-stimulated peripheral blood mononuclear cells from 20 healthy controls (HC) and expression quantitative locus (eQTL) analyses. From meta-analysis, 43 markers were associated at P<10-4, and two of them (rs7298096 and rs4726460) pointed to two genes, NINJ2 and TBXAS1, that were significantly downregulated after IFNβ stimulation in HC (P=3.1 × 10-9 and 5.6 × 10-10). We also observed an eQTL effect for the allele associated with favorable treatment response (rs4726460A); moreover, TBXAS1 appeared downregulated upon IFNβ administration (β=-0.39; P=0.02). Finally, we found an enrichment of pathways related to inflammatory processes and presynaptic membrane, the latter with involvement of genes related to glutamatergic system (GRM3 and GRIK2), confirming its potential role in the response to IFNβ.

Multiple sclerosis: Association of gelatinase B/matrix metalloproteinase-9 with risk and clinical course the disease

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease characterized by inflammation and axonal degeneration of the central nervous system and a leading cause of disability in young adults. The matrix metalloproteinases in general and specially gelatinase B/metalloproteinase-9 (MMP-9) plays a role in the pathogenesis of multiple sclerosis.

OBJECTIVE

To investigate the presence of the MMP-9 -1562C/T polymorphism in a Portuguese population of MS patients and assess its impact in susceptibility and course of the disease. The relation of MMP-9 serum levels with the polymorphism and with clinical and therapeutic factors will also be assessed.

METHODS

Our study included 355 Caucasian individuals distributed as MS patients (n=169) and controls (n=186). Samples were genotyped for -1562C/T polymorphism by PCR-RFLP analysis. MMP-9 concentration in serum was analyzed using a commercially available enzyme-linked immunosorbent assay.

RESULTS

A significant increase in T-allele frequency was found in female MS patients, but not in the total patient population. No association between the presence of the polymorphism and disease progression was found. MMP-9 serum concentrations were increased in patients, and although not influenced by the -1562C/T polymorphism, were modified by INF-beta therapy.

CONCLUSION

Although we did not find an association of this polymorphism with disease susceptibility or prognosis, MMP-9 appears to be a good therapeutic response marker for multiple sclerosis.

Pharmacological treatment other than corticosteroids, intravenous immunoglobulin and plasma exchange for Guillain-Barré syndrome

BACKGROUND

Plasma exchange and intravenous immunoglobulin, but not corticosteroids, are beneficial in Guillain-Barré syndrome (GBS). The efficacy of other pharmacological agents is unknown. This review was first published in 2011 and updated in 2013 and 2016.

OBJECTIVES

To assess the effects of pharmacological agents other than plasma exchange, intravenous immunoglobulin and corticosteroids for GBS.

SEARCH METHODS

On 18 January 2016, we searched the Cochrane Neuromuscular Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE, and Embase for treatments for GBS. We also searched clinical trials registries.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) or quasi-RCTs of acute GBS (within four weeks from onset) of all types and degrees of severity, and in individuals of all ages. We discarded trials that investigated only corticosteroids, intravenous immunoglobulin or plasma exchange. We included other pharmacological treatments or combinations of treatments compared with no treatment, placebo or another treatment. We also identified a number of non-randomised studies during the search, the results of which we considered in the Discussion.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology.

MAIN RESULTS

We identified no new trials during this update of the review. In previous versions of this review we identified only very low quality evidence for four different interventions published in four studies. Each study had a high risk of bias in at least one respect. One RCT with 19 participants comparing interferon beta-1a and placebo showed no clinically important difference in any outcome between groups. Another with 10 participants comparing brain-derived neurotrophic factor and placebo showed no clinically important difference in any outcome between groups. A third with 37 participants comparing cerebrospinal fluid filtration and plasma exchange also showed no clinically important difference in any outcome between groups. In a fourth with 43 participants, the risk ratio for an improvement by one or more disability grade after eight weeks was greater with the Chinese herbal medicine tripterygium polyglycoside than with corticosteroids (risk ratio 1.47; 95% confidence interval 1.02 to 2.11); other outcomes in this trial showed no difference. Serious adverse events were uncommon with each of these treatments and in the control groups.

AUTHORS' CONCLUSIONS

The quality of the evidence was very low. Three small RCTs, comparing interferon beta-1a or brain-derived neurotrophic factor with placebo, and cerebrospinal fluid filtration with plasma exchange, showed no significant benefit or harm for any of the interventions. A fourth small trial showed that the Chinese herbal medicine, tripterygium polyglycoside, hastened recovery in people with GBS to a greater extent than corticosteroids, but this result needs confirmation. We were unable to draw any useful conclusions from the few observational studies we identified.

Occurrence of Anti-Drug Antibodies against Interferon-Beta and Natalizumab in Multiple Sclerosis: A Collaborative Cohort Analysis

Immunogenicity of biopharmaceutical products in multiple sclerosis is a frequent side effect which has a multifactorial etiology. Here we study associations between anti-drug antibody (ADA) occurrence and demographic and clinical factors. Retrospective data from routine ADA test laboratories in Sweden, Denmark, Austria and Germany (Dusseldorf group) and from one research study in Germany (Munich group) were gathered to build a collaborative multi-cohort dataset within the framework of the ABIRISK project. A subset of 5638 interferon-beta (IFNβ)-treated and 3440 natalizumab-treated patients having data on at least the first two years of treatment were eligible for interval-censored time-to-event analysis. In multivariate Cox regression, IFNβ-1a subcutaneous and IFNβ-1b subcutaneous treated patients were at higher risk of ADA occurrence compared to IFNβ-1a intramuscular-treated patients (pooled HR = 6.4, 95% CI 4.9-8.4 and pooled HR = 8.7, 95% CI 6.6-11.4 respectively). Patients older than 50 years at start of IFNβ therapy developed ADA more frequently than adult patients younger than 30 (pooled HR = 1.8, 95% CI 1.4-2.3). Men developed ADA more frequently than women (pooled HR = 1.3, 95% CI 1.1-1.6). Interestingly we observed that in Sweden and Germany, patients who started IFNβ in April were at higher risk of developing ADA (HR = 1.6, 95% CI 1.1-2.4 and HR = 2.4, 95% CI 1.5-3.9 respectively). This result is not confirmed in the other cohorts and warrants further investigations. Concerning natalizumab, patients older than 45 years had a higher ADA rate (pooled HR = 1.4, 95% CI 1.0-1.8) and women developed ADA more frequently than men (pooled HR = 1.4, 95% CI 1.0-2.0). We confirmed previously reported differences in immunogenicity of the different types of IFNβ. Differences in ADA occurrence by sex and age are reported here for the first time. These findings should be further investigated taking into account other exposures and biomarkers.

The cross-reactivity of binding antibodies with different interferon beta formulations used as disease-modifying drugs in multiple sclerosis patients

Interferon beta (IFNb) preparations are commonly used as first-line therapy in relapsing-remitting multiple sclerosis (RRMS). They are, however, characterized by limited efficacy, partly due to the formation of anti-IFNb antibodies in patients.In this pilot study, we assessed with the ELISA method the presence of the binding antibodies (BAbs) against interferon beta after 2 years of therapy with subcutaneous interferon beta 1a (Rebif) in 49 RRMS patients. Antibody levels were established again within 1 year after treatment withdrawal. We used 3 interferons that are commercially available for MS therapy, namely Avonex (Biogen Idec Limited), Rebif (Merck Serono), and Betaferon (Bayer Pharma AG), as antigens.BAbs reacting with Rebif were found in 24.4% to 55% of patients, depending on the units of their expression. The levels of anti-Rebif antibodies remained high in 8 patients and in 4 patients they dropped significantly. Strong correlations were obtained in all assays (anti-Rebif-anti-Avonex, anti-Rebif-anti-Betaferon, and anti-Betaferon-anti-Avonex) and the existence of cross-reactivity in the formation of antibodies against all the tested formulations of interferon beta was confirmed. The levels of BAbs remain significant in the clinical context, and their assessment is the first choice screening; however, methods of BAbs evaluation can be crucial for further decisions. More studies are needed to confirm our results; specifically it would be of interest to evaluate methods of neutralizing antibodies identification, as we only assessed the binding antibodies. Nevertheless, our results support the concept that in interferon nonresponders, that are positive for binding antibodies, switching the therapy to alternative disease-modifying agent (for example glatiramer acetate, fingolimod, or natalizumab) is justified, whereas the switch to another interferon formulation will probably be of no benefit.

miR-145 and miR20a-5p Potentially Mediate Pleiotropic Effects of Interferon-Beta Through Mitogen-Activated Protein Kinase Signaling Pathway in Multiple Sclerosis Patients

MicroRNAs (miRNAs) are crucial to the immunopathogenesis of multiple sclerosis (MS). The mechanism of action of interferon beta (IFN-β) in relapsing-remitting (RR) MS patients is largely unknown. miR-145 and miR-20a-5p previously reported as diagnosis biomarker in treatment naïve RRMS patients and their expression after IFN-β therapy might be indicative of molecular mechanism of IFN-β. Cross-talking between JAK/STAT pathway and complementary pathways like MAPK is important in IFN-β signaling. Here, in order to clarify the ambiguous molecular mechanism of IFN-β and evaluate the potential use of them as a biomarker for monitoring of therapy, we investigated the expression of miR-145 and miR-20a-5p in blood sample of 15 treatment naïve RRMS patients, 15 IFN-β-treated RRMS patients, and 15 healthy volunteers (HVs). In silico molecular signaling pathway enrichment analysis was fulfilled on validated and predicted targets of miR-145 and miR-20a-5p to probe the plausible role of them on molecular effects of IFN-β. We identified miR-145 and miR-20a-5p level was normalized in IFN-β-treated patients, and MAPK pathway was one of the most relevant pathways that recognized by molecular signaling pathway enrichment analysis. Moreover, ROC curve analysis of miR-145 indicated that this miRNA could be used for monitoring of response to IFN-β therapy. Restoration of miR-145 and miR-20a expression in IFN-β-treated patients suggests that pleiotropic effects of IFN-β might be through miRNAs. Enrichment of MAPK pathway underscores the importance of non-canonical pathways in IFN-β signaling.

IFN-β Facilitates Neuroantigen-Dependent Induction of CD25+ FOXP3+ Regulatory T Cells That Suppress Experimental Autoimmune Encephalomyelitis

This study introduces a flexible format for tolerogenic vaccination that incorporates IFN-β and neuroantigen (NAg) in the Alum adjuvant. Tolerogenic vaccination required all three components, IFN-β, NAg, and Alum, for inhibition of experimental autoimmune encephalomyelitis (EAE) and induction of tolerance. Vaccination with IFN-β + NAg in Alum ameliorated NAg-specific sensitization and inhibited EAE in C57BL/6 mice in pretreatment and therapeutic regimens. Tolerance induction was specific for the tolerogenic vaccine Ag PLP178-191 or myelin oligodendrocyte glycoprotein (MOG)35-55 in proteolipid protein- and MOG-induced models of EAE, respectively, and was abrogated by pretreatment with a depleting anti-CD25 mAb. IFN-β/Alum-based vaccination exhibited hallmarks of infectious tolerance, because IFN-β + OVA in Alum-specific vaccination inhibited EAE elicited by OVA + MOG in CFA but not EAE elicited by MOG in CFA. IFN-β + NAg in Alum vaccination elicited elevated numbers and percentages of FOXP3+ T cells in blood and secondary lymphoid organs in 2D2 MOG-specific transgenic mice, and repeated boosters facilitated generation of activated CD44high CD25+ regulatory T cell (Treg) populations. IFN-β and MOG35-55 elicited suppressive FOXP3+ Tregs in vitro in the absence of Alum via a mechanism that was neutralized by anti-TGF-β and that resulted in the induction of an effector CD69+ CTLA-4+ IFNAR+ FOXP3+ Treg subset. In vitro IFN-β + MOG-induced Tregs inhibited EAE when transferred into actively challenged recipients. Unlike IFN-β + NAg in Alum vaccines, vaccination with TGF-β + MOG35-55 in Alum did not increase Treg percentages in vivo. Overall, this study indicates that IFN-β + NAg in Alum vaccination elicits NAg-specific, suppressive CD25+ Tregs that inhibit CNS autoimmune disease. Thus, IFN-β has the activity spectrum that drives selective responses of suppressive FOXP3+ Tregs.

[The methods of detection of binding and neutralizing antibodies to preparations of interferon-beta]

The human recombinant β-interferon is most frequently applied for treatment of remittent recurrent form of multiple sclerosis using pharmaceuticals. The clinical response to applied therapy is absent in some of patients that can be conditioned by development of antibodies too preparations. Depending on possibility of blocking binding of human recombinant β-interferon with its receptor, all antibodies are divided on binding and neutralizing ones. The purpose of study is to investigate analytical and clinical diagnostic parameters of tests using for detection of different types of antibodies synthesized against human recombinant β-interferon. The study sampling consisted of 33 patients with remittent recurrent form of multiple sclerosis receiving therapy with human recombinant β-interferon and also of 40 donors and 15 patients with multiple sclerosis without therapy with human recombinant β-interferon. The concentration of binding antibodies was measured by enzyme-linked immunosorbent assay. Also immune blotting assay was applied. The titer of neutralizing antibodies was determined using cell line HL-116 sensitive to human recombinant β-interferon. The binding and neutralizing antibodies were not detected in donors and patients without human recombinant β-interferon therapy. The prevalence of binding antibodies to human recombinant β-interferon amounted to 57.6% when analysis of samples using immune blotting assay was used and 60.6% when commercial testing system was applied. The statistical analysis of results demonstrated high convergence and correlation of values of concentrations of binding antibodies obtained using immune blotting assay and enzyme-linked immunosorbent assay (r=0.9159, p<0.0001). The clinically significant titers of neutralizing antibodies were detected in 21.21°% of patients. All patients with clinically significant titer of neutralizing antibodies were positive in relation to binding antibodies measured by immune blotting assay and enzyme-linked immunosorbent assay. The high correlation between values of titers of neutralizing antibodies and concentration of binding antibodies measured by immune blotting assay (r=0.7909, p=0.0055). The application in clinical practice of data concerning presence of binding and neutralizing antibodies to human recombinant β-interferon can input into optimization of therapy with expensive biologic preparations in patients with multiple sclerosis and other autoimmune diseases.

Monitoring interferon β treatment response with magnetic resonance spectroscopy in relapsing remitting multiple sclerosis

The aim of this study is to compare the white matter of multiple sclerosis (MS) patients with healthy controls and to monitor the response to the treatment with magnetic resonance spectroscopy (MRS).Fifteen healthy controls and 36 recently diagnosed MS patients never treated with interferon β were included in this study. In the patient group, MRS was performed before treatment, at 6th and 12th month after the initiation of treatment and once in control group. Patient group was divided into 3 interferon groups randomly. Physical examination findings were recorded as Expanded Disability Status Scale scores before treatment, at 6th and 12th month of interferon treatment.At the end of 1 year follow up, 26 of 36 patients completed the study. In patients' white matter lesions, N-acetylaspartate/creatine (NAA/Cr) ratios were lower than control group's white matters. NAA/Cr ratios were higher in control group's white matter than patient's normal appearing white matter but this difference was not statistically significant. There was no difference in choline/creatine (Cho/Cr) ratios between 2 groups. In follow-up period, NAA/Cr and Cho/Cr ratios obtained from patients' white matter lesions and normal appearing white matter did not change statistically.This study showed that in MS patients' white matters, especially in white matter lesions, neuron viability is reduced compared with healthy controls' normal white matter; and in the patients treated with interferon β NAA/Cr ratios remained stable. These stable levels of metabolite ratios in the patients who received interferon β therapy can be explained with either the shortness of the follow-up period post-treatment or may reflect a positive effect of the beta interferon therapy on the progress of MS.

Disease modifying therapies for relapsing multiple sclerosis

Multiple sclerosis (MS) is a common, disabling, putatively autoimmune neurological disease with worldwide distribution. It typically begins as a relapsing disorder that later evolves to a secondary progressive phase. Inflammatory and neurodegenerative mechanisms seem to operate in both phases, but their relative contributions and interactions are incompletely understood. Disease modifying therapies (DMTs) approved for relapsing multiple sclerosis interfere with a variety of immunological mechanisms to reduce rates of relapse, accumulation of disease burden measured by magnetic resonance imaging (MRI), and decline in neurological function over the two to three year duration of typical randomized controlled trials. Benefits of longer duration of therapy on disability are less clear, as data beyond three years are largely limited to observational studies. However, current DMTs do not slow accrual of disability once progressive multiple sclerosis is established. This review summarizes the evidence about the use of approved DMTs and examines how to individualize treatment despite the absence of validated biomarkers to guide drug selection. Methods such as stratifying patients on the basis of estimated risk for future disability, weighing patient specific factors and preferences, and using objective outcomes to adjudicate treatment success are discussed. Emerging drug therapies and strategies are also reviewed.

[Response to treatment with interferon beta in patients with multiple sclerosis. Validation of the Rio Score]

INTRODUCTION

Different criteria have been proposed for the response to treatment with interferon beta, and the Rio Score is one of the most widely used. The aim of this study was to validate the usefulness of the Rio Score in an independent cohort.

PATIENTS AND METHODS

A multi-centre, prospective, longitudinal study was conducted on patients with relapsing-remitting multiple sclerosis treated with interferon beta. The patients were classified according to the presence of attacks, active lesions (new in T2 or gadolinium enhancing lesions) in magnetic resonance imaging, a confirmed increase in disability or combinations of these variables (attacks, increase on the Expanded Disability Status Scale and active lesions) after one year's treatment. Regression analysis was used in order to identify the response-predicting variables after a three-year follow-up.

RESULTS

The sample consisted of 249 patients with relapsing-remitting multiple sclerosis. The logistic model confirmed that the presence of two (odds ratio = 6.6; CI 95% = 2.7-16.1; p < 0.0001) or three (odds ratio = 8.5; CI 95% = 1.6-46; p < 0.01) positive variables during the first year of treatment were indicative of a significant risk of activity (attacks or progression) in the next two years.

CONCLUSIONS

The usefulness of the Rio Score is confirmed, in an independent cohort, as a means of identifying patients with a higher risk of developing clinical activity or progression of disability during treatment with interferon beta.

Comparison of Statistical Approaches for Dealing With Immortal Time Bias in Drug Effectiveness Studies

In time-to-event analyses of observational studies of drug effectiveness, incorrect handling of the period between cohort entry and first treatment exposure during follow-up may result in immortal time bias. This bias can be eliminated by acknowledging a change in treatment exposure status with time-dependent analyses, such as fitting a time-dependent Cox model. The prescription time-distribution matching (PTDM) method has been proposed as a simpler approach for controlling immortal time bias. Using simulation studies and theoretical quantification of bias, we compared the performance of the PTDM approach with that of the time-dependent Cox model in the presence of immortal time. Both assessments revealed that the PTDM approach did not adequately address immortal time bias. Based on our simulation results, another recently proposed observational data analysis technique, the sequential Cox approach, was found to be more useful than the PTDM approach (Cox: bias = -0.002, mean squared error = 0.025; PTDM: bias = -1.411, mean squared error = 2.011). We applied these approaches to investigate the association of β-interferon treatment with delaying disability progression in a multiple sclerosis cohort in British Columbia, Canada (Long-Term Benefits and Adverse Effects of Beta-Interferon for Multiple Sclerosis (BeAMS) Study, 1995-2008).

Long-Term Adherence to IFN Beta-1a Treatment when Using RebiSmart® Device in Patients with Relapsing-Remitting Multiple Sclerosis

The effectiveness of disease-modifying drugs in the treatment of multiple sclerosis is associated with adherence. RebiSmart® electronic device provides useful information about adherence to the treatment with subcutaneous (sc) interferon (IFN) β-1a (Rebif®). The aim of the study was to determine long-term adherence to this treatment in patients with relapsing-remitting multiple sclerosis (RRMS). This retrospective multicentre observational study analysed 258 patients with RRMS who were receiving sc IFN β-1a (Rebif®) treatment by using RebiSmart® until replacement (36 months maximum lifetime) or treatment discontinuation. Adherence was calculated with data (injection dosage, time, and date) automatically recorded by RebiSmart®. Patients in the study had a mean age of 41 years with a female proportion of 68%. Mean EDSS score at start of treatment was 1.8 (95% CI, 1.6-1.9). Overall adherence was 92.6% (95% CI, 90.6-94.5%). A total of 30.2% of patients achieved an adherence rate of 100%, 80.6% at least 90%, and only 13.2% of patients showed a suboptimal adherence (<80%). A total of 59.9% of subjects were relapse-free after treatment initiation. Among 106 subjects (41.1%) who experienced, on average, 1.4 relapses, the majority were mild (40.6%) or moderate (47.2%). Having experienced relapses from the beginning of the treatment was the only variable significantly related to achieving an adherence of at least 80% (OR = 3.06, 1.28-7.31). Results of this study indicate that sc IFN β-1a administration facilitated by RebiSmart® could lead to high rates of adherence to a prescribed dose regimen over 36 months.

The Cost of Relapsing-Remitting Multiple Sclerosis Patients Who Develop Neutralizing Antibodies during Interferon Beta Therapy

BACKGROUND

Relapsing Remitting Multiple Sclerosis (RRMS) patients treated with interferon beta (IFN beta) can develop neutralizing antibodies (NAbs) that reduce treatment efficacy. Several clinical studies explored the association of NAb+ status with increased disease activity.

OBJECTIVE

The aim of this study was to estimate the cost of RRMS patients who develop NAbs while treated with IFN beta by the Italian National Healthcare Service (NHS) and the Italian Society perspectives.

METHODS

The clinical data derived from a published observational study on 567 RRMS Italian patients treated with IFN beta. The management cost data derived from the published literature. Cost data were inflated to Euro 2014.

RESULTS

The annual direct cost to treat a patient was estimated in €15,428 in the NAb+ cohort and €14,317 in the NAb- cohort. The annual societal cost was estimated in €33,890 and €30,790 in NAb+ and NAb- patients, respectively. The cost increase related to the NAb+ status was €3,100 in the Italian societal perspective and €1,111 in the Italian NHS perspective.

CONCLUSION

The results of this economic evaluation suggest the presence of an association between NAb+ status and increased costs for the management of RRMS in Italy. Further pharmacoeconomic research will be needed to confirm this first result.

Longitudinal analyses of the effects of neutralizing antibodies on interferon beta-1b in relapsing-remitting multiple sclerosis

We have analysed data on exacerbation rates, Expanded Disability Status Scale (EDSS) scores, and lesion burdens using the results of two neutralizing antibody (NA B) assays (C PE and MxA) from the pivotal relapsing-remitting multiple sclerosis (MS) trial of interferon beta-1b (IFNB) with a longitudinal appro ach, where the influence of NA Bs in individual patients is assessed by comparing responses during NAB- positive and NA B-negative periods. There are apparent influences on exacerbation rate related to dose of IFNB, titer level, and duration of positivity. With the MxA assay, exacerbation rates after switching to NA B-positive status are estimated to be 28% higher [95% confidence interval (CI): (-15%, 92%)] and -2% higher [95% CI: (-21%, 21%)] on the low- and high-dose IFNB arms, respectively. When compared with all NA B-negative periods, exacerbation rates during NA B-positive periods are estimated to be 29% higher [95% C I: (0%, 67%)] and 18% higher [95% CI: (0%, 40%)] on the low- and high-dose IFNB arms, respectively. When NA B-positive patients again become NA B-negative, no evidence of increased exacerbation rates could then be demonstrated. More detailed exploratory analyses indicate that the effects are most evident in the approximately 20% of patients developing high titers. In these patients, the influence of NABs may be self-limited, as titers often diminish or NA Bs become undetectable with time.

Multiple sclerosis: expression of C D1a and production of IL-12 p70 and IFN-γ by blood mononuclear cells in patients on combination therapy with IFN-β and glatiramer acetate compared to monotherapy with IFN-β

Current therapy of multiple sclerosis (MS) with interferon-beta (IFN-b) or glatiramer acetate (GA) has modest effects on the course of MS. Both compounds affect several immune variables, like expression of cell surface molecules and cytokine levels. Here we compared untreated MS, therapy with IFN-b alone and combined with GA, and healthy controls (HC), regarding expression on HLA -DR+ blood mononuclear cells (MNC) of C D1a that is a cell surface molecule with capacity to present glycolipids to T cells, and of C D80 and C D86 which are costimulatory molecules that activate Th1 and Th2 responses. C ytokine production by MNC was also measured. Flow cytometry and ELISA were used. C ross-sectional comparisons revealed that untreated MS patients had higher C D1a+ HLA -DR+ MNC and lower IL-10 production compared to patients treated with IFN-b or IFN-b+G A or HC. Untreated MS patients also had higher spontaneous IFN-g and IL-12p70 production compared to MS patients treated with IFN-b+G A or HC, but not when compared to MS patients on monotherapy with IFN-b. Low C D1a+ HLA -DR+ MNC and low spontaneous production of IL-12p70 and IFN-g were more pronounced in patients treated with IFN-b+G A than with IFN-b alone. In order to clarify whether these changes reflect disease activity or treatment effects, we performed a follow up study. Nineteen MS patients with disease progression, despite monotherapy with IFN-b for more than one year, were re-examined after one to three and four to six months of treatment with IFN-b+G A. This combination therapy was associated with normalization of C D1a+ HLA -DR+ MNC, IL-12p70 and IFN-g. It remains to be shown whether these immunological changes imply a clinical benefit. Follow up studies of immune variables versus clinical effects during combined therapy of MS with IFN-b+G A are ongoing.

Elispot assay detection of cytokine secretion in multiple sclerosis patients treated with interferon-b1a or glatiramer acetate compared with untreated patients

The mechanisms behind the beneficial effects of interferon-b1a (IFN-b1a) and glatiramer acetate (GA) in the treatment of multiple sclerosis (MS) are still uncertain. A ltered cytokine patterns have been suggested including inhibition of proinflammatory cytokines like interferon-g (IFN-g) and enhancement of anti-inflammato ry cytokines such as interleukin-4 (IL-4). Twenty-nine patients with MS (10 untreated, nine treated with IFN-b1a and 10 with GA) were investigated with elispot of peripheral blood mononuclear cells. Spontaneous and myelin induced (myelin basic protein (MBP), myelin oligodendro cyte glycoprotein (MO G)-14-39 and MO G 63-87) IFN-g, IL-4, IL-5 and IL-10 secretion was studied. We found a significant reduction of spontaneous IFN-g, IL-4 and IL-5, but no difference in IL-10 secreting cells in both groups of treated patients compared with the untreated patients. Myelin-specific responses showed a significant decrease of IFN-g and an increase of IL-5, but no change in IL-4 and IL-10 secreting cells in treated compared with untreated patients. Both treatment groups revealed similar cytokine secretion patterns except for a more pronounced decrease of both spontaneous and MO G 14-39 induced IL-4 secretion in the IFN-b1a treated group. Thus, immunological effects of IFN-b1a and G A were similar showing that disease promoting Th1 (IFN-g) cells were reduced while the potentially beneficial Th2 response (IL-4) was maintained.

Qualitative and quantitative analysis of antibody response against IFNβ in patients with multiple sclerosis

To date, inter-and intra-laboratory consistency of binding assays for measuring anti-interferon (IFN)β antibodies has not been assessed. In this investigation, two independent laboratories tested a library of 80 serum specimens obtained from multiple sclerosis (MS) patients treated with IFNβ. For binding antibodies (BAbs) evaluations, each laboratory used both a capture-ELISA (cELISA) and an enzyme-immuno-assay (EIA), which is commercially available. Samples were also tested for neutralizing antibodies (NAbs). Data demonstrated good intra-laboratory reliability (rpearson≥0.86), and a good overall agreement between the results obtained from the two centers, using both the cELISA (69/80 of observed agreements) and the EIA (67/80). Accordingly, kappa coefficients (K) showed good concurrence (K ≥ 0.651). There was also substantial agreement between cELISA and EIA measurements, as performed in both centers (Orbassano, 66/80, K = 0.631; Basel, 70/80, K = 0.717). However, by comparing NAbs and BAbs titers obtained with both assays, we found that a high degree of BAb-negative samples were positive in NAb-assay. Thus, our study does not support the usefulness of ELISA-based BAb assays as a screening tool for NAbs. Otherwise, BAb-assays can be used as a confirmation test, indicating that the decrease of the biological effects is due to antibodies. In this context, both ELISA-based assays are equally reliable techniques.

Persistence of neutralizing antibodies after discontinuation of IFNβ therapy in patients with relapsing-remitting multiple sclerosis

Objective The main objective was to follow serum levels of neutralizing antibodies (NABs) against interferon-beta (IFNβ) after discontinuation of IFNβ therapy.

Background A large proportion of patients treated with recombinant IFNβ for multiple sclerosis (MS) develop therapy-induced NABs. Knowledge of persistence of NABs after discontinuation of therapy is limited. Design/patients: A retrospective follow-up study of patients treated in Denmark for relapsing-remitting (RR) MS with IFNβ for at least 12 months. NAB-positive patients, who discontinued therapy, were followed up with measurements of NABs.

Methods We measured NAB-neutralizing capacity and NAB titres a.m. Kawade using a clinically validated cytopathic effect assay.

Results Thirty-seven patients were included. Mean follow-up time was 22 months. Of the 29 patients with a NAB titre at or above 25 prior to termination of therapy, only three patients reverted to a titre below 25. Of these, two had a titre below 200 and one patient a titre of 600 at the last examination before treatment stop. The longest post-treatment follow-up during which a patient maintained NAB positivity was 59 months.

Conclusion NABs against IFNβ, especially with high titres, tend to persist for a long time after discontinuation of IFNβ therapy. NABs should always be measured before reinstitution of IFNβ treatment in NAB-positive patients.