Interferon beta in relapsing–remitting multiple sclerosis

Disease activity after discontinuation of disease-modifying therapies in patients with multiple sclerosis in Argentina: data from the nationwide registry RelevarEM

INTRODUCTION

The discontinuation of disease-modifying therapies (DMTs) in multiple sclerosis (MS) is commonly seen in real-world settings due to several factors.

AREA COVER

The aim of this study is to describe the frequency of disease activity after discontinuation of DMTs in MS patients included in the Argentinean MS and NMOSD registry.

DISCUSION

Patients with relapsing remitting MS (RRMS) and active secondary progressive MS (SPMS) were included based on the following criteria: they discontinued treatment for more than 6 months, they had been treated with a DMT for ≥2 years, and they had at least 6 months of follow-up in the registry after discontinuation. Demographic and clinical data were collected. Disease activity during follow-up was defined as the presence of a clinical relapse or a new magnetic resonance (MRI) lesion (either new lesions on T2-weighted sequence and/or contrast enhancement). Bivariate analysis was applied to identify clinical and demographic factors related to disease activity.

CONCLUSION

We included 377 patients (75.5% RRMS, 22.5% SPMS) who had discontinued DMTs. The mean (SD) follow-up after discontinuation was 15.7 (7.9) months. After discontinuation, the presence of relapse was detected in 18.8% and 3.5% in RRMS and SPMS, respectively; and new MRI activity in 22% and 3.5%, respectively. We found that higher risk of relapse and MRI activity was associated with younger age (p < 0.001), shorter disease duration (p < 0.001), and RRMS phenotype (p = 0.006). Males showed higher MRI activity (p 0.011). This study provides real-world data that can guide physicians when considering discontinuation of DMTs.

Standard Dose Weekly Intramuscular Beta Interferon-1a May Be Inadequate for Some Patients with Multiple Sclerosis: A 19-Year Clinical Experience Using Twice a Week Dosage

INTRODUCTION

Results from several clinical trials suggest there is a dose-response effect for beta interferon-1a (INFβ1a) in multiple sclerosis (MS).

METHODS

Our objective was to confirm these results through a retrospective analysis of patients with MS who had breakthrough disease (BD) on intramuscular (IM) INFβ1a (Avonex®) once per week (QW), who were switched to twice per week (BIW) IM INFβ1a between 1995 and 2015. The primary outcome measure was no further BD for at least 24 months. A secondary outcome measure was decrease in mean percentage of disease activity over time. BD was defined as continued relapses, new T2 or enhanced lesions on magnetic resonance imaging (MRI) of the brain, or worsening of the Expanded Disability Status Scale (EDSS) or the neurological examination.

RESULTS

Among 92 patients on QW IM INFβ1a, 53 patients with BD were switched to BIW IM INFβ1a. Of these 53 patients, 44 had adequate follow-up for at least 2 years. Twenty-three of these had no further BD for 24 months or more (range 24-192 months). Beta interferon neutralizing antibody testing was negative in 19 patients. An intent-to-treat analysis of the uncensored data from 52 switched patients also supported a treatment benefit.

CONCLUSION

For patients with MS having breakthrough disease on QW INFβ1a, switching to more frequently administered INFβ may be an option. Advantages to using IM INFβ1a for this include no skin reactions and a lower incidence of neutralizing antibodies. Further pragmatic, observational, larger-group studies comparing treatment with Avonex® and higher dosed IM INFβ1a, such as the recently FDA-approved IM peginterferon beta-1a, may be indicated.

Association study of promoter polymorphisms of interferon alpha and beta receptor subunit 1 (IFNAR1) gene and therapeutic response to interferon-beta in patients with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease described by inflammatory neuronal losses and resultant failures. The disease could abate by interferon-beta (IFN-β) therapy in MS patients. However, the drug response productivity is changeable between patients, and the accurate mechanism of action of the IFN-β is not obvious. The present study aims to investigate the role of interferon alpha and beta receptor subunit 1 (IFNAR1) promoter polymorphisms towards IFN-β treatment response in MS patients.

METHODS

The subjects herein were separated into either responder (n = 57) or non-responder (n = 43) groups according to IFN-β treatment and Expanded Disability Status Scale score. The Sanger sequencing method was used for genotyping.

RESULTS

Among nearly 64 Single Nucleotide Polymorphisms (SNPs), we found a significant association between the rs2850015 polymorphism and the responders and non-responders to IFN-β treatment in the recessive model of inheritance (P = 0.02). The results also revealed a significant change in the two groups of responders and non-responders to the treatment for rs36158718 as an Insertion/Deletion (INDEL) (P = 0.02). Moreover, bioinformatic analyses predicted a remarkable role for both rs2850015 and rs36158718 related to the changes of binding affinity of transcription factors and alterations in their alleles.

CONCLUSION

The present study results suggest that the genetic heterogeneity in the promoter region of IFNAR1 could affect the response to IFN-β. However, further studies with a larger sample size are needed to further demonstrate this relationship.

Maternal Type-I interferon signaling adversely affects the microglia and the behavior of the offspring accompanied by increased sensitivity to stress

Viral infection during pregnancy is often associated with neuropsychiatric conditions. In mice, exposure of pregnant dams to the viral mimetic poly(I:C), serves as a model that simulates such pathology in the offspring, through a process known as Maternal Immune Activation (MIA). To investigate the mechanism of such effect, we hypothesized that maternal upregulation of Type-I interferon (IFN-I), as part of the dam's antiviral response, might contribute to the damage imposed on the offspring. Using mRNA sequencing and flow cytometry analyses we found that poly(I:C) treatment during pregnancy caused reduced expression of genes related to proliferation and cell cycle in the offspring's microglia relative to controls. This was found to be associated with an IFN-I signature in the embryonic yolk sac, the origin of microglia in development. Neutralizing IFN-I signaling in dams attenuated the effect of MIA on the newborn's microglia, while systemic maternal administration of IFNβ was sufficient to mimic the effect of poly(I:C), and led to increased vulnerability of offspring's microglia to subsequent stress. Furthermore, maternal elevation of IFNβ resulted in behavioral manifestations reminiscent of neuropsychiatric disorders. In addition, by adopting a "two-hit" experimental paradigm, we show a higher sensitivity of the offspring to postnatal stress subsequent to the maternal IFNβ elevation, demonstrated by behavioral irregularities. Our results suggest that maternal upregulation of IFN-I, in response to MIA, interferes with the offspring's programmed microglial developmental cascade, increases their susceptibility to postnatal stress, and leads to behavioral abnormalities.

The long-term effects of disease modifying therapies on disability in people living with multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Disease modifying therapies (DMT) are a common medication class for treating people living with MS. However, although treatment with DMT can extend over more than a decade, little is known about their long-term effects. Here, we systematically review long-term (≥4 years) studies on the effect of DMT on disability progression and relapse in people living with MS.

METHODS

We searched the EMBASE and Medline databases in January 2018, using search terms that included DMT and relevant outcome measures. Two authors screened all resulting studies and evaluated the risk of bias of included studies using the ROBINS-I tool for non-randomized studies. Where there was sufficient data, we performed meta-analyses using RevMan 5. Studies that could not be included in a meta-analysis were included in data synthesis.

RESULTS

Our search returned 7,766 unique articles for review. After screening, 18 articles were included. Follow-up in these studies ranged from a mean of 3.9 years to a median of 17.8 years. Fifteen (83.3%) of the included studies had a moderate risk of bias and three (16.7%) had a serious risk of bias. Meta-analysis showed that DMT significantly reduced the risk of EDSS 6.0 and SPMS compared to no treatment.

CONCLUSION

There is some evidence that long-term treatment with interferon beta reduces the risk of EDSS 6.0 and SPMS compared to no treatment or placebo. More work is needed on the effect of second generation DMT and the relative effect of DMT on health outcomes.

Five-year outcome in the copaxone observatory: a nationwide cohort of patients with multiple sclerosis starting treatment with glatiramer acetate in France

The benefits provided by disease-modifying treatments in multiple sclerosis have been demonstrated in clinical trials, but the extent to which they can be extrapolated to everyday care is less clear, as are the long-term benefits of treatment. The objective of this prospective observational cohort study performed in France was to evaluate the effectiveness and safety of glatiramer acetate in patients with relapsing–remitting multiple sclerosis over a 5-year period. All neurologists in France were invited to participate and enroll adult patients starting a first treatment with brand glatiramer acetate 20 mg. Given the observational nature of the study, no fixed study visits were imposed; consultations took place according to the investigator’s normal practice. Occurrence of disease exacerbations and adverse events was documented and neurological disability evaluated with the EDSS at each consultation. Overall, 852 patients were analysable and 269 took glatiramer acetate continuously for 5 years. Median treatment duration was 3.4 years. Principal reasons for discontinuation were inadequate efficacy (38.9%), local tolerability (22.6%) and personal convenience (21.3%). Age, employment status, baseline EDSS score and number of previous exacerbations were variables associated with treatment persistence. The annualised exacerbation rate (5 years) was 0.41 [95% CI 0.39–0.44]; 316 patients (37.2%) remained exacerbation-free throughout. The risk of confirmed disability worsening (5 years) was 43.8% [95% CI 39.9–47.9%]. The most frequent adverse drug reactions were local injection site reactions (584 patients; 68.5%) and systemic immediate post-injection reactions (168 patients; 19.7%). Overall, these findings are consistent with those of previous clinical trials.

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.

Dimethyl fumarate in the management of multiple sclerosis: appropriate patient selection and special considerations

Delayed-release dimethyl fumarate (DMF), also known as gastroresistant DMF, is the most recently approved oral disease-modifying treatment (DMT) for relapsing multiple sclerosis. Two randomized clinical trials (Determination of the Efficacy and Safety of Oral Fumarate in Relapsing-Remitting MS [DEFINE] and Comparator and an Oral Fumarate in Relapsing-Remitting Multiple Sclerosis [CONFIRM]) demonstrated significant efficacy in reducing relapse rate and radiological signs of disease activity, as seen on magnetic resonance imaging. The DEFINE study also indicated a significant effect of DMF on disability worsening, while the low incidence of confirmed disability worsening in the CONFIRM trial rendered an insignificant reduction among the DMF-treated groups when compared to placebo. DMF also demonstrated a good safety profile and acceptable tolerability, since the most common side effects (gastrointestinal events and flushing reactions) are usually transient and mild to moderate in severity. Here, we discuss the place in therapy of DMF for individuals with relapsing multiple sclerosis, providing a tentative therapeutic algorithm to manage newly diagnosed patients and those who do not adequately respond to self-injectable DMTs. Literature data supporting the potential role of DMF as a first-line therapy are presented. The possibility of using DMF as switching treatment or even as an add-on strategy in patients with breakthrough disease despite self-injectable DMTs will also be discussed. Lastly, we argue about the role of DMF as an exit strategy from natalizumab-treated patients who are considered at risk for developing multifocal progressive leukoencephalopathy.

Postmarketing Safety Profile of Subcutaneous Interferon Beta-1a Given 3 Times Weekly: A Retrospective Administrative Claims Analysis

BACKGROUND

Health insurance administrative claims databases represent a valuable source of information regarding the safety profile of marketed products as used in actual clinical practice in a broader range of patients than that assessed in clinical trials. Interferon beta-1a administered subcutaneously 3 times weekly (IFN β-1a SC tiw), which was approved in 2002 by the FDA for the treatment of relapsing-remitting multiple sclerosis (MS), has over a decade of postmarketing experience. To date, however, its postmarketing safety profile has not been described using a real-world evidence source such as administrative claims data.

OBJECTIVE

To describe the safety profile of IFN β-1a SC tiw as presented in its U.S. prescribing information (PI) for patients with MS initiating IFN β-1a SC tiw therapy using data from U.S. health care administrative claims databases.

METHODS

This study featured an observational and retrospective "new start" cohort design using data from the Truven MarketScan Commercial and Medicare Supplemental health care administrative claims databases. Patients were eligible for inclusion if they were aged ≥ 18 years; had ≥ 1 diagnosis for MS recorded between January 1, 2006, and December 31, 2012; had ≥ 2 prescriptions for IFN β-1a SC tiw; and had ≥ 90 days of continuous eligibility pre-index date and ≥ 180 days of continuous eligibility post-index date. Patients with a prescription for IFN β-1a SC tiw without a MS diagnosis were excluded. Patients were followed from first prescription for IFN β-1a SC tiw (index date) until date of therapy switch or discontinuation, end of insurance eligibility, or end of observation period. Adverse events (AEs) examined were those listed in the Warnings and Precautions, Adverse Reactions, and Postmarketing Experience sections of the 2014 U.S. PI. Outcomes of interest were identified at the Medical Dictionary for Regulatory Activities (version 17.1) Preferred Term level and then coded to the corresponding ICD-9-CM criteria. Descriptive analyses of patient demographic, health status, health care utilization, and adherence status were performed, and incidence rates (IRs) per 100 person-years of labeled AEs with corresponding 95% CIs were calculated. The IR calculation was based on events that presented after therapy initiation and that were not present in the 90-day pre-index period.

RESULTS

The top 6 AEs included influenza-like symptoms (IR = 15.65, 95% CI = 14.96-16.36); malaise (IR = 15.33, 95% CI = 14.65-16.04; fatigue (IR = 15.02, 95% CI = 14.35-15.72); abdominal pain (IR = 10.18, 95% CI = 9.67-10.70); chest pain (IR = 8.48, 95% CI = 8.03-8.95); and depression (IR = 7.75, 95% CI = 7.32-8.20). In contrast, the 6 lowest IRs were for maculo-papular rash (IR = 0.01, 95% CI = 0.00-0.04; injection-site necrosis (IR = 0.01, 95% CI = 0.00-0.03); erythema multiforme (IR = 0.01, 95% CI = 0.00-0.04); hypoesthesia (IR = 0.00, 95% CI = 0.00-0.02); Stevens-Johnson Syndrome (IR = 0.00, 95% CI = 0.00-0.02); and xerophthalmia (IR = 0.00, 95% CI = 0.00-0.02).

CONCLUSIONS

Study results show strong convergence between the real-world safety profile of IFN β-1a SC tiw and its U.S. label. Our findings demonstrate the value of using real-world evidence obtained from administrative claims to complement clinical trial and postmarketing surveillance data in order to characterize the safety profile of established products, such as IFN β-1a SC tiw, in the postmarketing context.

Observational study assessing demographic, economic and clinical factors associated with access and utilization of health care services of patients with multiple sclerosis under treatment with interferon beta-1b (EXTAVIA)

Multiple sclerosis (MS) results in an extensive use of the health care system, even within the first years of diagnosis. The effectiveness and accessibility of the health care system may affect patients' quality of life. The aim of the present study was to evaluate the health care resource use of MS patients under interferon beta-1b (EXTAVIA) treatment in Greece, the demographic or clinical factors that may affect this use and also patient satisfaction with the health care system. Structured interviews were conducted for data collection. In total, 204 patients (74.02% females, mean age (SD) 43.58 (11.42) years) were enrolled in the study. Analysis of the reported data revealed that during the previous year patients made extensive use of health services in particular neurologists (71.08% visited neurologists in public hospitals, 66.67% in private offices and 48.53% in insurance institutes) and physiotherapists. However, the majority of the patients (52.45%) chose as their treating doctor private practice neurologists, which may reflect accessibility barriers or low quality health services in the public health system. Patients seemed to be generally satisfied with the received health care, support and information on MS (84.81% were satisfied from the information provided to them). Patients' health status (as denoted by disease duration, disability status and hospitalization needs) and insurance institute were found to influence their visits to neurologists. Good adherence (up to 70.1%) to the study medication was reported. Patients' feedback on currently provided health services could direct these services towards the patients' expectations.

Identifying responders and nonresponders to interferon therapy in multiple sclerosis

Interferon beta is a well established disease-modifying agent used for relapsing-remitting multiple sclerosis. Despite treatment, a relevant proportion of patients continue to experience clinical (ie, relapses, worsening of disability) and magnetic resonance imaging (MRI) activity. Early identification of responders and nonresponders to interferon beta is strongly recommended to select patients who need a prompt switch to another disease-modifying agent and to ultimately avoid accumulation of fixed disability over time. Detecting responders and nonresponders to interferon beta can be challenging, mainly because of the lack of a clear and shared clinical definition of response to treatment. Clinical features at the start of treatment should be considered as prognostic factors, but MRI parameters assessed during treatment, such as contrast-enhancing lesions or new T2-hyperintense lesions, may be sensitive markers of response to interferon beta. Quantitative scoring systems derived from a combination of relapses and MRI activity have recently been proposed as practical tools for use in the everyday clinical setting. Blood biomarkers, such as neutralizing antibodies to interferon beta and Myxovirus resistance protein A, provide further useful information for detecting responders and nonresponders to interferon beta. However, since the presence of neutralizing antibodies can only partially explain the nonresponse to interferon beta, biomarkers of interferon beta activity possibly related to the pathogenesis of the disease could represent a future step toward a tailored, long-lasting effective treatment against multiple sclerosis.

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

Systematic review of disease-modifying therapies to assess unmet needs in multiple sclerosis: tolerability and adherence

Reviews of therapeutic drugs usually focus on the highly selected and closely monitored patient populations from randomized controlled trials. The objective of this study was to review systematically the tolerability and adherence of multiple sclerosis disease-modifying therapies, using data from both randomized controlled trials and observational settings. Relevant literature was identified using predefined search terms, and adverse event and study discontinuation data were extracted and categorized according to study type (randomized controlled trial or observational) and study duration. A total of 151 papers were selected for analysis; 33% were classified as randomized controlled trials and 62% as observational studies. Most of the papers concerned interferon preparations and glatiramer acetate; the limited available information on mitoxantrone and natalizumab precluded extensive examination of these. The most common adverse events were flu-like symptoms (interferon therapies only) and injection-site reactions. Mean discontinuation rates ranged from 16% to 27%. There were no marked differences in tolerability or adherence data from randomized controlled trials and observational studies, but the incidence of adverse events remained high in lengthy studies and discontinuations accumulated with time. The present systematic review of randomized clinical trial and observational data highlights the tolerability and adherence issues associated with commonly used first-line multiple sclerosis treatments.

The interferon beta therapies for treatment of relapsing-remitting multiple sclerosis: are they equally efficacious? A comparative review of open-label studies evaluating the efficacy, safety, or dosing of different interferon beta formulations alone or in combination

Interferon beta preparations are the most widely used initial therapies prescribed for patients with relapsing-remitting multiple sclerosis. Phase III studies have demonstrated comparable efficacy on clinical measures of disease activity, variable benefits on radiological measures, and good overall tolerability. Subsequent clinical studies have attempted to compare directly the three available interferon beta preparations, reporting both safety and efficacy data. We review the literature on studies evaluating interferon beta therapy for patients with relapsing-remitting multiple sclerosis, discuss reasons for discrepant findings, and assess the utility of interferon beta-based combination regimens as the focus of future studies in the increasingly complex multiple sclerosis therapy landscape.

Management of breakthrough disease in patients with multiple sclerosis: when an increasing of Interferon beta dose should be effective?

Background

In daily clinical setting, some patients affected by relapsing-remitting Multiple Sclerosis (RRMS) are switched from the low-dose to the high-dose Interferon beta (IFNB) in order to achieve a better control of the disease.

Purpose

In this observational, post-marketing study we reported the 2-year clinical outcomes of patients switched to the high-dose IFNB; we also evaluated whether different criteria adopted to switch patients had an influence on the clinical outcomes.

Methods

Patients affected by RRMS and switched from the low-dose to the high-dose IFNB due to the occurrence of relapses, or contrast-enhancing lesions (CELs) as detected by yearly scheduled MRI scans, were followed for two years. Expanded Disability Status Scale (EDSS) scores, as well as clinical relapses, were evaluated during the follow-up period.

Results

We identified 121 patients switched to the high-dose IFNB. One hundred patients increased the IFNB dose because of the occurrence of one or more relapses, and 21 because of the presence of one or more CELs, even in absence of clinical relapses. At the end of the 2-year follow-up, 72 (59.5%) patients had a relapse, and 51 (42.1%) reached a sustained progression on EDSS score. Overall, 85 (70.3%) patients showed some clinical disease activity (i.e. relapses or disability progression) after the switch.

Relapse risk after increasing the IFNB dose was greater in patients who switched because of relapses than those switched only for MRI activity (HR: 5.55, p = 0.001). A high EDSS score (HR: 1.77, p < 0.001) and the combination of clinical and MRI activity at switch raised the risk of sustained disability progression after increasing the IFNB dose (HR: 2.14, p = 0.01).

Conclusion

In the majority of MS patients, switching from the low-dose to the high-dose IFNB did not reduce the risk of further relapses or increased disability in the 2-year follow period.

Although we observed that patients who switched only on the basis on MRI activity (even in absence of clinical attacks) had a lower risk of further relapses, larger studies are warranted before to recommend a switch algorithm based on MRI findings.

Immunomodulatory drug treatment in multiple sclerosis

The fundamental role of inflammatory immune processes in the pathology of multiple sclerosis (MS) provides the rationale for immunomodulatory therapies that attempt to shift the immune system from pro-inflammatory to anti-inflammatory pathways and induce regulatory mechanisms. Growing understanding of immune cellular and molecular mechanisms together with modern biotechnology engendered promising immunomodulatory treatment strategies, with novel mechanisms of actions and different levels of specificity. These include inhibitory molecules, monoclonal antibodies, cell therapies and agents that are administered orally or by infrequent infusions. Several of these treatments have demonstrated impressive efficacy in Phase II and III clinical trials by reducing disease activity and accumulation of disability. However, with the advent of potent therapies, rare but severe adverse effects, such as CNS infections and malignancies, have occurred. This article describes current and upcoming immunomodulatory strategies for MS therapy. The potential of immunomodulatory treatments to counteract the inflammatory characteristics of MS and support neuroprotective processes is discussed.

Update on the treatment options for multiple sclerosis

Recent progress in the treatment of multiple sclerosis (MS) is remarkable, and the introduction of new therapies is yielding improvements in the management of MS. Furthermore, clinical trials with many different types of agents, especially selected monoclonal antibodies, have been undertaken or are ongoing, and some of the agents involved will probably be available as treatments for MS in the near future. Although these new and promising agents include targeted immunotherapies, some of them have limitations such as associated severe adverse events and the development of neutralizing antibodies. With regard to risk-benefit ratios, pharmacogenetics could shed light on inherited differences in drug metabolism and response, which would make individualized therapy possible in MS. Here, we review the recent progress in current therapeutic strategies for MS, and the potential options for future MS treatment.

Current therapeutic recommendations in multiple sclerosis

Recent clinical studies in multiple sclerosis have provided new data on glatiramer acetate, interferon-beta preparations and natalizumab, which will have important implications for optimising patient care. Once a diagnosis has been made with confidence, early initiation of immunotherapy is warranted because of the presence of continuous inflammatory disease activity. Approval for therapy in patients with a clinically isolated syndrome has been granted to several first-line treatments, and most recently to glatiramer acetate. The utility of systematic frequent MRI monitoring of disease activity and response to therapy is not yet clearly established. Treatment efficacy after initiating therapy at the first demyelinating episode has to be followed carefully and re-evaluated whenever necessary. The occurrence of further relapses, confirmed disability progression or MRI evidence of persistent or aggravated disease activity would be regarded as evidence for an inadequate treatment response. However, limitations of clinical scores in faithfully reflecting disease activity at all times, as well as uncertainties about the discriminatory capacity of surrogate measures such as MRI, need to be clarified before clear-cut recommendations on treatment failure can be advocated. Escalation therapy is reserved for patients presenting with 'aggressive disease', which can be operationally defined as the occurrence of two severe relapses within twelve months, together with either MRI evidence for persistent disease activity or a two-point progression of disability on the EDSS.

Non-adherence to interferon-beta therapy in Swedish patients with multiple sclerosis

OBJECTIVES

To explore the occurrence and reasons for stopping, switching or continuing first prescribed interferon-beta therapy in patients with multiple sclerosis in Sweden, with respect to demographic, clinical and/or therapy-related factors.

MATERIALS AND METHODS

A retrospective study reviewing the medical charts of 259 patients with multiple sclerosis, comparing patients continuing therapy for at least 3 years with those switching or stopping therapy.

RESULTS

Sixty 9% stopped (15%), or switched (54%), interferon-beta therapy within 3 years. Stoppers had longer disease duration before starting therapy (P = 0.002), less frequently relapsing-remitting multiple sclerosis (P = 0.046), and more often Expanded Disability Status Scale scores 6-9.5 (P = 0.045) compared to Switchers. The most common reasons for switching/stopping therapy were perceived lack of effect and side-effects.

CONCLUSIONS

Adherence to initial immune-modulating therapy is low; identification of patients at higher risk of stopping therapy and provision of adequate support are essential.

One-year MRI scan predicts clinical response to interferon beta in multiple sclerosis

BACKGROUND AND PURPOSE

To define the predictive value of clinical and magnetic resonance imaging (MRI) characteristics in identifying relapsing-remitting multiple sclerosis (RR-MS) patients with sustained disability progression during interferon beta (IFNB) treatment.

METHODS

All patients receiving treatment with one of the available IFNB formulations for at least 1 year were included in this single-centre, prospective and post-marketing study. Demographic, clinical and MRI data were collected at IFNB start and at 1 year of therapy; patients were followed-up at least yearly. Poor clinical response was defined as the occurrence of a sustained disability progression of > or =1 point in the Expanded Disability Status Scale (EDSS) during the follow-up period.

RESULTS

Out of 454 RR-MS patients starting IFNB therapy, data coming from 394 patients with a mean follow-up of 4.8 (2.4) years were analysed. Sixty patients were excluded because of too short follow-up. Less than 1/3 (30.4%) of the patients satisfied the criterion of 'poor responders'. Patients presenting new lesions on T2-weighted MRI scan after 1 year of therapy (compared with baseline) had a higher risk of being poor responder to treatment with IFNB during the follow-up period (HR 16.8, 95% CI 7.6-37.1, P < 0.001). An augmented risk increasing the number of lesions was observed, with a 10-fold increase for each new lesion.

CONCLUSIONS

Developing new T2-hyperintense lesions during IFNB treatment was the best predictor of long-term poor response to therapy. MRI scans performed after 1 year of IFNB treatment may be useful in contributing to early identification of poor responders.

High-dose, high-frequency recombinant interferon beta-1a in the treatment of multiple sclerosis

BACKGROUND

There is at present no cure for multiple sclerosis (MS), and existing therapies are designed primarily to prevent lesion formation, decrease the rate and severity of relapses and delay the resulting disability by reducing levels of inflammation.

OBJECTIVE

The aim of this review was to assess the treatment of relapsing MS with particular focus on subcutaneous (s.c.) interferon (IFN) beta-1a.

METHOD

The literature on IFN beta-1a therapy of MS was reviewed based on a PubMed search (English-language publications from 1990) including its pharmacodynamics and pharmacokinetics, clinical efficacy in relapsing MS as shown in placebo-controlled studies and in comparative trials, efficacy in secondary progressive MS, safety and tolerability, and the impact of neutralizing antibodies.

CONCLUSION

The literature suggests that high-dose, high-frequency s.c. IFN beta-1a offers an effective option for treating patients with relapsing MS, with proven long-term safety and tolerability, and has a favourable benefit-to-risk ratio compared with other forms of IFN beta.

Basic and escalating immunomodulatory treatments in multiple sclerosis: current therapeutic recommendations

This review updates and extends earlier Consensus Reports related to current basic and escalating immunomodulatory treatments in multiple sclerosis (MS). The recent literature has been extracted for new evidence from randomized controlled trials, open treatment studies and reported expert opinion, both in original articles and reviews, and evaluates indications and safety issues based on published data. After data extraction from published full length publications and critically weighing the evidence and potential impact of the data, the review has been drafted and circulated within the National MS Societies and the European MS Platform to reach consensus within a very large group of European experts, combining evidence-based criteria and expert opinion where evidence is still incomplete. The review also outlines a few areas of controversy and delineates the need for future research.

Review of the clinical evidence for interferon beta 1a (Rebif) in the treatment of multiple sclerosis

Interferon (INF) beta 1a 22 or 44 mug (Rebif((R))) administered s.c. 3 times a week (t.i.w) is a well established immunomodulating treatment for relapsing remitting multiple sclerosis (RRMS). This review focuses on its mechanisms of action, evidence of efficacy, safety, and tolerability. Several pharmacodynamic properties explain the immunomodulatory actions of INF beta 1a 22 or 44 mug s.c. t.i.w. Pivotal trials and post-marketing studies proved that the drug is effective in reducing disease activity and likely in slowing disease progression. Head-to-head comparative studies with other marketed INFs beta in RRMS suggested a better therapeutic response associated with higher doses and frequency of administration of Rebif((R)). Additional evidence indicated a beneficial effect of INF beta 1a in patients with clinically isolated syndromes (CIS) suggestive of MS, as treatment reduced time to conversion to clinically definite (CD) disease. Further, although the drug did not prove to slow time to progression there were benefits on relapse- and MRI-related secondary outcome measures in secondary progressive (SP) MS. Pivotal trials, their cross-over extensions, and post-marketing studies consistently showed that INF beta 1a 22 or 44 mug s.c. t.i.w. is safe and well tolerated, as adverse drug reactions are usually mild and manageable.

Efficacy and tolerability of intramuscular interferon beta-1a compared with subcutaneous interferon beta-1a in relapsing MS: results from PROOF

OBJECTIVE

Benefits from interferon beta (IFNbeta treatment in patients with multiple sclerosis are affected by many factors, including sustained clinical efficacy, acceptable tolerability, adherence to therapy, and the development of neutralizing antibodies (NAbs). The Prospective and Retrospective Long-Term Observational Study of Avonex and Rebif (PROOF) was designed to compare the relative efficacy and tolerability of the two IFNbeta-1a products for up to 5 years.

METHODS

PROOF compared the relative efficacy and tolerability of intramuscular (IM) IFNbeta-1a (Avonex) 30 microg once weekly (n = 69) and subcutaneous (SC) IFNbeta-1a (Rebif) 44 microg three times per week (n = 67). The duration of the retrospective portion of the study was 12-24 months. Due to slow enrollment, PROOF ended earlier than planned and the final duration of the prospective portion of the study was 6 months. Therefore, between 18 and 30 months of efficacy and tolerability data were available for analysis.

RESULTS

After controlling for baseline disability level, Expanded Disability Status Scale (EDSS) scores revealed no statistically significant differences between the treatment groups during the prospective portion of the study, with sustained disability progression similar in both groups (25.8% IM IFNbeta-1a 30 mug once weekly vs. 26.7% SC IFNbeta-1a 44 mug three times per week). Relapse rates were similar in the groups, as were MRI endpoints of brain parenchymal fraction, T1 lesion volume, T2 lesion volume, number of new/enlarging T2 lesions, and gadolinium-enhancing (Gd+) lesion volume and count. Treatment groups differed in frequency of NAbs, with 19% of patients treated with SC IFNbeta-1a 44 microg three times per week NAb+ compared with none treated with IM IFNbeta-1a 30 microg once weekly. More NAb+ patients compared with NAb- patients had disability progression (40.0% vs. 27.8%, p = NS), new or enlarging T2 lesions at the end of treatment (63.6% vs. 40.7%, p = 0.003), and Gd+ lesions after 12-24 months of treatment (36.4% vs. 15%, p = 0.001). The IFNbeta-1a products had comparable tolerability. However, fewer patients treated with IM IFNbeta-1a 30 microg once weekly had injection-site reactions (2.9% vs. 6.0%). Limitations of this study include its design and sample size, both of which hinder detection of differences in efficacy between IFNbeta-1a treatments.

CONCLUSIONS

The results of the present study show that the two IFNbeta-1a products have comparable efficacy and differing immunogenicity.

[Subcutaneous interferon-beta-1a in the treatment of multiple sclerosis]

During the last 10 years recombinant interferon-beta-1a administered subcutaneously has been the subject of several clinical trials in relapsing remitting multiple sclerosis (RRMS), in secondary progressive MS (SPMS), as well as in clinically isolated syndromes. All of them met the criteria of evidence level class I. Consistent evidence for moderate immunomodulatory effects on clinical parameters of disease activity was gained, and even higher efficacy of IFN-beta-1a sc. on MRI activity of multiple sclerosis was proven. Indirect evidence confirmed the hypothesis of a dose-response curve for IFN-beta-1a formulations in MS. The higher efficacy of IFN-beta-1a 44 microg sc. TIW, however, also includes more adverse events such as injection site reactions, flu-like symptoms and a moderate immunogenicity. Current evidence does not allow a recommendation of IFN-beta-1a sc. as most effective first line therapy, because also the individual patient's choice in the route of administration and long-term effects of neutralizing antibodies to IFN-beta-1a sc. must be taken into account. In the long-term, IFN-beta-1a showed a beneficial safety-tolerability profile with 50 % of patients sticking to the initial immunomodulatory treatment. There were no teratogenic effects, IFN-beta-1a sc. did not enhance depressive symptoms. Data on inhibition of the progression of disease, however, remained inconclusive. Probable beneficial effects of IFN-beta-1a sc. on cognitive function or "chronic fatigue" have not been investigated yet.

Predictive role of evoked potential examinations in patients with clinically isolated optic neuritis in light of the revised McDonald criteria

To analyse the sensitivity and role of somatosensory and motor evoked potentials (EP) in patients with a first episode of clinically isolated optic neuritis (ON) in predicting the development and course of multiple sclerosis (MS), 27 patients with ON underwent EP and magnetic resonance imaging (MRI) examinations at presentation. Follow-up MRI scans were also performed (mean: 20, range: 4-48 months). It was found that 2/27 patients did not fulfill the MRI (McDonald) and clinical criteria of MS upon follow-up and also had normal EP results. Abnormal EP results were found in 6/27 patients and all of them had follow-up MRI results fulfilling the revised McDonald criteria of MS; 4/6 patients in this group were also diagnosed as clinically definitive MS. The majority, 19/27 patients had normal EP results, but went on to develop MS based on follow-up MRI results and McDonald criteria. Of these patients, however, only 3/19 converted to clinically definitive MS as well. The baseline MRI was abnormal in similar proportions (4/6 and 12/19) in these last two groups of patients. Thus, abnormal EP examinations at the first episode of ON can be considered as a predictive factor only for the earlier clinical conversion to MS - in this respect, however, being more sensitive than the initial MRI - and as such they may contribute to the delineation of the patient group who may benefit from early immunomodulatory treatment. They do not however have a predictive value for the development of MS itself as diagnosed by the McDonald criteria.

Outcome of beta-interferon treatment in relapsing-remitting multiple sclerosis: a Bayesian analysis

Observational studies of the effect of beta-interferon (IFNbeta) on accumulation of fixed disability in relapsing remitting multiple sclerosis (RRMS) in clinical practice have been difficult to interpret due to bias. The aim of this study of 175 RRMS patients was to use Bayesian analysis to establish whether IFNbeta attenuates disability relative to a cohort of matched historical control subjects from the Sylvia Lawry Centre for MS Research. A sensitivity analysis was based on a range of prior probability distributions for IFNbeta efficacy derived from a published meta-analysis of randomised controlled trials (RCTs) of IFNbeta, and the data were interpreted both unmodified and using variance inflation and point estimate bias correction; the corrected data interpreted in the light of the most likely prior probability distribution yielded a 95 % posterior credible interval for the odds ratio of accumulation of fixed disability after two years of IFNbeta therapy of 0.52, 0.94. It is concluded that two years of IFNbeta therapy for RRMS reduces accumulation of fixed disability in clinical practice.

MS treatment: postmarketing studies

Multiple sclerosis (MS) is an inflammatory chronic demyelinating disease. Nowadays, there are several registered drugs aimed to control the disease activity. Because these drugs are given parenterally for years, it is of utmost importance to attain maximum adherence to treatment through close and permanent care of patients. The efficacy of the different registered drugs has been compared against placebo. Observational and head-to-head studies have shown controverted results in the degree of efficacy between the products. Despite the efficacy reported, a high proportion of patients will have a lack of response to treatment. Early identification of these patients is therefore essential in order to attempt other therapeutic approaches.

Syndromes and complications of interferon therapy

PURPOSE OF REVIEW

Interferons are used to treat a variety of medical conditions. They are integral players in immunity and a number of immune-mediated complications can arise during interferon therapy. We have reviewed the occurrence of these complications, and the mechanisms behind them.

RECENT FINDINGS

Case reports and follow-up studies of large cohorts of patients on interferon therapy have confirmed that immune-mediated complications are uncommon but can occur in a number of different organ systems. IFNalpha production is induced by specific autoantibody-nuclear antigen immune complexes, and has a key role in the development and maintenance of autoimmunity in systemic lupus erythematosus.

SUMMARY

Interferon therapy can precipitate immune-mediated abnormalities de novo or can exacerbate an existing autoimmune tendency. This is manifest in the rise in titre of existing antibodies and in the development of clinical disease in patients with preexisting antibodies. Type I interferons have a key role in the development of systemic lupus erythematosus.

Quality Assessment in Multiple Sclerosis Therapy (QUASIMS)

Interferon beta (IFN beta) preparations are the most frequently prescribed therapies for patients with relapsing multiple sclerosis (MS). Several open-label observational studies report similar efficacy among IFN beta preparations. The Quality Assessment in Multiple Sclerosis Therapy (QUASIMS) study is a large, open-label observational study designed to compare the effectiveness and tolerability of available IFN beta preparations as disease-modifying therapies for relapsing MS across a wide range of clinical practice settings. This retrospective, controlled cohort study was conducted by chart review at 510 sites in Germany, Austria, and Switzerland. Enrolled patients had received one of the four available IFN beta preparations/dosing regimens (intramuscular IFN beta-1a 30 microg 1x/week [Avonex], subcutaneous (SC) IFN beta-1a 22 or 44 microg 3 x/week [Rebif], or SC IFN beta-1b 250 microg 3.5x/week [Betaferon/Betaseron]) for >or= 2 years. Pre-planned outcomes at 1 and 2 years included change from baseline Expanded Disability Status Scale (EDSS) score, percentage of progression-free patients (< 1.0 EDSS point), annualised relapse rate (RR), percentage of relapse-free patients, and reasons for therapy change. Of 4754 evaluable patients, 3991 (84%) received IFN beta as initial therapy. There were no significant differences among IFN betas when used as initial or follow-up therapy on almost all outcome variables. Relapse rate was consistently higher and percentage of relapse-free patients consistently lower for all products used as follow-up versus initial therapy. Results of QUASIMS showed similar effectiveness among IFN beta products. Benefits were consistently superior when IFN beta was used as initial rather than follow-up therapy. Our results suggest that patients do not benefit in terms of disease outcome from switching between IFN beta preparations/dosing regimens.

Immunmodulatorische Stufentherapie der Multiplen Sklerose

The updated recommendations presented here reflect new developments in the diagnostic work-up and immunotherapy of multiple sclerosis (MS) as well as optimization of medical care for MS patients. Monoclonal antibodies provide considerable improvement of treatment, but their use in basic therapy is restricted by their side effect profile. Thus, for the time being, natalizumab is only approved for monotherapy after basic treatment has failed or for rapidly progressive relapsing-remitting MS. In contrast, long-term data on recombinant beta-interferons and glatiramer acetate (Copaxone) show that even after several years no unexpected side effects occur and that a prolonged therapeutic effect can be assumed which correlates with the dose or frequency of treatment. Recently IFN-beta1b (Betaferon) was approved for prophylactic treatment after the first attack (clinically isolated syndrome, CIS). During treatment with beta-interferons, neutralizing antibodies can emerge with possible loss of effectivity. In contrast, antibodies play no role in treatment with glatiramer acetate. During or after therapy with mitoxantrone, serious side effects (cardiomyopathy, acute myeloid leukemia) appeared in 0.2-0.4% of cases. Plasmapheresis is limited to individual curative attempts in escalating therapy of a severe attack. According to the revised McDonald criteria, the diagnosis of MS can be made as early as the occurrence of the first attack (CIS). Recommendations for optimized care of MS patients are also new, thus implementing a resolution of the European Parliament.

Neutralising antibodies to IFN-β in patients with multiple sclerosis

The development of neutralising antibodies (NABs), or neutralising activity in the absence of NABs, is a potential complication of therapy with interferon (IFN)-beta for patients with multiple sclerosis, limiting therapeutic efficacy. Discontinuation of IFN-beta therapy in patients found to have sustained titres of NABs > 1:100 over an interval of 3 - 6 months has been recently proposed as a Level A recommendation. The extent to which NABs are causative, rather than an epiphenomenon, in determining drug failure has been a matter of numerous investigations and is still controversial. Thus, further studies are warranted for determining the role that NABs may play in reducing the response to the drug. In particular, the effects of NABs in reducing the efficacy of IFN-beta therapy beyond clinical relapse rate and lesion load on conventional imaging are not as yet fully understood.

Comparison of Betaferon, Avonex, and Rebif in treatment of relapsing-remitting multiple sclerosis

OBJECTIVES

To compare the relative efficacies of Betaferon, Avonex, and Rebif in the treatment of relapsing-remitting multiple sclerosis (RRMS).

METHODS

Ninety patients with RRMS were randomly allocated to the three treatment groups. The first group received Betaferon, the second group received Avonex, and the third group received Rebif for 24 months. Response to treatment was assessed at 6, 12, and 24 months after start of therapy.

RESULTS

Of the 30 patients treated with Betaferon, the mean (standard deviation, SD) of relapse rate decreased from 2.2 (0.7) to 0.7 (0.7) episodes. Correspondingly, in the 30 patients treated with Avonex, the mean (SD) of relapse rate decreased from 2.0 (1.2) to 1.2 (0.9) (P < 0.001). In the 30 patients treated with Rebif, the mean (SD) of relapse rate decreased from 2.4 (1.0) to 0.6 (0.9) (P < 0. 01). After 2 years, 43.3% of patients receiving Betaferon and 56.7% of patients receiving Rebif remained relapse-free compared with 20% of those given Avonex. Expanded Disability Status Scale (EDSS) decreased by 0.7 U in Betaferon-treated patients (P < 0.001), 0.3 U in Rebif-treated patients (P < 0.05), and remained stable in Avonex patients.

CONCLUSION

Treatment with Betaferon, Avenox, and Rebif significantly reduce relapse rate and EDSS score in patients with RRMS.

Effects of interferon beta-1a and -1b over time: 6-year results of an observational head-to-head study

OBJECTIVE

To evaluate and compare the long-term efficacy and safety of two different beta-interferon preparations (IFN-beta-1a vs IFN-beta-1b).

MATERIALS AND METHODS

Two parallel outpatient groups with relapsing-remitting multiple sclerosis (RRMS), according to Poser criteria, were treated with either intramuscular IFN-beta-1a 30 microg (group A, n = 62) or subcutaneous IFN-beta-1b 250 microg (group B, n = 64).

RESULTS

A statistically significant reduction was seen in the relapse rate (P < 0.0001) in both groups. No significant difference was found between the two groups (P = 0.43). After 6 years of therapy, the mean Expanded Disability Status Scale score was 3.22 +/- 1.47 (delta 1.03 +/- 1.35) in group A and 3.34 +/- 1.47 (delta 0.97 +/- 1.47) in group B (P = 0.47).

CONCLUSIONS

Our study results suggest that the efficacy of IFN-beta-1a 30 microg once weekly and SC IFN-beta-1b 250 microg every other day is similar. Both IFN-beta-1a and IFN-beta-1b are effective in slowing disability progression.