Enhanced Benefit of Increasing Interferon Beta-1a Dose and Frequency in Relapsing Multiple Sclerosis

COVID-19 Vaccine Response in People with Multiple Sclerosis Treated with Dimethyl Fumarate, Diroximel Fumarate, Natalizumab, Ocrelizumab, or Interferon Beta Therapy

BACKGROUND

Some multiple sclerosis (MS) disease-modifying therapies (DMTs) impair responses to vaccines, emphasizing the importance of understanding COVID-19 vaccine immune responses in people with MS (PwMS) receiving different DMTs.

METHODS

This prospective, open-label observational study enrolled 45 participants treated with natalizumab (n = 12), ocrelizumab (n = 16), fumarates (dimethyl fumarate or diroximel fumarate, n = 11), or interferon beta (n = 6); ages 18-65 years inclusive; stable on DMT for at least 6 months. Responder rates, anti-SARS-CoV-2 spike receptor-binding domain IgG (anti-RBD) geometric mean titers (GMTs), antigen-specific T cells, and vaccination-related adverse events were evaluated at baseline and 8, 24, 36, and 48 weeks after first mRNA-1273 (Moderna) dose.

RESULTS

At 8 weeks post vaccination, all natalizumab-, fumarate-, and interferon beta-treated participants generated detectable anti-RBD IgG titers, compared to only 25% of the ocrelizumab cohort. At 24 and 36 weeks post vaccination, natalizumab-, fumarate-, and interferon beta-treated participants continued to demonstrate detectable anti-RBD IgG titers, whereas participants receiving ocrelizumab did not. Anti-RBD GMTs decreased 81.5% between 8 and 24 weeks post vaccination for the non-ocrelizumab-treated participants, with no significant difference between groups. At 36 weeks post vaccination, ocrelizumab-treated participants had higher proportions of spike-specific T cells compared to other treatment groups. Vaccine-associated side effects were highest in the ocrelizumab arm for most symptoms.

CONCLUSIONS

These results suggest that humoral response to mRNA-1273 COVID-19 vaccine is preserved and similar in PwMS treated with natalizumab, fumarate, and interferon beta, but muted with ocrelizumab. All DMTs had preserved T cell response, including the ocrelizumab cohort, which also had a greater risk of vaccine-related side effects.

Comparison of Therapies in MS Patients After the First Demyelinating Event in Real Clinical Practice in the Czech Republic: Data From the National Registry ReMuS

Background: Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system. Well-established drugs used for MS patients after the first demyelinating event in the Czech Republic include glatiramer acetate (GA), interferon beta-1a (IFNβ-1a), IFN beta-1b (IFNβ-1b), peginterferon beta-1a (peg-IFNβ-1a), and teriflunomide.

Objective: The objective of this observational study was to compare the effectiveness of the abovementioned drugs in patients with MS who initiated their therapy after the first demyelinating event. Patients were followed for up to 2 years in real clinical practice in the Czech Republic.

Methods: A total of 1,654 MS patients treated after the first demyelinating event and followed up for 2 years were enrolled. Evaluation parameters (endpoints) included the annualized relapse rate (ARR), time to next relapse, change in the Expanded Disability Status Scale (EDSS) score, and time of confirmed disease progression (CDP). When patients ended the therapy before the observational period, the reason for ending the therapy among different treatments was compared.

Results: No significant difference was found among the groups of patients treated with IFNβ-1a/1b, GA, or teriflunomide for the following parameters: time to the first relapse, change in the EDSS score, and the proportion of patients with CDP. Compared to IFNβ-1a (44 mcg), a significant increase in the percentage of relapse-free patients was found for GA, but this treatment effect was not confirmed by the validation analysis. Compared to the other drugs, there was a significant difference in the reasons for terminating GA therapy.

Conclusion: Small differences were found among GA, IFNβ and teriflunomide therapies, with no significant impact on the final outcome after 2 years. Therefore, in clinical practice, we recommend choosing the drug based on individual potential risk from long-term therapy and on patient preferences and clinical characteristics.

Clinical Parameters to Predict Future Clinical Disease Activity After Treatment Change to Higher-Dose Subcutaneous Interferon Beta-1a From Other Platform Injectables in Patients With Relapsing-Remitting Multiple Sclerosis

Objective: To identify predictors of clinical disease activity after treatment change to higher-dose interferon beta-1a in relapsing-remitting multiple sclerosis (MS).

Methods: This was a retrospective-prospective observational multicenter study. We enrolled patients with at least one relapse on platform injectable therapy who were changed to 44 μg interferon beta-1a. Our primary endpoint was the clinical disease activity-free (cDAF) status at 6, 12, 18, and 24 months. Secondary endponts included relapse-free status and disability progression-free status at different timepoints. The primary predictor of interest was the monosymptomatic vs. polysymptomatic index relapse, based on the number of affected functional systems from the Kurtzke scale during the last relapse prior to baseline. Other secondary predictors of clinical disease activity were analyzed based on different demographic and relapse characteristics. Kaplan-Meier estimates of the cumulative probability of remaining in cDAF status were performed. The time to clinical disease activity was compared between groups using univariate Kaplan-Meier analysis and multivariate Cox regression. Multivariate analyses were processed in the form of CART (Classification & Regression Trees).

Results: A total of 300 patients entered the study; 233 (77.7%) of them completed the 24-month study period and 67 patients (22.3%) terminated early. The proportion of patients in cDAF status was 84.7, 69.5, 57.5, and 54.2% at 6, 12, 18, and 24 months. After 2 years of follow-up, 55.9% of patients remained relapse-free and 87.8% of patients remained disability progression-free. At all timepoints, the polysymptomatic index relapse was the most significant predictor of clinical disease activity of all studied variables. Hazard ratio of cDAF status for patients with monosymptomatic vs. polysymptomatic index relapse was 1.94 (95% CI 1.38–2.73). CART analyses also confirmed the polysymptomatic index relapse being the strongest predictor of clinical disease activity, followed by higher number of pre-baseline relapses with the most significant effect in the monosymptomatic index relapse group. The next strongest predictors of clinical disease activity were cerebellar syndrome as the most disabled Kurtzke functional system for the monosymptomatic relapse group, and age at first MS symptom ≥ 45 for the polysymptomatic relapse group.

Conclusions: Patients with a polysymptomatic index relapse and/or higher number of relapses within 2 years prior to baseline are at high risk of clinical disease activity, despite treatment change to higher-dose interferon beta-1a from other platform injectable therapy.

Trial registration: State Institute of Drug Control (SUKL), URL: http://www.sukl.eu/modules/nps/index.php?h=study&a=detail&id=958&lang=2, registration number 1205090000.

Structure-Based Specific Detection and Inhibition of Monoamine Oxidases and Their Applications in Central Nervous System Diseases

Monoamine oxidases (MAOs) are the enzymes that catalyze the oxidation of monoamines, such as dopamine, norepinephrine, and serotonin, which serve as key neurotransmitters in the central nervous system (CNS). MAOs play important roles in maintaining the homeostasis of monoamines, and the aberrant expression or activation of MAOs underlies the pathogenesis of monoamine neurotransmitter disorders, including neuropsychiatric and neurodegenerative diseases. Clearly, detecting and inhibiting the activities of MAOs is of great value for the diagnosis and therapeutics of these diseases. Accordingly, many specific detection probes and inhibitors have been developed and substantially contributed to basic and clinical studies of these diseases. In this review, progress in the detecting and inhibiting of MAOs and their applications in mechanism exploration and treatment of neurotransmitter-related disorders is summarized. Notably, how the detection probes and inhibitors of MAOs were developed has been specifically addressed. It is hoped that this review will benefit the design of more effective and sensitive probes and inhibitors for MAOs, and eventually the treatment of monoamine neurotransmitter disorders.

Tolerability, treatment satisfaction and quality of life outcomes in stable multiple sclerosis patients switched from injectable therapies to auto injected intramuscular interferon beta 1a: The SFERA study

BACKGROUND

Interferon beta (IFNB) and Glatiramer acetate, long-term first line disease modifying treatments (DMTs) for multiple sclerosis (MS), have different injection frequencies crucial for injection site related side effects. We aimed at investigating whether switching to intramuscular IFNB-1a injected once/week with the Avonex®Pen™ device improves treatment tolerability and quality of life in stable MS patients.

METHODS

Clinically stable MS patients, whom their treating neurologist switched from high frequency injectable DMTs to weekly intramuscular IFNB-1a because of bothersome injection site reactions, were included. Injection site and systemic tolerability were measured by a composite 100 mm visual analogue scale at screening, months 4 and 12. Treatment satisfaction, quality of life, relapses and EDSS progression were also recorded. The primary endpoint was change in injection site tolerability from screening to Month 4. Descriptive statistics and Wilcoxon paired signed-rank tests were applied.

RESULTS

The median injection site tolerability and systemic tolerability were significantly improved at months 4 (n = 36) and 12 (n = 33) [change -51.60 (IQR: -60.13, -39.60) mm (p < 0.0001); -26.00 (-54.00, 2.25) mm (p = 0.002)]. Median treatment satisfaction was significantly improved at month 12 [change of 18.00 (2.00, 47.50) mm (p = 0.0003)]. Physical and mental components of the SF-36 did not change significantly, and 30/33 (90.9%) and 33/33 (100%) patients were free from relapses and EDSS progression at month 12.

CONCLUSIONS

Weekly intramuscular IFNB-1a may represent an alternative treatment option for clinically stable MS patients suffering from intolerable injection-related side effects under treatment with high frequency injectable DMTs.

Immune response to vaccines is maintained in patients treated with dimethyl fumarate

Objectives:

To investigate the immune response to vaccinations in patients with relapsing forms of MS treated with delayed-release dimethyl fumarate (DMF) vs nonpegylated interferon (IFN).

Methods:

In this open-label, multicenter study, patients received 3 vaccinations: (1) tetanus-diphtheria toxoid (Td) to test T-cell–dependent recall response, (2) pneumococcal vaccine polyvalent to test T-cell–independent humoral response, and (3) meningococcal (groups A, C, W-135, and Y) oligosaccharide CRM₁₉₇ conjugate to test T-cell–dependent neoantigen response. Eligible patients were aged 18–55 years, diagnosed with relapsing-remitting MS (RRMS), and either treated for ≥6 months with an approved dose of DMF or for ≥3 months with an approved dose of nonpegylated IFN. Primary end point was the proportion of patients with ≥2-fold rise in antitetanus serum IgG levels from prevaccination to 4 weeks after vaccination.

Results:

Seventy-one patients (DMF treated, 38; IFN treated, 33) were enrolled. The mean age was 45.3 years (range 27–55); 86% were women. Responder rates (≥2-fold rise) to Td vaccination were comparable between DMF- and IFN-treated groups (68% vs 73%). Responder rates (≥2-fold rise) were also similar between DMF- and IFN-treated groups for diphtheria antitoxoid (58% vs 61%), pneumococcal serotype 3 (66% vs 79%), pneumococcal serotype 8 (95% vs 88%), and meningococcal serogroup C (53% vs 53%), all p > 0.05. In a post hoc analysis, no meaningful differences were observed between groups in the proportion of responders when stratified by age category or lymphocyte count.

Conclusions:

DMF-treated patients mount an immune response to recall, neoantigens, and T-cell–independent antigens, which was comparable with that of IFN-treated patients and provided adequate seroprotection.

ClinicalTrials.gov identifier:

NCT02097849.

Classification of evidence:

This study provides Class II evidence that patients with RRMS treated with DMF respond to vaccinations comparably with IFN-treated patients.

Neutralizing antibodies in MS therapy: reviewing the Rebif experience

Treatment of relapsing-remitting multiple sclerosis (RRMS) with protein therapeutics such as interferon beta (IFNβ) frequently results in the development of binding antibodies (BAbs) to the administered agent. Neutralizing antibodies (NAbs) are a subset of BAbs characterized by their interference with IFNβ's biological target(s) and/or function(s). At the treatment group level, NAbs to IFNβ have been shown to have an impact on relapse rate and MRI disease measures. However, in individual patients, the clinical significance of NAbs remains controversial because of the lack of standardized assessment procedures, the absence of widely accepted cutoff values to distinguish NAb-positive from NAb-negative patients, and the high rate of seroconversion (to NAb-negative status) observed in clinical studies. At the recommended 44 μg tiw dose of IFNβ-1a subcutaneous (SC) (Rebif®), 12—14% of patients were persistently NAb-positive at two, three, and four years of treatment, while ~25% of anytime NAb-positive patients later became seronegative. Relapse rate and MRI measures of disease were higher in NAb-positive than NAb-negative patients; however, both demonstrated significant improvement versus placebo treatment or delayed treatment patients. Pending improved assessment methodology and better characterization of the clinical impact of NAbs, treatment decisions should continue to be based on the wide range of factors that determine clinical effectiveness. Multiple Sclerosis 2007; 13: S8—S13 http://msj.sagepub.com

Early MRI results and odds of attaining 'no evidence of disease activity' status in MS patients treated with interferon β-1a in the EVIDENCE study

INTRODUCTION

'No evidence of disease activity' (NEDA) is increasingly used as a treatment target with disease-modifying drugs for relapsing multiple sclerosis.

METHODS

This post-hoc analysis of the randomised EVIDENCE trial compared interferon beta-1a injected subcutaneously three times weekly (IFN β-1a SC tiw) with interferon β-1a injected intramuscularly once weekly (IFN β-1a IM qw) on NEDA and clinical activity-free (CAF) status. The influence of the frequency of magnetic resonance imaging (MRI) scanning on NEDA and the effect of baseline T1 gadolinium-enhancing (Gd+) lesions on NEDA and CAF were also investigated.

RESULTS

More patients in the IFN β-1a SC tiw group achieved NEDA compared with the IFN β-1a IM qw group, although rates were lower when monthly MRI scans through 24weeks were included (35.0% vs. 21.6%, respectively; p<0.001) versus the 24-week scan alone (59.5% vs. 41.2%; p<0.001). Absence of baseline Gd+ lesions predicted NEDA through Week 72 in the IFN β-1a IM qw group (p=0.022), and CAF through Week 48 in patients receiving IFN β-1a SC tiw (p=0.024).

CONCLUSIONS

IFN β-1a SC tiw was associated with significantly higher rate of NEDA status compared with IFN β-1a IM qw. Baseline Gd+ lesions augured less frequent CAF or NEDA status. Inclusion of more MRI scans in the analysis reduced rates of NEDA status.

Comparison for Efficacy and Tolerability among Ten Drugs for Treatment of Parkinson's Disease: A Network Meta-Analysis

Parkinson's disease (PD) is a long term disorder affects the central nervous system and we aim to determine the relative efficacy of the current available drugs used in PD. Firstly, we performed a systematic review in current literature and eligible studies were retrieved from online databases, relevant data were extracted. Efficacy of these medications was assessed by different Unified Parkinson's Disease Rating Scales (UPDRS). Mean difference (MD) and odds ratio (OR) were produced by pairwise or network meta-analysis (NMA). Finally, we performed a cluster analysis for the included medications with respect to their surface under the cumulative ranking curve (SUCRA). Pairwise meta-analysis suggests that selegiline had a higher ranking in UPDRS II, UPDRS III and UPDRS total than bromocriptine and levodopa. Selegiline was more tolerable than bromocriptine (OR = 0.62, CI: 0.39 to 0.98) and pramipexole was less tolerable than levodopa (OR = 1.43, CI = 1.00 to 2.04). Results of NMA indicate that patients with levodopa, pramipexole, ropinirole and selegiline exhibited a significantly improved UPDRS III than those with lazabemide. To sum up, levodopa, selegiline, ropinirole and rotigotine were recommended for PD patients as they appeared relatively high efficacy and tolerability.

B Cells Are Multifunctional Players in Multiple Sclerosis Pathogenesis: Insights from Therapeutic Interventions

Multiple sclerosis (MS) is a severe disease of the central nervous system (CNS) characterized by autoimmune inflammation and neurodegeneration. Historically, damage to the CNS was thought to be mediated predominantly by activated pro-inflammatory T cells. B cell involvement in the pathogenesis of MS was solely attributed to autoantibody production. The first clues for the involvement of antibody-independent B cell functions in MS pathology came from positive results in clinical trials of the B cell-depleting treatment rituximab in patients with relapsing-remitting (RR) MS. The survival of antibody-secreting plasma cells and decrease in T cell numbers indicated the importance of other B cell functions in MS such as antigen presentation, costimulation, and cytokine production. Rituximab provided us with an example of how clinical trials can lead to new research opportunities concerning B cell biology. Moreover, analysis of the antibody-independent B cell functions in MS has gained interest since these trials. Limited information is present on the effects of current immunomodulatory therapies on B cell functions, although effects of both first-line (interferon, glatiramer acetate, dimethyl fumarate, and teriflunomide), second-line (fingolimod, natalizumab), and even third-line (monoclonal antibody therapies) treatments on B cell subtype distribution, expression of functional surface markers, and secretion of different cytokines by B cells have been studied to some extent. In this review, we summarize the effects of different MS-related treatments on B cell functions that have been described up to now in order to find new research opportunities and contribute to the understanding of the pathogenesis of MS.

Efficacy and safety of subcutaneous interferon-β-1a in patients with a first demyelinating event and early multiple sclerosis

Introduction: Multiple sclerosis (MS) is an inflammatory demyelinating disease of the CNS. Evidence suggests that MS should be treated as early as possible in order to maximize the benefit of treatment.

Areas covered: This review details current understanding about the treatment of relapsing–remitting MS (RRMS). The pharmacological and clinical data on the use of subcutaneous (s.c.) interferon β-1a (IFN-β-1a) as a therapeutic option for RRMS are covered, with a focus on the importance of treating patients with MS as early as possible in the course of the disease, in order to delay permanent axonal damage that is responsible for the signs and symptoms of disease progression.

Expert opinion: There is a wealth of data on the treatment of RRMS with s.c. IFN-β-1a indicating that patients treated during the early inflammatory stages of the disease have significantly improved short-term outcomes compared with patients who commence treatment late. It remains to be determined whether the short-term effects of early treatment will translate into long-lasting benefits, although it is hoped that ongoing research will help to answer this question.

Short peptide type I interferon mimetics: therapeutics for experimental allergic encephalomyelitis, melanoma, and viral infections

The classical canonical model of interferon (IFN) signaling focuses solely on the activation of STAT transcription factors, which limits the model in terms of specific gene activation, associated epigenetic events, and IFN mimetic development. Accordingly, we have developed a noncanonical model of IFN signaling and report the development of short type I IFN peptide mimetic peptides based on the model. The mimetics, human IFNα1(152-189), human IFNβ(150-187), and ovine IFNτ(156-195) are derived from the C-terminus of the parent IFNs and function intracellularly based on the noncanonical model. Vaccinia virus produces a decoy IFN receptor (B18R) that inhibits type I IFN, but the IFN mimetics bypass B18R for effective antiviral activity. By contrast, both parent IFNs and mimetics inhibited vesicular stomatitis virus. The mimetics also possessed anti-tumor activity against murine melanoma B16 tumor cells in culture and in mice, including synergizing with suppressor of cytokine signaling 1 antagonist. Finally, the mimetics were potent therapeutics against experimental allergic encephalomyelitis, a mouse model of multiple sclerosis. The mimetics lack toxic side effects of the parent IFNs and, thus, are a potent therapeutic replacement of IFNs as therapeutics.

Disease-modifying agents in multiple sclerosis

Over the past two decades, major advances have been made in the development of disease-modifying agents (DMAs) for multiple sclerosis (MS), and nine agents are now licensed for use in the treatment of MS in the United States. Clinical trials have demonstrated that a number of investigational agents have beneficial effects on clinical and radiographic measures of disease activity, thus the repertoire of available DMAs in MS will likely continue to expand moving forward. Although many of the first-line DMAs have the benefits of established long-term safety and tolerability, in some patients, treatment with one of the more potent novel agents may be appropriate. However, the use of novel agents must be approached with caution, since short-term clinical trials give little information on the long-term efficacy and safety of novel DMAs in MS patients. This chapter will consider the efficacy and safety of both established and investigational agents for the treatment of MS.

The role of a non-canonical JAK-STAT pathway in IFN therapy of poxvirus infection and multiple sclerosis: An example of Occam's Broom?

Signaling by cytokines such as the interferons (IFNs) involves Janus kinases (JAKs) and signal transducer and activator of transcription (STAT) transcription factors. The beauty of the classical model of JAK-STAT signaling is its simplicity in that JAK-activated STATs in the nucleus are responsible for specific gene activation. The fact that many ligands, growth factors, and hormones use the same STAT transcription factors, but exert different functions at the level of the cell, tissue, and organ would suggest significant shortcomings in the classical model. Our studies have resulted in the development of a non-canonical, more complex model of IFN signaling that bears a striking resemblance to that of steroid hormone (SH)/steroid receptor (SR) signaling. Thus, both types I and II IFN signaling involves nuclear translocation of complexed ligand, receptor, activated JAKs, and activated STATs to the promoters of the genes that are specifically activated by the IFNs, where they are involved in specific gene activation and epigenetic remodeling. Receptor intracellular domains play an important role in binding the C-terminus of the IFNs, which is the basis for our development of IFN mimetics. The IFN mimetics are not recognized by poxvirus decoy receptors, since the decoy receptors compete for extracellular binding and not intracellular binding. Further, the type I IFN mimetics provide therapeutic protection against experimental allergic encephalomyelitis (EAE), a model of multiple sclerosis, without the side effects. Extracellular receptor binding by intact IFN is the primary reason for undesirable side effects of flu-like symptoms, bone-marrow suppression, and weight loss. The non-canonical model of IFN signaling thus provides insight into the specificity of such signaling and a mechanism for development of IFN mimetics. It is our contention that this model applies to other cytokines.

IFN signaling: how a non-canonical model led to the development of IFN mimetics

The classical model of cytokine signaling dominates our view of specific gene activation by cytokines such as the interferons (IFNs). The importance of the model extends beyond cytokines and applies to hormones such as growth hormone (GH) and insulin, and growth factors such as epidermal growth factor (EGF) and fibroblast growth factor (FGF). According to this model, ligand activates the cell via interaction with the extracellular domain of the receptor. This results in activation of receptor or receptor-associated tyrosine kinases, primarily of the Janus activated kinase (JAK) family, phosphorylation and dimerization of the signal transducer and activator of transcription (STAT) transcription factors, which dissociate from the receptor cytoplasmic domain and translocate to the nucleus. This view ascribes no further role to the ligand, JAK kinase, or receptor in either specific gene activation or the associated epigenetic events. The presence of dimeric STATs in the nucleus essentially explains it all. Our studies have resulted in the development of a non-canonical, more complex model of IFNγ signaling that is akin to that of steroid hormone (SH)/steroid receptor (SR) signaling. We have shown that ligand, receptor, activated JAKs, and STATs are associated with specific gene activation, where the receptor subunit IFNGR1 functions as a co-transcription factor and the JAKs are involved in associated epigenetic events. We found that the type I IFN system functions similarly. The fact that GH receptor, insulin receptor, EGF receptor, and FGF receptor undergo nuclear translocation upon ligand binding suggests that they may also function similarly. The SH/SR nature of type I and II IFN signaling provides insight into the specificity of signaling by members of cytokine families. The non-canonical model could also provide better understanding to more complex cytokine families such as those of IL-2 and IL-12, whose members often use the same JAKs and STATs, but also have different functions and properties.

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

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

Type I IFN receptor controls activated TYK2 in the nucleus: implications for EAE therapy

Recent studies have suggested that activated wild-type and mutant Janus kinase JAK2 play a role in the epigenetics of histone modification, where it phosphorylates histone H3 on tyrosine 41(H3pY41). We showed that type I IFN signaling involves activated TYK2 in the nucleus. ChIP-PCR demonstrated the presence of receptor subunits IFNAR1 and IFNAR2 along with TYK2, STAT1, and H3pY41 specifically at the promoter of the OAS1 gene in IFN treated cells. A complex of IFNAR1, TYK2, and STAT1α was also shown in the nucleus by immunoprecipitation. IFN treatment was required for TYK2 activation in the nucleus. The presence of IFNAR1, IFNAR2, and activated STAT1 and STAT2, as well as the type I IFN in the nucleus of treated cells was confirmed by the combination of Western blotting and confocal microscopy. Trimethylated histone H3 lysine 9 underwent demethylation and subsequent acetylation specifically in the region of the OAS1 promoter. Resultant N-terminal truncated IFN mimetics functioned intracellularly as antivirals as well as therapeutics against experimental allergic encephalomyelitis without the undesirable side effects that limit the therapeutic efficacy of IFNβ in treatment of multiple sclerosis. The findings indicate that IFN signaling is complex like that of steroid signaling.

Interferon beta and glatiramer acetate therapy

Interferon beta and glatiramer acetate have been mainstays of treatment in relapsingremitting multiple sclerosis for two decades. Remarkable advances in our understanding of immune function and dysfunction as well as increasingly sophisticated clinical trial design have stemmed from efforts to better understand these drugs. In this chapter, we review the history of their development and elaborate on known and theorized mechanisms of action. We describe the pivotal clinical trials that have led to their widespread use. We evaluate the clinical use of the drugs including tolerability, side effects, and efficacy measures. Finally, we look to the future of interferon beta and glatiramer acetate in the context of an ever growing armamentarium of treatments for relapsing remitting multiple sclerosis.

Subcutaneous IFN-β1a to treat relapsing-remitting multiple sclerosis

Multiple sclerosis (MS) is the main nontraumatic cause of handicap in young adults. Immunomodulators and treatments limiting lymphocyte migration have been proven efficient to treat relapsing-remitting MS. Subcutaneous IFN-β1a improve relapse rate and MRI parameters in a series of double-blind, placebo-controlled trials in relapsing-remitting MS patients. Similar results, and with a greater extent, were obtained when treating patients with a first demyelinating event suggestive of MS. Except for the rare liver toxicity, the drug is well tolerated and has no severe adverse reaction. When compared with intramuscular IFN-β1a, both relapse rate and MRI parameters were modulated in favor of the subcutaneous administration. Although the effect of subcutaneous IFN-β1a on disability progression is limited, the good tolerance profile together with the efficiency of the drug explain why this treatment, as well as the other interferons and glatiramer acetate, is a first-line therapy for relapsing-remitting MS.

Patient adherence to and tolerability of self-administered interferon β-1a using an electronic autoinjection device: a multicentre, open-label, phase IV study

Background

Achieving good adherence to self-injected treatments for multiple sclerosis can be difficult. Injection devices may help to overcome some of the injection-related barriers to adherence that can be experienced by patients. We sought to assess short-term adherence to, and tolerability of, interferon (IFN) β-1a administered via electronic autoinjection device in patients with relapsing-remitting multiple sclerosis (RRMS).

Methods

BRIDGE (RebiSmart to self-inject Rebif serum-free formulation in a multidose cartridge) was a 12-week, multicentre, open-label, single-arm, observational, Phase IV study in which patients self-administered IFN β-1a (titrated to 44 μg), subcutaneously (sc), three times weekly, via electronic autoinjection device. Patients were assessed at baseline and 4-weekly intervals to Week 12 or early termination (ET) for: physical examinations; diary card completion (baseline, Weeks 4, 8 only); neurological examinations (baseline, Week 12/ET only); MS Treatment Concern Questionnaire (MSTCQ; Weeks 4, 8, 12 only); Convenience Questionnaire (Week 12 only); Hospital Anxiety and Depression Scale (HADS); and Paced Auditory Serial Addition Task (PASAT; baseline only). Adherence was defined as administration of ≥ 80% of scheduled injections, recorded by the autoinjection device.

Results

Overall, 88.2% (105/119; intent-to-treat population) of patients were adherent; 67.2% (80/119) administered all scheduled injections. Medical reasons accounted for 35.6% (31/87) of missed injections, forgetfulness for 20.6% (18/87). Adherence did not correlate with baseline Expanded Disability Status Scale (P = 0.821) or PASAT (P = 0.952) scores, or pre-study therapy (P = 0.303). No significant changes (baseline-Week 12) in mean HADS depression (P = 0.482) or anxiety (P = 0.156) scores were observed. 'Overall convenience' was the most important reported benefit of the autoinjection device. Device features associated with handling and ease of use were highly rated. Mean MSTCQ scores for 'flu-like' symptoms (P = 0.022) and global side effects (P = 0.002) significantly improved from Week 4-12. Mean MSTCQ scores for pain at injection site and injection pain increased from Week 4-12 (P < 0.001). Adverse events were mild/moderate. No new safety signals were identified.

Conclusion

Convenience and ease of use of the autoinjection device may improve adherence and, therefore, outcomes, in patients with RRMS receiving sc IFN β-1a.

Trial registration

EU Clinical Trials Register (EU-CTR; http://www.clinicaltrialsregister.eu): 2009-013333-24

Cutaneous adverse events associated with disease-modifying treatment in multiple sclerosis: a systematic review

Glatiramer acetate and interferon-beta are approved first-line disease-modifying treatments (DMTs) for multiple sclerosis (MS). DMTs can be associated with cutaneous adverse events, which may influence treatment adherence and patient quality of life. In this systematic review, we aimed to provide an overview of the clinical spectrum and the incidence of skin reactions associated with DMTs. A systematic literature search was performed up to May 2011 in Medline, Embase, and Cochrane databases without applying restrictions in study design, language, or publishing date. Eligible for inclusion were articles describing any skin reaction related to DMTs in MS patients. Selection of articles and data extraction were performed by two authors independently. One hundred and six articles were included, of which 41 (39%) were randomized controlled trials or cohort studies reporting incidences of mainly local injection-site reactions. A large number of patients had experienced some form of localized injection-site reaction: up to 90% for those using subcutaneous formulations and up to 33% for those using an intramuscular formulation. Sixty-five case-reports involving 106 MS patients described a wide spectrum of cutaneous adverse events, the most frequently reported being lipoatrophy, cutaneous necrosis and ulcers, and various immune-mediated inflammatory skin diseases. DMTs for MS are frequently associated with local injection-site reactions and a wide spectrum of generalized cutaneous adverse events, in particular, the subcutaneous formulations. Although some of the skin reactions may be severe and persistent, most of them are mild and do not require cessation of DMT.

Subcutaneous recombinant interferon-β-1a (Rebif®): a review of its use in the treatment of relapsing multiple sclerosis

Subcutaneous recombinant interferon-β-1a (SC IFNβ-1a) [Rebif®] is indicated as monotherapy for the prevention of relapses and progression of physical disability in patients with relapsing multiple sclerosis (MS). This article reviews the efficacy and tolerability of SC IFNβ-1a in this indication, with further discussion of its pharmacological properties and pertinent pharmacoeconomic studies. SC IFNβ-1a efficacy and tolerability were evaluated in randomized, double-blind, multinational trials in patients with relapsing-remitting MS (RRMS). Its efficacy was demonstrated in the 2-year PRISMS trial, as SC IFNβ-1a 22 or 44 μg three times weekly (tiw) significantly reduced relapse rates, with an ≈30% relative risk reduction compared with placebo. SC IFNβ-1a was also associated with significantly delayed progression of disability, and lower disease activity according to MRI, relative to placebo. In the 24-week EVIDENCE trial, a significantly higher proportion of SC IFNβ-1a 44 μg tiw than intramuscular IFNβ-1a (Avonex®) 30 μg once weekly recipients remained relapse free. A serum-free formulation of SC IFNβ-1a 44 μg tiw was more efficacious than placebo in preventing the development of brain lesions in the 16-week IMPROVE trial. In the 96-week REGARD trial, the efficacy of SC IFNβ-1a 44 μg tiw was not significantly different to that of glatiramer acetate for clinical endpoints, although it was associated with reduced development of brain lesions compared with glatiramer acetate, according to some MRI endpoints. In the 36-month CAMMS223 trial, alemtuzumab led to significantly lower relapse rates and risk of developing sustained disability than SC IFNβ-1a 44 μg tiw, and was generally more efficacious according to other clinical and MRI endpoints. Across trials, influenza-like symptoms, injection-site reactions, haematological disturbances and hepatic enzyme abnormalities were the most common treatment-emergent adverse events occurring with SC IFNβ-1a. In the PRISMS trial, SC IFNβ-1a 22 and 44 μg tiw recipients had more injection-site reactions than placebo recipients and, at the higher dosage, haematological disturbances and increases in ALT levels were also significantly more frequent than with placebo. Pooled data from clinical trials and postmarketing surveillance indicate that haematological and hepatic adverse events are generally asymptomatic and rarely result in treatment discontinuation. Nevertheless, some cases of serious hepatic complications have been reported. In cost-utility studies, first-line therapies for RRMS, including SC IFNβ-1a, all exceeded commonly accepted US thresholds for incremental cost per quality-adjusted life-years gained relative to symptomatic treatment. However, because of patient need and the difficulty in adequately assessing cost utility in a gradually progressive disease, these agents have been made available to many patients worldwide through special access programmes. Overall, SC IFNβ-1a has a favourable risk-benefit ratio and is a valuable first-line treatment option for patients with relapsing MS.

Natalizumab for relapsing remitting multiple sclerosis

BACKGROUND

Natalizumab (NTZ) (Tysabri(®)) is a monoclonal antibody that inhibits leukocyte migration across the blood-brain barrier, thus reducing inflammation in central nervous system, and has been approved worldwide for the treatment of relapsing-remitting multiple sclerosis (RRMS).

OBJECTIVES

To evaluate the efficacy, tolerability and safety of NTZ in the treatment of patients with RRMS.

SEARCH STRATEGY

We searched the Cochrane Multiple Sclerosis Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, 2010, Issue 1), MEDLINE (PubMed) and EMBASE, all up to 19 February 2010, and bibliographies of papers. Handsearching was carried out. Trialists and pharmaceutical companies were contacted. Furthermore, the websites of US Food and Drug Administration (FDA), the European Medicines Evaluation Agency (EMA) and the National Institute for health and Clinical Excellence (NICE) were also checked.

SELECTION CRITERIA

All double-blind, randomised, controlled trials analysing more than a single infusion of NTZ (dosage > 3 mg/kg intravenous infusion every 4 weeks), also including its use as add-on treatment, versus placebo or other drugs in patients with RRMS. No restrictions on the basis of duration of treatment or length of follow up.

DATA COLLECTION AND ANALYSIS

Three reviewers independently selected articles which met the inclusion criteria. Disagreements were solved by discussion. Two reviewers independently extracted the data and assessed the methodological quality of each trial. Missing data was sought by contacting principal authors and Biogen Idec, through Biogen-Dompé Italia.

MAIN RESULTS

Three studies met the inclusion criteria. These included one placebo-controlled trial (942 patients) and two add-on placebo-controlled trials, i.e. one plus glatiramer acetate (110 patients) and the second plus interferon beta-1a (1171 patients).This review assessed the efficacy, tolerability and safety of NTZ in patients with RRMS. Data was conclusive with respect to efficacy and tolerability, but not safety. As far as efficacy is concerned, the results showed statistically significant evidence in favour of NTZ for all the primary outcomes and for the secondary ones where data was available. NTZ reduced the risk of experiencing at least one new exacerbation at 2 years by about 40% and of experiencing progression at 2 years by about 25% as compared to a control group. MRI parameters showed statistical evidence in favour of participants receiving NTZ. Infusion reactions, anxiety, sinus congestion, lower limb swelling, rigors, vaginitis and menstrual disorders were reported as adverse events (AEs) more frequently after NTZ treatment. In this review NTZ was found to be well tolerated over a follow-up period of two years: the number of patients experiencing at least one AE (including severe and serious AEs) during this period did not differ between NTZ-treated patients and controls. Safety concerns have been raised about Progressive Multifocal Leukoencephalopathy (PML). In the trials included in this review, two cases of PML were encountered: one in a patient who had received 29 doses of NTZ and a second fatal case of PML in another patient after 37 doses of NTZ. Our protocol was insufficient to evaluate PML risk as well as other rare and long-term adverse events such as cancers and other opportunistic infections, which are very important issues in considering the risk/benefit ratio of NTZ.

AUTHORS' CONCLUSIONS

Although one trial did not contribute to efficacy results due to its duration, we found robust evidence in favour of a reduction in relapses and disability at 2 years in RRMS patients treated with NTZ. The drug was well tolerated. There are current significant safety concerns due to reporting of an increasing number of PML cases in patients treated with NTZ. This review was unable to provide an up-to-date systematic assessment of the risk due to the maximum 2 year-duration of the trials included. An independent systematic review of the safety profile of NTZ is warranted. NTZ should be used only by skilled neurologists in MS centres under surveillance programs.All the data in this review came from trials supported by the Pharmaceutical Industry. In agreement with the Cochrane Collaboration policy, this may be considered a potential source of bias.

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

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

Escalation to natalizumab or switching among immunomodulators in relapsing multiple sclerosis

OBJECTIVE

To evaluate whether an escalation approach was more effective in suppressing clinical and magnetic resonance imaging (MRI) activity than switching among immunomodulators in relapsing-remitting multiple sclerosis (RRMS) patients.

METHODS

In this post-marketing, prospective, observational study in two Italian multiple sclerosis (MS) centres, a total of 285 RRMS patients who failed a first-line treatment with interferon beta (IFNβ) or glatiramer acetate (GA) were considered. Patients were subdivided according to the strategy adopted after the failure (defined as the occurrence of ≥2 relapses or 1 relapse with residual disability): the switching (SWI) group, i.e. those switched among different IFNβ formulations, or from IFNβ to GA and vice versa; and the escalating (ESC) group, i.e. those escalated to natalizumab. Proportions of patients free from different types of disease activity (relapses, sustained disability progression, new active lesions on MRI, or a combination of them) were calculated at 12 and 24 months. Since patients were not randomized to treatment group, propensity score (PS)-adjusted Cox regression models were built to control for several potential confounders.

RESULTS

At 12 months there were no differences between the two groups in proportions of patients free from relapse, disability progression, MRI activity, and combined activity. After 24 months we observed greater proportions of patients in the ESC than SWI group free from relapse (p < 0.0001), disability progression (p = 0.0045), MRI activity (p = 0.0003), and combined activity (p < 0.0001). PS-adjusted models confirmed these findings, with hazard ratios ranging from 0.38 to 0.56 favours the ESC group.

CONCLUSION

We suggest that an escalation to natalizumab is more effective than switching among immunomodulators in RRMS patients who failed a first-line treatment.

Interferon β-1b directly modulates human neural stem/progenitor cell fate

Interferon beta (IFN-β) is a mainline treatment for multiple sclerosis (MS); however its exact mechanism of action is not completely understood. IFN-β is known as an immunomodulator; although recent evidence suggests that IFN-β may also act directly on neural stem/progenitor cells (NPCs) in the central nervous system (CNS). NPCs can differentiate into all neural lineage cells, which could contribute to the remyelination and repair of MS lesions. Understanding how IFN-β influences NPC physiology is critical to develop more specific therapies that can better assist this repair process. In this study, we investigated the effects of IFN β-1b (Betaseron®) on human NPCs in vitro (hNPCs). Our data demonstrate a dose-dependent response of hNPCs to IFN β-1b treatment via sustained proliferation and differentiation. Furthermore, we offer insight into the signaling pathways involved in these mechanisms. Overall, this study shows a direct effect of IFN β-1b on hNPCs and highlights the need to further understand how current MS treatments can modulate endogenous NPC populations within the CNS.

Demographic, genetic, and environmental factors that modify disease course

As with susceptibility to disease, it is likely that multiple factors interact to influence the phenotype of multiple sclerosis and long-term disease outcomes. Such factors may include genetic factors, socioeconomic status, comorbid diseases, and health behaviors, as well as environmental exposures. An improved understanding of the influence of these factors on disease course may reap several benefits, such as improved prognostication, allowing us to tailor disease management with respect to intensity of disease-modifying therapies and changes in specific health behaviors, in the broad context of coexisting health issues. Such information can facilitate appropriately adjusted comparisons within and between populations. Elucidation of these factors will require careful study of well-characterized populations in which the roles of multiple factors are considered simultaneously.

Disease-modifying agents in multiple sclerosis

Since 1993, six disease-modifying therapies for multiple sclerosis (MS) have been proven to be of benefit in rigorous phase III clinical trials. Other agents are also available and are used to treat MS, but definitive data on their efficacy is lacking. Currently, disease-modifying therapy is used for relapsing forms of MS. This includes clinically isolated syndrome/first-attack high-risk patients, relapsing patients, secondary progressive patients who are still experiencing relapses, and progressive relapsing patients. The choice of agent depends upon drug factors (including affordability, availability, convenience, efficacy, and side effects), disease factors (including clinical and neuroimaging prognostic indicators), and patient factors (including comorbidities, lifestyle, and personal preference). This review will discuss the disease-modifying agents used currently in MS, as well as available alternative agents.

Impact of exposure to interferon beta-1a on outcomes in patients with relapsing-remitting multiple sclerosis: exploratory analyses from the PRISMS long-term follow-up study

OBJECTIVE

To explore the effects of exposure to subcutaneous (sc) interferon (IFN) beta-1a on efficacy in patients with relapsing-remitting multiple sclerosis (RRMS) enrolled in the PRISMS (Prevention of Relapses and disability by Interferon beta-1a Subcutaneously in Multiple Sclerosis) study.

METHODS

Patients with RRMS received IFN beta-1a, 44 or 22 µg sc three times weekly (tiw), or placebo, for 2 years, at which point placebo recipients were re-randomized to IFN beta-1a, 44 or 22 µg sc tiw, for a further 2-4 years. Long-term follow-up visits occurred 7-8 years after enrolment and allowed participation of patients who had previously discontinued treatment. Post hoc descriptive analyses were conducted within the lower (MIN) and upper (MAX) quartiles of patients divided according to cumulative dose of IFN beta-1a and cumulative time on treatment. Outcomes were explored in patients initially randomized to IFN beta-1a, 44 µg sc tiw, who had received continuous or noncontinuous therapy during the study.

RESULTS

For both cumulative dose and time analyses, the MIN and MAX groups comprised 96 and 95 patients, respectively. The continuous and noncontinuous groups included 45 and 91 patients, respectively. The MAX DOSE and MAX TIME groups had lower annualized relapse rates, lower rates of conversion to secondary progressive MS, lower percentages of patients with Expanded Disability Status Scale progression, higher percentages of relapse-free patients, and less T2 burden of disease than the MIN groups. The continuous therapy group had a lower annualized relapse rate and lower percentages of patients with Expanded Disability Status Scale progression or conversion to secondary progressive MS than the noncontinuous therapy group.

CONCLUSIONS

The findings of these post hoc analyses suggest that high exposure to sc IFN beta-1a may be associated with better clinical outcomes than low exposure, and also highlight the importance of maximizing adherence. Additional prospective investigation is warranted to evaluate further the effects of treatment exposure on outcomes and to determine the benefits of interventions to improve adherence.

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.

[Interferon β for multiple sclerosis. How much is good enough?]

Interferon β-1b (IFNB-1b, Betaferon®) was the first therapy for multiple sclerosis (MS) showing efficacy in a randomized controlled clinical trial. Early studies suggested a dose-dependency of the clinical efficacy of IFNB-1b. However, until recently no reliable clinical data were available to assess the potential of higher dosing to increase therapeutic efficacy. In addition, no clinical trials have been conducted to directly compare the efficacy of IFNB-1b with that of glatiramer acetate, an alternative first line treatment option for relapsing-remitting MS. Just recently, the prospective, randomized, multicenter study BEYOND was published which addressed both issues. In this review the BEYOND trial is reviewed and placed in the context of advantages and disadvantages of currently available first line therapies for MS.

Clinical effects and tolerability of high-dose, high-frequency recombinant interferon beta-1a in patients with multiple sclerosis: maximizing therapy through long-term adherence

IMPORTANCE OF THE FIELD

High-dose, high-frequency IFN beta-1a in multiple sclerosis (MS) can prevent lesion formation, decrease the frequency/severity of relapses and delay progression of disability, with a proven safety profile. Rates of non-adherence are high. There are drugs under investigation that may have greater efficacy and different safety profiles from existing therapies.

AREAS COVERED IN THIS REVIEW

Evidence supporting the efficacy of IFN beta-1a, factors contributing to non-adherence, and strategies to combat non-adherence. It is hoped that these strategies, coupled with future advances in pharmacogenetics, might lead to better outcomes. The PubMed database was searched using the terms "multiple sclerosis" and "interferon beta-1a", for papers published between 1998 and 2010. Relevant manuscripts and pivotal papers from clinical trials were cited. Searches of abstracts from congresses were also performed to obtain recent findings.

WHAT THE READER WILL GAIN

An overview of early pivotal trials, comparative studies with other treatments, and recent studies assessing the development of this therapy.

TAKE HOME MESSAGE

Long-term treatment with IFN beta-1a has benefits in MS and a good safety profile. Although adherence outside of clinical trials can be poor, injection devices, better tolerated drug formulations and education regarding treatment expectations are some of the strategies employed to help patients to adhere to treatment in the hope of improving outcomes.

Identification of targets and new developments in the treatment of multiple sclerosis--focus on cladribine

Orally available disease-modifying drugs for relapsing-remitting multiple sclerosis (MS) represent an unmet need for this chronic and debilitating disease. Among 5 currently investigated drugs at phase 3 clinical stage, promising efficacy data for fingolimod and oral cladribine have recently been published. However, benefits need to be weighed against the risks to define the role of these compounds within current treatment regimens. In this review, data on the efficacy of a promising compound, oral cladribine, are discussed and balanced with known and anticipated risks in a postmarketing era, and finally gives an outlook on the potential place of this drug in treatment algorithms for MS in the future.

Disease modifying agents for multiple sclerosis

Objective:

To summarize major clinical trials which evaluate the efficacy and safety data of approved disease modifying agents for the treatment of various types of multiple sclerosis.

Data Sources:

A MEDLINE (1966 to August 2008) search of clinical trials using the terms multiple sclerosis, interferon, glatiramer, mitoxantrone and natalizumab was performed. A manual bibliographic search was also conducted. English-language articles identified from the searches were evaluated. New agents under investigation in phase 3 clinical trials were identified using www.clinicaltrials.gov.

Study Selection & Data Extraction:

Relevant information was identified and selected based on clinical relevance and evidence-based strength. Prescribing information leaflets were used to provide usual dosage, contraindications, precautions, monitoring parameters and other relevant drug-specific information.

Data Synthesis:

Interferon beta products are more efficacious for the treatment of relapsing-remitting multiple sclerosis. Interferon beta 1-b also delayed the time to diagnosis of definite multiple sclerosis and reduced brain lesion burden in patients with clinical isolated syndrome. Glatiramer and natalizumab have both established efficacy in relapsing forms of multiple sclerosis; whereas mitoxantrone is more commonly used in patients with advanced disease. There are limited data the comparative efficacy among different disease modifying agents. New agents currently under investigation have showed promising results and may offer more treatment options in the future.

Conclusions:

MS is a complex and devastating disease with challenging treatment considerations and approaches. Interferon beta products continue to be the mainstay of therapy in many patients, however, other treatments are proving to be at least as effective in the management of various types of MS. Newer compounds are being developed and studied with much anticipation and promise for the clinical management of the disease.

PRISMS: the story of a pivotal clinical trial series in multiple sclerosis

BACKGROUND

The PRISMS (Prevention of Relapses and disability by Interferon beta-1a Subcutaneously in Multiple Sclerosis) study was initiated in 1994, at which time there were few disease-modifying drugs for multiple sclerosis (MS). The PRISMS series of studies has since provided up to 8 years of clinical, magnetic resonance imaging (MRI), safety, and immunogenicity data on the use of subcutaneous (sc) interferon (IFN) beta-1a in patients with relapsing-remitting MS. This review is the first collation of all these data in one article, with a look ahead to the next generation of studies involving the new formulation of sc IFN beta-1a.

METHODS

Published efficacy, safety, and immunogenicity data, in terms of prospectively defined endpoints and later post hoc analyses, from years 1-8 of the PRISMS series are summarized and collated for the first time. Some of the studies of sc IFN beta-1a that evolved from the PRISMS studies are also discussed.

FINDINGS

In the 2-year, double-blind, randomized, placebo-controlled study, IFN beta-1a (22 or 44 mcg three times weekly [tiw]) was associated with significantly lower relapse rates, disability progression, and MRI burden of disease compared with placebo (p <or= 0.05). Subsequently, in the 2-year extension, patients previously receiving placebo were re-randomized to active treatment, and a further 2 years of open-label treatment confirmed good long-term safety and therapeutic efficacy. Follow-up visits at years 7 or 8 (68.2% of initial population) demonstrated a continued benefit for patients originally randomized to the 44-mcg dose compared with those receiving the 22-mcg dose or whose treatment had been delayed by 2 years. Neutralizing antibodies were more common in patients receiving the 22-mcg dose and attenuated treatment efficacy during years 1-4.

CONCLUSION

Class I and long-term data from PRISMS support the use of sc IFN beta-1a tiw as a first-line treatment for MS, as evidenced by sustained efficacy rates, acceptable safety profiles, and high patient retention rates.

Assessing cost-effectiveness in the management of multiple sclerosis

Multiple sclerosis (MS) is one of the most common causes of neurological disability in young and middle-aged adults, with current prevalence rates estimated to be 30 per 100,000 populations. Women are approximately twice as susceptible as males, but males are more likely to have progressive disease. The onset of the disease normally occurs between 20 and 40 years of age, with a peak incidence during the late twenties and early thirties, resulting in many years of disability for a large proportion of patients, many of whom require wheelchairs and some nursing home or hospital care. The aim of this study is to update a previous review which considered the cost-effectiveness of disease-modifying drugs (DMDs), such as interferons and glatiramer acetate, with more up to date therapies, such as mitaxantrone hydrochloride and natalizumab in the treatment of MS. The development and availability of new agents has been accompanied by an increased optimism that treatment regimens for MS would be more effective; that the number, severity and duration of relapses would diminish; that disease progression would be delayed; and that disability accumulation would be reduced. However, doubts have been expressed about the effectiveness of these treatments, which has only served to compound the problems associated with endeavors to estimate the relative cost-effectiveness of such interventions.

The effect of interferon-beta on mouse neural progenitor cell survival and differentiation

Interferon-beta (IFN-beta) is a mainstay therapy for relapse-remitting multiple sclerosis (MS). However, the direct effects of IFN-beta on the central nervous system (CNS) are not well understood. To determine whether IFN-beta has direct neuroprotective effects on CNS cells, we treated adult mouse neural progenitor cells (NPCs) in vitro with IFN-beta and examined the effects on proliferation, apoptosis, and differentiation. We found that mouse NPCs express high levels of IFNalpha/beta receptor (IFNAR). In response to IFN-beta treatment, no effect was observed on differentiation or proliferation. However, IFN-beta treated mouse NPCs demonstrated decreased apoptosis upon growth factor withdrawal. Pathway-specific polymerase chain reaction (PCR) arrays demonstrated that IFN-beta treatment upregulated the STAT 1 and 2 signaling pathway, as well as GFRA2, NOD1, Caspases 1 and 12, and TNFSF10. These results suggest that IFN-beta can directly affect NPC survival, possibly playing a neuroprotective role in the CNS by modulating neurotrophic factors.

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.

Dose response to interferon therapy in multiple sclerosis: an evaluation of the evidence

BACKGROUND

Interferon beta (IFNbeta) is a disease-modifying therapy for multiple sclerosis (MS). Although clinical benefits have been demonstrated in several large, randomized, double-blind studies, the optimal dosing of IFNbeta is controversial.

METHODS

A search was conducted using the key words IFNbeta, multiple sclerosis, Avonex, Rebif, Betaseron/Betaferon, efficacy, MRI, and dose-response relationship in MEDLINE, EMBASE, and other databases to locate relevant pivotal clinical trials, other prospective studies, and systematic reviews evaluating the efficacy and tolerability of IFNbeta published between 1985 and 2007. This review summarizes the findings of these studies with regard to defining the value of high-dose, high-frequency (HDHF) IFNbeta regimens.

REVIEW SUMMARY

All IFNbeta formulations and dosages have demonstrated efficacy in well-designed phase 3 trials. Two head-to-head trials suggesting that HDHF regimens result in increased efficacy contained shortfalls in study design that precluded definitive conclusions.

CONCLUSION

Defining the optimal dose and frequency strategy for IFNbeta in patients with MS is complicated by the differences in dosage, route, and frequency of administration among the various agents. Results of well-controlled pivotal trials do not suggest that HDHF IFNbeta regimens provide better long-term benefits for patients with MS than low-dose or low-frequency regimens. In addition, HDHF therapies may increase the incidence of side-effects and neutralizing antibodies that reduce efficacy over time. Although the two head-to-head comparisons of different IFNbeta therapies found HDHF regimens to be more efficacious than lower-dose/lower-frequency regimens, the design limitations of these studies must be considered when weighing the potential value of the findings for recommending treatment strategies.

Natalizumab treatment in pediatric multiple sclerosis: a case report

Pediatric multiple sclerosis (MS) with manifestations before 16 years of age occurs in 0.4-10.5% of whole MS population. The initial course of the disease is relapsing-remitting with a relapse rate generally higher than that of adults, less than 3% have a primary progressive form. Some recent reports have shown that Interferon beta (IFNbeta) has a strong effect in reducing the relapse rate in children with MS and is well tolerated. We report a 12-year-old girl with MS and a high relapse rate from the onset. Frequent magnetic resonance imaging (MRI) detected persisting inflammatory activity and increase of lesion burden. She continued to present acute relapses and progression of disability in spite of a treatment with IFNbeta-1a at different dosages and the addition of pulse IV steroid treatment. Then, we opted for Natalizumab treatment, recently approved as a monotherapy for patients with MS who experienced inadequate response to other disease modifying therapies and never used till now in pediatric MS. Our patient showed a complete response to Natalizumab with clinical and MRI suppression of disease activity.

Treating relapsing multiple sclerosis with subcutaneous versus intramuscular interferon-beta-1a: modelling the clinical and economic implications

The EVIDENCE trial concluded that administering high-dose/high-frequency subcutaneous (SC) interferon-beta-1a (IFNb1a) was more effective in preventing relapses among patients with relapsing multiple sclerosis (MS) than low-dose weekly intramuscular (IM) IFNb1a after 64 weeks. This analysis utilized discrete-event simulation (DES) to model the potential longer-term clinical and economic implications of this trial. A DES predicting the course of relapsing MS and incorporating the effect of IFNb1a therapy was developed. The model began by randomly reading in actual patient data from the trial to create 1000 patients. Each simulated patient was replicated - one was assigned to receive SC IFNb1a three times a week and the other to receive IM IFNb1a once a week. During the simulation, patients may (i) experience relapses, with associated short- and long-term impacts on costs and disability; (ii) develop new T2 lesions detected by a magnetic resonance imaging scan; (iii) discontinue treatment because of adverse events or lack of response; (iv) advance to secondary progressive MS; or (v) die. Model inputs were mainly obtained from the EVIDENCE trial, but were taken from published literature if they could not be obtained from the trial. Direct medical costs ($US, year 2006 values) to the US payers were primarily obtained by updating a published cost analysis. Costs and benefits were discounted at 3% per annum. Extensive sensitivity analyses were conducted to test the robustness of the model results. Based on 100 replications of 1000 patient pairs over 4 years, SC IFNb1a was predicted to enable more patients to avoid relapse (216 vs 147). Total mean costs per patient (discounted) were $US79 890 with SC IFNb1a versus $US74 485 with IM administration, a net increase of $US5405 per patient. However, SC IFNb1a was estimated to prevent 0.50 relapses and save 23 relapse-free days per patient, yielding incremental cost-effectiveness ratios of $US10 755 per relapse prevented and $US232 per relapse-free day gained. Sensitivity analyses revealed that the result was most sensitive to the treatment efficacy, model time horizon and cost of IFNb1a treatment. Based on the results observed in the EVIDENCE trial, the model predicted that SC IFNb1a would yield greater health benefits over 4 years than IM IFNb1a, at a cost that would seem to be a reasonable trade-off.

Wiendl H, Toyka KV, Rieckmann P, Gold R, Hartung HP, Hohlfeld R. 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.

Switching first-line disease-modifying therapy after failure: impact on the course of relapsing-remitting multiple sclerosis

BACKGROUND

Options for non-responders to relapsing-remitting multiple sclerosis (RRMS) first-line disease-modifying therapies (DMT) are limited. We explored whether switching first-line DMT is effective.

METHODS

Patients with RRMS who first received interferon-beta (IFNB) or glatiramer acetate (GA) were classified in three categories: DMT change because of suboptimal response, DMT change because of other reasons, and no DMT change during follow-up. Outcomes included annualized relapse rate (ARR) and relapse-free proportions.

RESULTS

We identified 597 patients who initiated first-line DMT. For patients who did not change DMT (n = 240), pre-DMT and on-DMT median ARR were 0.50 and 0 (P < 0.0001). At 24 months, 76% (95%CI = 69-81%) of patients who did not change DMT were relapse-free. Of the 155 who switched because of suboptimal response, 101 switched to another first-line DMT. Median ARR pre-DMT, on first DMT and second DMT were: 0.50, 0.55, and 0.25 for switchers from IFNB to GA (IFNB/GA, n = 12) (pre-DMT versus first DMT: P = 0.92; first versus second DMT: P = 0.31); 0.90, 0.50, and 0 for switchers from GA to IFNB (GA/IFNB, n = 18; P = 0.19; P = 0.01); 0.50, 0.68, and 0 for switchers from an IFNB to another IFNB (IFNB/IFNB', n = 71; P = 0.34; P = 0.02). Estimated relapse-free proportion after 24 months of treatment was 42% (95%CI=15-66%) during the period on IFNB versus 53% (95%CI = 17-80%) on GA for IFNB/GA (P = 0.21); 12% (95%CI = 0-40%) on GA versus 87% (95%CI = 59-97%) on IFNB for GA/IFNB (P = 0.001); and 41% (95%CI = 29-52%) on initial IFNB versus 67% (95%CI = 53-79%) on subsequent IFNB for IFNB/IFNB' (P = 0.0001).

CONCLUSIONS

Switching first-line DMT in patients with RRMS failing initial therapy may be effective in many cases.

A novel needle for subcutaneous injection of interferon beta-1a: effect on pain in volunteers and satisfaction in patients with multiple sclerosis

Background

To reduce injection pain and improve satisfaction, a thinner (29-gauge [29G]), sharper (5-bevel) needle than the 27G/3-bevel needle used previously to inject interferon (IFN) beta-1a, 44 or 22 mcg subcutaneously (sc) three times weekly (tiw), was developed for use in multiple sclerosis (MS).

Methods

Two clinical trials in healthy volunteers and five surveys of patients with MS were conducted to assess whether the 29G/5-bevel needle with a Thermo Plastic Elastomer (TPE) needle shield (a sleeve that houses the tip of the needle in a secure location) is an improvement over the 27G/3-bevel needle with a rubber shield for injection of IFN beta-1a, 44 or 22 mcg sc tiw. Parameters assessed were: pain and ease of insertion (healthy volunteer and nurse responses on subjective pain measurement scales); and patient satisfaction (surveys of patients with MS).

Results

In healthy volunteers, the 29G/5-bevel needle with TPE shield was associated with the least perceived pain on the Visual Analog Scale (VAS) and Verbal VAS (VB-VAS); mean VAS pain scores decreased by 40% and skin penetration improved by 69% compared with the 27G/3-bevel needle with standard rubber shield (p < 0.01). Pooled results from surveys of patients with MS indicated that 63% of patients thought that injections were less painful with the 29G/5-bevel needle than the 27G/3-bevel needle. Results from individual surveys indicated that the 29G/5-bevel needle was an improvement over the 27G/3-bevel needle for ease of insertion, injection-site reactions, bruising, burning and stinging.

Conclusion

Together these studies indicate that the 29G/5-bevel needle with the TPE shield is an improvement over the 27G/3-bevel needle with standard rubber shield in terms of pain, ease of insertion and patient satisfaction. These improvements are expected to result in improved compliance in patients with MS treated with IFN beta-1a, 44 or 22 mcg sc tiw.