Long-term clinical outcomes in patients with multiple sclerosis who are initiating disease-modifying therapy with natalizumab compared with BRACETD first-line therapies

Background

Aggressive disease control soon after multiple sclerosis (MS) diagnosis may prevent irreversible neurological damage, and therefore early initiation of a high-efficacy disease-modifying therapy (DMT) is of clinical relevance.

Objectives

Evaluate long-term clinical outcomes in patients with MS who initiated treatment with either natalizumab or a BRACETD therapy (interferon beta, glatiramer acetate, teriflunomide, or dimethyl fumarate).

Design

This retrospective analysis utilized data from MSBase to create a matched population allowing comparison of first-line natalizumab to first-line BRACETD.

Methods

This study included patients who initiated treatment either with natalizumab or a BRACETD DMT within 1 year of MS diagnosis and continued treatment for ⩾6 months, after which patients could switch DMTs or discontinue treatment. Patients had a minimum follow-up time of ⩾60 months from initiation. A subgroup analysis compared the natalizumab group to patients in the BRACETD group who escalated therapy after 6 months. Outcomes included unadjusted annualized relapse rates (ARRs), time-to-first relapse, time-to-first confirmed disability improvement (CDI), and time-to-first confirmed disability worsening (CDW).

Results

After 1:1 propensity score matching, 355 BRACETD patients were matched to 355 natalizumab patients. Patients initiating natalizumab were less likely to experience a relapse over the duration of follow-up, with ARRs [95% confidence interval (CI)] of 0.080 (0.070-0.092) for natalizumab patients and 0.191 (0.178-0.205) for BRACETD patients (p < 0.0001). A Cox regression model of time-to-first relapse showed a reduced risk of relapse for natalizumab patients [hazard ratio (95% CI) of 0.52 (0.42-0.65); p < 0.001] and a more favorable time-to-first CDI. The risk of CDW was similar between groups. The subgroup analysis showed an increased relapse risk as well as a significantly higher risk of CDW for BRACETD patients.

Conclusion

Early initiation of natalizumab produced long-term benefits in relapse outcomes in comparison with BRACETD, regardless of a subsequent escalation in therapy.

Balancing Potential Benefits and Risks of Bruton Tyrosine Kinase Inhibitor Therapies in Multiple Sclerosis During the COVID-19 Pandemic

Bruton tyrosine kinase inhibitors (BTKis) encompass a new class of therapeutics currently being evaluated for the treatment of multiple sclerosis (MS). Whether BTKis affect COVID-19 risk or severity or reduce vaccine efficacy are important but unanswered questions. Here, we provide an overview on BTKi mechanisms relevant to COVID-19 infection and vaccination and review preliminary data on BTKi use in patients with COVID-19. BTKis block B-cell receptor– and myeloid fragment crystallizable receptor–mediated signaling, thereby dampening B-cell activation, antibody class-switching, expansion, and cytokine production. Beyond antibodies, COVID-19 severity and vaccine efficacy appear largely linked to T-cell responses and interferon induction, processes not directly affected by BTKis. Given that B cells have clear roles in antigen presentation to T cells, however, it is possible that BTKis may indirectly interfere with beneficial or detrimental T-cell responses during COVID-19 infection or vaccination. In addition to these possible effects on generating a protective immune response, BTKis may attenuate the hyperinflammatory dysregulation often seen in severe cases of COVID-19 that evolves as a key risk factor in this disease. Currently available outcomes from BTKi-treated patients with COVID-19 are discussed. Clinical trials are currently underway to evaluate the safety and efficacy of BTKis in individuals with MS. Although limited data suggest a potential benefit of BTKis on outcomes for some COVID-19 patients, data from adequately powered, prospective and randomized clinical trials are lacking. Likewise, the specific effect of BTKis on the safety and efficacy of COVID-19 vaccines remains to be determined. Any potential unknown risks that BTKi therapy may present to the patient relative to COVID-19 infection, severity, and vaccine efficacy must be balanced with the importance of timely intervention to prevent or minimize MS progression.

Myeloid cells - targets of medication in multiple sclerosis

Discussions of multiple sclerosis (MS) pathophysiology tend to focus on T cells and B cells of the adaptive immune response. The innate immune system is less commonly considered in this context, although dendritic cells, monocytes, macrophages and microglia - collectively referred to as myeloid cells - have prominent roles in MS pathogenesis. These populations of myeloid cells function as antigen-presenting cells and effector cells in neuroinflammation. Furthermore, a vicious cycle of interactions between T cells and myeloid cells exacerbates pathology. Several disease-modifying therapies are now available to treat MS, and insights into their mechanisms of action have largely focused on the adaptive immune system, but these therapies also have important effects on myeloid cells. In this Review, we discuss the evidence for the roles of myeloid cells in MS and the experimental autoimmune encephalomyelitis model of MS, and consider how interactions between myeloid cells and T cells and/or B cells promote MS pathology. Finally, we discuss the direct and indirect effects of existing MS medications on myeloid cells.

Rates of Early Treatment for US Veterans With Multiple Sclerosis

Background: Early treatment of patients with multiple sclerosis (MS) may prevent neurological damage and reduce the risk of disability. However, little is known about the timing of treatment initiation following diagnosis and long-term outcomes in the general population of the Department of Veterans Affairs (VA) benefits-eligible patients. Objective: Our objective was to characterize treatment for MS patients in the VA at various time points following diagnosis date. Methods: In our historical database cohort study of US veterans, we calculated the proportion of MS patients from 1999 through 2010 with at least one prescription for a medication used to treat the condition at 6, 12, 24, 36, 48, 60, and 72 months following the index date. We also stratified the treatments given into 3 categories based on their role within the course of the disease: disease modifying, relapse, and symptom. Finally, we performed our calculations separately by MS subtype: relapsing-remitting, secondary-progressive, primary-progressive, and progressive-relapsing. Results: A total of 6803 patients were included in the analysis. Only 27.4% of MS patients received a prescription for MS medication within the first 6 months after diagnosis. The most common treatments were interferon β-1a, glatiramer, amantadine, and prednisone, with disease-modifying agents being more than twice as frequently prescribed as medications for relapse or symptoms. Patients with relapsing-remitting MS were the most likely to be treated, followed by progressive-relapsing MS. Conclusions: Our results suggest that treatment rates are low in VA MS patients in the 6 years following their first diagnosis of MS.

Multiple Sclerosis Therapy With Disease-Modifying Treatments in Germany: The PEARL (ProspEctive phArmacoeconomic cohoRt evaluation) Noninterventional Study Protocol

Background

Patients with multiple sclerosis (MS) require long-term therapy and have a wide variety of needs for health-related support. The efficacy and safety of MS therapy, as assessed by both clinicians and patients, are important parameters that need to be considered. However, few studies combine data on efficacy and safety outcomes with pharmacoeconomic data.

Objective

Here, we present the study design of the ProspEctive phArmacoeconomic cohoRt evaluation (PEARL), a prospective, multicenter, noninterventional cohort study on patients with relapsing-remitting MS (RRMS) treated with disease-modifying treatments (DMTs).

Methods

During a prospective observational phase of 24 months per patient, PEARL evaluated clinical and patient-perceived efficacy and safety measures, as well as pharmacoeconomic data on RRMS patients treated with DMTs—interferon beta and glatiramer acetate. Measurements of the patients' perceptions included the assessment of patient-reported quality of life, treatment satisfaction, and compliance. The study was planned to include 1800 outpatients from 180 German neurological practices who had continuously been treated with an approved DMT for at least 30 days. The primary statistical analyses of the PEARL study will be descriptive. Particular focus will be on specific subgroups, such as patients who switched DMTs during therapy and patients with disease worsening or disease activity. Subgroups will be compared using stratified analyses.

Results

Data collection for PEARL started in September 2010 and ended in July 2013. As of July 2015, the study is completed and is currently being analyzed and written up.

Conclusions

PEARL is evaluating both the health status and resource utilization of RRMS patients treated with DMTs in Germany. The combination of pharmacoeconomic data with clinical and patients' self-perceived efficacy and safety outcomes will add useful information to the currently incomplete picture of the overall RRMS burden in Germany.

Glatiramer acetate: a review of its use in patients with relapsing-remitting multiple sclerosis and in delaying the onset of clinically definite multiple sclerosis

Glatiramer acetate (Copaxone(®)) is a synthetic analogue of the multiple sclerosis (MS)-associated antigen, myelin basic protein. Although its exact mechanisms of action in MS remain to be fully elucidated, the key mechanisms of action of glatiramer acetate appear to be modulation of the inflammatory response and neuroprotective and/or neuroregenerative effects. Subcutaneous glatiramer acetate is indicated for the treatment of adult patients with relapsing-remitting MS (RRMS) and the treatment of patients who have experienced a well-defined first clinical episode and have magnetic resonance imaging (MRI) features consistent with MS or have been determined to be at high risk of developing clinically definite MS (CDMS). In clinical trials in patients with RRMS, glatiramer acetate reduced the frequency of relapses and reduced the burden and activity of disease on MRI, was more effective than placebo and showed generally similar efficacy to subcutaneous interferon (IFN) β-1a and IFNβ-1b. Furthermore, the beneficial effects of glatiramer acetate were sustained during up to 15 years of treatment in an extension study. In patients with clinically isolated syndrome (CIS), glatiramer acetate significantly delayed the onset of CDMS compared with placebo. The drug was generally well tolerated in these patient populations, with injection-site reactions being the most commonly occurring adverse events. Therefore, glatiramer acetate remains a valuable first-line option in the treatment of RRMS and is an option for delaying the onset of CDMS in patients with CIS.

Cerebrospinal fluid proteome comparison between multiple sclerosis patients and controls

OBJECTIVES

The aim of the present study was to identify proteins in cerebrospinal fluid (CSF) with different abundance between patients with relapsing-remitting multiple sclerosis (RRMS) and controls. Such proteins may be diagnostic biomarkers and contribute with novel information about the disease pathogenesis.

MATERIALS AND METHODS

Cerebrospinal fluid from patients with RRMS (n = 17) and controls (n = 17) were trypsin digested and analyzed in a label-free fashion using liquid chromatography mass spectrometry. The resulting data were analyzed using SearchGUI, PeptideShaker, and the Progenesis software.

RESULTS

Two hundred and ninety-one proteins were identified, of which 32 were significantly differentially abundant between the patients with RRMS and controls (P-value ≤ 0.05, two or more peptides quantified). Among these were proteins which previously have been linked to MS, including immunoglobulin subunits, vitamin D-binding protein, apolipoprotein D, kallikrein-6, neuronal pentraxin receptor, Dickkopf-related protein 3, and contactin-1.

CONCLUSION

The study provides an overview of differentially abundant proteins between RRMS and controls, and a few of these are further discussed. It should be stressed that a larger verification study is needed to reveal the potential value of these proteins as biomarkers for RRMS and their involvement in the disease pathogenesis.

[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.

Nasal administration of drugs as a new non-invasive strategy for efficient treatment of multiple sclerosis

We investigated the efficiency of nasal drug administration as a new non-invasive treatment strategy for MS. Glatiramer Acetate (GA) and GA-Cannabidiol (CBD) combination administered in nasal delivery system (NDS) resulted in a statistically significant decrease of clinical scores and inflammatory cytokine expression in experimental autoimmune encephalomyelitis (EAE) mice. Even a suboptimal dose of Prednisolone in NDS was effective in preventing the clinical signs of the disease. Neuron regeneration was observed in the hippocampus of EAE mice treated with GA-CBD in NDS. This work shows that nasal administration improved drug efficiency and stimulates further research for a non-invasive strategy for MS.

Review of the pharmacoeconomics of early treatment of multiple sclerosis using interferon beta

Multiple sclerosis (MS) is a common neurological disease with increasing incidence and prevalence. Onset of disease is most frequently in young adulthood when productivity is usually highest; it is of chronic nature and, in the majority of patients, it will result in accumulation of disability. Due to loss of productivity in patients and caregivers as well as high expenses for medical treatment, MS is considered a disease with high economic burden for patients and society. Several drugs have been approved for treatment of MS. While treatment ameliorates the course of the disease, it is very costly; therefore, pharmacoeconomics, evaluating costs and effects of disease-modifying treatment in MS, has become an important issue. Here, we review the economic impact and treatment strategies of MS and discuss recent studies on pharmacoeconomics of early treatment with interferon beta.

From injection therapies to natalizumab: views on the treatment of multiple sclerosis

Discoveries of the mechanisms that underlie the pathogenesis of multiple sclerosis have been acquired at an impressive rate over the last few decades and, as a consequence, a growing number of treatments are becoming available for this disease. This review first analyzes the experience from the early stages of the disease-modifying therapies, then, expanding on the concept of early treatment for improved outcomes, it focuses on natalizumab and its major complication, progressive multifocal leukoencephalopathy. We offer views on the risks associated with the use of natalizumab by underscoring the importance of the JC virus serology and by providing preliminary data on our experience with the extended interval dosing of natalizumab. This approach, which advocates individualized treatment plans, raises the question of the minimum effective natalizumab dose. Extended interval dosing suggests efficacy can be maintained while providing advantages of costs and convenience over regular monthly dosing. More data examining this strategy are necessary.

Pharmacogenomics in neurology: current state and future steps

In neurology, as in any other clinical specialty, there is a need to develop treatment strategies that allow stratification of therapies to optimize efficacy and minimize toxicity. Pharmacogenomics is one such method for therapy optimization: it aims to elucidate the relationship between human genome sequence variation and differential drug responses. Approaches have focused on candidate approaches investigating absorption-, distribution-, metabolism, and elimination (ADME)-related genes (pharmacokinetic pathways), and potential drug targets (pharmacodynamic pathways). To date, however, only few genetic variants have been incorporated into clinical algorithms. Unfortunately, a large number of studies have thrown up contradictory results due to a number of deficiencies, including small sample sizes, inadequate phenotyping, and genotyping strategies. Thus, there still exists an urgent need to establish biomarkers that could help to select for patients with an optimal benefit to risk relationship. Here we review recent advances, and limitations, in pharmacogenomics for agents used in neuroimmunology, neurodegenerative diseases, ischemic stroke, epilepsy, and primary headaches. Further work is still required in all of these areas, which really needs to progress on several fronts, including better standardized phenotyping, appropriate sample sizes through multicenter collaborations and judicious use of new technological advances such as genome-wide approaches, next generation sequencing and systems biology. In time, this is likely to lead to improvements in the benefit-harm balance of neurological therapies, cost efficiency, and identification of new drugs.

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.

The combination of interferon-beta and HMG-CoA reductase inhibition in multiple sclerosis: enthusiasm lost too soon?

Recent studies support the notion that statins, widely prescribed cholesterol-lowering agents, may target key elements in the immunological cascade leading to inflammation and tissue damage in the pathogenesis of multiple sclerosis (MS). Compelling experimental and observational clinical studies highlighted the possibility that statins may also exert immunomodulatory synergy with approved MS drugs, resulting in several randomized clinical trials testing statins in combination with interferon-beta (IFN-β). Some data, however, suggest that this particular combination may not be clinically beneficial, and might actually have a negative effect on the disease course in some patients with MS. In this regard, a small North American trial indicated that atorvastatin administered in combination with IFN-β may increase disease activity in relapsing-remitting MS. Although other trials did not confirm this finding, the enthusiasm for studies with statins dwindled. This review aims to provide a comprehensive overview of the completed clinical trials and reports of the interim analyses evaluating the combination of IFN-β and statins in MS. Moreover, we try to address the evident question whether usage of this combination routinely requires caution, since the number of IFN-β-treated MS patients receiving statins for lowering of cholesterol is expected to grow.

Interferon-β-1b: a review of its use in multiple sclerosis

Interferon-β-1b has been used as a disease-modifying therapy in multiple sclerosis (MS) for many years. Although its mechanism of action in MS has not been fully elucidated, it appears to involve immunomodulatory effects mediated by interactions with specific receptors. Large, randomized, multicentre, clinical trials of 2-3.5 years' duration have demonstrated the efficacy of interferon-β-1b 250 μg subcutaneously every other day in patients with a first clinical event suggestive of MS (i.e. those with clinically isolated syndrome [CIS]) and in those with relapsing-remitting MS (RRMS). In terms of its efficacy on primary (or co-primary) endpoints, interferon-β-1b significantly reduced the risk of developing clinically definite MS compared with placebo in patients with CIS in the BENEFIT study. In patients with RRMS, interferon-β-1b was associated with a significantly lower annualized relapse rate and a significantly higher proportion of relapse-free patients compared with placebo in a registration trial conducted by the Interferon-β MS Study Group. The INCOMIN trial in patients with RRMS showed a significant advantage of interferon-β-1b over intramuscular interferon-β-1a in terms of the percentage of relapse- and progression-free patients and the proportion of patients without new MRI-documented lesions. Other active-comparator trials in RRMS used a variety of primary (or co-primary) endpoints and showed no significant differences between interferon-β-1b and either subcutaneous glatiramer acetate (BECOME and BEYOND trials) or subcutaneous interferon-β-1a (Danish MS Group trial) for these outcomes. In patients with secondary progressive MS (SPMS), the European Study Group showed that interferon-β-1b significantly increased the time to confirmed disease progression compared with placebo, although there was no significant between-group difference for this primary endpoint in a similar trial conducted by the North American Study Group. The studies allowed inclusion of patients with superimposed relapse, and both trials showed a significant reduction in annualized relapse rate with interferon-β-1b. The most frequently reported adverse events with interferon-β-1b are flu-like symptoms and injection-site reactions, which can usually be managed. The incidence of these adverse events generally declines markedly after the first year of treatment. Lymphopenia is the most frequently reported laboratory abnormality and occurs in the majority of patients. Depression, suicidal ideation and injection-site necrosis were the most serious adverse events reported with interferon-β-1b in clinical trials. Long-term safety data over a 16-year follow-up period showed no unexpected adverse events among patients treated with interferon-β-1b. Thus, interferon-β-1b is a well established, first-line, disease-modifying therapy that has demonstrated efficacy in newly emerging MS, RRMS and SPMS with superimposed relapse in well designed clinical trials, and has a generally manageable tolerability profile, with no unexpected adverse events after many years of follow-up.

Comparison of efficiency of terminal differentiation of oligodendrocytes from induced pluripotent stem cells versus embryonic stem cells in vitro

Oligodendrocytes are the myelinating cells of the central nervous system (CNS), and defects in these cells can result in the loss of CNS functions. Although oligodendrocyte progenitor cells transplantation therapy is an effective cure for such symptoms, there is no readily available source of these cells. Recent studies have described the generation of induced pluripotent stem cells (iPS cells) from somatic cells, leading to anticipation of this technique as a novel therapeutic tool in regenerative medicine. In this study, we evaluated the ability of iPS cells derived from mouse embryonic fibroblasts to differentiate into oligodendrocytes and compared this with the differential ability of mouse embryonic stem cells (ES cells). Experiments using an in vitro oligodendrocyte differentiation protocol that was optimized to ES cells demonstrated that 2.3% of iPS cells differentiated into O4(+) oligodendrocytes compared with 24.0% of ES cells. However, the rate of induction of A2B5(+) oligodendrocyte precursor cell (OPC) was similar for both iPS-derived cells and ES-derived cells (14.1% and 12.6%, respectively). These findings suggest that some intracellular factors in iPS cells inhibit the terminal differentiation of oligodendrocytes from the OPC stage.

Potential of a unique antibody gene signature to predict conversion to clinically definite multiple sclerosis

We identified a unique antibody gene mutation pattern (i.e. "signature") in cerebrospinal fluid (CSF) B cells from multiple sclerosis (MS) patients not present in control populations. Prevalence of the signature in CSF B cells of patients at risk to develop MS predicted conversion to MS with 91% accuracy in a small cohort of clinically isolated syndrome patients. If confirmed, signature prevalence would be a novel genetic diagnostic tool candidate for patients with early demyelinating disease of the central nervous system.

Immunotherapy of multiple sclerosis

Multiple sclerosis (MS) is regarded as a prototypic inflammatory autoimmune central nervous system disorder causing neurological disability in young adults. Recommended basic immunomodulatory therapies of MS are currently interferon beta and glatiramer acetate. Both have proven to be clinically and paraclinically effective and clinical evidence suggests that treatment should be initiated as early as possible. However, despite the fact that therapeutic options for MS have significantly been widened over the past decade there is still tremendous activity in the search for new treatment options for MS. One important development in the field is reflected by the substantial number of promising results for oral therapies. Various phase III clinical trials are currently being initiated or are already underway evaluating the efficacy of a variety of orally administered agents, including cladribine, teriflunomide, laquinimod, fingolimod and fumaric acid. It is hoped that these oral therapies for MS further broaden our armament for MS therapy.

Nicotinic acid-mediated activation of both membrane and nuclear receptors towards therapeutic glucocorticoid mimetics for treating multiple sclerosis

Acute attacks of multiple sclerosis (MS) are most commonly treated with glucocorticoids, which can provide life-saving albeit only temporary symptomatic relief. The mechanism of action (MOA) is now known to involve induction of indoleamine 2,3-dioxygenase (IDO) and interleukin-10 (IL-10), where IL-10 requires subsequent heme oxygenase-1 (HMOX-1) induction. Ectopic expression studies reveal that even small changes in expression of IDO, HMOX-1, or mitochondrial superoxide dismutase (SOD2) can prevent demyelination in experimental autoimmune encephalomyelitis (EAE) animal models of MS. An alternative to glucocorticoids is needed for a long-term treatment of MS. A distinctly short list of endogenous activators of both membrane G-protein-coupled receptors and nuclear peroxisome proliferating antigen receptors (PPARs) demonstrably ameliorate EAE pathogenesis by MOAs resembling that of glucocorticoids. These dual activators and potential MS therapeutics include endocannabinoids and the prostaglandin 15-deoxy-Δ^12,14-PGJ₂. Nicotinamide profoundly ameliorates and prevents autoimmune-mediated demyelination in EAE via maintaining levels of nicotinamide adenine dinucleotide (NAD), without activating PPAR nor any G-protein-coupled receptor. By comparison, nicotinic acid provides even greater levels of NAD than nicotinamide in many tissues, while additionally activating the PPARγ-dependent pathway already shown to provide relief in animal models of MS after activation of GPR109a/HM74a. Thus nicotinic acid is uniquely suited for providing therapeutic relief in MS. However nicotinic acid is unexamined in MS research. Nicotinic acid penetrates the blood brain barrier, cures pellagric dementia, has been used for over 50 years clinically without toxicity, and raises HDL concentrations to a greater degree than any pharmaceutical, thus providing unparalleled benefits against lipodystrophy. Summary analysis reveals that the expected therapeutic benefits of high-dose nicotinic acid administration far outweigh any known adverse risks in consideration for the treatment of multiple sclerosis.

Disease-modifying agents for multiple sclerosis: recent advances and future prospects

Multiple sclerosis (MS) is a chronic autoimmune disease of the CNS. Currently, six medications are approved for immunmodulatory and immunosuppressive treatment of the relapsing disease course and secondary-progressive MS. In the first part of this review, the pathogenesis of MS and its current treatment options are discussed. During the last decade, our understanding of autoimmunity and the pathogenesis of MS has advanced substantially. This has led to the development of a number of compounds, several of which are currently undergoing clinical testing in phase II and III studies. While current treatment options are only available for parenteral administration, several oral compounds are now in clinical trials, including the immunosuppressive agents cladribine and laquinimod. A novel mode of action has been described for fingolimod, another orally available agent, which inhibits egress of activated lymphocytes from draining lymph nodes. Dimethylfumarate exhibits immunomodulatory as well as immunosuppressive activity when given orally. All of these compounds have successfully shown efficacy, at least in regards to the surrogate marker contrast-enhancing lesions on magnetic resonance imaging. Another class of agents that is highlighted in this review are biological agents, namely monoclonal antibodies (mAb) and recombinant fusion proteins. The humanized mAb daclizumab inhibits T-lymphocyte activation via blockade of the interleukin-2 receptor. Alemtuzumab and rituximab deplete leukocytes and B cells, respectively; the fusion protein atacicept inhibits specific B-cell growth factors resulting in reductions in B-cells and plasma cells. These compounds are currently being tested in phase II and III studies in patients with relapsing MS. The concept of neuro-protection and -regeneration has not advanced to a level where specific compounds have entered clinical testing. However, several agents approved for conditions other than MS are highlighted. Finally, with the advent of these highly potent novel therapies, rare, but potentially serious adverse effects have been noted, namely infections and malignancies. These are critically reviewed and put into perspective.

PEG minocycline-liposomes ameliorate CNS autoimmune disease

Background

Minocycline is an oral tetracycline derivative with good bioavailability in the central nervous system (CNS). Minocycline, a potent inhibitor of matrix metalloproteinase (MMP)-9, attenuates disease activity in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Potential adverse effects associated with long-term daily minocycline therapy in human patients are concerning. Here, we investigated whether less frequent treatment with long-circulating polyethylene glycol (PEG) minocycline liposomes are effective in treating EAE.

Findings

Performing in vitro time kinetic studies of PEG minocycline-liposomes in human peripheral blood mononuclear cells (PBMCs), we determined that PEG minocycline-liposome preparations stabilized with CaCl₂ are effective in diminishing MMP-9 activity. Intravenous injections of PEG minocycline-liposomes every five days were as effective in ameliorating clinical EAE as daily intraperitoneal injections of minocycline. Treatment of animals with PEG minocycline-liposomes significantly reduced the number of CNS-infiltrating leukocytes, and the overall expression of MMP-9 in the CNS. There was also a significant suppression of MMP-9 expression and proteolytic activity in splenocytes of treated animals, but not in CNS-infiltrating leukocytes. Thus, leukocytes gaining access to the brain and spinal cord require the same absolute amount of MMP-9 in all treatment groups, but minocycline decreases the absolute cell number.

Conclusions

Our data indicate that less frequent injections of PEG minocycline-liposomes are an effective alternative pharmacotherapy to daily minocycline injections for the treatment of CNS autoimmune diseases. Also, inhibition of MMP-9 remains a promising treatment target in EAE and patients with MS.

Interferon-beta-1b: in newly emerging multiple sclerosis

The mechanism of action of interferon-[beta]-1b in multiple sclerosis (MS) is not clearly understood, but is thought to involve immunoregulatory activities, including enhancing the suppressor activity of peripheral blood mononuclear cells. In the planned 3-year analysis of the BENEFIT study in patients with a single clinical event suggestive of MS, the relative risk of clinically definite (CD) MS was reduced by 41% in those receiving interferon-[beta]-1b 250 [micro]g every other day for 3 years (early-treatment group) compared with patients who were initially randomized to placebo then switched to interferon-[beta]-1b 250 [micro]g every other day at the end of 2 years or at the onset of CDMS (delayed-treatment group) [p < 0.01]. The relative risk of confirmed progression of the expanded disability status scale (EDSS) was reduced by 40% in the early-treatment group compared with the delayed-treatment group over 3 years (p < 0.05). At the end of the 2-year, randomized, placebo-controlled period of the BENEFIT study, the risk of developing CDMS (p < 0.0001) and McDonald-defined MS (p < 0.00001) was significantly lower in the interferon-[beta]-1b group than in the placebo group, and in the magnetic resonance imaging analysis, fewer newly active lesions developed in the interferon-[beta]-1b group (p < 0.001). Interferon-[beta]-1b was generally well tolerated. In the 3-year BENEFIT study, neutralizing activity, which was reported in about one-third of the early-treatment group, had no effect on outcome.

Magnetic resonance imaging in clinical trials

PURPOSE OF REVIEW

The aim of this article is to review the latest clinical trials in neurological diseases where magnetic resonance imaging was used to assess treatment outcome.

RECENT FINDINGS

The unique sensitivity of magnetic resonance imaging for detecting disorders in the brain has made it an attractive noninvasive tool for assessing treatment efficacy in several diseases. Volumetric and functional magnetic resonance imaging have proved to represent robust biomarkers for the evaluation of anti-Alzheimer treatments, and have demonstrated a significant impact of cholinesterase inhibitors. The optimization of thrombolytic therapy in acute ischemic stroke has concentrated on the quantification of the ischemic penumbra, using perfusion-weighted and diffusion-weighted imaging. Standard assessment of T2 or fluid-attenuated inversion recovery lesion load remains the method of choice to evaluate new therapeutic strategy in multiple sclerosis. Other nonconventional quantitative magnetic resonance imaging techniques such as magnetic resonance volumetry, magnetization transfer imaging, diffusion-weighted imaging, or magnetic resonance spectroscopy are increasingly used in the field.

SUMMARY

Magnetic resonance imaging has become a major surrogate marker of treatment response in clinical trials of neurological disorders, offering the possibility to reduce the required sample size or to shorten the duration of the trial.

Translation towards personalized medicine in Multiple Sclerosis

In recent years the realization that the concept 'one drug fits all' - does not work, created the need to shift gears from 'treating the disease' to 'treating the patient', and implementation of 'Personalized Medicine' where treatment is tailored to the individual. In chronic and progressive diseases, such as Multiple Sclerosis (MS), the need for tailored therapeutics is especially imperative, as the consequences of an ineffective medication might be irreversible dysfunction. In recent years accumulating evidence indicates that MS is not a single disease and that patients with different disease subtypes respond differently to a medication. Environment and genetics are among the factors that determine disease subtype and activity, and the patient's response to medication. Additional factors include demographic characteristics such as gender and age, as well as chrono-biological indicators. During the last few years, advances and availability of new technologies have brought genome-wide gene expression profiling studies to many medical fields, including MS. Genomic technologies have also stimulated pharmacogenetics studies, that aim to identify genetic factors that affect response to treatment. However, pharmacogenetics information is still immature to allow its translation to clinical practice in MS. Notably, one of the major limitations in obtaining reproducible data across MS pharmacogenetics studies has been the lack of a consensus as to the appropriate method for determining clinical response. In light of the rapid advances in technology and progress in applying individualized treatment strategies in other diseases, 'Personalized Medicine' for MS seems feasible within the coming years.