Mechanisms of action of disease-modifying agents and brain volume changes in multiple sclerosis

Shifting imaging targets in multiple sclerosis: from inflammation to neurodegeneration

Classically multiple sclerosis (MS) has been regarded as an auto-immune disease of the white matter in the central nervous system leading to severe disability over the course of several decades. Current therapeutic strategies in MS are mostly based on either immune suppression or immune modulation. Although effective in decreasing relapse frequency and severity as well as delaying disease progression, MS pathology ensues nonetheless. In the last decade it became evident that gray matter pathology plays an important role in disease progression and helps explaining certain aspects of MS-related disability such as cognitive decline. Conventional MRI outcome measures commonly used in clinical trials are sufficient to demonstrate an anti-inflammatory drug-effect but lack pathological specificity and are poor to moderate predictors of disability. In this article, we review new insights in gray matter pathology and functional reorganization in MS and how these novel fields in MS research may validate and establish new MRI outcome measures, aid in the development of new therapeutic strategies for neuroprotection and neurorepair, and may lead to development of novel predictive measures of disability and disease progression in MS.

[Intravenous immunoglobulin: immunomodulatory key of the immune system]

The mechanisms of action of intravenous immunoglobulins (IVIG) are complex and mostly reproduce those of the natural immunoglobulin G (IgG) in our organism. The therapeutic doses used range from substitutive (200-400mg/kg of body weight) in immunodeficiencies to high doses (1-2g/kg of body weight) in autoimmune or inflammatory diseases. The paradoxical pro- or anti-inflammatory effects of IVIG are based on the modulation of the expression of activating versus inhibitory Fc receptors, the type and stage of maturation of the target cell. This huge diversity of actions may explain the extensive and varied range of clinical applications of IVIG nowadays (immunodeficiencies, autoimmune diseases, degenerative diseases such as Alzheimer's, and cancer). On the other hand, biological therapies with monoclonal antibodies mostly consist of IgG molecules with unique antigen specificity, and currently represent a therapeutic field expanding in various pathologies including cancer and diseases of immunological basis. The effects of IgG are added to their specific effects on molecules target.

Clinical applications of imaging disease burden in multiple sclerosis: MRI and advanced imaging techniques

This review will address the critical role of radiographic techniques in monitoring multiple sclerosis disease course and response to therapeutic interventions using conventional imaging. We propose an algorithm of obtaining a contrast-enhanced brain MRI 6 months after starting a disease-modifying therapy, and considering a gadolinium-enhancing lesion on that scan to indicate suboptimal response to therapy. New or enlarging T2 lesions should be followed on scans at 6-month intervals to assess for change, and the presence of one or more enhancing lesions on a 6- or 12-month scan, or two or more new or enlarging T2 lesions on a 12-month scan should prompt consideration of therapy change. New techniques such as PET imaging, magnetic resonance spectroscopy, magnetic resonance relaxometry, iron-sensitive imaging and perfusion MRI will also be overviewed, with their potential roles in monitoring disease course and activity.

Regulatory effects of programmed cell death 4 (PDCD4) protein in interferon (IFN)-stimulated gene expression and generation of type I IFN responses

The precise mechanisms by which the activation of interferon (IFN) receptors (IFNRs) ultimately controls mRNA translation of specific target genes to induce IFN-dependent biological responses remain ill defined. We provide evidence that IFN-α induces phosphorylation of programmed cell death 4 (PDCD4) protein on Ser67. This IFN-α-dependent phosphorylation is mediated by either the p70 S6 kinase (S6K) or the p90 ribosomal protein S6K (RSK) in a cell-type-specific manner. IFN-dependent phosphorylation of PDCD4 results in downregulation of PDCD4 protein levels as the phosphorylated form of PDCD4 interacts with the ubiquitin ligase β-TRCP (β-transducin repeat-containing protein) and undergoes degradation. This process facilitates IFN-induced eukaryotic translation initiation factor 4A (eIF4A) activity and binding to translation initiation factor eIF4G to promote mRNA translation. Our data establish that PDCD4 degradation ultimately facilitates expression of several ISG protein products that play important roles in the generation of IFN responses, including IFN-stimulated gene 15 (ISG15), p21(WAF1/CIP1), and Schlafen 5 (SLFN5). Moreover, engagement of the RSK/PDCD4 pathway by the type I IFNR is required for the suppressive effects of IFN-α on normal CD34(+) hematopoietic precursors and for antileukemic effects in vitro. Altogether, these findings provide evidence for a unique function of PDCD4 in the type I IFN system and indicate a key regulatory role for this protein in mRNA translation of ISGs and control of IFN responses.

Two-year serial whole-brain N-acetyl-L-aspartate in patients with relapsing-remitting multiple sclerosis

OBJECTIVES

To test the hypotheses that 1) patients with relapsing-remitting multiple sclerosis (RR-MS) exhibit a quantifiable decline in their whole-brain concentration of the neural marker N-acetyl-L-aspartate (WBNAA), that is 2) more sensitive than clinical changes and 3) may provide a practical outcome measure for proof-of-concept and larger phase III clinical trials.

METHODS

Nineteen patients (5 men and 14 women) with clinically definite RR-MS, who were 33 ± 5 years old (mean ± SD), had a disease duration of 47 ± 28 months, and had a median Expanded Disability Status Scale (EDSS) score of 1.0 (range 0-5.5), underwent MRI and proton magnetic resonance spectroscopy ((1)H-MRS) semiannually for 2 years (5 time points). Eight matched control subjects underwent the protocol annually (3 time points). Their global N-acetyl-L-aspartate (1)H-MRS signal was converted into absolute amounts by phantom replacement and into WBNAA by dividing with the brain parenchymal volume, V(B), from MRI segmentation.

RESULTS

The baseline WBNAA of the patients (10.5 ± 1.7 mM) was significantly lower than that of the controls (12.3 ± 1.3 mM; p < 0.002) and declined significantly (5%/year, p < 0.002) vs that for the controls who did not show a decline (0.4%/year, p > 0.7). Likewise, V(B) values of the patients also declined significantly (0.5%/year, p < 0.0001), whereas those of the controls did not (0.2%/year, p = 0.08). The mean EDSS score of the patients increased insignificantly from 1.0 to 1.5 (range 0-6.0) and did not correlate with V(B) or WBNAA.

CONCLUSIONS

WBNAA of patients with RR-MS declined significantly at both the group and individual levels over a 2-year time period common in clinical trials. Because of the small sample sizes required to establish power, WBNAA can be incorporated into future studies.

Changes in regional brain morphology in neuropsychiatric systemic lupus erythematosus

OBJECTIVE

Neuropsychiatric lupus (NPSLE) is a severe and potentially life-threatening condition, reported to occur in 25%-70% of patients with systemic lupus erythematosus (SLE). Brain imaging, especially magnetic resonance imaging, is frequently used to diagnose or exclude overt cerebral pathologies such as edema, hemorrhage, and central thrombosis. More advanced imaging techniques have been applied to demonstrate subtle changes in regional cerebral blood flow and brain structure. We investigated changes in regional gray-matter (GM) volume in SLE patients without neurological manifestations and NPSLE patients at an acute stage of the disease.

METHODS

Using high-resolution structural images and voxel-based morphometry (VBM), we investigated regional GM volume in 20 NPSLE patients (within 2 weeks of the acute manifestation), 18 SLE patients without neurologic and/or psychiatric manifestations, and 18 healthy controls.

RESULTS

VBM analyses revealed several regions of GM atrophy in various parts of the brain in NPSLE and SLE patients. GM atrophy was seen in both groups in the temporal and parietal lobes and was most pronounced in the posterior thalamus bilaterally. Both groups showed an increase in regional GM volume in the posterior parahippocampal gyrus.

CONCLUSION

Our data suggest that changes in regional brain morphology are present in acute NPSLE, but also in SLE (as compared to controls), which might be indicative of a subclinical neurodegenerative process. Further research is needed to investigate whether specific neuropsychiatric symptoms are related to these changes.

Association between pathological and MRI findings in multiple sclerosis

The identification of pathological processes that could be targeted by therapeutic interventions is a major goal of research into multiple sclerosis (MS). Pathological assessment is the gold standard for such identification, but has intrinsic limitations owing to the limited availability of autopsy and biopsy tissue. MRI has gained a leading role in the assessment of MS because it allows doctors to obtain an ante mortem picture of the degree of CNS involvement. A number of correlative pathological and MRI studies have helped to define in vivo the pathological substrates of MS in focal lesions and normal-appearing white matter, not only in the brain, but also in the spinal cord. These studies have resulted in the identification of aspects of pathophysiology that were previously neglected, including grey matter involvement and vascular pathology. Despite these important achievements, numerous open questions still need to be addressed to resolve controversies about how the pathology of MS results in fixed neurological disability.

Clinical correlates of grey matter pathology in multiple sclerosis

Traditionally, multiple sclerosis has been viewed as a disease predominantly affecting white matter. However, this view has lately been subject to numerous changes, as new evidence of anatomical and histological changes as well as of molecular targets within the grey matter has arisen. This advance was driven mainly by novel imaging techniques, however, these have not yet been implemented in routine clinical practice. The changes in the grey matter are related to physical and cognitive disability seen in individuals with multiple sclerosis. Furthermore, damage to several grey matter structures can be associated with impairment of specific functions. Therefore, we conclude that grey matter damage - global and regional - has the potential to become a marker of disease activity, complementary to the currently used magnetic resonance markers (global brain atrophy and T2 hyperintense lesions). Furthermore, it may improve the prediction of the future disease course and response to therapy in individual patients and may also become a reliable additional surrogate marker of treatment effect.

Serum lipid profiles are associated with disability and MRI outcomes in multiple sclerosis

Background

The breakdown of the blood-brain-barrier vascular endothelium is critical for entry of immune cells into the MS brain. Vascular co-morbidities are associated with increased risk of progression. Dyslipidemia, elevated LDL and reduced HDL may increase progression by activating inflammatory processes at the vascular endothelium.

Objective

To assess the associations of serum lipid profile variables (triglycerides, high and low density lipoproteins (HDL, LDL) and total cholesterol) with disability and MRI measures in multiple sclerosis (MS).

Methods

This study included 492 MS patients (age: 47.1 ± 10.8 years; disease duration: 12.8 ± 10.1 years) with baseline and follow-up Expanded Disability Status Score (EDSS) assessments after a mean period of 2.2 ± 1.0 years. The associations of baseline lipid profile variables with disability changes were assessed. Quantitative MRI findings at baseline were available for 210 patients.

Results

EDSS worsening was associated with higher baseline LDL (p = 0.006) and total cholesterol (p = 0.001, 0.008) levels, with trends for higher triglyceride (p = 0.025); HDL was not associated. A similar pattern was found for MSSS worsening. Higher HDL levels (p < 0.001) were associated with lower contrast-enhancing lesion volume. Higher total cholesterol was associated with a trend for lower brain parenchymal fraction (p = 0.033).

Conclusions

Serum lipid profile has modest effects on disease progression in MS. Worsening disability is associated with higher levels of LDL, total cholesterol and triglycerides. Higher HDL is associated with lower levels of acute inflammatory activity.

Longitudinal changes in magnetisation transfer ratio in secondary progressive multiple sclerosis: data from a randomised placebo controlled trial of lamotrigine

Sodium blockade with lamotrigine is neuroprotective in animal models of central nervous system demyelination. This study evaluated the effect of lamotrigine on magnetisation transfer ratio (MTR), a putative magnetic resonance imaging measure of intact brain tissue, in a group of subjects with secondary progressive multiple sclerosis (MS). In addition, the utility of MTR measures for detecting change in clinically relevant pathology was evaluated. One hundred seventeen people attending the National Hospital for Neurology and Neurosurgery or the Royal Free Hospital, London, UK, were recruited into a double-blind, parallel-group trial. Subjects were randomly assigned by minimisation to receive lamotrigine (target dose 400 mg/day) or placebo for 2 years. Treating and assessing physicians and patients were masked to treatment allocation. Results of the primary endpoint, central cerebral volume, have been published elsewhere. Significant differences between the verum and placebo arms were seen in only two measures [normal appearing grey matter (NAGM) p = 0.036 and lesion peak height (PH) p = 0.004], and in both cases there was a greater reduction in MTR in the verum arm. Significant correlations were found of change in MS functional composite with all MTR measures except lesion and normal appearing white matter (NAWM) PH. However, the change in MTR measures over 2 years were small, with only NAGM mean (p = 0.001), lesion peak location (p = 0.11) and mean (p < 0.0001) changing significantly from baseline. These data did not show that lamotrigine was neuroprotective. The clinical correlation of MTR measures was consistent, but the responsiveness to change was limited.

Progressive multiple sclerosis and gray matter pathology: an MRI perspective

The evidence suggesting a role of extensive cortical demyelization and atrophy in progressive multiple sclerosis is rapidly increasing. Although conventional magnetic resonance imaging has had a huge impact on multiple sclerosis by enabling an earlier diagnosis, and by providing surrogate markers for monitoring disease response to anti-inflammatory/immunomodulatory treatments, it is limited by the low pathological specificity and the low sensitivity to both diffuse damage in normal-appearing white matter and focal and diffuse damage in gray matter. Advanced magnetic resonance imaging techniques can partially overcome these limitations by providing markers more specific to the underlying pathologic substrates and more sensitive to the structural and functional "occult" brain tissue damage in patients with multiple sclerosis. This review describes brain and spinal cord imaging studies of multiple sclerosis with particular emphasis on gray matter imaging in both secondary progressive and primary progressive multiple sclerosis, discusses the clinical implications of gray matter damage, and outlines current magnetic resonance imaging developments at high and ultrahigh magnetic field strength.

Advanced MRI in multiple sclerosis: current status and future challenges

MRI has rapidly become a leading research tool in the study of multiple sclerosis (MS). Conventional imaging is useful in diagnosis and management of the inflammatory stages of MS but has limitations in describing the degree of tissue injury and cause of progressive disability seen in later stages. Advanced MRI techniques hold promise for filling this void. These imaging tools hold great promise to increase understanding of MS pathogenesis and provide greater insight into the efficacy of new MS therapies.

A one-year prospective, randomized, placebo-controlled, quadruple-blinded, phase II safety pilot trial of combination therapy with interferon beta-1a and mycophenolate mofetil in early relapsing-remitting multiple sclerosis (TIME MS)

BACKGROUND

Mycophenolate mofetil (MMF) is an oral DNA base synthesis inhibitor with immunomodulatory effects on B cells, T cells, and macrophages.

OBJECTIVE

To conduct a safety and tolerability pilot study of interferon beta-1a (IFN-b1a) in combination with either placebo or oral MMF in multiple sclerosis (MS).

METHODS

Twenty-four treatment-naïve R-RMS patients participated in a one-year prospective, placebo-controlled, blinded, safety pilot clinical trial. Every patient injected weekly intramuscular interferon beta-1a. The cohort was then randomized (1 : 1) to either active oral MMF or identical-appearing placebo tablets. Clinical evaluations were assessed every 3 months, along with brain MRI scans performed at baseline and repeated every 60 days for one year. Comprehensive laboratory assessments were monitored for safety, along with adverse events.

RESULTS

In this small pilot investigation, no differences were identified between the two treatment groups with respect to patient-reported adverse events, MRI metrics, or laboratory abnormalities. Notwithstanding these observations, and the limited number of patients treated, trends appeared to favor the combination therapy regimen.

CONCLUSIONS

The combination treatment regimen of interferon beta-1a and MMF appeared to be well tolerated in this pilot study. Despite the small sample size, therapeutic trends were observed in favor of combination therapy. An adequately powered controlled trial of MMF in MS appears warranted.

Cyclophosphamide in multiple sclerosis: scientific rationale, history and novel treatment paradigms

For patients with relapsing-remitting multiple sclerosis (RRMS), there are currently six approved medications that have been shown to alter the natural course of the disease. The approved medications include three beta interferon formulations, glatiramer acetate, natalizumab and mitoxantrone. Treating aggressive forms of RRMS and progressive disease forms of MS still presents a great challenge to neurologists. Intense immunosuppression has long been thought to be the only feasible therapeutic option. In patients with progressive forms of MS, lymphoid tissues have been detected in the central nervous system (CNS) that may play a critical role in perpetuating local inflammation. Agents that are currently approved for patients with MS have no or very limited bioavailability in the brain and spinal cord. In contrast, cyclophosphamide (CYC), an alkylating agent, penetrates the blood-brain barrier and CNS parenchyma well. However, while CYC has been used in clinical trials and off-label in clinical practice in patients with MS for over three decades, data on its efficacy in very heterogeneous groups of study patients have been conflicting. New myeloablative treatment paradigms with CYC may provide a therapeutic option in patients that do not respond to other agents. In this article we review the scientific rationale that led to the initial clinical trials with CYC. We will also outline the safety, tolerability and efficacy of CYC and provide neurologists with guidelines for its use in patients with MS and other inflammatory disorders of the CNS, including neuromyelitis optica (NMO). Finally, an outlook into relatively novel treatment approaches is provided.

Grey matter volume in a large cohort of MS patients: relation to MRI parameters and disability

BACKGROUND

Although grey matter damage in multiple sclerosis is currently recognized, determinants of grey matter volume and its relationship with disability are not yet clear.

OBJECTIVES

The objectives of the study were to measure grey and white matter volumes across different disease phenotypes; identify MRI parameters associated with grey matter volume; and study grey and white matter volume as explanatory variables for clinical impairment.

METHODS

This is a cross-sectional study in which MRI data of 95 clinically isolated syndrome, 657 relapsing-remitting, 125 secondary-progressive and 50 primary-progressive multiple sclerosis patients from three centres were acquired. Grey and white matter volumes were determined, together with T2 and T1 lesion volumes. Physical disability was assessed with the Expanded Disability Status Scale, cognitive impairment with the Paced Auditory Serial Addition Task. Data were analysed using multiple regression.

RESULTS

Grey matter volume was lower in relapsing-remitting patients (mean [SD]: 0.80 [0.05] L) than in clinically isolated syndrome patients (0.82 [0.05] L), and even greater relative atrophy was found in secondary-progressive patients (0.77 [0.05] L). In contrast, white matter volume in secondary-progressive patients was comparable to that in relapsing-remitting patients. Grey matter volume was the strongest independent predictor of physical disability and cognitive impairment, and was associated with both T2 and T1 lesion volume.

CONCLUSIONS

Our findings show that grey matter volume is lower in secondary-progressive than in relapsing-remitting disease. Grey matter volume explained physical and cognitive impairment better than white matter volume, and is itself associated with T2 and T1 lesion volume.

Comparison of fingolimod with interferon beta-1a in relapsing-remitting multiple sclerosis: a randomised extension of the TRANSFORMS study

BACKGROUND

In a 12-month phase 3 study in patients with relapsing-remitting multiple sclerosis (RRMS), TRANSFORMS, fingolimod showed greater efficacy on relapse rates and MRI outcomes compared with interferon beta-1a. We had two aims in our extension: to compare year 2 with year 1 in the switched patients to assess the effect of a change from interferon beta-1a to fingolimod, and to compare over 24 months the treatment groups as originally randomised to assess the effect of delaying the start of treatment with fingolimod.

METHODS

Patients randomly assigned to receive 0.5 mg or 1.25 mg daily oral fingolimod in the core study continued with the same treatment in our extension; patients who originally received 30 μg weekly intramuscular interferon beta-1a were randomly reassigned (1:1) to receive either 0.5 mg or 1.25 mg fingolimod. The initial randomisation and dose of fingolimod assigned for the extension remained masked to the patients and investigators. As in the core study, re-randomisation was done centrally in blocks of six and stratified according to site. Our efficacy endpoints were annualised relapse rate (ARR), disability progression, and MRI outcomes. Our within-group analyses were based on the intention-to-treat and safety populations that entered our extension study. Our between-group analyses were based on the intention-to-treat and safety populations from the core study. This study is registered with ClinicalTrials.gov, number NCT00340834.

FINDINGS

1027 patients entered our extension and received the study drug, and 882 completed 24 months of treatment. Patients receiving continuous fingolimod showed persistent benefits in ARR (0.5 mg fingolimod [n=356], 0.12 [95% CI 0.08-0.17] in months 0-12 vs 0.11 [0.08-0.16] in months 13-24; 1.25 mg fingolimod [n=330], 0.15 [0.10-0.21] vs 0.11 [0.08-0.16]; however, in patients who initially received interferon beta-1a, ARR was lower after switching to fingolimod compared with the previous 12 months (interferon beta-1a to 0.5 mg fingolimod [n=167], 0.31 [95% CI 0.22-0.43] in months 0-12 vs 0.22 [0.15-0.31], in months 13-24 p=0.049; interferon beta-1a to 1.25 mg fingolimod [n=174], 0.29 [0.20-0.40] vs 0.18 [0.12-0.27], p=0.024). After switching to fingolimod, numbers of new or newly enlarging T2 and gadolinium (Gd)-enhancing T1 lesions were significantly reduced compared with the previous 12 months of interferon beta-1a therapy (p<0.0001 for T2 lesions at both doses; p=0.002 for T1 at 0.5 mg; p=0.011 for T1 at 1.25 mg), and the pattern of adverse events shifted towards that typical for fingolimod. Over 24 months, in continuous fingolimod groups compared with the group that switched from interferon beta-1a to fingolimod, we recorded lower ARRs (0.18 [95% CI 0.14-0.22] for 0.5 mg; 0.20 [0.16-0.25] for 1.25 mg; 0.33 [0.27-0.39] for the switch group; p<0.0001 for both comparisons), fewer new or newly enlarged T2 lesions (p=0.035 for 0.5 mg, p=0.068 for 1.25 mg), and fewer patients with Gd-enhancing T1 lesions (p=0.001 for 0.5 mg fingolimod vs switch group; p=0.002 for 1.25 mg fingolimod vs switch group). There was no benefit on disability progression.

INTERPRETATION

Switching from interferon beta-1a to fingolimod led to enhanced efficacy with no unexpected safety concerns. Compared with patients switched from interferon beta-1a to fingolimod, continuous treatment with fingolimod for 2 years provides a sustained treatment effect with improved clinical and MRI outcomes.

FUNDING

Novartis Pharma AG.

Fingolimod: a novel oral immunomodulatory treatment for multiple sclerosis

Fingolimod (FTY720), an immunomodulator that acts on sphingosine-1-phosphate receptors, is the first oral disease-modifying agent to be approved by the US FDA for the treatment of relapsing forms of multiple sclerosis (MS). Compared with other disease-modifying agents, fingolimod is unique in its mechanisms of action: it sequesters lymphocytes into lymph nodes without directly inhibiting effector functions, and it exerts pleiotropic actions on cultured oligodendrocytes and oligodendrocyte progenitors. Whether the latter contributes to the favorable response to this drug is currently being investigated. Results from Phase II and III clinical trials demonstrate that fingolimod is highly effective in relapsing–remitting MS. In this article, we review the background on MS therapy, the mechanisms and pharmacology of fingolimod and its benefit–risk profile as a novel therapy in MS.

A 3T MR imaging investigation of the topography of whole spinal cord atrophy in multiple sclerosis

BACKGROUND AND PURPOSE

Spinal cord atrophy is a common feature of MS. However, it is unknown which cord levels are most susceptible to atrophy. We performed whole cord imaging to identify the levels most susceptible to atrophy in patients with MS versus controls and also tested for differences among MS clinical phenotypes.

MATERIALS AND METHODS

Thirty-five patients with MS (2 with CIS, 27 with RRMS, 2 with SPMS, and 4 with PPMS phenotypes) and 27 healthy controls underwent whole cord 3T MR imaging. The spinal cord contour was segmented and assigned to bins representing each C1 to T12 vertebral level. Volumes were normalized, and group comparisons were age-adjusted.

RESULTS

There was a trend toward decreased spinal cord volume at the upper cervical levels in PPMS/SPMS versus controls. A trend toward increased spinal cord volume throughout the cervical and thoracic cord in RRMS/CIS versus controls reached statistical significance at the T10 vertebral level. A statistically significant decrease was found in spinal cord volume at the upper cervical levels in PPMS/SPMS versus RRMS/CIS.

CONCLUSIONS

Opposing pathologic factors impact spinal cord volume measures in MS. Patients with PPMS demonstrated a trend toward upper cervical cord atrophy. However patients with RRMS showed a trend toward increased volume at the cervical and thoracic levels, which most likely reflects inflammation or edema-related cord expansion. With the disease causing both expansion and contraction of the cord, the specificity of spinal cord volume measures for neuroprotective therapeutic effect may be limited.

Inflammation in neurological disorders: a help or a hindrance?

Inflammation of the central nervous system (CNS) (neuroinflammation) is now recognized to be a feature of all neurological disorders. In multiple sclerosis, there is prominent infiltration of various leukocyte subsets into the CNS. Even when there is no significant inflammatory infiltrates, such as in Parkinson or Alzheimer disease, there is intense activation of microglia with resultant elevation of many inflammatory mediators within the CNS. An extensive dataset describes neuroinflammation to have detrimental consequences, but results emerging largely over the past decade have indicated that aspects of the inflammatory response are beneficial for CNS outcomes. Benefits of neuroinflammation now include neuroprotection, the mobilization of neural precursors for repair, remyelination, and even axonal regeneration. The findings that neuroinflammation can be beneficial should not be surprising as a properly directed inflammatory response in other tissues is a natural healing process after an insult. In this article, we review the data that highlight the dual aspects of neuroinflammation in being a hindrance on the one hand but also a significant help for recovery of the CNS on the other. We consider how the inflammatory response may be beneficial or injurious, and we describe strategies to harness the beneficial aspects of neuroinflammation.

Neuroimaging in multiple sclerosis: neurotherapeutic implications

Imaging techniques, in particular magnetic resonance imaging (MRI), play an important role in the diagnosis and management of multiple sclerosis (MS) and related demyelinating diseases. Findings on MRI studies of the brain and spinal cord are critical for MS diagnosis, are used to monitor treatment response and may aid in predicting disease progression in individual patients. In addition, results of imaging studies serve as essential biomarkers in clinical trials of putative MS therapies and have led to important insights into disease pathophysiology. Although they are useful tools and provide in vivo measures of disease-related activity, there are some important limitations of MRI findings in MS, including the non-specific nature of detectable white matter changes, the poor correlation with clinical disability, the limited sensitivity and ability of standard measures of gadolinium enhancing lesions and T2 lesions to predict future clinical course, and the lack of validated biomarkers of long term outcomes. Advancements that hold promise for the future include new techniques that are sensitive to diffuse changes, the increased use of higher field scanners, measures that capture disease related changes in gray matter, and the use of combined structural and functional imaging approaches to assess the complex and evolving disease process that occurs during the course of MS.

Fingolimod for the treatment of relapsing multiple sclerosis

Fingolimod is the first oral agent approved in the USA for the treatment of relapsing forms of multiple sclerosis. Fingolimod is a sphingosine 1-phosphate receptor modulator that binds to sphingosine 1-phosphate receptors on lymphocytes, resulting in a downregulation of the receptor and a reversible sequestration of lymphocytes in lymphoid tissue. Effector memory T cells are not sequestered so that immune surveillance may be minimally affected. Two large-scale Phase III clinical trials have demonstrated the efficacy of fingolimod compared with placebo and intramuscular interferon β-1a in relapsing-remitting multiple sclerosis. Due to its mechanism of action, fingolimod administration may be associated with first-dose bradycardia and macular edema. Therefore, patients should be observed for 6 h at the time of their first dose and undergo ophthalmologic evaluation prior to treatment initiation and at 3-4 months after initiation.

A randomized controlled double-masked trial of albuterol add-on therapy in patients with multiple sclerosis

BACKGROUND

Interleukin 12 (IL-12), a cytokine that promotes generation of helper T cells subtype 1, is increased in multiple sclerosis. Albuterol sulfate, a β2-adrenergic agonist, reduces IL-12 expression, so we tested the effect of albuterol as an add-on treatment to glatiramer acetate therapy.

OBJECTIVES

To investigate the clinical and immunologic effects of albuterol treatment as an add-on therapy in patients starting glatiramer acetate treatment.

DESIGN

Single-center double-masked clinical trial.

SETTING

Academic research. Patients Subjects with relapsing-remitting multiple sclerosis.

MAIN OUTCOME MEASURES

In this single-center double-masked clinical trial, subjects with relapsing-remitting multiple sclerosis were randomized to receive a subcutaneous injection of glatiramer acetate (20 mg) plus an oral dose of placebo daily for 2 years or a subcutaneous injection of glatiramer acetate (20 mg) plus an oral dose of albuterol daily for 2 years. The primary clinical efficacy measurement was the change in Multiple Sclerosis Functional Composite at 2 years, and the primary immunologic end point was the change in expression of IL-13 and interferon γ at each study time point. The classification level of evidence from this trial is C for each question, as this is the first class II clinical trial addressing the efficacy of glatiramer acetate plus albuterol.

RESULTS

Forty-four subjects were randomized to receive glatiramer acetate plus albuterol or glatiramer acetate plus placebo, and 39 subjects contributed to the analysis. Improvement in the Multiple Sclerosis Functional Composite was observed in the glatiramer acetate plus albuterol group at the 6-month (P = .005) and 12-month (P = .04) time points but not at the 24-month time point. A delay in the time to first relapse was also observed in the glatiramer acetate plus albuterol group (P = .03). Immunologically, IL-13 and interferon-γ production decreased in both treatment groups, and a treatment effect on IL-13 production was observed at the 12-month time point (P < .05). Adverse events were generally mild, and only 3 moderate or severe events were considered related to the treatment.

CONCLUSION

Treatment with glatiramer acetate plus albuterol is well tolerated and improves clinical outcomes in patients with multiple sclerosis.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00039988.

The role of glatiramer acetate in the early treatment of multiple sclerosis

The treatment of the underlying disease process causing multiple sclerosis has continued to evolve since the initial approval of interferon-beta-1b in 1993. Current emphasis is on early treatment, including treatment after a single clinical attack (clinically isolated syndrome). The assessment of which disease modifying medication to use as initial therapy has continued to remain a combination of science and the art of medicine. Equally important are the assessment of treatment failure and the subsequent choice of medication change. This article will present scientific information, as well as information about clinical decision making, about these choices, with emphasis on the changing role of glatiramer acetate in this process.

Lamotrigine for neuroprotection in secondary progressive multiple sclerosis: a randomised, double-blind, placebo-controlled, parallel-group trial

BACKGROUND

Partial blockade of voltage-gated sodium channels is neuroprotective in experimental models of inflammatory demyelinating disease. In this phase 2 trial, we aimed to assess whether the sodium-channel blocker lamotrigine is also neuroprotective in patients with secondary progressive multiple sclerosis.

METHODS

Patients with secondary progressive multiple sclerosis who attended the National Hospital for Neurology and Neurosurgery or the Royal Free Hospital, London, UK, were eligible for inclusion in this double-blind, parallel-group trial. Patients were randomly assigned via a website by minimisation to receive lamotrigine (target dose 400 mg/day) or placebo for 2 years. Treating physicians, evaluating physicians, and patients were masked to treatment allocation. The primary outcome was the rate of change of partial (central) cerebral volume over 24 months. All patients who were randomly assigned were included in the primary analysis. This trial is registered with ClinicalTrials.gov, NCT00257855.

FINDINGS

120 patients were randomly assigned to treatment (87 women and 33 men): 61 to lamotrigine and 59 to placebo. 108 patients were analysed for the primary endpoint: 52 in the lamotrigine group and 56 in the placebo group. The mean change in partial (central) cerebral volume per year was -3.18 mL (SD -1.25) in the lamotrigine group and -2.48 mL (-0.97) in the placebo group (difference -0.71 mL, 95% CI -2.56 to 1.15; p=0.40). However, in an exploratory modelling analysis, lamotrigine treatment seemed to be associated with greater partial (central) cerebral volume loss than was placebo in the first year (p=0.04), and volume increased partially after treatment stopped (p=0.04). Lamotrigine treatment reduced the deterioration of the timed 25-foot walk (p=0.02) but did not affect other secondary clinical outcome measures. Rash and dose-related deterioration of gait and balance were experienced more by patients in the lamotrigine group than the placebo group.

INTERPRETATION

The effect of lamotrigine on cerebral volume of patients with secondary progressive multiple sclerosis did not differ from that of placebo over 24 months, but lamotrigine seemed to cause early volume loss that reversed partially on discontinuation of treatment. Future trials of neuroprotection in multiple sclerosis should include investigation of complex early volume changes in different compartments of the CNS, effects unrelated to neurodegeneration, and targeting of earlier and more inflammatory disease.

FUNDING

Multiple Sclerosis Society of Great Britain and Northern Ireland.

Role of intraspinal steroid application in patients with multiple sclerosis

Clinical trials on patients with progressive multiple sclerosis (MS) have shown no clear evidence of an effective symptomatic treatment with improving disability. Immunomodulatory compounds efficaciously reduce the relapse rate. Numerous earlier papers exist on the pros and cons and/or on the efficacy of intrathecal administration of differing dosages of various conventional released steroids. Furthermore, this treatment approach was nearly abondoned owing to a debate on side effects and a missing proven superiority over intravenous systemic high dosage steroid administration. However, recent open-label studies in progressive MS patients with predominant spinal symptomatology investigated the repeated intraspinal application of the sustained-release compound triamcinolone acetonide (TCA). A distinct improvement of walking distance and MS scores in the short term and stabilization of this beneficial effect after repeat TCA application every 6-12 weeks was found. Moreover, patients with a relapse with acute onset of painful sensations showed a marked pain improvement after repeated TCA application following prior unsuccessful treatment with intravenous steroids. The available data from open studies ask for the performance of a randomized clinical trial, comparing intravenous with intrathecal steroid administration, to confirm the higher efficacy of the more invasive therapy with repeated lumbar puncture.

Imaging outcomes for neuroprotection and repair in multiple sclerosis trials

Multiple sclerosis (MS) is commonly regarded as an inflammatory disease, but it also has a neurodegenerative component, which represents an additional target for treatment. The use of MRI to evaluate the inflammatory disease component in 'proof-of concept' clinical trials is well established, but no systematic assessment of imaging outcomes to evaluate neuroprotection or repair in MS has been performed. In this Review, we examine the potential of traditional and novel imaging parameters to serve as primary outcomes in phase II clinical trials of neuroprotective and reparative strategies in MS. We present the conclusions of an international meeting of imaging, clinical and statistical experts, as well as a review of relevant literature. The available imaging techniques are appraised in five categories of performance: pathological specificity, reproducibility, sensitivity to change, clinical relevance, and response to treatment. At present, the three most promising primary outcomes in phase II trials of neuroprotective and/or reparative strategies in MS are: changes in whole-brain volume to gauge general cerebral atrophy; T1 hypointensity and magnetization transfer ratio to monitor the evolution of lesion damage; and optical coherence tomography findings to evaluate the anterior visual pathway. Power calculations show that these outcome measures can be applied with attainable sample sizes.

Lessons from randomised direct comparative trials

For over a decade, four immunomodulatory therapies have been available for the treatment of relapsing remitting multiple sclerosis. However, few direct comparative data were available to facilitate the choice of treatment. This choice has been influenced by the perception that interferon-beta preparations have greater efficacy than glatiramer acetate, due to apparently more rapid and robust reduction of gadolinium-enhancing lesions seen on magnetic resonance imaging in the pivotal trials of these agents. This situation has changed in the last year, with the outcomes of three randomised clinical trials comparing the efficacy and safety of glatiramer acetate with that of a high-dose interferon-beta in relapsing remitting multiple sclerosis. These are the REGARD, BEYOND and BECOME trials. In the REGARD trial, 764 patients were randomised to treatment with either interferon-beta 1a sc 44 microg or glatiramer acetate for 96 weeks; no significant difference in the time to first relapse was observed. The largest of the three comparative studies, the BEYOND trial, compared treatment with interferon-beta 1b sc 500 microg, interferon-beta 1b sc 250 microg or glatiramer acetate for two years in 2,244 patients. The hazard ratio for multiple relapses was close to unity for comparisons between all groups, indicating equivalent efficacy in all three treatment arms. Relapse rates (around 0.3 relapses/year) in all these studies were much lower than anticipated and lower than those reported a decade previously in the pivotal trials of beta-interferons and glatiramer acetate. No unexpected safety issues were identified in any of these studies. The completion of these direct comparative studies has considerably enriched the clinical evidence database by contributing large numbers of patients. This provides an invaluable contribution for helping the physician make an informed choice about treatment. The results of the direct comparative studies provide evidence that glatiramer acetate and high-dose interferon-beta preparations have comparable clinical efficacy.

Current approaches to the identification and management of breakthrough disease in patients with multiple sclerosis

Disease-modifying drugs (DMDs) for relapsing-remitting multiple sclerosis (RRMS) are only partly effective -- breakthrough disease commonly occurs despite treatment. Breakthrough disease is predictive of continued disease activity and a poor prognosis. Availability of several DMDs offers the possibility of tailoring treatment to individual patients with RRMS and altering treatment in patients with breakthrough disease. However, no biological or imaging markers have been validated to guide initial treatment, markers of individual responsiveness to DMDs are scarce, and there is no class 1 evidence to guide alternative therapy in patients with breakthrough disease. In this Review, we discuss proposed strategies to monitor patients with RRMS being treated with DMDs, outline approaches to identifying therapeutic response in individual patients, review MRI and biological markers of treatment response, and summarise the role of antibodies in biological therapies. We also outline possible strategies for the management of patients with breakthrough disease and highlight areas in which research is needed.

PBMCs protein expression profile in relapsing IFN-treated multiple sclerosis: A pilot study on relation to clinical findings and brain atrophy

This cross-sectional study investigated with two-dimensional gel electrophoresis coupled to MALDI-TOF and MRI the relationship between PBMCs protein expression profile and whole-brain atrophy in 16 unselected RR-MS IFN-treated patients compared with 6 RR IFN-untreated and 12 matched healthy control subjects. Grey/white matter fraction, T1/T2 lesion load and clinical variables were considered too. Twenty six proteins showed significant differential expression among RR IFN-treated patients and control samples. Four of these (IN35, GANAB, PP1B, SEPT2) resulted correlated with clinical and MRI findings in RR IFN-treated MS patients. Future clinical applications remain to be validated by other techniques and confirmed by a larger study.

Multiple sclerosis: clinical features, pathophysiology, neuroimaging and future therapies

Multiple sclerosis (MS) is a common immune-mediated progressive neurodegenerative disease of the CNS that typically manifests with periods of disease activity followed by intervals of remission. The etiology of MS remains unknown; however, existing evidence indicates that MS is a ‘whole-brain disease’ that is driven by a potent immune response against CNS antigen(s), particularly myelin peptide antigens. The immunopathogenesis of MS includes both the cell- and humorally-mediated arms of the immune system. Genetic and environmental factors play important roles in the development of MS. Application of various neuroimaging techniques to the world of MS have expanded our knowledge concerning its pathogenesis and assist us in the more accurate diagnosis of MS versus its imitators. Current treatments target acute attacks and aim to reduce future clinical relapses. A summary of the potential future therapies for MS is presented.

Gray matter pathology in (chronic) MS: modern views on an early observation

Involvement of the gray matter (GM) in the pathology of multiple sclerosis (MS) was already recognized in the early days of MS research, but the detection of (cortical) GM lesions under the microscope and with magnetic resonance imaging (MRI) techniques was initially suboptimal and could only recently be enhanced. The visualization of GM lesions in vivo opens new doors for studies focusing on clinical, especially cognitive, effects of GM pathology, as well as for monitoring of neuroprotective treatment. However, so far little is known about what causes GM pathology. In this review, several pathogenetic mechanisms will be discussed, affecting the MS brain both from the 'outside-in' and from the 'inside-out'. Also, the use and reliability of MRI atrophy measures as a monitoring tool for GM damage in the therapeutic setting will be reviewed.

Gender-related differences in MS: a study of conventional and nonconventional MRI measures

Background

Studies showed gender-associated differences in multiple sclerosis (MS) disease evolution and in the evolution of conventional magnetic resonance imaging (MRI) findings.

Objective

The aim of this study was to investigate gender differences according to a number of conventional and nonconventional MRI measures in patients with MS.

Methods

We examined 763 consecutive patients with MS [499 (19.2% men) relapsing-remitting (RR), 230 (24.8% men) secondary-progressive, and 34 (44.1% men) primary-progressive], 32 (21.9% men) patients with clinically isolated syndrome (CIS), and 101 (30.7% men) normal controls (NC). Patients were assessed using conventional and nonconventional MRI measures. Gender-related MRI differences were investigated using general linear model analysis, corrected for MS disease type.

Results

In the total MS group, male patients showed lower normalized peripheral gray matter (GM) ( P < 0.001) and normalized GM ( P = 0.011) volumes than female patients. Female patients presented lower normalized white matter (WM) volumes ( P = 0.011). These gender effects were not observed in NC. Male patients also showed more advanced central atrophy ( P = 0.022). In RRMS male patients, there was also a higher lateral ventricle volume ( P = 0.001). The GM-WM normalized ratio was lower for male patients with MS compared with male NC (0.97 vs. 1.09, P < 0.001) but not in patients with CIS compared with NC.

Conclusions

There were no significant gender-related differences regarding nonconventional MRI measures. GM and central atrophy are more advanced in male patients, whereas WM atrophy is more advanced in female patients. These gender-related MRI differences may be explained by the effect of sex hormones on brain damage and repair mechanisms.

Neonatal high pressure hydrocephalus is associated with elevation of pro-inflammatory cytokines IL-18 and IFNgamma in cerebrospinal fluid

Background

In human neonatal high pressure hydrocephalus (HPHC), diffuse white matter injury and gliosis predispose to poor neuro-developmental outcome. The underlying mechanism for diffuse white matter damage in neonatal HPHC is still unclear. Analogous to inflammatory white matter damage after neonatal hypoxemia/ischemia, we hypothesized that pro-inflammatory cytokines could be involved in neonatal HPHC. If so, early anti-inflammatory therapy could ameliorate white matter damage in HPHC, before irreversible apoptosis has occurred. In HPHC and control neonates, we therefore aimed to compare cerebrospinal fluid (CSF) concentrations of IL18, IFNγ and sFasL (interleukin 18, interferon gamma and apoptosis marker soluble-Fas ligand, respectively).

Methods

In neonatal HPHC (n = 30) and controls (n = 15), we compared CSF concentrations of IL18, IFNγ and sFasL using sandwich ELISA. HPHC was grouped according to etiology: spina bifida aperta (n = 20), aqueduct stenosis (n = 4), and fetal intra-cerebral haemorrhage (n = 6). Neonatal control CSF was derived from otherwise healthy neonates (n = 15), who underwent lumbar puncture for exclusion of meningitis.

Results

In all three HPHC groups, CSF IL18 concentrations were significantly higher than control values, and the fetal intracranial haemorrhage group was significantly higher than SBA group. Similarly, in all HPHC groups CSF-IFNγ concentrations significantly exceeded the control group. In both HPHC and control neonates, CSF FasL concentrations remained within the range of reference values.

Conclusion

Independent of the pathogenesis, neonatal HPHC is associated with the activation of the pro-inflammatory cytokines (IL-18 and IFNγ) in the CSF, whereas CSF apoptosis biomarkers (sFasL) were unchanged. This suggests that anti-inflammatory treatment (in addition to shunting) could be helpful to preserve cerebral white matter.

Interferon-beta treatment for relapsing multiple sclerosis

BACKGROUND

Recombinant forms of IFN-beta were the first therapeutic intervention found to be effective at interfering with the course of multiple sclerosis (MS), a chronic and debilitating disease affecting the CNS in young adults.

OBJECTIVE/METHODS

To examine the application of IFN-beta to MS treatment by a review of relevant literature.

RESULTS

The different IFN-beta products available are similar in their clinical effects. However, the response to IFN-beta therapy is only partial and the most efficient individual-specific dose, route and frequency of administration are not elucidated fully. The mechanism of action of IFN-beta in MS is also not understood fully but its immunomodulatory effects are probably more important than its anti-proliferative and antiviral activities.

CONCLUSIONS

Although new therapeutic approaches are being sought to better treat MS, IFN-beta remains one of the most recognized and approved worldwide therapeutic options for this disease.