Therapy of relapsing multiple sclerosis. Treatment approaches for nonresponders

Safety of long-term intrathecal methotrexate in progressive forms of MS

Background

There are few treatment options for multiple sclerosis (MS) patients with advanced disability [expanded disability status scale (EDSS) ⩾ 6.0]. In 2010, we reported initial results of using intrathecal methotrexate (ITMTX) in patients with progressive MS. We now report on long-term use of ITMTX. We performed a retrospective chart analysis of patients who have had 18 or more treatments to establish the ongoing safety and tolerability of ITMTX. Thus, the objective of this study was to establish the safety and tolerability of long-term therapy with (ITMTX) in patients with treatment-resistant, progressive forms of MS.

Methods

We studied 83 patients (67 secondary and 16 primary progressive) who received ITMTX 12.5 mg every 8-11 weeks for 3-10 years (range: 18-57 treatments). All patients were evaluated neurologically, and their EDSS was assessed at every treatment. In addition, all adverse events, frequency of infections, and any hospitalizations, were noted.

Results

There were no deaths, hospitalizations, or other serious adverse effects related to ITMTX. Headaches occurred at least once in 12% of patients, and transient fatigue occurred in 53% of patients. As determined by EDSS, there was no significant change from baseline status to post-treatment scores in both primary progressive MS (PPMS) and secondary progressive (SPMS) patients.

Conclusions

Pulsed ITMTX was well tolerated for up to 10 years in PPMS patients with no serious adverse effects. Although this was an open-label, retrospective analysis, and efficacy could not be studied, there was evidence of disease stabilization in many patients receiving ITMTX. It appears that long-term ITMTX is a safe therapeutic option in advanced progressive MS.

Influence of APOE gene polymorphisms on interferon-beta treatment response in multiple sclerosis

OBJECTIVE

Clinical trials with interferon beta in relapsing remitting multiple sclerosis (RRMS) have demonstrated a reduction in the relapse rate. Nevertheless, not all patients respond to this treatment, although there is no consensus regarding the definition of response to therapy. The reasons for this failure are not known but genetic factors probably influence this, as has been previously shown with Interleukin 10 or Interferon gamma polymorphisms. The role of apolipoprotein E (APOE) gene in MS has been investigated and does not appear to increase risk for MS or influence disease severity. Interestingly APOE variation influences response to cholinesterase inhibitor treatment in Alzheimer disease or to statins in hypercholesterolemia. This might have future implications for MS.

MATERIAL AND METHODS

We retrospectively reviewed 38 RRMS patients (32 females and 6 males) treated with interferon beta (INFbeta) over at least two years. Criteria for treatment were uniform accordingly to an "Advisory Committee for the Treatment of Multiple Sclerosis". We collected data variables including age, age of onset, clinical type or disease duration. Patients were classified, two years after the start of treatment, as responders and non-responders based upon clinical criteria available in the literature, which rely on the presence of relapses, increase of disability, or both. APOE genotype was determined from blood samples using validated polymerase chain reaction methods. Correlation between patient responding status with allele E2 or E4 was tested.

RESULTS

A total of 20 patients (52.6%) received subcutaneous INFbeta1b (Betaferón(®)), 13 (34.2%) INFbeta1a intramuscular (Avonex(®)), and 5 (13.2%) subcutaneous INFbeta1a (Rebif(®)). We found 2 patients (5.2%) heterozygous for the E2 allele and 9 (23.7%) for the E4 allele. No patient was homozygous for E2 or E4. Comparison of patients with and without E2 or E4 allele showed no significant differences in any of the ten therapy response variables assessed.

CONCLUSION

Findings of a recent meta-analysis have not supported a role for APOE in MS susceptibility or severity. We have not found, in our data, any influence of this gene in the RRMS response to INFbeta. However, larger series would be required to validate these results.

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.

Liver X receptor and retinoid X receptor agonists inhibit inflammatory responses of microglia and astrocytes

Liver X receptors (LXRs) are nuclear receptors previously identified to be important in lipid metabolism. Recent reports suggest that LXR agonists also exhibit anti-inflammatory properties in mouse models of atherosclerosis and contact dermatitis. In the present study, we investigated the effects of LXR agonists on mouse microglia and astrocytes. When chronically activated, these resident-CNS glia have been implicated in the pathology of neuroinflammatory disorders including multiple sclerosis (MS). Our studies demonstrated for the first time that LXR agonists inhibited the production of nitric oxide, the pro-inflammatory cytokines IL-1beta and IL-6 and the chemokine MCP-1 from LPS-stimulated microglia and astrocytes. Furthermore, LXR agonists inhibited LPS-induction of nuclear factor-kappa B (NF-kappaB) DNA-binding activity. These agonists also blocked LPS-induction of IkappaB-alpha protein degradation in microglia, suggesting a mechanism by which these agonists modulate NF-kappaB DNA-binding activity. These studies suggest that LXR agonists suppress the production of pro-inflammatory molecules by CNS glia, at least in part, by modulating NF-kappaB-signaling pathways. Retinoid X receptors (RXRs) physically interact with LXR receptors, and the resulting obligate heterodimer regulates the expression of LXR-responsive genes. Interestingly, a combination of LXR and RXR agonists additively suppressed the production of NO by microglia and astrocytes. Collectively, these studies suggest that LXR agonists may be effective in the treatment of neuroinflammatory diseases including MS.

Immunomodulatory effects of 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitors, potential therapy for relapsing remitting multiple sclerosis

This study characterized immunomodulatory targets of statins in humans and their potential for treatment of relapsing remitting multiple sclerosis (RR MS). Statins inhibited the proliferative response of mononuclear cells. Simvastatin, the statin with the strongest antiproliferative effect, inhibited IFN-gamma-induced expression of MHC class II DR on monocytes and decreased their antigen presenting capacity. As for T lymphocytes, it inhibited their activation and expression of the Th1 lineage differentiation markers. Simvastatin inhibited IFN-gamma, TNF-alpha, and IL-2 secretion, as well as the expression of T-bet, a transcription factor that regulates Th1 cell differentiation.

HLA class II and response to interferon-beta in multiple sclerosis

OBJECTIVE

To study the relationship between human leucocyte antigen (HLA) genotype and clinical response to interferon-beta (IFN-beta).

METHODS

We analysed the HLA class II genotypes of 96 multiple sclerosis (MS) patients treated with IFN-beta. The patients were classified as responders or non-responders according to clinical criteria: one or more relapses or a sustained increase after 1 year treatment compared with the year prior to IFN-beta therapy of > or = 0.5 points on the Expanded Disability Status Scale (EDSS).

RESULTS

There were 66 (69%) responders and 30 (31%) non-responders. Baseline clinical characteristics were similar. We found no association between HLA class II alleles and clinical response to IFN-beta.

CONCLUSIONS

HLA genotype does not appear to influence the clinical response to IFN-beta in MS patients.

Mitoxantrone as rescue therapy in worsening relapsing-remitting MS patients receiving IFN-beta

We assessed the action of mitoxantrone (MX) when given as rescue therapy in patients with relapsing-remitting (RR) multiple sclerosis (MS), whose disease activity worsens despite IFN-beta treatment. Ten very active RR MS patients received MX 12 mg/m2 monthly, for 3 months, and then returned to the original treatment with IFN-beta. Following treatment with MX, 70% of patients were able to return to IFN-beta treatment, stabilising EDSS and relapse rate during a follow-up period of 15-18 additional months. In contrast, in 30% of the patients who were taken off MX and returned to IFN-beta treatment the EDSS score deteriorated and the number of exacerbations increased significantly. The latter patients were switched again to MX treatment at 3-month intervals, stabilising EDSS and relapse rate during 15-18 additional months. Clinical findings correlated with the number of Gd-enhancing lesions disclosed in MRI scans. Immunological data were consistent with the clinical and MRI benefits observed. We conclude that brief courses of MX may provide a safe treatment alternative for RR MS patients who experience rapid and severe worsening of their disease despite IFN-beta treatment.

Optimization of the safety and efficacy of interferon beta 1b and azathioprine combination therapy in multiple sclerosis

We conducted an open-label pilot clinical trial to evaluate the safety and efficacy of adding oral azathioprine to the treatment regimen of 15 multiple sclerosis patients breaking through monotherapy with interferon beta-1b. There were no serious adverse events. Gastrointestinal side effects and leukopenia were the most common adverse events and limited dose escalation. There was a 65% reduction in the number of gadolinium-enhanced magnetic resonance imaging (MRI) lesions on combination therapy compared to the baseline values (P =0.003). A total WBC count less than 4800/mm3 was the best predictor of MRI response.

The expression of apoptosis-regulatory proteins in B lymphocytes from patients with multiple sclerosis

The pathogenesis of multiple sclerosis (MS) is thought to involve T- and B-lymphocyte-mediated autoimmunity. However, the mechanisms that regulate lymphocyte activity in MS are poorly understood. In normal circumstances, programmed cell death (apoptosis) contributes to the maintenance of lymphocytes homeostasis and the deletion of autoreactive cells. Cellular commitment to apoptosis is partly regulated by the cell death receptor Fas, and the anti-apoptosis proteins Bcl-2 and FLIP. Although there is emerging evidence that dysregulations of apoptotic pathways play a role in T-cell autoimmunity in MS, the expression of apoptosis-regulatory proteins in B cells from MS patients is largely unknown. In this study, we analyzed the expression profiles of Fas, Bcl-2, and FLIP proteins in peripheral B lymphocytes from patients with relapsing-remitting and progressive MS, and from appropriate controls. We observed a significant up-regulation of Bcl-2 and FLIP proteins in B cells from relapsing-remitting MS when compared to corresponding expression in progressive MS, or in noninflammatory neurologic controls and healthy individuals. This cellular overexpression of Bcl-2 and FLIP proteins was not affected by treatment with interferon-beta, but was also observed in B cells from patients with systemic inflammatory diseases. Our findings suggest that cellular overexpression of the apoptosis-inhibitory proteins in patients with relapsing MS may promote apoptotic resistance of potentially pathogenic, autoreactive B lymphocytes and consequently, may allow for continuing autoimmune tissue destruction.

Reduced expression of the inhibitor of apoptosis proteins in T cells from patients with multiple sclerosis following interferon-beta therapy

Treatment with interferon-beta reduces clinical exacerbations in multiple sclerosis (MS) through several immunomodulatory mechanisms that involve the augmentation of programmed cell death (apoptosis) of peripheral T lymphocytes. The recently identified family of inhibitor of apoptosis (IAP) proteins is a potent regulator of cell death. The expression of IAP-1, IAP-2, and X-linked IAP (XIAP) is upregulated in mitogen stimulated T lymphocytes from MS patients, and this expression correlates with MS disease activity. In this study, we sought to evaluate the effect of interferon-beta on cellular expression of IAP proteins and other apoptosis regulatory molecules. In a prospective study, we evaluated the expression of IAP proteins, the anti-apoptosis Bcl-2 protein, and the death receptor Fas in in vitro stimulated T lymphocytes from MS patients, before and serially after treatment with interferon-beta. We also investigated the long-term effects of interferon-beta on cellular expression of these proteins and T lymphocyte apoptosis in a cross-sectional study of MS patients receiving drug therapy for a mean of 4.8 years. Treatment with interferon-beta reduced the expression of IAP-1, IAP-2 and XIAP in stimulated T lymphocytes. This reduced expression correlated with increased T cell susceptibility to apoptosis and with clinical response to treatment. In contrast, interferon-beta therapy did not alter cellular expression of Bcl-2 protein or the death receptor Fas. This downregulatory effect of interferon-beta on cellular expression of IAP proteins was maintained following long-term therapy. Our findings suggest that interferon-beta therapy exerts a regulatory effect on peripheral T lymphocytes through an anti-apoptosis mechanism that involves the downregulation of cellular IAP proteins expression.

An open-label trial of combination therapy with interferon beta-1a and oral methotrexate in MS

An open-label study was performed to evaluate the safety and efficacy of combination therapy with weekly oral methotrexate (20 mg) and interferon beta-1a (IFN beta-1a) in 15 patients with MS who had experienced exacerbations while receiving IFN beta monotherapy. Nausea was the only major side effect. A 44% reduction in the number of gadolinium-enhanced lesions seen on MRI scan was observed during combination therapy (p = 0.02). There was a trend toward fewer exacerbations. This combination therapy appears to be safe and well tolerated, and should be studied in a controlled trial.

Management of optic neuritis and multiple sclerosis

Optic neuritis and multiple sclerosis (MS) are common causes of visual and neurologic dysfunction in young adults. Advances in magnetic resonance imaging, molecular genetics, and neuroimmunology have increased our understanding of the pathophysiology underlying both disorders. Corticosteroids remain the mainstay of treatment of optic neuritis, but alternate dosages and routes of administration are undergoing investigation. The available therapies for MS have expanded, and there is evidence that early intervention is beneficial. Treatments for MS show sustained efficacy, but are not curative, and adjunctive treatments may prove valuable in patients with progressive visual and neurologic disability.

Interferon-beta therapy downregulates the anti-apoptosis protein FLIP in T cells from patients with multiple sclerosis

Interferon-beta reduces clinical exacerbations in multiple sclerosis (MS) through several immunomodulatory mechanisms that may involve augmentation of programmed cell death (apoptosis) of T lymphocytes. The anti-apoptosis protein FLIP (Fas-associated death domain-like interleukin-1beta-converting enzyme inhibitory protein) has been recently identified as a potent regulator of T lymphocyte susceptibility to apoptosis. In a prospective study, we evaluated the expression of FLIP and other apoptosis regulatory proteins in ex vivo activated T lymphocytes from MS patients, before and serially after treatment with interferon-beta. We also investigated the long-term effects of interferon-beta on T cell apoptosis in a cross-sectional study of MS patients receiving chronic drug therapy. Treatment with interferon-beta reduced the expression of FLIP isoforms in activated T lymphocytes. This reduced expression correlated with augmented T cell susceptibility to apoptosis and with clinical response to treatment. In contrast, interferon-beta therapy did not alter cellular expression of the anti-apoptotic protein Bcl-2. This downregulatory effect of interferon-beta on cellular FLIP expression was maintained following long-term therapy. Our findings suggest that interferon-beta therapy exerts a regulatory effect on peripheral T lymphocytes through a pro-apoptosis mechanism that involves the downregulation of cellular FLIP expression.

Diagnostic features of pemphigus vulgaris in patients with pemphigus foliaceus: detection of both autoantibodies, long-term follow-up and treatment responses

There are several studies that describe the simultaneous presence and conversion of pemphigus foliaceus into pemphigus vulgaris and vice versa. We describe eight patients with clinical, histological and immunopathological features of pemphigus foliaceus, at the time of the initial diagnosis. After a mean period of 2.5 years, additional serological features of pemphigus vulgaris were observed. During a long-term follow-up, systemic therapies, their durations and treatment outcomes were recorded. These patients did not respond to conventional systemic therapy and developed multiple side-effects from these drugs. Hence, they were treated with intravenous immunoglobulin therapy (IVIg). Prior to the initiation of IVIg therapy, different assays were performed to detect the presence of autoantibodies, including indirect immunofluorescence (IIF), immunoblot assay using bovine gingival lysate, and ELISA. Twenty-five healthy normal individuals, 12 patients with pemphigus vulgaris, and eight patients with pemphigus foliaceus served as controls for comparison of serological studies. At the time of initial diagnosis, the sera of all eight study patients also demonstrated binding on an immunoblot assay to a 160-kDa protein (desmoglein 1) only. This is typically observed in pemphigus foliaceus. Prior to staring IVIg therapy, binding was observed to both the 160 kDa and 130 kDa (desmoglein 3) proteins on an immunoblot assay which was characteristic of pemphigus vulgaris. The antidesmogleins, 1 and 3 autoantibodies, were predominantly of the IgG4 subclass in all eight patients studied. IVIg therapy induced remission in four patients and control in four of the eight patients. The total follow-up period ranged from 2.6 to 9.5 years (mean 5.3 years). It is difficult to determine the exact time at which these patients with pemphigus foliaceus developed pemphigus vulgaris. It is possible that the disease was nonresponsive to conventional immunosuppressive therapy owing to the simultaneous presence of two autoantibodies.

Simultaneous presence of mucous membrane pemphigoid and pemphigus vulgaris: molecular characterization of both autoantibodies

There are several reports in the literature describing the coexistence of features of pemphigus vulgaris and pemphigoid in the same patient. We describe 15 patients with clinical, histological, and immunopathological features of mucous membrane (cicatricial) pemphigoid at the time of initial diagnosis. All 15 patients failed to respond clinically to conventional systemic agents over a mean period of 7.2 years. Hence, IVIg therapy was used. Prior to initiating IVIg therapy, features of mucous membrane pemphigoid and pemphigus vulgaris were demonstrated by various serological tests. Different assays were performed to identify molecular characteristics of these two autoantibodies. Twenty-five healthy normal individuals, 22 patients with mucous membrane pemphigoid, 17 patients with pemphigus vulgaris, and 12 patients with pemphigus foliaceus served as controls for comparison of serological studies. On indirect immunofluorescence, using monkey esophagous as substrate, sera of all 15 patients had demonstrable levels of anti-intercellular cement substance (ICS) or anti-keratinocyte cell surface antibody. Sera of 14 patients on salt split skin bound to the epidermal side of the split, which was consistent with mucous membrane pemphigoid. Sera of all 15 patients demonstrated binding to a 205-kDa protein (human B4 integrin) and a 130-kDa protein (desmoglein 3) on immunoblot. In a sample of sera from each of the 6 patients with mucous membrane pemphigoid and pemphigus vulgaris, the anti-ICS antibody was of the IgG4 subclass. The IgG4 subclass is a characteristic feature associated with pathogenic autoantibodies in pemphigus vulgaris. Hence, in such patients, a dual diagnosis should be considered and confirmed by various serological assays. It is possible that the presence of two pathogenic autoantibodies in these patients could have contributed to the lack of response to conventional immunosuppressive therapy.