Dimethyl fumarate in the treatment of relapsing–remitting multiple sclerosis: an overview

Multiple sclerosis (MS) shares an immune-mediated origin with psoriasis. Long-term safety and efficacy data generated in Europe from usage of fumaric acid formulations in the latter disease constituted grounds to investigate their effects in MS patients. Dimethyl fumarate (DMF) was found to be the active principle in those formulations and in vitro studies have demonstrated that DMF has immune-modulatory properties exerted through abilities to divert cytokine production toward a Th2 profile, both on lymphocytes and microglial cells. More importantly, DMF was discovered to impact the anti-oxidative stress cell machinery promoting the transcription of genes downstream to the activation of the nuclear factor (erythroid derived 2)-like2 (NRF2). DMF exposure increases the cytosol concentrations of NRF2, which besides immune regulatory effects, has the potential for cytoprotection on glial cells, oligodendrocytes and neurons. Extensive and rigorous clinical trials have assessed the efficacy and safety of DMF at the dose of 240 mg twice and three times a day in relapsing-remitting MS patients during one phase IIb and two phase III trials. Robust, positive results were obtained across a number of clinical and paraclinical parameters. In one study (DEFINE), the relative reductions of the adjusted annualized relapse rate of the low and high dose regimens in comparison with placebo were 53% and 48%, respectively ( p  < 0.001 for both comparisons). In the other trial (CONFIRM), DMF decreased the annualized relapse rate in comparison with placebo by 44% in the lower and by 51% in higher dosage group (also p < 0.001). The number and size of lesions as detected by magnetic resonance imaging were also significantly decreased in comparison with the patients receiving DMF at every dosage. Multiple post hoc and subgroup analyses corroborated the clinical data, rendering DMF an appealing medication whose potential for impacting the degenerative aspects of MS remains to be explored

Extended interval dosing of natalizumab: a two-center, 7-year experience

Background: The enthusiasm for natalizumab, a highly efficacious agent in the treatment of multiple sclerosis (MS), has been tempered by the risks of progressive multifocal leukoencephalopathy associated with its use, and strategies to minimize those risks are of great interest. Extended interval dosing (EID) has been proposed as a way to maintain the efficacy of natalizumab while reducing exposure to it. We reviewed a cohort of patients who received natalizumab at 6–8-week intervals instead of the typical infusions every 4 weeks with the goal to assess if patients on EID had an increase in clinical relapses. Methods: This is a retrospective review of all patients with MS treated with natalizumab at two MS centers where patients were offered the opportunity to switch to an EID every 6 or 8 weeks. Results: A total of 361 patients received natalizumab for 22 ± 13 months (minimum duration 6 months). Of these, 96 patients received EID natalizumab at some point for 20 ± 11 months (minimum duration 6 months). Over the study period, there was no significant difference between the relapse rate in the monthly dosing (13%) and the EID (13%) groups of patients. Conclusion: Natalizumab is effective in controlling MS as very few clinical relapses were observed in our dataset. We found that EID did not compromise the treatment effect as measured by relapse rate and no significant breakthrough disease activity was observed. EID is an optional regimen for maintenance natalizumab therapy, but prospective studies are warranted to determine its efficacy

Head Tremor Secondary to MS Resolved With Rituximab

We describe the case of a 33-year-old woman who presented with a 2-month history of worsening head tremor. The medical evaluation led to the new diagnosis of MS and the MRI of brain demonstrated prominently active disease. Intravenous rituximab was started according to the HERMES trial, and significant improvement was noted. She has received additional rituximab dosing approximately every 6 months, and at the 2-year follow-up the tremor has not recurred. The resolution of head tremor likely resulted from the complete suppression of MS disease activity, which must have allowed restoration of normal neural circuitry. In agreement with a growing body of evidence that supports early control of MS disease activity to prevent accumulation of fixed disability, this case advocates for aggressive immunological therapy at the onset of tremor in MS patients

Cervical spondylosis is a risk factor for localized spinal cord lesions in multiple sclerosis

OBJECTIVES: To answer the question whether cervical spondylosis would increase the incidence of cord lesions in MS patients, we investigated the statistical association between the two pathologies. METHODS: We extracted demographics, basic disease characteristics and MRI data of a cohort of 304 consecutive MS patients. For a subset of 176 patients, a detailed analysis independently assessed for each cervical level the co-existence of spinal canal narrowing from spondylosis and corresponding cord signal abnormalities. RESULTS: The cohort had typical demographics and in over 80 % of cases there was at least one cord lesion. EDSS correlated with age, disease duration, cerebral lesion burden and spinal cord lesions. After adjusting for either age, disease duration, central lesion burden, or EDSS, the presence of spinal spondylosis was not significantly associated with spinal cord lesions (p \u3e 0.05). In the subset of 176 subjects with the level-by-level spine data, we found a highly statistically significant association (Pearson\u27s chi(2) = 23.7, p \u3c 0.001) between canal narrowing and cord lesion at the level directly above or below. This association remained highly significant in both univariable and multivariable logistic regression models adjusting for age, disease duration, MS treatment, cerebral lesion burden and disability scores (p \u3c 0.001). CONCLUSIONS: The data from our cohort of MS patients suggest an indirect contribution of cervical spondylosis to disability by increasing the risk of developing localized cord lesions. While further studies are needed to confirm the findings and clarify disease mechanisms, closer attention should be paid to worsening spondylosis in patients with MS

Interleukin-10 Producing-B Cells and Their Association With Responsiveness to Rituximab in Myasthenia Gravis

Introduction: A subset of regulatory B cells in humans and mice has been defined functionally by their ability to produce interleukin (IL)-10. We characterized IL-10-producing B (B10) cells in myasthenia gravis (MG) patients and correlated them with disease activity and responsiveness to rituximab therapy. Methods: Frequencies of B10 cells from MG patients and healthy controls were monitored by fluorescence-activated cell sorting (FACS). Results: MG patients had fewer B10 cells than controls, which was associated with more severe disease status. Moreover, patients who responded well to rituximab therapy exhibited rapid repopulation of B10 cells, whereas in patients who did not respond well to rituximab, B10 cell repopulation was delayed. The kinetics of B10 cells were related to the responsiveness to rituximab in MG. Conclusions: We have characterized a specific subset of B10 cells in MG patients which may serve as a marker for disease activity and responsiveness to immune therapy

Interleukin-10 Producing-B Cells And Their Association With Responsiveness To Rituximab In Myasthenia Gravis

Introduction: A subset of regulatory B cells in humans and mice has been defined functionally by their ability to produce interleukin (IL)-10. We characterized IL-10-producing B (B10) cells in myasthenia gravis (MG) patients and correlated them with disease activity and responsiveness to rituximab therapy. Methods: Frequencies of B10 cells from MG patients and healthy controls were monitored by fluorescence-activated cell sorting (FACS). Results: MG patients had fewer B10 cells than controls, which was associated with more severe disease status. Moreover, patients who responded well to rituximab therapy exhibited rapid repopulation of B10 cells, whereas in patients who did not respond well to rituximab, B10 cell repopulation was delayed. The kinetics of B10 cells were related to the responsiveness to rituximab in MG. Conclusions: We have characterized a specific subset of B10 cells in MG patients which may serve as a marker for disease activity and responsiveness to immune therapy. © 2013 Wiley Periodicals, Inc. Published 2013 by Wiley Periodicals, Inc. This article is a US Government work and, as such, is in the public domain in the United States of America

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