Oral treatment for multiple sclerosis

Selected transient receptor potential channel genes' expression in peripheral blood mononuclear cells of multiple sclerosis

Transient receptor potential channels have responsibilities in many cellular processes such as cytokine production, cell differentiation, and cytotoxicity by affecting intracellular cation levels or intracellular signal pathways. Multiple sclerosis is a chronic autoimmune central nervous system (CNS) disease caused by environmental and genetic factors. In this study, we aim to investigate TRPV1-TRPV4, TRPM2, TRPM4, TRPM7, TRPC6, and TRPA1 mRNA expression levels, which are associated with the inflammatory process, in the peripheral blood mononuclear cells (PBMCs) of relapsing-remitting multiple sclerosis (RRMS) patients. Thirty-five healthy controls and age-gender matched thirty patients with RRMS were involved in the study. TRPC6, TRPA1, TRPM2, TRPM4, TRPM7, TRPV1, TRPV2, TRPV3, and TRPV4 PBMCs mRNA expression levels were determined by qPCR. In the present study, the TRPC6, TRPM7, TRPV1, TRPV3, and TRPV4 mRNA expressions of RRMS patients in PBMCs decreased at a significant level compared to the healthy control group (p = .000, p = .000, p = .044, p = .000, p = .004, respectively). The decreased expression of TRPC6, TRPM7, TRPV1, TRPV3, and TRPV4 in PBMCs may be associated with the pathogenesis of MS. Further studies are required to understand the mechanism of the relation between these TRP channels and MS and other autoimmune diseases.

Dimethyl fumarate protects thioacetamide-induced liver damage in rats: Studies on Nrf2, NLRP3, and NF-κB

The present study was designed to investigate the hepatoprotective potential of dimethyl fumarate (DMF) against thioacetamide (TAA)-induced liver damage. Wistar rats were treated with DMF (12.5, 25, and 50 mg/kg/day, orally) and TAA (200 mg/kg intraperitoneally, every third day) for 6 consecutive weeks. TAA exposure significantly reduced body weight, increased liver weight and index, and intervention with DMF did not ameliorate these parameters. DMF treatment significantly restored TAA-induced increase in the levels of aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transferase, total bilirubin, uric acid, malondialdehyde, reduced glutathione, and histopathological findings such as inflammatory cell infiltration, deposition of collagen, necrosis, and bridging fibrosis. DMF treatment significantly ameliorated TAA-induced hepatic stellate cell activation, increase in inflammatory cascade markers (NACHT, LRR, and PYD domains-containing protein 3; NLRP3, apoptosis-associated speck like protein containing a caspase recruitment domain; ASC, caspase-1, nuclear factor-kappa B; NF-κB, interleukin-6), fibrogenic makers (α-smooth muscle actin; ɑ-SMA, transforming growth factor; TGF-β1, fibronectin, collagen 1) and antioxidant markers (nuclear factor (erythroid-derived 2)-like factor 2; Nrf2, superoxide dismutase-1; SOD-1, catalase). The present findings concluded that DMF protects against TAA-induced hepatic damage mediated through the downregulation of inflammatory cascades and upregulation of antioxidant status.

Advances in oral immunomodulating therapies in relapsing multiple sclerosis

BACKGROUND

Oral treatment options for disease-modifying therapy in relapsing multiple sclerosis have substantially increased over the past decade with four approved oral compounds now available: fingolimod, dimethyl fumarate, teriflunomide, and cladribine. Although these immunomodulating therapies are all orally administered, and thus convenient for patients, they have different modes of action. These distinct mechanisms of action allow better adaption of treatments according to individual comorbidities and offer different mechanisms of treatment such as inhibition of immune cell trafficking versus immune cell depletion, thereby substantially expanding the available treatment options.

RECENT DEVELOPMENTS

New sphingosine-1-phosphate receptor (S1PR) modulators with more specific S1PR target profiles and potentially better safety profiles compared with fingolimod were tested in patients with relapsing multiple sclerosis. For example, siponimod, which targets S1PR1 and S1PR5, was approved in March, 2019, by the US Food and Drug Administration for the treatment of relapsing multiple sclerosis including active secondary progressive multiple sclerosis. Ozanimod, another S1P receptor modulator in the approval stage that also targets S1PR1 and S1PR5, reduced relapse rates and MRI activity in two phase 3 trials of patients with relapsing multiple sclerosis. Blocking of matrix metalloproteinases or tyrosine kinases are novel modes of action in the treatment of relapsing multiple sclerosis, which are exhibited by minocycline and evobrutinib, respectively. Minocycline reduced conversion to multiple sclerosis in patients with a clinically isolated syndrome. Evobrutinib reduced MRI activity in a phase 2 trial, and a phase 3 trial is underway, in patients with relapsing multiple sclerosis. Diroximel fumarate is metabolised to monomethyl fumarate, the active metabolite of dimethyl fumarate, reduces circulating lymphocytes and modifies the activation profile of monocytes, and is being tested in this disease with the aim to improve gastrointestinal tolerability. The oral immunomodulator laquinimod did not reach the primary endpoint of reduction in confirmed disability progression in a phase 3 trial of patients with relapsing multiple sclerosis. In a phase 2 trial of patients with primary progressive multiple sclerosis, laquinimod also did not reach the primary endpoint of a reduction in brain volume loss, as a consequence the development of this drug will probably not be continued in multiple sclerosis. WHERE NEXT?: Several new oral compounds are in late-stage clinical development. With new modes of action introduced to the treatment of multiple sclerosis, the question of how to select and sequence different treatments in individual patients arises. Balancing risks with the expected efficacy of disease-modifying therapies will still be key for treatment selection. However, risks as well as efficacy can change when moving from the controlled clinical trial setting to clinical practice. Because some oral treatments, such as cladribine, have long-lasting effects on the immune system, the cumulative effects of sequential monotherapies can resemble the effects of a concurrent combination therapy. This treatment scheme might lead to higher efficacy but also to new safety concerns. These sequential treatments were largely excluded in phase 2 and 3 trials; therefore, monitoring both short-term and long-term effects of sequential disease-modifying therapies in phase 4 studies, cohort studies, and registries will be necessary.

Spatial and molecular changes of mouse brain metabolism in response to immunomodulatory treatment with teriflunomide as visualized by MALDI-MSI

Multiple sclerosis (MS) is an immune-mediated neurodegenerative disease of the central nervous system (CNS). One of the most promising recent medications for MS is teriflunomide. Its primary mechanism of action is linked to effects on the peripheral immune system by inhibiting dihydroorotate dehydrogenase (DHODH)-catalyzed de novo pyrimidine synthesis and reducing the expansion of lymphocytes in the peripheral immune system. Some in vitro studies suggested, however, that it can also have a direct effect on the CNS compartment. This potential alternative mode of action depends on the drug's capacity to traverse the blood-brain barrier (BBB) and to exert an effect on the complex network of brain biochemical pathways. In this paper, we demonstrate the application of high-resolution/high-accuracy matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry for molecular imaging of the mouse brain coronal sections from animals treated with teriflunomide. Specifically, in order to assess the effect of teriflunomide on the mouse CNS compartment, we investigated the feasibility of teriflunomide to traverse the BBB. Secondly, we systematically evaluated the spatial and semi-quantitative brain metabolic profiles of 24 different endogenous compounds after 4-day teriflunomide administration. Even though the drug was not detected in the examined cerebral sections (despite the high detection sensitivity of the developed method), in-depth study of the endogenous metabolic compartment revealed noticeable alterations as a result of teriflunomide administration compared to the control animals. The observed differences, particularly for purine and pyrimidine nucleotides as well as for glutathione and carbohydrate metabolism intermediates, shed some light on the potential impact of teriflunomide on the mouse brain metabolic networks. Graphical Abstract.

Perspectives of Patients with Multiple Sclerosis on Drug Treatment: A Qualitative Study

Background

Patients experience multiple sclerosis (MS) differently based on their disease type and other factors. This study aimed to explore the relative importance that patients with MS place on various attributes of MS drug therapies and to elucidate these patients' preferences regarding treatment characteristics such as administration, potential benefits, and side effects of the therapies.

Methods

Focus groups were conducted in Vancouver, Canada, with 23 adult patients with MS. Participants were interviewed in three groups based on disease category and MS treatment experience: treatment-naive, non-treatment-naive relapsing-remitting and non-treatment-naive progressive MS.

Results

Overall, the most important characteristics of MS drugs were effectiveness and side effects. As such, there is hesitancy about trying new-to-market drugs because the risks, benefits, and costs may not be well known. Participants valued stability in their treatment and generally did not want to take on the additional risk of trying a new drug if they felt that their current medication was providing benefit. Convenience and method of administration were secondary considerations that would generally be valued only if expected risks and benefits were considered equal or superior.

Conclusions

This qualitative study shows that patients consider the impact and likelihood of benefits and side effects first and foremost when making drug treatment decisions and that other factors, such as convenience and method of administration, are of secondary concern.

The role of optical coherence tomography and infrared oculography in assessing the visual pathway and CNS in multiple sclerosis

In this review, a current overview is provided of how optical coherence tomography and infrared oculography can aid in assessing the visual system and CNS in multiple sclerosis (MS). Both afferent and efferent visual disorders are common in MS and visual complaints can have a tremendous impact on daily functioning. Optical coherence tomography and infrared oculography can detect and quantify visual disorders with high accuracy, but could also serve as quantitative markers for inflammation, neurodegeneration and network changes including cognitive decline in MS patients. The assessment of the efferent and afferent visual pathways is relevant for monitoring and predicting the disease course, but is also potentially valuable as an outcome measure in therapeutic trials.

Beneficial effects of fingolimod in MS patients with high serum Sema4A levels

We previously demonstrated that patients with multiple sclerosis (MS) of high serum Sema4A levels are resistant to IFN-β therapy. To further elucidate the role of serum Sema4A as a biomarker for therapeutic stratification in MS patients, it is important to clarify the efficacy of other disease-modifying drugs (DMD) in those with high serum Sema4A levels. Thus, in this study we investigated whether fingolimod has beneficial effects on MS patients with high Sema4A levels. We retrospectively analyzed annualized relapse rate (ARR) and Expanded Disability Status Scale (EDSS) change in 56 relapsing—remitting multiple sclerosis (RRMS) patients who had been treated with fingolimod, including those who switched from IFN-β therapy. The levels of Sema4A in the sera were measured by sandwich ELISA. The implications of Sema4A on the efficacy of fingolimod were investigated by administering recombinant Sema4A-Fc and fingolimod to mice with experimental autoimmune encephalomyelitis (EAE). Retrospective analysis of MS cohort (17 high Sema4A and 39 low Sema4A) demonstrated the effectiveness of fingolimod in those with high serum Sema4A levels, showing reduction of ARR (from 1.21 to 0.12) and EDSS progression (from 0.50 to 0.04). Consistent with this observation, improvement in the disease severity of EAE mice receiving recombinant Sema4A-Fc was also observed after fingolimod treatment. These data suggest that fingolimod could serve as a candidate DMD for managing the disease activity of MS patients with high Sema4A levels.

Progressive multiple sclerosis: from pathogenic mechanisms to treatment

During the past decades, better understanding of relapsing-remitting multiple sclerosis disease mechanisms have led to the development of several disease-modifying therapies, reducing relapse rates and severity, through immune system modulation or suppression. In contrast, current therapeutic options for progressive multiple sclerosis remain comparatively disappointing and challenging. One possible explanation is a lack of understanding of pathogenic mechanisms driving progressive multiple sclerosis. Furthermore, diagnosis is usually retrospective, based on history of gradual neurological worsening with or without occasional relapses, minor remissions or plateaus. In addition, imaging methods as well as biomarkers are not well established. Magnetic resonance imaging studies in progressive multiple sclerosis show decreased blood-brain barrier permeability, probably reflecting compartmentalization of inflammation behind a relatively intact blood-brain barrier. Interestingly, a spectrum of inflammatory cell types infiltrates the leptomeninges during subpial cortical demyelination. Indeed, recent magnetic resonance imaging studies show leptomeningeal contrast enhancement in subjects with progressive multiple sclerosis, possibly representing an in vivo marker of inflammation associated to subpial demyelination. Treatments for progressive disease depend on underlying mechanisms causing central nervous system damage. Immunity sheltered behind an intact blood-brain barrier, energy failure, and membrane channel dysfunction may be key processes in progressive disease. Interfering with these mechanisms may provide neuroprotection and prevent disability progression, while potentially restoring activity and conduction along damaged axons by repairing myelin. Although most previous clinical trials in progressive multiple sclerosis have yielded disappointing results, important lessons have been learnt, improving the design of novel ones. This review discusses mechanisms involved in progressive multiple sclerosis, correlations between histopathology and magnetic resonance imaging studies, along with possible new therapeutic approaches.

Comparative effectiveness using a matching-adjusted indirect comparison between delayed-release dimethyl fumarate and fingolimod for the treatment of multiple sclerosis

OBJECTIVE

Delayed-release dimethyl fumarate (DMF; also known as gastro-resistant DMF) and fingolimod are approved oral disease-modifying treatments for relapsing-remitting multiple sclerosis. In phase 3 trials, DMF (DEFINE/CONFIRM) and fingolimod (FREEDOMS/FREEDOMS II) resulted in significant reductions in clinical and magnetic resonance imaging activity, with acceptable safety profiles. Direct comparisons of these treatments are not possible due to a lack of head-to-head trials. We compared 2 year efficacy of DMF versus fingolimod at the approved dosage using a matching-adjusted indirect approach.

RESEARCH DESIGN AND METHODS

Individual patient data from DEFINE and CONFIRM, and aggregate data from FREEDOMS and FREEDOMS II, were pooled and compared using the matching-adjusted in-direct method. To account for cross-trial differences, data from trials with available individual patient data were adjusted to match aggregate data (i.e. average patient characteristics) from trials without patient-level data. Data from DMF-treated patients were weighted such that average baseline characteristics matched those of fingolimod-treated patients. After matching, weighted treatment outcomes for DMF-treated patients (240 mg twice daily) were compared with summary outcomes for fingolimod-treated patients (0.5 mg once daily). All comparison results of DMF versus fingolimod used fingolimod as the reference.

RESULTS

After matching, baseline characteristics were balanced between DMF and fingolimod. At year 2, the efficacy of DMF was similar to that of fingolimod for annualized relapse rate (rate ratio [95% confidence interval (CI)]: 1.11 [0.88, 1.40]), 12 week confirmed disability progression (hazard ratio [95% CI]: 0.90 [0.63, 1.29]), and Multiple Sclerosis Functional Composite (mean difference [95% CI]: 0.04 [-0.05, 0.13]). For patient-reported outcomes (EuroQoL 5-Dimensions questionnaire), the mean differences (95% CI) were 0.05 (0.01, 0.08) for utility score and 3.22 (0.58, 5.86) for visual analog scale score, significantly favoring DMF. There was no significant difference in the percentage of patients with no evidence of disease activity (NEDA) for DMF versus fingolimod among matching-adjusted patients with complete NEDA data: rate ratio (95% CI): 0.92 (0.51, 1.64).

CONCLUSIONS

Using the matching-adjusted indirect comparison approach, the efficacy of DMF and fingolimod were similar on all clinical outcomes, while patient-reported outcomes showed greater benefit with DMF. Study limitations include possible confounding from unobserved/unknown differences between trials, and trial length may have been insufficient to detect significant differences on disability progression.

CLINICAL TRIAL REGISTRATION

NCT00420212 (DEFINE); NCT00451451 (CONFIRM); NCT00289978 (FREEDOMS); NCT00355134 (FREEDOMS II).

Fumarate modulates the immune/inflammatory response and rescues nerve cells and neurological function after stroke in rats

BACKGROUND

Dimethyl fumarate (DMF), working via its metabolite monomethylfumarate (MMF), acts as a potent antioxidant and immunomodulator in animal models of neurologic disease and in patients with multiple sclerosis. These properties and their translational potential led us to investigate whether DMF/MMF could also protect at-risk and/or dying neurons in models of ischemic stroke in vitro and in vivo. Although the antioxidant effects have been partially addressed, the benefits of DMF immunomodulation after ischemic stroke still need to be explored.

METHODS

In vitro neuronal culture with oxygen-glucose deprivation and rats with middle cerebral artery occlusion were subjected to DMF/MMF treatment. Live/dead cell counting and LDH assay, as well as behavioral deficits, plasma cytokine assay, western blots, real-time PCR (Q-PCR) and immunofluorescence staining, were used to evaluate the mechanisms and neurological outcomes.

RESULTS

We found that MMF significantly rescued cortical neurons from oxygen-glucose deprivation (OGD) in culture and suppressed pro-inflammatory cytokines produced by primary mixed neuron/glia cultures subjected to OGD. In rats, DMF treatment significantly decreased infarction volume by nearly 40 % and significantly improved neurobehavioral deficits after middle cerebral artery occlusion (MCAO). In the acute early phase (72 h after MCAO), DMF induced the expression of transcription factor Nrf2 and its downstream mediator HO-1, important for the protection of infarcted cells against oxidative stress. In addition to its antioxidant role, DMF also acted as a potent immunomodulator, reducing the infiltration of neutrophils and T cells and the number of activated microglia/macrophages in the infarct region by more than 50 % by 7-14 days after MCAO. Concomitantly, the levels of potentially harmful pro-inflammatory cytokines were greatly reduced in the plasma and brain and in OGD neuron/glia cultures.

CONCLUSIONS

We conclude that DMF is neuroprotective in experimental stroke because of its potent immunomodulatory and antioxidant effects and thus may be useful as a novel therapeutic agent to treat stroke in patients.

Recent trends in the transdermal delivery of therapeutic agents used for the management of neurodegenerative diseases

With the increasing proportion of the global geriatric population, it becomes obvious that neurodegenerative diseases will become more widespread. From an epidemiological standpoint, it is necessary to develop new therapeutic agents for the management of Alzheimer's disease, Parkinson's disease, multiple sclerosis and other neurodegenerative disorders. An important approach in this regard involves the use of the transdermal route. With transdermal drug delivery systems (TDDS), it is possible to modulate the pharmacokinetic profiles of these medications and improve patient compliance. Transdermal drug delivery has also been shown to be useful for drugs with short half-life and low or unpredictable bioavailability. In this review, several transdermal drug delivery enhancement technologies are being discussed in relation to the delivery of medications used for the management of neurodegenerative disorders.

Long-term treatment with low dose naltrexone maintains stable health in patients with multiple sclerosis

Introduction

A retrospective study was conducted on patients at Penn State Hershey Medical Center diagnosed with relapsing–remitting multiple sclerosis between 2006 and 2015.

Methodology

Laboratory and clinical data collected over this 10-year period were reviewed. Two cohorts of patients were established based on their relapsing–remitting multiple sclerosis therapy at the time of their first visit to Penn State. One group of patients (n = 23) was initially prescribed low dose naltrexone at the time first seen at Hershey. This group was offered low dose naltrexone because of symptoms of fatigue or refusal to take an available disease-modifying therapy. The second group of patients (n = 31) was treated with the glatiramer acetate (Copaxone) and offered low dose naltrexone as an adjunct therapy to their disease-modifying therapy.

Results

Patient data from visits after 1–50 months post-diagnosis were evaluated in a retrospective manner. Data obtained from patient charts included clinical laboratory values from standard blood tests, timed 25-foot walking trials, and changes in magnetic resonance imaging reports. Statistical analyses between the groups and for each patient over time indicated no significant differences in clinical laboratory values, timed walking, or changes in magnetic resonance imaging.

Conclusion

These data suggest that the apparently non-toxic, inexpensive, biotherapeutic is safe and if taken alone did not result in an exacerbation of disease symptoms.

Determinants of high cost in multiple sclerosis patients: a claims and chart review study

OBJECTIVE

To identify factors associated with high cost multiple sclerosis (MS) patients using integrated administrative claims and medical charts data.

METHODS

This study identified newly diagnosed MS patients (≥18 years) in a large United States managed care claims database between 1 January 2007 and 30 April 2011 using the ICD-9-CM code (340.xx). Mean annualized MS-related costs higher than the third quartile were categorized as high cost, lower than the first quartile as low, and the rest as medium. Patients were compared across cohorts with descriptive and inferential statistics. Baseline high cost factors were identified with multivariable logistic regression models.

RESULTS

Administrative claims (n = 4342) and medical chart records (n = 400) data was evaluated. Mean (SD) annualized MS-related costs were $6313 ($14,177) for patients overall and $18,398 ($24,483) for high cost patients. Inpatient costs accounted for the largest proportion (49.69%) of MS-related costs among high cost patients. MS relapses and MS-related comorbidities were more prevalent in the high cost patients. In the multivariable analyses, patients with baseline use of antidepressants or corticosteroids, baseline muscle weakness, and initial treatment from a non-neurologist were likelier to be high cost MS patients.

LIMITATIONS

MS-related clinical information was not completely available from medical chart data. The specificity of true MS-related costs may have been limited and the definition of the cost-based cohort segmentations was arbitrary.

CONCLUSIONS

Overall, baseline use of MS-related medications, the presence of baseline MS-related comorbidities, MS relapses, and MS-related hospitalizations were significantly associated with high cost patients. Future comparative effectiveness studies of currently approved disease modifying therapies for MS may help to identify best strategies for individual patients to minimize clinical events that are associated with high disease related costs.

Neurologic Diseases in Special Care Patients

Neurologic diseases can have a major impact on functional capacity. Patients with neurologic disease require individualized management considerations depending on the extent of impairment and impact on functional capacity. This article reviews 4 of the more common and significant neurologic diseases (Alzheimer disease, cerebrovascular accident/stroke, multiple sclerosis, and Parkinson disease) that are likely to present to a dental office and provides suggestions on the dental management of patients with these conditions.

Quantitative analysis of multiple sclerosis patients' preferences for drug treatment: a best-worst scaling study

BACKGROUND

With recent developments in drug therapy for multiple sclerosis (MS), new treatment options have become available presenting patients with complex treatment decisions.

OBJECTIVES

The objective of this study was to elicit patients' preferences for different attributes of MS drug therapy.

METHODS

A representative sample of patients with MS across Canada (n=189) participated in a best-worst scaling study to quantify preferences for different attributes of MS drug therapy, including delaying progression, improving symptoms, preventing relapse, minor side effects, rare but serious adverse events (SAEs), and route of administration. Conditional logit models were fitted to estimate the relative importance of each attribute in influencing patients' preferences.

RESULTS

A latent-class analysis revealed heterogeneity of preferences across respondents, with preferences differing across five classes. The most important attributes of drug therapy were the avoidance of SAEs for three classes and the improvement of symptoms for two other classes. Only a smaller group of patients demonstrated a specific preference for avoiding SAEs, and route of administration.

CONCLUSION

This study shows that preferences for drug therapy among patients with MS are different, some of which can be explained by experiences with their disease and treatment. These findings can help to inform the focus of interactions that healthcare practitioners have with patients with MS, as well as further drug development.

Disease-modifying therapies and infectious risks in multiple sclerosis

Immunomodulatory and immunosuppressive treatments for multiple sclerosis (MS) are associated with an increased risk of infection, which makes treatment of this condition challenging in daily clinical practice. Use of the expanding range of available drugs to treat MS requires extensive knowledge of treatment-associated infections, risk-minimizing strategies and approaches to monitoring and treatment of such adverse events. An interdisciplinary approach to evaluate the infectious events associated with available MS treatments has become increasingly relevant. In addition, individual stratification of treatment-related infectious risks is necessary when choosing therapies for patients with MS, as well as during and after therapy. Determination of the individual risk of infection following serial administration of different immunotherapies is also crucial. Here, we review the modes of action of the available MS drugs, and relate this information to the current knowledge of drug-specific infectious risks and risk-minimizing strategies.

Dimethyl fumarate in relapsing-remitting multiple sclerosis: rationale, mechanisms of action, pharmacokinetics, efficacy and safety

Dimethyl fumarate (DMF), a fumaric acid ester, is a new orally available disease-modifying agent that was recently approved by the US FDA and the EMA for the management of relapsing forms of multiple sclerosis (MS). Fumaric acid has been used for the management of psoriasis, for more than 50 years. Because of the known anti-inflammatory properties of fumaric acid ester, DMF was brought into clinical development in MS. More recently, neuroprotective and myelin-protective mechanism actions have been proposed, making it a possible candidate for MS treatment. Two Phase III clinical trials (DEFINE, CONFIRM) have evaluated the safety and efficacy of DMF in patients with relapsing-remitting MS. Being an orally available agent with a favorable safety profile, it has become one of the most commonly prescribed disease-modifying agents in the USA and Europe.

[Immunotherapy and infectious issues in multiple sclerosis. Self-injectable and oral drugs for immunotherapy]

Immunotherapy is generally associated with an increased risk for the development of infections. Due to the continuously expanding spectrum of new and potent immunotherapy treatment options for multiple sclerosis (MS), this article describes the currently known risks for treatment-related infections and the current recommendations for prevention of corresponding problems with drugs used in treatment strategies for MS and their mechanisms of action. The new treatment options in particular are linked to specific and severe infections; therefore, intensive and long-lasting monitoring is required before, during and after treatment and multidisciplinary surveillance of patients is needed. This article gives a detailed review of drug-specific red flags and current recommendations for the prophylaxis of infections associated with treatment of relapsing-remitting MS and when using self-injectable and oral disease-modifying immunotherapeutic drugs.

mir-181a-1/b-1 Modulates Tolerance through Opposing Activities in Selection and Peripheral T Cell Function

Understanding the consequences of tuning TCR signaling on selection, peripheral T cell function, and tolerance in the context of native TCR repertoires may provide insight into the physiological control of tolerance. In this study, we show that genetic ablation of a natural tuner of TCR signaling, mir-181a-1/b-1, in double-positive thymocytes dampened TCR and Erk signaling and increased the threshold of positive selection. Whereas mir-181a-1/b-1 deletion in mice resulted in an increase in the intrinsic reactivity of naive T cells to self-antigens, it did not cause spontaneous autoimmunity. Loss of mir-181a-1/b-1 dampened the induction of experimental autoimmune encephalomyelitis and reduced basal TCR signaling in peripheral T cells and their migration from lymph nodes to pathogenic sites. Taken together, these results demonstrate that tolerance can be modulated by microRNA gene products through the control of opposing activities in T cell selection and peripheral T cell function.

New opportunities of real-world data from clinical routine settings in life-cycle management of drugs: example of an integrative approach in multiple sclerosis

The assessment and demonstration of a positive benefit-risk balance of a drug is a life-long process and includes specific data from preclinical, clinical development and post-launch experience. However, new integrative approaches are needed to enrich evidence from clinical trials and sponsor-initiated observational studies with information from multiple additional sources, including registry information and other existing observational data and, more recently, health-related administrative claims and medical records databases. To illustrate the value of this approach, this paper exemplifies such a cross-package approach to the area of multiple sclerosis, exploring also possible analytic strategies when using these multiple sources of information.

Infection risk in patients on multiple sclerosis therapeutics

The interface of multiple sclerosis (MS) and infection occurs on several levels. First, infectious disease has been postulated as a potential trigger, if not cause, of MS. Second, exacerbation of MS has been well-documented as a consequence of infection, and, lastly, infectious diseases have been recognized as a complication of the therapies currently employed in the treatment of MS. MS is a disease in which immune dysregulation is a key component. Examination of central nervous system (CNS) tissue of people affected by MS demonstrates immune cell infiltration, activation and inflammation. Therapies that alter the immune response have demonstrated efficacy in reducing relapse rates and evidence of brain inflammation on magnetic resonance imaging (MRI). Despite the altered immune response in MS, there is a lack of evidence that these patients are at increased risk of infectious disease in the absence of treatment or debility. Links between infections and disease-modifying therapies (DMTs) used in MS will be discussed in this review, as well as estimates of occurrence and ways to potentially minimize these risks. We address infection in MS in a comprehensive fashion, including (1) the impact of infections on relapse rates in patients with MS; (2) a review of available infection data from pivotal trials and postmarketing studies for the approved and experimental DMTs, including frequency, types and severity of infections; and (3) relevant risk minimization strategies, particularly as they pertain to progressive multifocal leukoencephalopathy (PML).

Immunohistochemical detection of sphingosine-1-phosphate receptor 1 and 5 in human multiple sclerosis lesions

AIMS

Sphingosine-1-phosphate receptor (S1PR) modulating therapies are currently in the clinic or undergoing investigation for multiple sclerosis (MS) treatment. However, the expression of S1PRs is still unclear in the central nervous system under normal conditions and during neuroinflammation.

METHODS

Using immunohistochemistry we examined tissues from both grey and white matter MS lesions for sphingosine-1-phosphate receptor 1 (S1P1 ) and 5 (S1P5 ) expression. Tissues from Alzheimer's disease (AD) cases were also examined.

RESULTS

S1P1 expression was restricted to astrocytes and endothelial cells in control tissues and a decrease in endothelial cell expression was found in white matter MS lesions. In grey matter MS lesions, astrocyte expression was lost in active lesions, while in quiescent lesions it was restored to normal expression levels. CNPase colocalization studies demonstrated S1P5 expression on myelin and both were reduced in demyelinated lesions. In AD tissues we found no difference in S1P1 expression.

CONCLUSION

These data demonstrate a differential modulation of S1PRs in MS lesions, which may have an impact on S1PR-directed therapies.

Oral disease-modifying therapies for multiple sclerosis

Classical multiple sclerosis (MS) treatments using first-line injectable drugs, although widely applied, remain a major concern in terms of therapeutic adherence and efficacy. New oral drugs recently approved for MS treatment represent significant advances in therapy. The oral route of administration clearly promotes patient satisfaction and increases therapeutic compliance. However, these drugs may also have safety and tolerability issues, and a thorough analysis of the risks and benefits is required. Three oral drugs have been approved by regulatory agencies for MS treatment: fingolimod, teriflunomide, and dimethyl fumarate. This article reviews the mechanisms of action, safety, and efficacy of these drugs and two other drugs that have yielded positive results in phase III trials: cladribine and laquinimod.

Metabolic engineering of carbon and redox flow in the production of small organic acids

The review describes efforts toward metabolic engineering of production of organic acids. One aspect of the strategy involves the generation of an appropriate amount and type of reduced cofactor needed for the designed pathway. The ability to capture reducing power in the proper form, NADH or NADPH for the biosynthetic reactions leading to the organic acid, requires specific attention in designing the host and also depends on the feedstock used and cell energetic requirements for efficient metabolism during production. Recent work on the formation and commercial uses of a number of small mono- and diacids is discussed with redox differences, major biosynthetic precursors and engineering strategies outlined. Specific attention is given to those acids that are used in balancing cell redox or providing reduction equivalents for the cell, such as formate, which can be used in conjunction with metabolic engineering of other products to improve yields. Since a number of widely studied acids derived from oxaloacetate as an important precursor, several of these acids are covered with the general strategies and particular components summarized, including succinate, fumarate and malate. Since malate and fumarate are less reduced than succinate, the availability of reduction equivalents and level of aerobiosis are important parameters in optimizing production of these compounds in various hosts. Several other more oxidized acids are also discussed as in some cases, they may be desired products or their formation is minimized to afford higher yields of more reduced products. The placement and connections among acids in the typical central metabolic network are presented along with the use of a number of specific non-native enzymes to enhance routes to high production, where available alternative pathways and strategies are discussed. While many organic acids are derived from a few precursors within central metabolism, each organic acid has its own special requirements for high production and best compatibility with host physiology.

Patient preferences for disease-modifying drugs in multiple sclerosis therapy: a choice-based conjoint analysis

OBJECTIVES

With an increasing number of disease-modifying treatments (DMTs) for multiple sclerosis (MS), patient preferences will gain importance in the decision-making process. We assessed patients' implicit preferences for oral versus parenteral DMTs and identified factors influencing patients' treatment preference.

METHODS

Patients with relapsing-remitting MS (n = 156) completed a questionnaire assessing treatment preferences, whereby they had to decide between pairs of hypothetical treatment scenarios. Based on this questionnaire a choice-based conjoint analysis was conducted.

RESULTS

Treatment frequency and route of administration showed a stronger influence on patient preference compared with frequency of mild side effects. The latter attribute was more important for treatment-naïve patients compared with DMT-experienced patients. The higher the Extended Disability Status Scale score, the more likely pills, and the less likely fewer side effects were preferred. Pills were preferred over injections by 93% of patients, when treatment frequency and frequency of side effects were held constant. However, preference switched to injections when pills had to be taken three times daily and injections only once per week. Injections were also preferred when pills were associated with frequent side effects.

CONCLUSIONS

Our results suggest that route of administration and treatment frequency play an important role in the patients' preference for a given DMT.

A dam for retrograde axonal degeneration in multiple sclerosis?

OBJECTIVE

Trans-synaptic axonal degeneration is a mechanism by which neurodegeneration can spread from a sick to a healthy neuron in the central nervous system. This study investigated to what extent trans-synaptic axonal degeneration takes place within the visual pathway in multiple sclerosis (MS).

METHODS

A single-centre study, including patients with long-standing MS and healthy controls. Structural imaging of the brain (MRI) and retina (spectral-domain optical coherence tomography) were used to quantify the extent of atrophy of individual retinal layers and the primary and secondary visual cortex. Generalised estimation equations and multivariable regression analyses were used for comparisons.

RESULTS

Following rigorous quality control (OSCAR-IB), data from 549 eyes of 293 subjects (230 MS, 63 healthy controls) were included. Compared with control data, there was a significant amount of atrophy of the inner retinal layers in MS following optic neuritis (ON) and also in absence of ON. For both scenarios, atrophy stopped at the level of the inner nuclear layer. In contrast, there was significant localised atrophy of the primary visual cortex and secondary visual cortex in MS following ON, but not in MS in absence of ON.

INTERPRETATION

These data suggest that retrograde (trans-synaptic) axonal degeneration stops at the inner nuclear layer, a neuronal network capable of plasticity. In contrast, there seems to be no neuroplasticity of the primary visual cortex, rendering the structure vulnerable to anterograde (trans-synaptic) degeneration.

Molecular pharmacodynamics of new oral drugs used in the treatment of multiple sclerosis

New oral drugs have considerably enriched the therapeutic armamentarium for the treatment of multiple sclerosis. This review focuses on the molecular pharmacodynamics of fingolimod, dimethyl fumarate (BG-12), laquinimod, and teriflunomide. We specifically comment on the action of these drugs at three levels: 1) the regulation of the immune system; 2) the permeability of the blood-brain barrier; and 3) the central nervous system. Fingolimod phosphate (the active metabolite of fingolimod) has a unique mechanism of action and represents the first ligand of G-protein-coupled receptors (sphingosine-1-phosphate receptors) active in the treatment of multiple sclerosis. Dimethyl fumarate activates the nuclear factor (erythroid-derived 2)-related factor 2 pathway of cell defense as a result of an initial depletion of reduced glutathione. We discuss how this mechanism lies on the border between cell protection and toxicity. Laquinimod has multiple (but less defined) mechanisms of action, which make the drug slightly more effective on disability progression than on annualized relapse rate in clinical studies. Teriflunomide acts as a specific inhibitor of the de novo pyrimidine biosynthesis. We also discuss new unexpected mechanisms of these drugs, such as the induction of brain-derived neurotrophic factor by fingolimod and the possibility that laquinimod and teriflunomide regulate the kynurenine pathway of tryptophan metabolism.

Laquinimod therapy in multiple sclerosis: a comprehensive review

Introduction

Multiple sclerosis (MS) is considered an autoimmune disease with inflammatory and neurodegenerative underlying processes that affect the central nervous system. The available disease-modifying therapies (DMTs) approved to treat MS have only shown partial benefit in controlling the disease progression, primarily impeding its inflammatory component, while the parenteral administration of most of these therapies has shown to affect patient compliance. Laquinimod is a promising new oral drug recently evaluated in a third phase III clinical trial that demonstrated beneficial effects in delaying disease progression and preventing brain atrophy, suggesting a potential neuroprotective effect and a favorable safety profile.

Areas Covered

This is a comprehensive review covering clinical efficacy and safety data obtained from two phase III clinical trials, as well as the presumed beneficial mechanism of action, of laquinimod. This article also provides a short overview of the oral DMTs recently approved for the treatment of relapsing MS, as well as challenges that still remain to be overcome to fully control the relentless course of MS.

Conclusion

Laquinimod has been shown to have a novel immunomodulatory and potential neuroprotective mechanism of action as suggested from animal models and in vitro experimental data. Phase III clinical trials ALLEGRO (Clinicaltrials.gov #NCT00509145) and BRAVO (Clinicaltrials.gov #NCT00605215) have demonstrated clinical efficacy and tolerability, while the third phase III study is currently evaluating the safety and efficacy of laquinimod at a higher dosage. Emerging oral treatments like laquinimod will provide new options for patients to consider that can lead to better patient adherence and improved outcomes.

Electronic supplementary material

The online version of this article (doi:10.1007/s40120-014-0017-6) contains supplementary material, which is available to authorized users.

The effectiveness of dimethyl fumarate monotherapy in the treatment of relapsing-remitting multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Dimethyl fumarate (BG-12, Tecfidera®) is a new oral drug approved by FDA and EMA in March 2013 for relapsing - remitting multiple sclerosis (RRMS). The drug was much anticipated because of its possible superiority over currently available medications: fingolimod and teriflunomide as the only MS treatments currently available in oral form.

OBJECTIVE

The aim of this systematic review with meta-analysis was to assess the efficacy and safety of BG-12 in the treatment of RRMS.

METHODS

A systematic literature search was conducted in Medline/PubMed, EMBASE, and Cochrane Library up till 3(rd) November, 2013. We sought all published randomized clinical trials evaluating the use of dimethyl fumarate for the treatment of patients with RRMS. All included studies were critically appraised and analyzed with the use of Review Manager 5.1.0. software according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement protocol.

RESULTS

Two trials, DEFINE and CONFIRM involved 2 651 patients and compared dimethyl fumarate taken either two or three times daily with placebo in patients with RRMS. Additionally in CONFIRM trial third group of patients received glatiramer acetate. The overall results of the meta-analysis showed that BG-12 (at both dosages) given to patients with RRMS is safe and statistically significantly more effective than placebo in reducing the proportion of patients who had a relapse by 2 years, the rate of disability progression and the mean number of gadolinium-enhancing lesions at 2 years. The comparison between BG-12 and glatiramer acetate revealed that the analyzed agent could potentially be more effective in the treatment of RRMS.

CONCLUSIONS

Despite limited RCTs data available, both analyzed BG-12 regimens showed their efficacy on clinical disease parameters and other measures of disease activity in RRMS. The safety profile of the study agent was acceptable.

Multiple sclerosis treatment and infectious issues: update 2013

Immunomodulation and immunosuppression are generally linked to an increased risk of infection. In the growing field of new and potent drugs for multiple sclerosis (MS), we review the current data concerning infections and prevention of infectious diseases. This is of importance for recently licensed and future MS treatment options, but also for long-term established therapies for MS. Some of the disease-modifying therapies (DMT) go along with threats of specific severe infections or complications, which require a more intensive long-term monitoring and multi-disciplinary surveillance. We update the existing warning notices and infectious issues which have to be considered using drugs for multiple sclerosis.

Efficacy and safety of BG-12 (dimethyl fumarate) and other disease-modifying therapies for the treatment of relapsing-remitting multiple sclerosis: a systematic review and mixed treatment comparison

OBJECTIVE

Currently, direct comparative evidence or head-to-head data between BG-12 (dimethyl fumarate) and other disease-modifying treatments (DMTs) is limited. This study is a systematic review and data synthesis of published randomized clinical trials comparing the efficacy and safety of existing DMTs to BG-12 for relapsing-remitting multiple sclerosis (RRMS).

METHODS

A systematic review was conducted by searching MEDLINE, EMBASE, and the Cochrane Library for English-language publications from 1 January 1960 to 15 November 2012. Clinicaltrials.gov, metaRegister of Controlled Trials, and conference proceedings from relevant annual symposia were also hand searched. Two independent reviewers collected and extracted data, with discrepancies reconciled by a third reviewer. Included studies were randomized controlled trials (RCTs) of DMTs (interferon [IFN] beta-1a, IFN beta-1b, glatiramer acetate [GA], BG-12, fingolimod, natalizumab, and teriflunomide) in adults with RRMS. Mixed treatment comparisons were conducted to derive the relative effect size for the included treatments. Annualized relapse rate (ARR), disability progression, and safety outcomes were assessed.

RESULTS

BG-12 240 mg twice a day (BID) significantly reduces ARR compared to placebo (rate ratio: 0.529 [95% CI: 0.451-0.620]), IFNs (0.76 [95% CI: 0.639-0.904]), GA (0.795 [95% CI: 0.668-0.947]), and teriflunomide 7 mg and 14 mg (0.769 [95% CI: 0.610-0.970] and 0.775 [95% CI: 0.614-0.979]), and does not show a significant difference when compared to fingolimod. Only natalizumab was significantly superior to BG-12 in reducing ARR. BG-12 also demonstrated favorable results for disability and safety outcomes.

CONCLUSION

Based on indirect comparison, BG-12 offers an effective oral treatment option for patients with RRMS with an overall promising efficacy and safety profile compared to currently approved DMTs. Key limitations of the systematic review were the large heterogeneity in patients enrolled and the variability in the definition of outcomes in included trials.

Dimethyl fumarate

Each month, subscribers to The Formulary Monograph Service receive 5 to 6 well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to Pharmacy & Therapeutics Committees. Subscribers also receive monthly 1-page summary monographs on agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation/medication use evaluation (DUE/MUE) is also provided each month. With a subscription, the monographs are sent in print and are also available on-line. Monographs can be customized to meet the needs of a facility. A drug class review is now published monthly with The Formulary Monograph Service. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. For more information about The Formulary Monograph Service, call The Formulary at 800-322-4349. The September 2013 monograph topics are trametinib, simeprevir, paroxetine mesylate, and empagliflozin. The DUE/MUE is on aripiprazole.

Methylation differences at the HLA-DRB1 locus in CD4+ T-Cells are associated with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is thought to be caused by T-cell mediated autoimmune dysfunction. Risk of developing MS is influenced by environmental and genetic factors. Modifiable differences in DNA methylation are recognized as epigenetic contributors to MS risk and may provide a valuable link between environmental exposure and inherited genetic systems.

OBJECTIVES AND METHODS

To identify methylation changes associated with MS, we performed a genome-wide DNA methylation analysis of CD4+ T cells from 30 patients with relapsing-remitting MS and 28 healthy controls using Illumina 450K methylation arrays.

RESULTS

A striking differential methylation signal was observed at chr. 6p21, with a peak signal at HLA-DRB1. After prioritisation, we identified a panel of 74 CpGs associated with MS in this cohort. Most notably we found evidence of a major effect CpG island in DRB1 in MS cases (pFDR < 3 × 10(-3)). In addition, we found 55 non-HLA CpGs that exhibited differential methylation, many of which localise to genes previously linked to MS.

CONCLUSIONS

Our findings provide the first evidence for association of DNA methylation at HLA-DRB1 in relation to MS risk. Further studies are now warranted to validate and understand how these findings are involved in MS pathology.

Use of a standardized MxA protein measurement-based assay for validation of assays for the assessment of neutralizing antibodies against interferon-β

Effective monitoring of the development of neutralizing antibodies (NAbs) against IFN-β in multiple sclerosis (MS) patients on IFN-β therapy is important for clinical decision making and disease management. To date, antiviral assays have been the favored approach for NAb determination, but variations in assay conditions between laboratories and the increasing use of novel assays have contributed to the reporting of inconsistent antibody data between laboratories and between products. This study, undertaken at the request of the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA), is a joint effort by manufacturers of IFN-β products (approved in Europe) towards harmonization of a NAb assay that facilitates generation of comparable NAb data, which, in conjunction with clinical outcomes, should prove useful for clinicians treating MS patients with IFN-β products. This article describes the standardized cellular myxovirus resistance protein A (MxA) protein measurement-based assay for detection of IFN-β NAbs and its use for the validation of assays used for the quantitative determination of such antibodies. Although titers varied between laboratories and the products used, utilization of IFN-β1a rather than IFN-β1b as the challenge antigen produced more consistent results in the NAb assay. Adoption of the standardized assay improves comparability between laboratories circumventing problems that arise when different, nonstandardized assays are employed for immunogenicity assessment. Based on the data, the EMA recommended for standardization purposes, the use of IFN-β1a in NAb assays, independent of the therapeutic product used for therapy and validation of new NAb procedures against the standardized assay described.