Safety of monoclonal antibodies for the treatment of multiple sclerosis

B Cells and Autoantibodies in AIRE Deficiency

Autoimmune polyendocrine syndrome type 1 (APS-1) is a rare but severe monogenetic autoimmune endocrine disease caused by failure of the Autoimmune Regulator (AIRE). AIRE regulates the negative selection of T cells in the thymus, and the main pathogenic mechanisms are believed to be T cell-mediated, but little is known about the role of B cells. Here, we give an overview of the role of B cells in thymic and peripheral tolerance in APS-1 patients and different AIRE-deficient mouse models. We also look closely into which autoantibodies have been described for this disorder, and their implications. Based on what is known about B cell therapy in other autoimmune disorders, we outline the potential of B cell therapies in APS-1 and highlight the unresolved research questions to be answered.

Anti-severe acute respiratory syndrome coronavirus-2 antibody responses following Pfizer-BioNTech vaccination in a patient with multiple sclerosis treated with ocrelizumab: a case report

Patients with multiple sclerosis (MS) repeatedly receive therapies that cause B-lymphocyte depletion. This may lead to abnormal immune responses following coronavirus disease 2019 (COVID-19) vaccination, as has been suggested previously. We therefore evaluated post-vaccination immune responses in a patient with MS treated with ocrelizumab. The intervals between ocrelizumab infusions and vaccination were as recommended by the Section of Multiple Sclerosis and Neuroimmunology of the Polish Neurological Society. A reactive immune response was observed in this patient following vaccination. This suggests that appropriate intervals between ocrelizumab infusions and COVID-19 vaccinations may permit the generation of efficacious immune responses in patients receiving B-lymphocyte depleting therapies.

Risk Assessment of Progressive Multifocal Leukoencephalopathy in Multiple Sclerosis Patients during 1 Year of Ocrelizumab Treatment

Background: Progressive multifocal leukoencephalopathy (PML) caused by the JC virus is the main limitation to the use of disease modifying therapies for treatment of multiple sclerosis (MS). Methods: To assess the PML risk in course of ocrelizumab, urine and blood samples were collected from 42 MS patients at baseline (T0), at 6 (T2) and 12 months (T4) from the beginning of therapy. After JCPyV-DNA extraction, a quantitative-PCR (Q-PCR) was performed. Moreover, assessment of JCV-serostatus was obtained and arrangements’ analysis of non-coding control region (NCCR) and of viral capsid protein 1 (VP1) was carried out. Results: Q-PCR revealed JCPyV-DNA in urine at all selected time points, while JCPyV-DNA was detected in plasma at T4. From T0 to T4, JC viral load in urine was detected, increased in two logarithms and, significantly higher, compared to viremia. NCCR from urine was archetypal. Plasmatic NCCR displayed deletion, duplication, and point mutations. VP1 showed the S269F substitution involving the receptor-binding region. Anti-JCV index and IgM titer were found to statistically decrease during ocrelizumab treatment. Conclusions: Ocrelizumab in JCPyV-DNA positive patients is safe and did not determine PML cases. Combined monitoring of ocrelizumab’s effects on JCPyV pathogenicity and on host immunity might offer a complete insight towards predicting PML risk.

Regulation of B cell functions by S-nitrosoglutathione in the EAE model

B cells play both protective and pathogenic roles in T cell-mediated autoimmune diseases by releasing regulatory vs. pathogenic cytokines. B cell-depleting therapy has been attempted in various autoimmune diseases but its efficacy varies and can even worsen symptoms due to depletion of B cells releasing regulatory cytokines along with B cells releasing pathogenic cytokines. Here, we report that S-nitrosoglutathione (GSNO) and GSNO-reductase (GSNOR) inhibitor N6022 drive upregulation of regulatory cytokine (IL-10) and downregulation of pathogenic effector cytokine (IL-6) in B cells and protected against the neuroinflammatory disease of experimental autoimmune encephalomyelitis (EAE). In human and mouse B cells, the GSNO/N6022-mediated regulation of IL-10 vs. IL-6 was not limited to regulatory B cells but also to a broad range of B cell subsets and antibody-secreting cells. Adoptive transfer of B cells from N6022 treated EAE mice or EAE mice deficient in the GSNOR gene also regulated T cell balance (Treg > Th17) and reduced clinical disease in the recipient EAE mice. The data presented here provide evidence of the role of GSNO in shifting B cell immune balance (IL-10 > IL-6) and the preclinical relevance of N6022, a first-in-class drug targeting GSNOR with proven human safety, as therapeutics for autoimmune disorders including multiple sclerosis.

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GSNO and GSNOR inhibitor (N6022) upregulates IL-10 and downregulates IL-6 in B cells.

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GSNO/N6022-mediated cytokine regulation occurs in a broad range of B cell subsets.

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GSNO/N6022 treatment ameliorates autoimmune disease of EAE.

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B cell transfer from N6022-treated or GSNOR null EAE mice to EAE mice shifts T cell balance (Treg > Th17) and alleviates EAE.

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The data provide the first insight into the therapeutic potential of GSNO/N6022 targeting B cells in multiple sclerosis.

B Cells and Antibodies as Targets of Therapeutic Intervention in Neuromyelitis Optica Spectrum Disorders

The first description of neuromyelitis optica by Eugène Devic and Fernand Gault dates back to the 19th century, but only the discovery of aquaporin-4 autoantibodies in a major subset of affected patients in 2004 led to a fundamentally revised disease concept: Neuromyelits optica spectrum disorders (NMOSD) are now considered autoantibody-mediated autoimmune diseases, bringing the pivotal pathogenetic role of B cells and plasma cells into focus. Not long ago, there was no approved medication for this deleterious disease and off-label therapies were the only treatment options for affected patients. Within the last years, there has been a tremendous development of novel therapies with diverse treatment strategies: immunosuppression, B cell depletion, complement factor antagonism and interleukin-6 receptor blockage were shown to be effective and promising therapeutic interventions. This has led to the long-expected official approval of eculizumab in 2019 and inebilizumab in 2020. In this article, we review current pathogenetic concepts in NMOSD with a focus on the role of B cells and autoantibodies as major contributors to the propagation of these diseases. Lastly, by highlighting promising experimental and future treatment options, we aim to round up the current state of knowledge on the therapeutic arsenal in NMOSD.

Newly approved agents for relapsing remitting multiple sclerosis: how real-world evidence compares with randomized clinical trials?

INTRODUCTION

In recent years, many treatment options have become available for relapsing remitting MS. Randomized clinical trials and real-world studies are complementary sources of information, and together have the potential to offer a comprehensive understanding of the safety and efficacy profiles of each drug, a critical factor for a personalized management of the disease.

AREAS COVERED

In this review, the authors provide an up-to-date review of both RCTs and real-world studies assessing the safety and efficacy profiles of recently developed disease-modifying drugs for relapsing remitting MS. These include fingolimod, teriflunomide, dimethyl fumarate, alemtuzumab and ocrelizumab.

EXPERT OPINION

From the authors' review of the literature, the efficacy profiles resulted from RCTs were confirmed by observational studies with regard to the disease-modifying drugs considered. The magnitude of the effects on annualized relapse rates and MRI active lesions was generally even larger in the observational studies compared to RCTs. From the safety point of view, observational studies revealed new adverse events, mostly in the area of bacterial and opportunistic infections, not seen in the relative registration programme. This is a very important gain because it allows to elaborate appropriate strategies to prevent and handle the risks.

Contributions of Major Cell Populations to Sjögren's Syndrome

Sjögren’s syndrome (SS) is a female dominated autoimmune disease characterized by lymphocytic infiltration into salivary and lacrimal glands and subsequent exocrine glandular dysfunction. SS also may exhibit a broad array of extraglandular manifestations including an elevated incidence of non-Hodgkin’s B cell lymphoma. The etiology of SS remains poorly understood, yet progress has been made in identifying progressive stages of disease using preclinical mouse models. The roles played by immune cell subtypes within these stages of disease are becoming increasingly well understood, though significant gaps in knowledge still remain. There is evidence for distinct involvement from both innate and adaptive immune cells, where cells of the innate immune system establish a proinflammatory environment characterized by a type I interferon (IFN) signature that facilitates propagation of the disease by further activating T and B cell subsets to generate autoantibodies and participate in glandular destruction. This review will discuss the evidence for participation in disease pathogenesis by various classes of immune cells and glandular epithelial cells based upon data from both preclinical mouse models and human patients. Further examination of the contributions of glandular and immune cell subtypes to SS will be necessary to identify additional therapeutic targets that may lead to better management of the disease.

Differential Effects of MS Therapeutics on B Cells-Implications for Their Use and Failure in AQP4-Positive NMOSD Patients

B cells are considered major contributors to multiple sclerosis (MS) pathophysiology. While lately approved disease-modifying drugs like ocrelizumab deplete B cells directly, most MS medications were not primarily designed to target B cells. Here, we review the current understanding how approved MS medications affect peripheral B lymphocytes in humans. These highly contrasting effects are of substantial importance when considering these drugs as therapy for neuromyelitis optica spectrum disorders (NMOSD), a frequent differential diagnosis to MS, which is considered being a primarily B cell- and antibody-driven diseases. Data indicates that MS medications, which deplete B cells or induce an anti-inflammatory phenotype of the remaining ones, were effective and safe in aquaporin-4 antibody positive NMOSD. In contrast, drugs such as natalizumab and interferon-β, which lead to activation and accumulation of B cells in the peripheral blood, lack efficacy or even induce catastrophic disease activity in NMOSD. Hence, we conclude that the differential effect of MS drugs on B cells is one potential parameter determining the therapeutic efficacy or failure in antibody-dependent diseases like seropositive NMOSD.

Direct T-cell Inhibition and Agents Targeting T-cell Migration and Chemotaxis

Lymphocyte depletion and blockade of T-cell activation and trafficking serve as therapeutic strategies for an enlarging number of immune-mediated diseases and malignancies. This review summarizes the infection risks associated to monoclonal antibodies that bind to the α chain of the interleukin-2 receptor, the cell surface glycoprotein CD52, and members of α4- and β2-integrin families acting as cell-adhesion molecules. An outline of the mechanisms of action, approved indications and off-label uses, expected impact on the host immune response, and available clinical evidence is provided for each of these agents.

Developing a Model of Care for Home Infusions of Natalizumab for People With Multiple Sclerosis

Natalizumab is an effective treatment for multiple sclerosis that requires 4-weekly infusions that are usually provided in hospital outpatient clinics. In this study, a model of care (MOC), an overarching design for the provision of a health care service, was developed to permit home infusions of natalizumab. The proposed new MOC comprised 9 dimensions, in addition to the central concept of patient-centered care at home. The new MOC is responsive to patient needs and prioritizes the nurse-patient therapeutic relationship. It provides practical examples of patient-centered care to guide clinical practice for this patient population in the home setting.

Safety outcomes of disease-modifying therapies for relapsing-remitting multiple sclerosis: A network meta-analysis

BACKGROUND

Randomised clinical trials (RCTs) and observational studies have reported adverse events that preclude the use of disease-modifying therapies (DMTs) in relapsing-remitting multiple sclerosis (RRMS) in the long term or in specific populations, however, little is known about the relationship between the use of DMTs and frequency of undesirable events. We aimed to conduct a systematic review and network meta-analyses (NMAs) of RCTs and observational studies to synthesise the evidence on the safety of all available DMTs for patients with RRMS.

METHODS

PubMed, Scopus and a manual search were performed. Bayesian NMAs of safety outcomes reported in RCTs and observational studies assessing DMTs as monotherapies were conducted.

RESULTS

Forty-seven studies were included in the systematic review. Considering all studies, 368 and 149 different safety outcomes were reported for at least one study and two studies, respectively. Considering clinical trials, 22 NMAs were conducted for 16 outcomes. Regarding geometry metrics, the median number of studies, DMTs, common comparator, strong edge, and patients were 5 (IQR 5-9), 5 (IQR 4-8), 44%, 33%, and 3998 (IQR 3380-6761). In summary, most comparisons showed similar risk of safety events for DMTs and placebo for all outcomes. Considering cohort studies, only three meta-analyses were conducted.

CONCLUSION

Safety outcomes are poorly reported in primary studies of DMTs in RRMS, precluding the conduction of robust meta-analyses. Therefore, the current available data on safety of these drugs is not contributing to regulatory and clinical decision making, with adverse event reports underbalanced compared to efficacy outcomes.

Efficacy and Safety of Rituximab for the Treatment of Graves' Orbitopathy: A Meta-analysis of Randomized Controlled Trials

STUDY OBJECTIVE

To investigate the efficacy and safety of rituximab in patients with Graves' orbitopathy (GO).

DESIGN

Systematic review and meta-analysis of four randomized controlled trials.

PATIENTS

A total of 293 patients with GO who received rituximab or control (either glucocorticoids, the established first-line therapy [three trials], or saline [one trial]).

MEASUREMENTS AND RESULTS

Relevant studies published before February 2018 were identified from the PubMed, EMBASE, Cochrane Library, and Scopus databases and the ClinicalTrials.gov registry. Individual effect sizes were standardized, and a meta-analysis was conducted to calculate the pooled effect size by using a random-effects model. Treatment efficacy was assessed by measuring the following outcomes: clinical activity score (CAS), sight visual acuity reduction (NOSPECS) score, proptosis, diplopia, changes in eye volume, quality of life, and adverse events. In the four included trials, 113 patients in the rituximab group and 108 patients in the control group were evaluated. Compared with the control group, CAS (weighted mean difference 0.57, 95% confidence interval 0.25-0.89) was significantly reduced at 24 weeks in the rituximab group. Compared with the control group, considerable proptosis reduction was also observed in the rituximab group; however, the difference was not significant. The proportion of adverse events in the rituximab group was not significantly higher than that in the glucocorticoid control group, but one of the included trials indicated that the rituximab group had more serious adverse events than the saline control group.

CONCLUSION

Rituximab is a relatively safe and viable treatment that is superior to glucocorticoids or saline for patients with moderate to severe GO. However, the incidence of serious adverse events was disparate among the included trials. Additional studies involving a larger sample size and investigating the optimal rituximab dosage, frequency, and method of administration are warranted.

Disease-Modifying Therapies for Relapsing-Remitting Multiple Sclerosis: A Network Meta-Analysis

BACKGROUND

A broad range of disease-modifying therapies (DMTs) for relapsing-remitting multiple sclerosis (RRMS) is available. However, the efficacy and safety of traditional DMTs compared with the recently developed DMTs remain unclear.

OBJECTIVE

Therefore, we have synthesised available evidence of clinical outcomes for DMTs in adults with RRMS.

METHODS

PubMed, Scopus and a manual search were performed. Bayesian network meta-analyses of randomised clinical trials assessing DMTs as monotherapies were conducted. SUCRA and GRADE were used to rank therapies and to assess quality of general evidence, respectively.

RESULTS

Thirty-three studies were included in the meta-analyses. The most effective therapies for the outcome of annualised relapse rate were alemtuzumab (96% probability), natalizumab (96%) and ocrelizumab (85%), compared with all other therapies (hazard ratio versus placebo, 0.31, 0.31 and 0.37, respectively; p < 0.05 for all comparisons) (high-quality evidence). However, no significant differences among these three therapies were found. Discontinuation due to adverse events revealed similarity across all therapies, except for alemtuzumab, which showed less discontinuation when compared with interferon-1a intramuscular (relative risk 0.37; p < 0.05).

CONCLUSION

High-quality evidence shows that alemtuzumab, natalizumab and ocrelizumab present the highest efficacy among DMTs, and other meta-analyses are required regarding adverse events frequency, to better understand the safety of therapies. Based on efficacy profile, guidelines should consider a three-category classification (i.e. high, intermediate and low efficacy).

Pharmacotherapy in Secondary Progressive Multiple Sclerosis: An Overview

Multiple sclerosis is an immune-mediated inflammatory disease of the central nervous system characterised by demyelination, neuroaxonal loss and a heterogeneous clinical course. Multiple sclerosis presents with different phenotypes, most commonly a relapsing-remitting course and, less frequently, a progressive accumulation of disability from disease onset (primary progressive multiple sclerosis). The majority of people with relapsing-remitting multiple sclerosis, after a variable time, switch to a stage characterised by gradual neurological worsening known as secondary progressive multiple sclerosis. We have a limited understanding of the mechanisms underlying multiple sclerosis, and it is believed that multiple genetic, environmental and endogenous factors are elements driving inflammation and ultimately neurodegeneration. Axonal loss and grey matter damage have been regarded as amongst the leading causes of irreversible neurological disability in the progressive stages. There are over a dozen disease-modifying therapies currently licenced for relapsing-remitting multiple sclerosis, but none of these has provided evidence of effectiveness in secondary progressive multiple sclerosis. Recently, there has been some early modest success with siponimod in secondary progressive multiple sclerosis and ocrelizumab in primary progressive multiple sclerosis. Finding treatments to delay or prevent the courses of secondary progressive multiple sclerosis is an unmet and essential goal of the research in multiple sclerosis. In this review, we discuss new findings regarding drugs with immunomodulatory, neuroprotective or regenerative properties and possible treatment strategies for secondary progressive multiple sclerosis. We examine the field broadly to include trials where participants have progressive or relapsing phenotypes. We summarise the most relevant results from newer investigations from phase II and III randomised controlled trials over the past decade, with particular attention to the last 5 years.

Human Tregs Made Antigen Specific by Gene Modification: The Power to Treat Autoimmunity and Antidrug Antibodies with Precision

Human regulatory CD4⁺ T cells (Tregs) are potent immunosuppressive lymphocytes responsible for immune tolerance and homeostasis. Since the seminal reports identifying Tregs, vast research has been channeled into understanding their genesis, signature molecular markers, mechanisms of suppression, and role in disease. This research has opened the doors for Tregs as a potential therapeutic for diseases and disorders such as multiple sclerosis, type I diabetes, transplantation, and immune responses to protein therapeutics, like factor VIII. Seminal clinical trials have used polyclonal Tregs, but the frequency of antigen-specific Tregs among polyclonal populations is low, and polyclonal Tregs may risk non-specific immunosuppression. Antigen-specific Treg therapy, which uses genetically modified Tregs expressing receptors specific for target antigens, greatly mitigates this risk. Building on the principles of T-cell receptor cloning, chimeric antigen receptors (CARs), and a novel CAR derivative, called B-cell antibody receptors, our lab has developed different types of antigen-specific Tregs. This review discusses the current research and optimization of gene-modified antigen-specific human Tregs in our lab in several disease models. The preparations and considerations for clinical use of such Tregs also are discussed.

Nogo-A Antibodies for Progressive Multiple Sclerosis

Most of the current therapies, as well as many of the clinical trials, for multiple sclerosis (MS) target the inflammatory autoimmune processes, but less than 20% of all clinical trials investigate potential therapies for the chronic progressive disease stage of MS. The latter is responsible for the steadily increasing disability in many patients, and there is an urgent need for novel therapies that protect nervous system tissue and enhance axonal growth and/or remyelination. As outlined in this review, solid pre-clinical data suggest neutralization of the neurite outgrowth inhibitor Nogo-A as a potential new way to achieve both axonal and myelin repair. Several phase I clinical studies with anti-Nogo-A antibodies have been conducted in different disease paradigms including MS and spinal cord injury. Data from spinal cord injury and amyotrophic lateral sclerosis (ALS) trials accredit a good safety profile of high doses of anti-Nogo-A antibodies administered intravenously or intrathecally. An antibody against a Nogo receptor subunit, leucine rich repeat and immunoglobulin-like domain-containing protein 1 (LINGO-1), was recently shown to improve outcome in patients with acute optic neuritis in a phase II study. Nogo-A-suppressing antibodies could be novel drug candidates for the relapsing as well as the progressive MS disease stage. In this review, we summarize the available pre-clinical and clinical evidence on Nogo-A and elucidate the potential of Nogo-A-antibodies as a therapy for progressive MS.