Anti-JC virus antibodies in rituximab-treated patients with neuromyelitis optica spectrum disorder

B-cell proliferation characteristics and monitoring significance under the modified reduced-dose rituximab regimen for NMOSD: A real-world case series study

OBJECTIVE

To explore the B-cell proliferation characteristics and monitoring significance under the modified reduced-dose rituximab (mRTX) regimen for neuromyelitis optica spectrum disorder (NMOSD).

METHODS

NMOSD patients treated with mRTX were recruited, and the percentages of total CD19⁺ B cells and CD27⁺ memory B cells were dynamically detected by flow cytometry. The annualized relapse rate (ARR) and expanded disability status scale (EDSS) scores were compared before and after mRTX treatment, and the differences in B-cell values were compared between groups.

RESULTS

A total of 34 patients with NMOSD were ultimately enrolled. The EDSS score decreased from 2.5 (1.5, 3.0) to 1.3 (1.0, 2.0), and the ARR decreased from 1.0 (0, 2.0) to 0 (0, 0) (p < 0.001). Relapses occurred in 6 patients, with total CD19⁺ B-cell percentages of 3.25% (2.7%, 3.7%) and CD27⁺ memory B-cell percentages of 0.3% (0.2%, 0.3%) at initial relapse. Twenty-eight patients (82.4%) remained relapse-free with 84 doses of mRTX. Before 56 repeated doses, the total CD19⁺ B cells and CD27⁺ memory B cells were 4.00% (3.14%, 5.32%) and 0.26% (0.17%, 0.40%), respectively. The mean dosing interval was 9.2 months. Both total CD19⁺ B cells and CD27⁺ memory B cells proliferated over time after mRTX use, with significantly faster proliferation rates in the later stages. In 28 relapse-free patients, the mean time to reach 1% for total CD19⁺ B cells was 210 days, and the mean time to reach 3% was 240 days, with the mean interval from 1% to 3% of 65 days. Twenty-five relapse-free patients had no significant differences in maximum, minimum, and mean B-cell values compared to those of 6 patients with relapse.

CONCLUSION

The high rate of B-cell proliferation under the mRTX regimen indicates that closer dynamic B-cell monitoring is required to guide repeated mRTX dosing. Sustained depletion of total CD19⁺ B cells targeting < 3% of lymphocytes may be feasible, enabling extended dosing intervals.

High Seroprevalence and Index of Anti-John-Cunningham Virus Antibodies in Korean Patients with Multiple Sclerosis

Background and Purpose

The anti-John-Cunningham virus (JCV)-antibody serostatus and index are used in the risk stratification of progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS) patients treated with natalizumab. However, little information on these parameters is available for Asian countries. The purpose of this study was to determine the rate of seropositivity, index, and longitudinal index evolution in Korean patients with MS.

Methods

The antibody seroprevalence was analyzed in 355 samples from 187 patients with clinically isolated syndrome or MS using a second-generation, two-step, enzyme-linked immunosorbent assay. A 4-year longitudinal evaluation was applied to 66 patients.

Results

The overall antibody seroprevalence was 80% (n=149). Among antibody-positive patients, the index had a median value of 3.27 (interquartile range, 1.52–4.18), with 77% (n=114) and 56% (n=83) of patients having indices >1.5 and >3.0, respectively. The serostatus of 59 (89%) of the 66 patients did not change during the longitudinal analysis, while 3 (6%) of the 53 patients who were initially seropositive reverted to seronegativity, and 2 (15%) of the 13 patients who were initially seronegative converted to seropositivity. All patients with a baseline index >0.9 maintained seropositivity, and 92% of patients with a baseline index >1.5 maintained this index over 4 years. No patients developed PML (median disease duration, 8 years).

Conclusions

The seroprevalence and index of anti-JCV antibodies in Korean patients with MS may be higher than those in Western countries.

Individualized B cell-targeting therapy for neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune inflammatory disease of the central nervous system characterized by severe attacks of optic neuritis (ON), longitudinally extensive transverse myelitis (LETM), and area postrema syndrome. The majority of patients with NMOSD are seropositive for autoantibodies against the astrocyte water channel aquaporin-4 (AQP4). As convergent clinical and laboratory-based investigations have indicated that B cells play a fundamental role in NMO immunopathology, B cells have become an attractive therapeutic target. Rituximab is a therapeutic monoclonal antibody against CD20 expressed on B cells and increasingly used for the treatment of NMOSD. Although there is robust evidence for the efficacy and safety of rituximab in NMOSD, considerable variability has been noted in biological and clinical responses in patients. Therefore, the focus now is on understanding the mechanisms underlying the variability in response to rituximab and optimizing the use of rituximab for NMOSD. Identification of biomarkers for prediction of clinical response, and effective dosing and timing of treatment may provide useful tools for patient-tailored treatment in NMOSD. Herein, we review current evidence on factors that affect biological and clinical responses to rituximab and highlight the importance of individualized therapies for NMOSD.

Systematic review of the published data on the worldwide prevalence of John Cunningham virus in patients with multiple sclerosis and neuromyelitis optica

OBJECTIVES

John Cunningham virus (JCV) is a polyoma virus that infects humans, mainly in childhood or adolescence, and presents no symptomatic manifestations. JCV can cause progressive multifocal leukoencephalopathy (PML) in immunosuppressed individuals, including those undergoing treatment for multiple sclerosis (MS) and neuromyelitis optica (NMO). PML is a severe and potentially fatal disease of the brain. The prevalence of JCV antibodies in human serum has been reported to be between 50.0 and 90.0%. The aim of the present study was to review worldwide data on populations of patients with MS and NMO in order to establish the rates of JCV seropositivity in these individuals.

METHODS

The present review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and used the following search terms: “JCV” OR “JC virus” AND “multiple sclerosis” OR “MS” OR “NMO” OR “neuromyelitis optica” AND “prevalence.” These terms were searched for both in smaller and in larger clusters of words. The databases searched included PubMed, MEDLINE, SciELO, LILACS, Google Scholar, and Embase.

RESULTS

After the initial selection, 18 papers were included in the review. These articles reported the prevalence of JCV antibodies in the serum of patients with MS or NMO living in 26 countries. The systematic review identified data on 29,319 patients with MS/NMO and found that 57.1% of them (16,730 individuals) were seropositive for the anti-JCV antibody (range, 40.0 to 69.0%).

CONCLUSIONS

The median worldwide prevalence of JCV among adults with MS or NMO was found to be 57.1%.

Acquired haemophilia A complicating alemtuzumab therapy for multiple sclerosis

Alemtuzumab is a highly efficacious therapy used in the treatment of multiple sclerosis (MS), but uncoupling of T and B cell repopulation during immune reconstitution associates with an increasing range of secondary B cell-mediated autoimmune complications. A 34-year-old woman developed Graves' disease 11 months following an initial course of alemtuzumab treatment for MS. Nine months following the second treatment with alemtuzumab, the patient presented with spontaneous intramuscular and subcutaneous haemorrhage due to development of an inhibitory autoantibody to coagulation factor VIII. Acquired haemophilia A (AHA) is an extremely rare complication in patients treated with alemtuzumab. Treatment with rituximab may induce a rapid remission of AHA; however, the patient's high John Cunningham virus (JCV) antibody index and alemtuzumab-induced T cell lymphopenia may lead to an increased risk of progressive multifocal leucoencephalopathy, a potential complication which was unacceptable to the patient.

Infections in Patients Receiving Multiple Sclerosis Disease-Modifying Therapies

PURPOSE OF REVIEW

This paper will systemically review the risk of infections associated with current disease-modifying treatments and will discuss pre-treatment testing recommendations, infection monitoring strategies, and patient education.

RECENT FINDINGS

Aside from glatiramer acetate and interferon-beta therapies, all other multiple sclerosis treatments to various degrees impair immune surveillance and may predispose patients to the development of both community-acquired and opportunistic infections. Some of these infections are rarely seen in neurologic practice, and neurologists should be aware of how to monitor for these infections and how to educate patients about medication-specific risks. Of particular interest in this discussion is the risk of PML in association with the recently approved B cell depleting therapy, ocrelizumab, particularly when switching from natalizumab. The risk of infection in association with MS treatments has become one of the most important factors in the choice of therapy. Balance of the overall risk versus benefit should be continuously re-evaluated during treatment.

What's new in neuromyelitis optica? A short review for the clinical neurologist

The evolution of neuromyelitis optica spectrum disorder (NMOSD) from a rare, incurable and misunderstood disease with almost universally poor outcomes to its present state in just over a decade is unprecedented in neurology and possibly in medicine. Our knowledge of NMOSD biology has led to the recognition of wider phenotypes, new disease mechanisms, and thus clinical trials of new and effective treatments. This article aims to update readers on the recent developments in NMOSD with particular emphasis on clinical advances, the 2015 diagnostic criteria, biomarkers, imaging, and therapeutic interventions.

Monoclonal antibody therapy for neuromyelitis optica spectrum disorder: current and future

Monoclonal-antibody has been used for patients with autoimmune disorders for several years, and efficacy and safety were appreciated for these patients. Neuromyelitis optica specturm disorder (NMOSD) has been defined as an autoimmune demyelination disorder of the central nervous system (CNS) with a course of relapse-remission. Treatment of prevention is important for patients with NMOSD because of the increased disability after several attacks. Multiple factors were involved in the pathogenesis of NMOSD. Currently, targeting specific factor was favored in the research into the treatment for NMOSD. Previous studies reported the efficacy and tolerance in NMOSD for drugs such as rituximab, tocilizumab, and eculizumab. The aim of this article is to review the current monoclonal therapies for NMOSD patients, and also future alternative options.

Neuromyelitis optica: Contribution of therapeutic responses markers monitoring in patients given rituximab

Neuromyelitis optica (NMO) is a central nervous system inflammatory autoimmune disease characterized by medullary and/or optical nerve damage. It is rare but life-threatening. Concerning the treatment of NMO, many drugs have been used in background therapy. Some studies have shown efficacy of rituximab (an antiCD20 monoclonal anti-body) either on the reduction of the annual number of exacerbation or the mean score EDSS. In 2013, a Korean team reported a new protocol during which they administered rituximab only when memory B lymphocytes CD27+ were detectable in the bloodstream. In our patient, institution of this protocol led to clinical benefit with a major decrease in the EDSS score over time (7 in August 2012 vs. 1 in October 2015), a reduction of the total administered dose (4g in 2013 vs. 1.375g in 2014 vs. 0g in 2015) and side effects. Compared with the rate of theoretical administration, health expenditure savings reached 1700 Euros per month over the 11-month treatment. Monitoring therapeutic response markers with memory B lymphocyte counts appear to be an efficient cost-effective way to measure clinical efficiency, reduce total doses, and limit side effects.