Drug-induced progressive multifocal leukoencephalopathy in multiple sclerosis: A comprehensive review

Association of temozolomide with progressive multifocal leukoencephalopathy: a disproportionality analysis integrated with network pharmacology

BACKGROUND

Temozolomide (TMZ) is an alkylating agent approved for the management of glioblastoma. The TMZ is not known for progressive multifocal leukoencephalopathy (PML). The main objective of the current study is to find out the association of TMZ with PML using disproportionality analysis of FDA Adverse Event Reporting System (FAERS) data integrated with network pharmacological approaches.

RESEARCH DESIGN AND METHODS

OpenVigil tool was used to query the FAERS database. The disproportionality measures were calculated. The network has been constructed using Cytoscape. Finally, the possible binding interactions were studied using Glide, Schrödinger Inc.

RESULTS

A total number of 3502 cases of PML were reported in the FAERS database. Out of these, 10 cases were found with TMZ. The subgroup analysis results have shown a greater number of cases in females. The network has indicated the involvement of human mitogen-activated protein kinase, 3-phosphoinositide-dependent protein kinase 1 protein, human mTOR complex protein, phosphatidylinositol 4,5-bisphosphate 3-kinase protein, and glycogen synthase kinase-3 beta protein. The docking results have indicated good interactions of TMZ with active site of glycogen synthase kinase-3 beta and mitogen-activated protein kinase 1 as compared to other identified targets.

CONCLUSION

The PML is identified as novel signal with temozolomide.

The evolution of multiple sclerosis disease-modifying therapies: An update for pharmacists

PURPOSE

Multiple sclerosis (MS) and the evolution of disease-modifying therapies (DMTs) and their indications, mechanisms of action, efficacy, pregnancy class, and cost are discussed.

SUMMARY

MS is an immune-mediated, demyelinating, and progressive neurological disorder that can cause both motor and cognitive deficits. Onset of MS typically occurs between the ages of 20 and 40 years, and the disease can result in significant disability over time. Since the introduction of the first DMT for the treatment of MS in 1993, significant progress has been made in the development of new classes of DMTs with different mechanisms of action, higher efficacy, and simpler administration schedules, offering patients better alternatives. However, drawbacks with the use of DMTs include their increasing cost and formulary restrictions.

CONCLUSION

The treatment landscape of MS has significantly changed over the past 2 decades, and the introduction of newer classes of DMTs provides an opportunity for pharmacists to play an important role in the management of this patient population.

Epidemiology of progressive multifocal leukoencephalopathy in Japan and effectiveness of mefloquine: A retrospective analysis of a nationwide inpatient database

INTRODUCTION

Progressive multifocal leukoencephalopathy (PML) is an infrequent yet devastating neurological infection that arises in immunocompromised patients. The epidemiological features of PML in Japan and its evolution in recent years remain unclear. There are no established treatments that directly target PML. Although mefloquine has shown in vitro activity against JC virus, its clinical effectiveness has not been confirmed in population-level studies.

METHODS

We retrospectively analyzed the admission data of patients with PML recorded in the Diagnosis Procedure Combination (DPC) database from fiscal year 2010 to 2020 (11 years). Descriptive statistics were used to illustrate the epidemiological features. Changes in the frequency of PML admission, underlying diseases, and in-hospital mortality over time were also examined. Furthermore, we evaluated the effectiveness of mefloquine in improving activities of daily living at discharge using propensity score matching.

RESULTS

We identified 610 PML cases diagnosed by the treating physicians, which may include possible PML. Among them, 419 were first-time admissions. The median age at admission was 62.0 years, and 62.8% were men. HIV was the most common underlying condition, accounting for 22.9% of cases, followed by hematologic malignancies (18.4%), and autoimmune diseases (17.9%). Over the study period, the frequency of PML admissions showed an increasing trend, whereas the in-hospital mortality rate showed a decreasing trend. The effectiveness of mefloquine was not confirmed.

CONCLUSIONS

The results of this study will help clarify and update the clinical picture of PML in Japan. The DPC database was shown to be useful tool for epidemiological research on rare infectious disease such as PML.

Cerebellar Progressive Multifocal Leukoencephalopathy Mimicking Anti-Yo-Antibody-Associated Rapidly Progressive Cerebellar Syndrome

A 58-year-old woman with a history of systemic lupus erythematosus (SLE) who was taking prednisolone and mycophenolate mofetil presented with gait disturbances that progressively worsened over a period of 3 months. Her blood test and cerebrospinal fluid (CSF) examination results did not indicate active SLE. Initial brain magnetic resonance imaging (MRI) revealed a small spotty lesion in the left cerebellar peduncle. The clinical course was consistent with rapidly progressive cerebellar syndrome (RPCS), which sometimes involves neuronal antibodies. The line blot assay detected anti-Yo antibodies, but no malignancy was found. Immunohistological techniques using rat brain sections yielded a negative result for anti-Yo antibodies. The second MRI revealed a focal lesion and surrounding spotty lesion in the left cerebellar peduncle, which was consistent with the punctate pattern observed in progressive multifocal leukoencephalopathy (PML). The CSF JCV-DNA test indicated the presence of cerebellar PML. Immunosuppressants were reduced, and mefloquine and mirtazapine were initiated. After approximately 2 years and 1 month, the CSF JCV-DNA results became negative. Cerebellar PML may exhibit a clinical course that is consistent with RPCS. The punctate pattern should be recognized as an early manifestation of PML. The CSF JCV-DNA copy number may serve as a useful indicator of PML stabilization.

Position of Cladribine Tablets in the Management of Relapsing-Remitting Multiple Sclerosis: An Expert Narrative Review From the United Arab Emirates

The use of immune reconstitution therapies (IRT) in patients with relapsing-remitting multiple sclerosis (RRMS) is associated with a prolonged period of freedom from relapses in the absence of continuously applied therapy. Cladribine tablets is a disease-modifying treatment (DMT) indicated for highly active relapsing multiple sclerosis (MS) as defined by clinical or imaging features. Treatment with cladribine tablets is effective and well tolerated in patients with active MS disease and have a low burden of monitoring during and following treatment. In this article, an expert group of specialist neurologists involved in the care of patients with MS in the United Arab Emirates provides their consensus recommendations for the practical use of cladribine tablets according to the presenting phenotype of patients with RRMS. The IRT approach may be especially useful for patients with highly active MS insufficiently responsive to treatment with a first-line DMT, those who are likely to adhere poorly to a continuous therapeutic regimen, treatment-naïve patients with high disease activity at first presentation, or patients planning a family who are prepared to wait until at least 6 months after the end of treatment. Information available to date does not suggest an adverse interaction between cladribine tablets and COVID-19 infection. Data are unavailable at this time regarding the efficacy of COVID-19 vaccination in patients treated with cladribine tablets. Robust immunological responses to COVID-19 infection or to other vaccines have been observed in patients receiving this treatment, and treatment with cladribine tablets per se should not represent a barrier to this vaccination.

Rituximab for people with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is the most common neurological cause of disability in young adults. Off-label rituximab for MS is used in most countries surveyed by the International Federation of MS, including high-income countries where on-label disease-modifying treatments (DMTs) are available.  OBJECTIVES: To assess beneficial and adverse effects of rituximab as 'first choice' and as 'switching' for adults with MS.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and trial registers for completed and ongoing studies on 31 January 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and controlled non-randomised studies of interventions (NRSIs) comparing rituximab with placebo or another DMT for adults with MS.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. We used the Cochrane Collaboration's tool for assessing risk of bias. We rated the certainty of evidence using GRADE for: disability worsening, relapse, serious adverse events (SAEs), health-related quality of life (HRQoL), common infections, cancer, and mortality. We conducted separate analyses for rituximab as 'first choice' or as 'switching', relapsing or progressive MS, comparison versus placebo or another DMT, and RCTs or NRSIs.

MAIN RESULTS

We included 15 studies (5 RCTs, 10 NRSIs) with 16,429 participants of whom 13,143 were relapsing MS and 3286 progressive MS. The studies were one to two years long and compared rituximab as 'first choice' with placebo (1 RCT) or other DMTs (1 NRSI), rituximab as 'switching' against placebo (2 RCTs) or other DMTs (2 RCTs, 9 NRSIs). The studies were conducted worldwide; most originated from high-income countries, six from the Swedish MS register. Pharmaceutical companies funded two studies. We identified 14 ongoing studies. Rituximab as 'first choice' for relapsing MS Rituximab versus placebo: no studies met eligibility criteria for this comparison. Rituximab versus other DMTs: one NRSI compared rituximab with interferon beta or glatiramer acetate, dimethyl fumarate, natalizumab, or fingolimod in active relapsing MS at 24 months' follow-up. Rituximab likely results in a large reduction in relapses compared with interferon beta or glatiramer acetate (hazard ratio (HR) 0.14, 95% confidence interval (CI) 0.05 to 0.39; 335 participants; moderate-certainty evidence). Rituximab may reduce relapses compared with dimethyl fumarate (HR 0.29, 95% CI 0.08 to 1.00; 206 participants; low-certainty evidence) and natalizumab (HR 0.24, 95% CI 0.06 to 1.00; 170 participants; low-certainty evidence). It may make little or no difference on relapse compared with fingolimod (HR 0.26, 95% CI 0.04 to 1.69; 137 participants; very low-certainty evidence). The study reported no deaths over 24 months. The study did not measure disability worsening, SAEs, HRQoL, and common infections. Rituximab as 'first choice' for progressive MS One RCT compared rituximab with placebo in primary progressive MS at 24 months' follow-up. Rituximab likely results in little to no difference in the number of participants who have disability worsening compared with placebo (odds ratio (OR) 0.71, 95% CI 0.45 to 1.11; 439 participants; moderate-certainty evidence). Rituximab may result in little to no difference in recurrence of relapses (OR 0.60, 95% CI 0.18 to 1.99; 439 participants; low-certainty evidence), SAEs (OR 1.25, 95% CI 0.71 to 2.20; 439 participants; low-certainty evidence), common infections (OR 1.14, 95% CI 0.75 to 1.73; 439 participants; low-certainty evidence), cancer (OR 0.50, 95% CI 0.07 to 3.59; 439 participants; low-certainty evidence), and mortality (OR 0.25, 95% CI 0.02 to 2.77; 439 participants; low-certainty evidence). The study did not measure HRQoL. Rituximab versus other DMTs: no studies met eligibility criteria for this comparison. Rituximab as 'switching' for relapsing MS  One RCT compared rituximab with placebo in relapsing MS at 12 months' follow-up. Rituximab may decrease recurrence of relapses compared with placebo (OR 0.38, 95% CI 0.16 to 0.93; 104 participants; low-certainty evidence). The data did not confirm or exclude a beneficial or detrimental effect of rituximab relative to placebo on SAEs (OR 0.90, 95% CI 0.28 to 2.92; 104 participants; very low-certainty evidence), common infections (OR 0.91, 95% CI 0.37 to 2.24; 104 participants; very low-certainty evidence), cancer (OR 1.55, 95% CI 0.06 to 39.15; 104 participants; very low-certainty evidence), and mortality (OR 1.55, 95% CI 0.06 to 39.15; 104 participants; very low-certainty evidence). The study did not measure disability worsening and HRQoL.  Five NRSIs compared rituximab with other DMTs in relapsing MS at 24 months' follow-up. The data did not confirm or exclude a beneficial or detrimental effect of rituximab relative to interferon beta or glatiramer acetate on disability worsening (HR 0.86, 95% CI 0.52 to 1.42; 1 NRSI, 853 participants; very low-certainty evidence). Rituximab likely results in a large reduction in relapses compared with interferon beta or glatiramer acetate (HR 0.18, 95% CI 0.07 to 0.49; 1 NRSI, 1383 participants; moderate-certainty evidence); and fingolimod (HR 0.08, 95% CI 0.02 to 0.32; 1 NRSI, 256 participants; moderate-certainty evidence). The data did not confirm or exclude a beneficial or detrimental effect of rituximab relative to natalizumab on relapses (HR 1.0, 95% CI 0.2 to 5.0; 1 NRSI, 153 participants; very low-certainty evidence). Rituximab likely increases slightly common infections compared with interferon beta or glatiramer acetate (OR 1.71, 95% CI 1.11 to 2.62; 1 NRSI, 5477 participants; moderate-certainty evidence); and compared with natalizumab (OR 1.58, 95% CI 1.08 to 2.32; 2 NRSIs, 5001 participants; moderate-certainty evidence). Rituximab may increase slightly common infections compared with fingolimod (OR 1.26, 95% CI 0.90 to 1.77; 3 NRSIs, 5187 participants; low-certainty evidence). It may make little or no difference compared with ocrelizumab (OR 0.02, 95% CI 0.00 to 0.40; 1 NRSI, 472 participants; very low-certainty evidence). The data did not confirm or exclude a beneficial or detrimental effect of rituximab on mortality compared with fingolimod (OR 5.59, 95% CI 0.22 to 139.89; 1 NRSI, 136 participants; very low-certainty evidence) and natalizumab (OR 6.66, 95% CI 0.27 to 166.58; 1 NRSI, 153 participants; very low-certainty evidence). The included studies did not measure SAEs, HRQoL, and cancer.

AUTHORS' CONCLUSIONS

For preventing relapses in relapsing MS, rituximab as 'first choice' and as 'switching' may compare favourably with a wide range of approved DMTs. A protective effect of rituximab against disability worsening is uncertain. There is limited information to determine the effect of rituximab for progressive MS.  The evidence is uncertain about the effect of rituximab on SAEs. They are relatively rare in people with MS, thus difficult to study, and they were not well reported in studies. There is an increased risk of common infections with rituximab, but absolute risk is small.  Rituximab is widely used as off-label treatment in people with MS; however, randomised evidence is weak. In the absence of randomised evidence, remaining uncertainties on beneficial and adverse effects of rituximab for MS might be clarified by making real-world data available.

Risk of Progressive Multifocal Leukoencephalopathy in Multiple Sclerosis Patient Treated With Natalizumab: A Systematic Review

Natalizumab, a monoclonal antibody acting on alpha4 integrin receptors, is frequently used to treat multiple sclerosis patients. The biggest downside is the risk of development of progressive multifocal leukoencephalopathy, an immune-related condition affecting mainly the central nervous system. The presence of the John Cunningham virus (JCV) and its reactivation is an important factor in the development of progressive multifocal leukoencephalopathy (PML). This study highlights its different proposed mechanism and risk factors strongly related to natalizumab-induced progressive multifocal leukoencephalopathy. The pieces of literature will also be reviewed to look for a relation between the JCV and natalizumab-induced progressive multifocal leukoencephalopathy in multiple sclerosis treated patients.

The articles were searched from three databases and reviewed systematically. The inclusion criteria for this study were patients aged 20-50 years, English language paper, full-text availability, and human studies, whereas articles on patients with AIDS and cancer-related disease prior to natalizumab treatment were excluded.

Out of 6531 articles identified after applying the search strategy on three main databases PubMed, Google Scholar, and ResearchGate, a total of 32 articles were finalized for the review. This study follows the guidelines listed in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist 2009. The data collected from these finalized articles were pertaining to the risk factor related to natalizumab induced progressive multifocal leukoencephalopathy and the mechanism related to its pathogenesis. 

Natalizumab is known to have the potential to cause progressive multifocal leukoencephalopathy in treated patients; here, we evaluate a close relationship of its related risk factors. The articles studied exhibit a close relationship between the length of natalizumab treatment and the presence of the JCV before infusion of natalizumab. From our analysis, it seems that the mechanism related to natalizumab-induced PML is strongly related to antigen-specific T cells and its effects. The frequency of monitoring and vigilance on the management of patients treated with natalizumab will help detect progressive multifocal leukoencephalopathy.

Atypical Multiple Sclerosis Lesions or Progressive Multifocal Leukoencephalopathy Lesions: That Is the Question

Progressive multifocal leukoencephalopathy (PML) is a serious infective disease of the central nervous system that may occur in case of severe immunosuppression or after some treatment for multiple sclerosis (MS) with natalizumab, dimethyl fumarate, and fingolimod. In these case reports, we highlight the importance of differential diagnosis between PML and MS lesions in order to provide rapidly the best treatment option, by discussing the finding of brain (magnetic resonance imaging) MRI suggestive for PML in 2 MS patients, one treated with dimethyl fumarate and the other during natalizumab withdrawal. In both cases, although brain MRI was highly suggestive for PML, the detection of John Cunningham virus-DNA copies in cerebrospinal fluid resulted in negative result. These case reports illustrate the diagnostic process in case of suspected PML, as both patients were diagnosed with suspected PML during a routine brain MRI control, and highlights the importance of providing a strict brain MRI follow-up during dimethyl fumarate treatment, although only a few cases of PML during this therapy have been detected, and during natalizumab suspension phase. In clinical practice, in case of a radiologically suspected case of PML, although not confirmed by the cerebrospinal fluid analysis, the best approach could be to perform a close radiological and clinical monitoring before starting a new MS therapy.

[Comparison of the clinical benefits of second-line drugs modifying the course of multiple sclerosis]

This review aims at describing clinical benefits and characteristics of the main highly effective disease modifying drugs (DMD) for multiple sclerosis (MS): alemtuzumab, cladribine tablets, ocrelizumab, natalizumab, fingolimod based on the efficacy and safety. The authors highlight that all MS DMDs have certain benefits and features that shall be considered in prescribing pharmacotherapy. Cladribine in tablets are comparable by the efficacy to other modern highly effective second-line drugs, have a high level of evidence and a favorable safety profile, as well as the most preferred benefit/risk ratio among other MS DMDs indicated for the treatment of highly active MS, which offers an advantage to the drug. The use of cladribine in tablets will contribute to further study of the efficacy and safety of this highly efficient drug for MS treatment.

Precision medicine in the multiple sclerosis clinic: Selecting the right patient for the right treatment

Multiple sclerosis (MS) is a chronic, inflammatory disease of the central nervous system (CNS), affecting patients of all ages, causing neurologic disability if inadequately treated. Some patients have a relatively benign disease course without significant disability after decades, while a more aggressive course ensues in others and disability progression occurs after only several years. Certain risk factors confer a higher chance of a patient having aggressive MS. Currently over 15 disease-modifying treatments (DMTs) are approved for MS with different efficacy and safety profiles. Deciding which DMT to use in a specific patient requires a careful analysis of a patient’s disease course for high-risk factors for early progression, consideration of the efficacy and safety profile for potential therapy, as well as understanding of a patient’s lifestyle and expectations. The integration of these factors is the art of precision medicine, a necessary practice in the treatment of patients with MS.

Prevalence of Anti-JC Virus (JCV) Antibodies in the Multiple Sclerosis (MS) Population in Cyprus: A Retrospective Study

Background and Purpose

Progressive multifocal leukoencephalopathy (PML) is a debilitating disease of the central nervous system caused by the ubiquitous polyomavirus JC (JCV) in immunocompromised hosts. In recent years, a new subpopulation of patients at risk for PML has emerged, due to the growing use of immunomodulatory or immunosuppressive therapies in autoimmune diseases such as multiple sclerosis (MS). The anti-JCV antibody index is used as a stratification tool in assessing the risk of developing PML. The objective of this study was to retrospectively describe the prevalence of anti-JCV antibodies in the MS population in Cyprus.

Methods

We retrospectively collected the demographics of 214 MS patients in Cyprus who were screened for anti-JCV antibodies using the STRATIFY JCV™ assay between September 2011 and June 2018. Logistic regression analysis was used to examine the effect of demographic variables on seropositivity, and bivariate tests were used to assess the association between demographic characteristics and JCV AI index.

Results

A total of 214 MS patients in Cyprus were tested. Overall anti-JCV antibody prevalence was 45.8% (95% confidence interval 37.2%–55.8%). We could not establish a significant association between seropositivity and increasing age or sex. In the subgroup analysis of natalizumab-treated patients, the annual seroconversion rate was 4.5%.

Conclusions

Overall seroprevalence of anti-JCV antibodies in MS patients in Cyprus using the STRATIFY JCV assay was lower than the worldwide reported mean. Although previously reported, in our study, the anti-JCV antibody seropositivity was not associated with increasing age or sex.

Insight into the mechanism of action of dimethyl fumarate in multiple sclerosis

Dimethyl fumarate (DMF) is an oral, disease-modifying agent for the treatment of relapsing-remitting multiple sclerosis (RRMS). However, details regarding its mode of action are still emerging. It is believed that the mode of action of DMF involves both nuclear factor erythroid-derived 2-related factor (Nrf2)-dependent and independent pathways, which lead to an anti-inflammatory immune response due to type II myeloid cell and Th2 cell differentiation and neuroprotection. In this review, we will focus on the molecular and signaling effects of DMF that lead to changes in peripheral immune cell composition and function, alteration in CNS cell-specific functions, and effect on the blood-brain barrier.