JC virus seroprevalence and seroconversion in multiple sclerosis cohort: A Middle-Eastern study

Consensus recommendations for diagnosis and treatment of Multiple Sclerosis: 2023 revision of the MENACTRIMS guidelines

With evolving diagnostic criteria and the advent of new oral and parenteral therapies for Multiple Sclerosis (MS), most current diagnostic and treatment algorithms need revision and updating. The diagnosis of MS relies on incorporating clinical and paraclinical findings to prove dissemination in space and time and exclude alternative diseases that can explain the findings at hand. The differential diagnostic workup should be guided by clinical and laboratory red flags to avoid unnecessary tests. Appropriate selection of MS therapies is critical to maximize patient benefit. The current guidelines review the current diagnostic criteria for MS and the scientific evidence supporting treatment of acute relapses, radiologically isolated syndrome, clinically isolated syndrome, relapsing remitting MS, progressive MS, pediatric cases and pregnant women. The purpose of these guidelines is to provide practical recommendations and algorithms for the diagnosis and treatment of MS based on current scientific evidence and clinical experience.

JC Virus Seroprevalence and JCVAb Index in Polish Multiple Sclerosis Patients Treated with Immunomodulating or Immunosuppressive Therapies

The use of a highly-effective treatment for multiple sclerosis (MS) is associated with a severe risk of developing complications, such as progressive multifocal leukoencephalopathy (PML) caused by the John Cunningham virus (JCV). The aim of this study was to evaluate the correlation between anti-JCV Ab seroprevalence, anti-JCV AI, demographic and clinical factors as well as the type of therapy used in the Polish MS population. This is a multicentre, prospective and cross-sectional study involving 1405 MS patients. The seroprevalence of anti-JCV Ab and anti-JCV AI levels as well as AI categories were analysed with the use of a second-generation two-step ELISA test (STRATIFY JCV DxSelect). The overall prevalence of anti-JCV Ab was 65.8%. It was shown that seroprevalence increases with the patient's age. The seroprevalence was significantly associated with the treatment type, and the highest values (76%) were obtained from immunosuppressant-treated patients. Overall, 63.3% of seropositive patients had an antibody index (AI) level of >1.5. In the seropositive patient group, the mean AI level amounted to 2.09. Similarly to the seroprevalence, AI levels correlated with the patient's age; AI level for patients above 40 years old and from subsequent age quintiles plateaued, amounting to at least 1.55. Patients treated with immunosuppressants and immunomodulatory drugs obtained the highest (1.67) and lowest (1.35) AI levels, respectively. Of the immunosuppressants used, the highest mean AI levels were observed in mitoxantrone and cladribine groups, amounting to 1.75 and 1.69, respectively. In patients treated with immunomodulatory drugs, the lowest AI levels were observed in the dimethyl fumarate (DMF) group (1.11). The seroprevalence rate in the Polish MS population is one of the highest in Europe. The majority of seropositive patients had an anti-JCV Ab level qualifying them for a high-risk category. The highest mean AI levels are observed in patients receiving immunosuppressants, especially mitoxantrone and cladribine. Patients receiving immunomodulatory drugs have lower AI levels compared to treatment-naïve subjects, especially when treated with DMF. Further studies, especially longitudinal studies, are required to determine the impact of MS drugs on the seroprevalence of anti-JCV Ab and AI levels.

High rates of JCV seroconversion in a large international cohort of natalizumab-treated patients

Aims:

To retrospectively assess factors associated with John Cunningham virus (JCV) seroconversion in natalizumab-treated patients.

Background:

Natalizumab is highly effective for the treatment of relapsing–remitting multiple sclerosis (RRMS), but its use is complicated by opportunistic JCV infection. This virus can result in progressive multifocal leukoencephalopathy (PML). Serial assessment of JCV serostatus is mandated during natalizumab treatment.

Methods:

Patients treated with natalizumab for RRMS at six tertiary hospitals in Melbourne, Australia (n = 865) and 11 MS treatment centres in Brazil (n = 136) were assessed for change in JCV serostatus, duration of exposure to natalizumab and prior immunosuppression. Sensitivity analyses examined whether sex, age, tertiary centre, prior immunosuppression or number of JCV tests affected time to seroconversion.

Results:

From a cohort of 1001 natalizumab-treated patients, durable positive seroconversion was observed in 83 of 345 initially JCV negative patients (24.1%; 7.3% per year). Conversely, 16 of 165 initially JCV positive patients experienced durable negative seroconversion (9.7%; 3.8% per year). Forty patients (3.9%) had fluctuating serostatus. Time-to-event analysis did not identify a relationship between JCV seroconversion and duration of natalizumab exposure. Prior exposure to immunosuppression was not associated with an increased hazard of positive JCV seroconversion. Male sex was associated with increased JCV seroconversion risk [adjusted hazard ratio 2.09 (95% confidence interval 1.17–3.71) p = 0.012].

Conclusion:

In this large international cohort of natalizumab-treated patients we observed an annual durable positive seroconversion rate of 7.3%. This rate exceeds that noted in registration and post-marketing studies for natalizumab. This rate also greatly exceeds that predicted by epidemiological studies of JCV seroconversion in healthy populations. Taken together, our findings support emerging evidence that natalizumab causes off-target immune changes that may be trophic for JCV seroconversion. In addition, male sex may be associated with increased positive JCV seroconversion.

JC Virus Seroprevalence and JCVAb Index in Polish Multiple Sclerosis Treatment-Naïve Patients

Multiple sclerosis (MS) treatment with new agents is associated with the risk of the development of progressive multifocal leukoencephalopathy (PML). The seropositivity and a high index of anti-John Cunningham virus (JCV) antibodies are some of the risk factors for PML development. The aim of this study was to assess the seroprevalence of anti-JCVAb and JCVAb index (AI), as well as its correlations with demographic and clinical characteristics in treatment-naïve Polish MS patients. This is a multicenter, prospective, and cross-sectional study involving 665 MS patients. The overall prevalence of anti-JCVAb was 65.3%, while 63.1% of seropositive patients had an index level of >1.5. The seroprevalence was shown to increase along with the patient's age. Except for age, the prevalence of anti-JCVAb was not associated with demographic or clinical data. No correlations between the index levels and the demographic or clinical data were observed. In Poland, the seroprevalence of anti-JCVAb in treatment-naïve MS patients is one of the highest in Europe. The majority of seropositive patients had an anti-JCV antibody level denoting a high-risk category. This means that we need further studies to be conducted on the individualization of MS treatment in order to provide patients with an appropriate therapeutic safety level.

John Cunningham Virus Status, Seroconversion Rate, and the Risk of Progressive Multifocal Leukoencephalopathy in Polish John Cunningham Virus-Seronegative Patients with Relapsing-Remitting Multiple Sclerosis

INTRODUCTION

Presence of anti-JC-virus antibodies (JCVAbs) is associated with the increased risk of natalizumab (NAT)-related progressive multifocal leukoencephalopathy (PML). Little is known about seroconversion rate and time to seroconversion in relapsing-remitting multiple sclerosis (RRMS) patients treated with NAT in Poland. The aim of the study was to assess the true risk of PML, seroconversion rate, and time to seroconversion in all JCVAb-negative RRMS patients treated with NAT in Poland.

METHODS

Demographic and clinical data of all Polish RRMS patients treated with NAT reimbursed by National Health Fund (NFZ) were prospectively collected in electronic files using the Therapeutic Programme Monitoring System provided by NFZ. The assessment of JCVAb presence (without collection of JCVAb index value) in serum (Unilabs, STRATIFY JCV: anti-JCV antibody ELISA) was done at the beginning of therapy and then repeated every 6 months. The maximum follow-up time was 4 years. In Poland, since 2013, according to the NFZ drug program guidance, only patients with negative JCVAb test have started treatment with NAT.

RESULTS

In all Polish multiple sclerosis centers, 210 negative JCVAb RRMS patients with at least 9 (±3) months of observation (146 females, 64 males, and the median age at baseline: 33 years) were included in the study. During the follow-up period, JCVAb status changed from negative to positive in 34 patients (16.2%). For half of the patients, the seroconversion was diagnosed 1 year after starting NAT treatment. In 4 patients (1.9%) during follow-up, JCVAb status changed again from positive to negative. In Poland, before establishment of NFZ drug program, 4 cases of PML in patients treated with NAT in clinical trials were diagnosed. In the NFZ drug program, since 2013, no patient treated with NAT has been diagnosed with PML.

CONCLUSIONS

NAT therapy in JCV-seronegative RRMS patients is safe and results in the absence of PML cases. In Poland, JCV seroconversion rate is similar to that observed in other European countries.

Prevalence of Anti-JC Virus Antibody Seropositivity in Patients with Multiple Sclerosis: A Systematic Review and Meta-Analysis

BACKGROUND

The John Cunningham virus (JCV) is the causative agent of progressive multifocal leukoencephalopathy. Anti-JCV antibody seropositivity is an important consideration in patients with multiple sclerosis (MS). The reported prevalence of JCV in MS patients has been conflicting.

OBJECTIVE

We aimed to conduct a systematic review and meta-analysis to estimate the pooled prevalence of anti-JCV antibody seropositivity in cases with MS.

METHODS

We searched PubMed, Scopus, EMBASE, CINAHL, Web of Science, Ovid, ProQuest, Google Scholar, and gray literature including reference of included studies, and conference abstracts which were published up to April 2019. Two independent researchers independently assessed the articles.

RESULTS

The literature search found 181 articles. After eliminating duplicates, reviews, case reports, and trials, 15 articles remained. Finally, 8 articles were included for the final analysis (from Asia, Europe, the USA, and Canada). In total, 16,041 MS cases were analyzed. The prevalence of anti-JCV antibody seropositivity varied between 40 and 80%, and the pooled estimate was calculated as 60% (95% CI: 56-64%), though with significant heterogeneity (I2 = 95%, p = 0.01).

CONCLUSION

The prevalence of anti-JCV antibody seropositivity is variable among MS patients in different countries, and the pooled estimate showed that this is 60% overall.

Risk of Progressive Multifocal Leukoencephalopathy in the Combination Antiretroviral Therapy Era in the French Hospital Database on Human Immunodeficiency Virus (ANRS-C4)

Background

Risk factors for progressive multifocal leukoencephalopathy (PML) in individuals with human immunodeficiency virus (HIV) infection are poorly documented in the era of combination antiretroviral therapy (cART).

Methods

We studied HIV-1-infected individuals aged ≥15 years who had no history of PML and were prospectively followed up between 1997 and 2011 in the French Hospital Database on HIV (FHDH-ANRS CO4) cohort. Cox models were used to calculate adjusted hazard ratios (HRs), focusing on sub-Saharan origin, suggested to be protective, and recent cART initiation, potentially associated with an increased risk of PML.

Results

PML developed in 555 individuals, in 57 during the first 6 months of cART. From 1997-2000 to 2009-2011, the incidence fell from 1.15 (95% confidence interval [CI], .98-1.31) to 0.49 (.37-.61) per 1000 person-years. Sub-Saharan African origin had no clear influence (HR, 0.80; 95% CI, .58-1.11). Compared with men who have sex with men, injection drug users (IDUs) were at higher risk (HR, 1.80 [95% CI, 1.32-2.45] for male and 1.68 [1.13-2.48] for female IDUs). When IDUs were excluded, hepatitis C virus seropositivity was associated with an increased risk (HR, 1.40; 95% CI, 1.02-1.93). Compared with no cART initiation, initiation <6 months previously was associated with PML onset (HR, 4.91; 95% CI, 2.42-9.95).

Conclusions

Recent cART initiation is associated with an increased risk of PML, as are injection drug use and hepatitis C virus seropositivity. Sub-Saharan African origin had no protective effect.

Consensus recommendations for the diagnosis and treatment of multiple sclerosis: 2019 revisions to the MENACTRIMS guidelines

With evolving diagnostic criteria and the advent of new oral and parenteral therapies for MS, most current diagnostic and treatment algorithms need revision and updating. The diagnosis of MS relies on incorporating clinical and paraclinical findings to prove dissemination in space and in time, and exclude alternative diseases that can explain the findings at hand. The differential diagnostic workup should be guided by clinical and laboratory red flags to avoid unnecessary tests. Appropriate selection of multiple sclerosis (MS) therapies is critical to maximize patient benefit. The current guidelines review the scientific evidence supporting treatment of acute relapses, radiologically isolated syndrome, clinically isolated syndrome, relapsing remitting MS, and progressive MS. The purpose of these guidelines is to provide practical recommendations and algorithms for the diagnosis and treatment of MS based on current scientific evidence and clinical experience.

Incidence of seroconversion and sero-reversion in patients with multiple sclerosis (MS) who had been treated with natalizumab: A systematic review and meta-analysis

BACKGROUND

Natalizumab is a medication of choice for some patients with relapsing remitting (RR) form of multiple sclerosis (MS). John Cunningham virus (JCV) antibody status is important in cases who are treating with natalizumab. Different studies reported various rates of seroconversion and sero-reversion in patients who had been treated with natalizumab. As there is no systematic review reporting incidence of seroconversion and seroreversion in MS cases who were treated with natalizumab, we aimed to conduct this systematic review and meta-analysis to find pooled incidence of seroconversion and seroreversion in MS cases who were treated with natalizumab.

METHODS

PubMed, Scopus, EMBASE, CINAHL, Web of Science, Ovid, and google scholar were systematically searched. We also searched the gray literature including references from included studies, and conference abstracts which were published up to April 2019.

RESULTS

The incidence of seroconversion was reported between 6% and 41% and the incidence of seroreversion was reported between 1% and 11%. The pooled estimate of seroconversion incidence was 19% (95% CI: 13%-25%) (I² = 96.8%, P < 0.001) and the pooled estimate of seroreversion incidence was 5% (95% CI: 3%-8%) (I² = 72.2%, P < 0.001). Subgroup analysis by considering the country of the origin showed that the pooled incidence of seroconversion incidence during the studies was 6% in Asian countries and 21% in European/American countries. The incidence difference between subgroups was significant (p < 0.001).

CONCLUSION

Incidence of seroconversion in MS patients who had been treated with natalizumab is higher in European/American countries than Asian countries.

JC virus antibodies in Portuguese multiple sclerosis patients: JUSTIFY study results

OBJECTIVE

To confirm anti-JC virus (JCV) antibody seroprevalence in Portuguese patients with relapsing-remitting multiple sclerosis (RRMS) and to determine their anti-JCV antibody index.

METHODS

JUSTIFY was a retrospective, multicentre study that included 655 RRMS patients tested at least once with the anti-JCV antibody assay STRATIFY JCV DxSelect. Demographic data, multiple sclerosis history and results of the anti-JCV antibody test were collected, along with physicians' reasons for requesting the test and the impact of the results.

RESULTS

Overall anti-JCV antibody seroprevalence was 60.8% (95% confidence interval, 56.9-64.5). Seroprevalence was associated with higher age (P = .030) and was lower in natalizumab-treated patients (P < .001). The mean anti-JCV antibody index of immunosuppressant-naive patients was 1.5 ± 1.3 (n = 378). The main reasons for performing the test were clinical characterization (35.5%) and medication change (26.2%). In patients who switched treatments (n = 109), fingolimod (47.7%) and natalizumab (26.6%) were the most commonly chosen new treatments.

CONCLUSIONS

The study confirmed the high anti-JCV antibody prevalence in Portuguese RRMS patients and its association with age. These data can be used to better understand the benefit-risk profile of natalizumab treatment in Portuguese patients and to support progressive multifocal leukoencephalopathy risk management strategies.

Conversion and reversion of anti-John Cunningham virus antibody serostatus: A prospective study

INTRODUCTION

Determination of antibodies against the John Cunningham virus (JCV) is an important tool for risk stratification in Natalizumab-treated multiple sclerosis (MS) patients. Six-monthly testing has been suggested for anti-JCV antibody negative patients and patients with low antibody index in order to detect changes of serostatus. We conducted a prospective study with predefined testing intervals in order to investigate the predictability of anti-JCV antibody status and the intervals for repetitive testing.

METHODS

Our study included 109 patients at the MS Clinic of the Departments of Neurology, Medical Universities of Innsbruck and Salzburg. Blood withdrawals were performed at five time points: baseline, month 1, 3, 6, and 12. Patients' sera were sent to Unilabs, Copenhagen, Denmark, where anti-JCV antibodies were tested by a two-step enzyme-linked immunosorbent assay. Qualitative (negative/positive) and quantitative results (anti-JCV antibody index) were used for statistical analyses.

RESULTS

In our cohort, 52.3% of the patients were positive for anti-JCV antibodies at baseline, with a significant correlation with age, but no association with sex or prior disease-modifying therapy. Seven patients converted and reverted from negative to positive status and vice versa around the cut-off index of 0.4, but no patient showed a permanent seroconversion from negative to highly positive anti-JCV antibody status.

CONCLUSION

Long-term anti-JCV antibody status, including seroconverters/-reverters around the cut-off index, is highly predictable by testing three times within short intervals, however, we cannot suggest clearly defined intervals for repetitive testing. The rate of real seroconverters, i.e., new infections with JCV, per year seems lower than previously described.

Serological profile of John Cunningham virus (JCV) in patients with multiple sclerosis

Treatment options for multiple sclerosis (MS) have changed over the last few years, bringing about a new category of drugs with more efficient profiles. However, these drugs have come with a whole new profile of potential adverse events that neurologists have to learn well and quickly. One of the most feared complications of these MS treatments is progressive multifocal leukoencephalopathy caused by the reactivation of the John Cunningham virus (JCV).

OBJECTIVE

To identify the serologic profile of JCV in patients with MS.

METHODS

Data on serum antibodies for JCV were obtained using the enzyme-linked immunosorbent assay provided by the STRATIFY-JCV program.

RESULTS

A total of 1,501 blood tests were obtained from 1,102 patients with MS. There were 633 patients (57.1%) who were positive for antibodies for JCV and 469 patients who were negative (42.9%). Twenty-three patients became positive after initially having negative JCV antibody status. The rate of seroconversion was 18.5% over 22 months.

CONCLUSION

The JCV serologic profile and seroconversion in Brazilian patients were similar to those described in other countries.

Cost-effectiveness of alemtuzumab and natalizumab for relapsing-remitting multiple sclerosis treatment in Iran: decision analysis based on an indirect comparison

BACKGROUND

Alemtuzumab and natalizumab are approved as second-line therapies for relapsing-remitting multiple sclerosis (RRMS) patients in Iran who have shown an inadequate response to other disease-modifying therapy (DMT). In the absence of head-to-head trials, evaluations based on decision analytic modeling may be a suitable alternative to compare alemtuzumab and natalizumab in RRMS.

PURPOSE

To evaluate the cost-effectiveness of alemtuzumab compared with natalizumab in RRMS in Iran, based on an indirect comparison of clinical trial data.

METHODS

A cost-utility analysis was conducted using a cohort-based Markov model to analyze cost-utility in a cohort of 1,000 RRMS patients treated with alemtuzumab or natalizumab who had failed at least one previous DMT. Costs were measured in 2018 US Dollars, and were estimated from both the societal and National Healthcare Service (NHS) perspective over a 20-year time horizon in Iran. One-way deterministic sensitivity analyses were carried out to investigate the impact of individual variables on model results.

RESULTS

Alemtuzumab dominated natalizumab in both NHS and societal perspective analyses. From the NHS perspective, the total discounted costs per patient were estimated at $147,417 and $150,579 for alemtuzumab and natalizumab, respectively, over 20 years. The discounted quality-adjusted life years were estimated to be 7.07 and 6.05, respectively. Results were similar for the societal perspective analysis. Results were most sensitive to acquisition costs and the time horizon, while no sensitivity was observed for Expanded Disability Status Scale (EDSS) health-states utility, relapse relative risk, adverse event or EDSS-related costs, and laboratory/monitoring costs.

CONCLUSION

Alemtuzumab was dominant in the treatment of RRMS compared with natalizumab due to lower total cost, greater efficacy and slowing of disease progression, and lower rate of relapses over a 20-year time horizon in Iran. Comparative head-to-head trials and long-term follow-up are needed to confirm these results.

Natalizumab versus fingolimod and dimethyl fumarate in multiple sclerosis treatment

Objective

To compare 2‐year effectiveness and discontinuation of natalizumab (NTZ) versus fingolimod (FTY) and dimethyl fumarate (DMF) in the treatment of multiple sclerosis (MS).

Methods

Patients prescribed NTZ, FTY, or DMF at the Rocky Mountain MS Center at University of Colorado were identified. Clinician‐reported data were retrospectively collected. Outcomes include a composite effectiveness measure consisting of new T2 lesion, gadolinium‐enhancing lesion, and/or clinical relapse, individual effectiveness outcomes and discontinuation over 2 years. Logistic regression was used for data analysis on patients matched by propensity scores and using ATT doubly robust weighting estimator.

Results

A total of 451, 271, and 342 patients were evaluated on NTZ, FTY, and DMF over 2 years, respectively. Patients had a mean age of 39.8 (NTZ), 42.5(FTY), and 45.8 (DMF) years; were predominantly female (76.7% NTZ; 72.0% FTY; 69.6% DMF); and had a mean MS disease duration of 11–12 years for all groups. At ≤24 months, 22.2%, 34.7%, and 33.6% experienced a new T2 lesion, gadolinium‐enhancing lesion, and/or clinical relapse on NTZ, FTY, and DMF, respectively. Using ATT doubly robust weighting estimator, FTY versus NTZ and DMF versus NTZ had an odds ratio of 2.00 (95%CI:[1.41–2.85], P < 0.001) and 2.38 [95% CI: 1.68–3.37], P < 0.001) respectively, for experiencing a new T2 lesion, gadolinium enhancing lesion, and/or clinical relapse. At ≤24 months, 32.6%, 34.3%, and 47.1% discontinued NTZ, FTY, and DMF, respectively. The majority of discontinuations were due to becoming JCV positive(12.6%) for NTZ and due to adverse events for both FTY(17%) and DMF(24.0%).

Interpretation

NTZ appears to be more effective and tolerable than FTY and DMF.

Impact of Disease-Modifying Treatments on the Longitudinal Evolution of Anti-JCV Antibody Index in Multiple Sclerosis

Background: Risk of natalizumab-related progressive multifocal leukoencephalopathy is associated with the presence of anti-JC-virus (JCV) antibodies.

Objective: To investigate the impact of disease-modifying treatments (DMT) on the longitudinal evolution of anti-JCV antibody index.

Methods: Patients with multiple sclerosis who had serum sampling at intervals of 6 ± 3 months over up to 6 years and who either started DMT (interferon-β, glatiramer acetate or natalizumab) during the observation period with at least one serum sample available before and after treatment initiation or received no DMT during the observation period were included. Anti-JCV antibody serological status and index were determined by 2-step second-generation anti-JCV antibody assay.

Results: A total of 89 patients were followed for a median time of 55.2 months. Of those, 62 (69.7%) started DMT and 27 (30.3%) were without therapy during the observation period. Variation of longitudinal anti-JCV antibody index ranged from 9 to 15% and was similar in patients with and without DMT. Applying a mixed model considering the combined effects of treatment and time as well as individual heterogeneity did not show a significant change of anti-JCV antibody index by the start of treatment with interferon-β, glatiramer acetate, or natalizumab.

Conclusion: Evaluated DMTs do not impact longitudinal anti-JCV antibody index evolution.

No Evidence for an Association between JC Polyomavirus Infection and Gastroduodenal Diseases

Background

Helicobacter pylori (HP) infection is one of the hypothesized infectious etiologies of gastric cancer (GC) and other gastroduodenal diseases. It was suggested that other infectious agents, including oncogenic viruses, may increase the risk of gastroduodenal diseases. A number of reports regarding JC polyomavirus (JCPyV) have shown that JCPyV could be implicated in colorectal cancer and gastrointestinal carcinogenesis.

Objective

The current investigation aimed to investigate whether JCPyV could have any association with the pathogenesis of gastroduodenal diseases either alone or together with HP.

Methods

A total of 237 fresh or formalin-fixed and paraffin-embedded gastroduodenal samples were examined by quantitative real-time polymerase chain reaction targeting the JCPyV large tumor antigen (LTag) oncogene, and viral load was determined as viral copy number/cell.

Results

In total, 2 out of 237 samples (0.8%) were positive for JCPyV LTag DNA. One positive sample derived from diffuse-type gastric adenocarcinoma (6.8 × 10^-3 copies/cell) and other JCPyV-positive sample obtained from a patient with gastritis (2.5 × 10^-3 copies/cell) were recorded. Both JCPyV-positive samples were negative for HP infection.

Conclusion

This study suggests no association between JCPyV infection and GC or other gastroduodenal diseases. The very low frequency of JCPyV LTag sequences in GC is an important aspect that weakens the hypothesis of the pathogenic role of JCPyV in gastric tumor induction.

Anti-JC virus antibody sera positivity and index value among patients with multiple sclerosis may be correlated with age, sex, and area of residence

Anti-JC virus (JCV) antibody index is the predictive factor of progressive multifocal leukoencephalopathy (PML) for multiple sclerosis (MS) patients treating with natalizumab. The aim of this study is to evaluate the prevalence of anti-JCV antibody positivity and index among Iranian patients who are the candidate for natalizumab and its correlation with their demographic data and previous therapies. A cross-sectional design was assessed for receiving anti-JCV antibody test results between January 2014 and December 2016. Demographic data and disease characteristics were also obtained. Statistical analysis and logistic regression were done using SPSS. Among 803 MS patients that were observed, the prevalence of anti-JCV antibody positivity was 67.9% (mean of index = 2.23 ± 1.16) and 67.6% of positive patients had an index ≥ 1.5. Males were more antibody positive than females (81.7 and 64% respectively; significance (sig.) < 0.001, OR = 2.51, CI 1.65-3.81). The rate of positivity was lower in patients under the age of 18. Patients who lived in cold regions had significantly more prevalence of positivity (Num. = 403; sig. = 0.043 and OR = 1.86; CI 1.02-3.39) and with higher rate of index ≥ 1.5 (sig. = 0.017; OR = 3.99, CI 1.79-8.88). Disease onset age between 28 and 37 years were more positive compared to 18-27 years (N = 480; sig. = 0.02; OR = 1.85, CI 1.09-3.14). Age, male gender, onset age, and cold area of residency significantly influenced anti-JCV antibody sera positivity. Only age of onset and cold area of residency were related to the index. No significant difference was observed between type, dosage, and duration of previous immunosuppressant drugs and anti-JCV antibody positivity and index value.

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%.

Anti-JCV serology during natalizumab treatment: Review and meta-analysis of 17 independent patient cohorts analyzing anti-John Cunningham polyoma virus sero-conversion rates under natalizumab treatment and differences between technical and biological sero-converters

BACKGROUND

Anti-John Cunningham virus (JCV) serology has been studied with varying results concerning longitudinal changes.

OBJECTIVES AND METHODS

Results from 17 published natalizumab-treated multiple sclerosis (MS) patient cohorts were analyzed with common parameters and subsequently verified in two large independent cohorts with 722 and 499 patients from Germany and the United States.

RESULTS

Published studies and the verification showed (1) a mean of 10.80% sero-negative patients presented with sero-status change to positivity per year; (2) patients, who sero-convert to index values <0.9, convert from near the threshold and have a high probability of reverting with time; (3) patients, who convert to index values >0.9, start with low index values; (4) while JCV sero-positive patients with low index values sometimes revert to sero-negativity, patients with high index values almost never revert; and (5) the conversion rate of natalizumab-treated patients is three to four times higher than the biological conversion by age.

CONCLUSION

JCV sero-conversion was comparable using standardized parameters and indicates influence of natalizumab on JCV immune control. Converters to low index values are probably consistently infected with JCV with varying low levels of activity, in line with their low risk to develop progressive multifocal leukoencephalopathy (PML). Patients with high index values rarely revert back to sero-negativity.

Stability and predictive value of anti-JCV antibody index in multiple sclerosis: A 6-year longitudinal study

BACKGROUND

Risk of natalizumab-related progressive multifocal leukoencephalopathy is associated with the presence of anti-JC-virus (JCV) antibodies.

OBJECTIVE

To investigate the longitudinal evolution of anti-JCV antibody index and to determine the predictive value of baseline anti-JCV antibody index for long-term stability of anti-JCV antibody status.

METHODS

MS patients from the MS centre of Medical University of Innsbruck, who had serum sampling for a time period of 4-6 years at intervals of 6±3 months, were included in this retrospective, longitudinal study. Anti-JCV antibody serological status and index were determined by 2-step second-generation anti-JCV antibody assay.

RESULTS

154 patients were included in this study. Median follow-up time was 63.7 months, with median 11 samples available per patient. At baseline, 111 (72.1%) patients were anti-JCV antibody positive. Baseline anti-JCV antibody index significantly correlated with age (R = 0.22, p = 0.005); there was no difference with respect to sex, disease duration or previously used disease-modifying treatment. During follow-up anti-JCV antibody status changed from negative to positive or vice versa in 17% of patients. In seronegative patients at baseline, baseline anti-JCV antibody index was significantly lower in those remaining seronegative at follow-up compared to those converting to seropositivity (median 0.16 vs. 0.24, p = 0.002). In seropositive patients at baseline, index was higher in those remaining seropositive compared to those reverting to seronegativity (2.6 vs. 0.45, p<10-7). Baseline anti-JCV antibody index >0.90 predicted stable positive serostatus (sensitivity 88.7%, specificity 96.5%) and <0.20 stable negative serostatus (sensitivity 61.3%, specificity 97.6%).

CONCLUSIONS

Anti-JCV antibody index remained relatively stable over 6-year follow-up with annual serostatus change of ~3%. Baseline anti-JCV antibody index predicted stable negative and stable positive JCV serostatus.

Natalizumab-associated PML

Progressive multifocal leukoencephalopathy (PML) associated with natalizumab treatment continues to be a severe problem of clinically successful therapy. This is an update of risk stratification developments and discusses the current approach to depict and calculate PML incidence and PML risk. (1) PML incidence and resulting risk used in today's clinical practice are potentially outdated and the risk for patients with prior immunosuppression might have been underestimated. (2) Risk stratification according to treatment duration epochs likely suggests lower risk due to patients stopping treatment within a given epoch. PML incidence within the complete treatment epoch is statistically lowered due to the fact that patients at the beginning of an epoch presumably have a lower PML risk than the patients at the end. Periodic risk is not accurate in assessing risk for long treatment durations. (3) The JC virus (JCV) serostatus risk factor has low specificity concerning PML prediction and anti-JCV seroconversion during treatment with natalizumab further lowers its specificity over time. Specificity of the risk factor treatment duration varies depending on the average treatment duration and the number of short-term patients. These short-term patients reduce overall average treatment duration and thus enhance the specificity of the risk factor and reduce overall PML incidence. It is also suggested that short-term natalizumab patients are exclusively non-PML, even though they might still develop PML. Clinicians have to consider the cumulative risk of patients to stratify efficiently.

Anti-JC virus seroprevalence in a Spanish multiple sclerosis cohort: JC virus seroprevalence in Spain

OBJECTIVE

To estimate the seroprevalence of anti-JCV antibodies, seroconverting rates and evolution of antibody levels in a multiple sclerosis (MS) Spanish cohort.

METHODS

Multicenter, retrospective cross-sectional and longitudinal study. The JCV seroprevalence was analyzed in 711 MS patients by using 1st (STRATIFY-1) and 2nd generation (STRATIFY-2) two-step ELISA over 2.65 (±0.97) years. Seroconversion rate was obtained over 2 samples from 314 patients, and index stability from 301 patients with 3 or more samples available. The effect of each ELISA generation, demographics, clinical characteristics and therapy on seroprevalence was assessed by logistic regression.

RESULTS

The overall anti-JCV seroprevalence was 55.3% (51.6-58.9), similar across regions (p=0.073). It increased with age (p<0.000) and when STRATIFY-2 was used (60.5%, p=0.001). Neither sex nor immunosuppressive therapy had any influence. Yearly seroconversion rate was 7% (considering only STRATIFY-2). Serological changes were observed in 24/301 patients, 5.7% initially seropositive reverted to seronegative and 7% initially seronegative changed to seropositive and again to seronegative, all these cases had initial index values around the assay's cut-off.

CONCLUSIONS

JCV seroprevalence in Spanish MS patients was similar to that reported in other European populations. Changes in serostatus are not infrequent and should be considered in clinical decisions.