anti-JCV Antibody Index Research Articles

CD4/CD8 ratio during natalizumab treatment in multiple sclerosis patients

Although improved, the risk of progressive multifocal leukoencephalopathy is a constant threat for patient affected by multiple sclerosis treated with natalizumab.We performed a 24months longitudinal study aimed to evaluate the total WBC and lymphocytes subsets modifications and their correlations with anti-JCV antibody index after 1 and 2years of natalizumab treatment.Natalizumab induced an increase of WBC, total and C19+ lymphocytes together with a decrease of CD3+, CD4+ T lymphocytes and CD4/CD8 ratio, which was positively related to anti-JCV antibodies index at month 0, 12 and 24.Our study confirms that lymphocytes subsets are modified under NAT therapy. Implications of lymphocyte subsets alterations in the pathogenesis of PML are under analyses.

Is the risk of progressive multifocal leukoencephalopathy the real reason for natalizumab discontinuation in patients with multiple sclerosis?

BackgroundProgressive multifocal leukoencephalopathy (PML) is one of the major risks of natalizumab therapy. Despite introduction of the currently employed PML risk stratification algorithm, the incidence of natalizumab-associated PML cases is not decreasing.ObjectivesWe addressed the following questions: How do natalizumab-treated multiple sclerosis patients and their treating physicians assess and deal with PML risk? Is PML risk the real reason for natalizumab discontinuation?Methods699 natalizumab-treated multiple sclerosis patients and 99 physicians were included in this prospective observational study. Questionnaires were completed at 5 different time points. Patients were stratified into 5 subgroups according to the presence of PML risk factors (prior immunosuppression, anti-JCV antibody status, treatment duration). Patients with prior immunosuppression (n = 30, treated by n = 7 physicians) were excluded from analyses, because patient numbers were too small. Patients’ anti-JCV antibody index was not considered because data recruitment ended in 2014. Using Bayesian network and regression analysis, we examined the relationship between different patient- and physician-related factors and patients’ discontinuation of natalizumab.ResultsPatients of all subgroups and physicians assessed the PML risk as low. Overall patient adherence to natalizumab was high (87%). Only 13% of patients discontinued therapy. Natalizumab treatment cessation was associated with different patient- and physician-related factors (physicians’ assessment of general PML risk, number of treated patients per year, natalizumab treatment duration, relapses during the course of study) upon which only physicians’ judgment on treatment continuation, patients’ perception of personal PML risk, and JCV seroconversion showed significant relationships.ConclusionAccording to the currently employed risk stratification algorithm, the objective PML risk probably doesn’t play a dominant role in a patients’ decision to continue or stop natalizumab treatment. The decision-making process is rather guided by subjective views and experiences of patients and treating neurologists. Treating physicians should consider this discrepancy in their advice to improve the risk-benefit-ratio for the individual patient.

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

BackgroundRisk of natalizumab-related progressive multifocal leukoencephalopathy is associated with the presence of anti-JC-virus (JCV) antibodies.ObjectiveTo 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.MethodsMS 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.Results154 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%).ConclusionsAnti-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.

Progressive multifocal leukoencephalopathy and rheumatoid arthritis treatments

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system due to reactivation of the JC virus (JCV). PML is extremely uncommon despite the high prevalence of the virus in the general population. No specific treatment is available, and the prognosis is bleak. The diagnosis is based on brain imaging findings, detection of the JCV genome in cerebrospinal fluid samples and, in some cases, histological studies of the brain lesions. The pathophysiological mechanisms that drive the development of PML are incompletely understood. However, a consistent feature is the presence of a predisposing factor, most notably immunosuppression. The risk of developing PML varies with the underlying disease (e.g., HIV infection or autoimmune disease) and with the drugs used to treat them. Biologics have been ranked according to the risk of PML during their use. Natalizumab, a monoclonal antibody given to treat multiple sclerosis, is among the drugs associated with a high risk of PML. Patients given natalizumab are now closely monitored based on anti-JCV antibody titers and index values. In rheumatology, the expanding use of biologics has led to an increase in cases of PML, with rituximab being associated with the highest risk. Given the absence of specific recommendations, exhaustive registries and postmarketing observational studies are urgently needed to gauge the risk of PML according to the underlying disease and drug treatments, with the goal of defining optimal monitoring protocols.

Study of the anti-JCV antibody levels in a Spanish multiple sclerosis cohort.

One of the risk factor to develop progressive multifocal leukoencephalopathy (PML) among natalizumab-treated patients is the presence and high levels of anti-JCV antibodies. Our purpose was to test the association of different clinical and demographic variables with the presence and levels of anti-JCV antibodies in a Spanish cohort of patients with multiple sclerosis (MS) during natalizumab treatment. All patients with MS from two hospitals with at least one measure of the anti-JCV antibodies levels (2011-2014) were recruited, among them were two PML cases. Anti-JCV antibody levels were assessed using two-step ELISA. A total of 1061 patients (16·3% natalizumab-treated) participated in this study. The seropositivity rate of anti-JCV antibodies was 58·2%. It increased with age (Pcorrected = 0·00005) and was lower among HLA-DRB1*15:01 carriers (Pcorrected = 0·049). The two patients with PML were HLA-DRB1*15:01 carriers. We had at least three quarterly anti-JCV antibody measurements (index value) from 137 patients, whose levels did not increase during natalizumab treatment. However, 5·8% of these patients had an increase of the index value higher of one point in a maximum of 6 months, something that was more frequently observed (P = 0·054) among patients treated with immunosuppressant prior to natalizumab onset. Old age and HLA-DRB1*15:01 were the factors that influence positively and negatively, respectively, our anti-JCV antibody prevalence, although our both PML cases were HLA-DRB1*15:01carriers. Most of our patients showed a stable anti-JCV antibody index values during natalizumab treatment.

Real World Experience With Natalizumab at a Tertiary Care Pediatric IBD Center.

Natalizumab is a humanized monoclonal antibody inhibiting lymphocyte migration and prescribed in patients with Crohn disease (CD) failing anti-tumor necrosis factor (TNF) therapies. Because of the risk of progressive multifocal leukoencephalopathy in patients with John Cunningham virus (JCV) positive, natalizumab is not widely used in clinical practice. Published experience of the use of natalizumab in pediatric patients is lacking. We aimed to describe the experience of natalizumab in patients with CD, including those who are JCV positive, at a tertiary care pediatric inflammatory bowel disease center. A retrospective chart review was performed in patients with CD <21 years receiving natalizumab therapy before March 2014. Patient and disease information, prior treatments and response to natalizumab, including Harvey Bradshaw Index (HBI), were recorded. Descriptive statistics were computed. Nine patients received natalizumab with a median age at diagnosis of 10 (range 7-16) years and median disease duration 72 (range 13-156) months. All of the patients had failed at least 1 anti-TNF agent. At baseline, the median HBI was 8 (IQR 6.5-11). By week 10, the median HBI was 4.5 (IQR 2-6), with 4 of 8 (50%) patients with CD being in remission. Forty-four percent (4/9) of patients were JCV antibody positive at baseline and had anti-JCV antibody index >0.9 (median 3.36). There were no serious adverse events, including progressive multifocal leukoencephalopathy. All of the patients were transitioned to vedolizumab. In our experience, natalizumab is a safe and efficacious medication in pediatric in patients with inflammatory bowel disease. Given the favorable results with natalizumab, pediatric studies with the more gut targeted anti-integrin agent vedolizumab are warranted.

Longitudinal Analysis of Anti-JCV Antibody Index in Natalizumab-Treated Multiple Sclerosis Patients (P6.182)

Longitudinal Analysis of Anti-JCV Antibody Index in Natalizumab-Treated Multiple Sclerosis Patients (P6.182)

High cumulative JC virus seroconversion rate during long-term use of natalizumab.

John Cunningham virus (JCV) seropositivity is a risk factor for the development of natalizumab-associated progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS) patients. When JCV seronegative patients seroconvert, their risk of developing PML increases. Limited longitudinal data exist about the seroconversion rate amongst natalizumab-treated relapsing-remitting MS (RRMS) patients. Our objective was to evaluate the seroconversion rate in a large Dutch cohort of natalizumab-treated RRMS patients. Seroconversion was defined as at least two consecutive seropositive serum samples (or cessation of therapy after a single seropositive sample because of seropositivity) after initial seronegative testing. In our study of 179 patients for whom longitudinal blood samples were available over a long period (median 4.2 years), anti-JCV antibody indices were measured in 933 available samples. Eighty-six patients (48.0%) tested seronegative initially. Of these 86 seronegative patients, 23 patients (26.7%) seroconverted during follow-up. The annualized seroconversion rate was 7.1%. Seroconversion occurred between 9 and 90 months (median 43 months) of treatment. The rate of seroconversion was independent of follow-up duration. No significant increase was seen in the anti-JCV antibody index in the non-converting patients during the follow-up. The annualized seroconversion rate of 7.1% in patients using natalizumab, cumulatively leading to more than 25% of seronegative patients becoming seropositive in 4 years, is of clinical relevance and should be taken into account in the risk assessment when considering the start of natalizumab therapy.

Longitudinal analyses of anti-JCV antibody index for risk assessment of progressive multifocal leukoencephalopathy.

Risk assessment for natalizumab-associated progressive multifocal leukoencephalopathy (Nat-PML) comprises the anti-JC virus (JCV) antibody index (AI). The anti-JCV AI was longitudinally determined in a natalizumab-treated MS cohort (Nat-MS, n = 468) and samples of Nat-PML patients (n = 15). In Nat-MS, the median AI was 0.8 (25th to 75th percentile, 0.2–2.8) with an intra-individual coefficient of variation (CV) of 9.8% (4.8–17.6). Patients with an AI ≤ 0.9 exhibited higher CV. The AI was higher (3.4 (3.1–3.6)) in samples before Nat-PML diagnosis than in seropositive Nat-MS (2.4 (1.0–3.4), n = 298, p = 0.010). AIs ≥ 3.0 were associated with a 14.5-fold (95% CI 2.3–90.4) increased PML risk (p = 0.002). Groups with an AI below 1.5 exhibit higher variability or even serostatus fluctuation. AI dynamics require further investigation.

PML risk stratification using anti-JCV antibody index and L-selectin

Background: Natalizumab treatment is associated with progressive multifocal leukoencephalopathy (PML) development. Treatment duration, prior immunosuppressant use, and JCV serostatus are currently used for risk stratification, but PML incidence stays high. Anti-JCV antibody index and L-selectin (CD62L) have been proposed as additional risk stratification parameters. Objective: This study aimed at verifying and integrating both parameters into one algorithm for risk stratification. Methods: Multicentric, international cohorts of natalizumab-treated MS patients were assessed for JCV index (1921 control patients and nine pre-PML patients) and CD62L (1410 control patients and 17 pre-PML patients). Results: CD62L values correlate with JCV serostatus, as well as JCV index values. Low CD62L in natalizumab-treated patients was confirmed and validated as a biomarker for PML risk with the risk factor “CD62L low” increasing a patient’s relative risk 55-fold (p < 0.0001). Validation efforts established 86% sensitivity/91% specificity for CD62L and 100% sensitivity/59% specificity for JCV index as predictors of PML. Using both parameters identified 1.9% of natalizumab-treated patients in the reference center as the risk group. Conclusions: Both JCV index and CD62L have merit for risk stratification and share a potential biological relationship with implications for general PML etiology. A risk algorithm incorporating both biomarkers could strongly reduce PML incidence.

Association between soluble L-selectin and anti-JCV antibodies in natalizumab-treated relapsing-remitting MS patients

ObjectiveIn relapsing-remitting MS (RRMS) patients treated with natalizumab, the low level of L-selectin-expressing CD4+ T cells has been associated with the risk of progressive multifocal leukoencephalopathy (PML). In this study, our aim was to correlate the levels of soluble L-selectin and the anti-JCV antibody index in the sera of RRMS patients treated with natalizumab. MethodsThis study included 99 subjects, including 44 RRMS patients treated with natalizumab, 30 with interferon beta (IFN-β) and 25 healthy controls. The levels of soluble l-selectin (sL-selectin) in sera were measured by ELISA, and the anti-JC Virus (JCV) antibody index was determined by the second–generation ELISA (STRATIFY JCVTM DxSelectTM) assay. ResultsA significant correlation was found between the levels of sL-selectin and anti-JCV antibody indices in sera in the natalizumab-treated patients (r=0.402; p=0.007; n=44), but not in those treated with IFN-β. This correlation became even stronger in JCV seropositive patients treated with natalizumab for longer than 18 months (r=0.529; p=0.043; n=15). ConclusionThe results support the hypothesis of sL-selectin being connected to the anti-JCV antibody index values and possibly cellular L-selectin. Measurement of serum sL-selectin should be evaluated further as a potential biomarker for predicting the risk of developing PML.

Longitudinal JCV serology in multiple sclerosis patients preceding natalizumab-associated progressive multifocal leukoencephalopathy

The presence of anti-John Cunningham Virus (JCV) antibodies is a risk factor for the development of progressive multifocal leukoencephalopathy (PML) in MS patients treated with natalizumab. It has been suggested that an increase in serum anti-JCV antibody index precedes the development of PML. We here describe extensive longitudinal serum anti-JCV antibody indexes of four MS patients who developed PML. Anti-JCV antibodies were measured using the STRATIFY JCV™DxSelect™ test. All four patients had rather stable high anti-JCV antibody indexes in all samples obtained before developing PML. Possibly caused by reaching the saturation level of the assay, no increase in anti-JCV antibody indexes was seen just before the diagnosis of PML. This study confirms that high serum anti-JCV antibody indexes precede natalizumab-associated PML.

Anti–JC virus antibody levels in serum or plasma further define risk of natalizumab‐associated progressive multifocal leukoencephalopathy

ObjectiveThe increased risk of progressive multifocal leukoencephalopathy (PML) with natalizumab treatment is associated with the presence of anti–JC virus (JCV) antibodies. We analyzed whether anti-JCV antibody levels, measured as index, may further define PML risk in seropositive patients.MethodsThe association between serum or plasma anti-JCV antibody levels and PML risk was examined in anti-JCV antibody–positive multiple sclerosis (MS) patients from natalizumab clinical studies and postmarketing sources. For PML and non-PML patients, the probabilities of having an index below and above a range of anti-JCV antibody index thresholds were calculated using all available data and applied to the PML risk stratification algorithm. Longitudinal stability of anti-JCV antibody index was also evaluated.ResultsAnti-JCV antibody index data were available for serum/plasma samples collected >6 months prior to PML diagnosis from 71 natalizumab-treated PML patients and 2,522 non-PML anti-JCV antibody–positive patients. In patients with no prior immunosuppressant use, anti-JCV antibody index distribution was significantly higher in PML patients than in non-PML patients (p < 0.0001). Among patients who were anti-JCV antibody negative at baseline in the AFFIRM and STRATIFY-1 trials, 97% remained consistently negative or below an index threshold of 1.5 over 18 months. Retrospective analyses of pre-PML samples collected longitudinally from PML patients displayed sustained higher anti-JCV antibody index over time.InterpretationAnti-JCV antibody levels in serum/plasma, measured as index, may differentiate PML risk in anti-JCV antibody–positive MS patients with no prior immunosuppressant use. Continued evaluation of anti-JCV antibody index and PML risk is warranted. Ann Neurol 2014;76:802–812