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

Factors Associated With Disease-Modifying Therapy Adherence and Persistence in Multiple Sclerosis: A Scoping Literature Review

BACKGROUND

Patients with multiple sclerosis (MS) receiving disease-modifying therapies (DMT) show published adherence rates of 27.0% to 93.8% and published persistence rates of 49.7% to 96.5%. Improvements in DMT adherence and persistence are key to optimizing MS care, and enhanced understanding could improve MS disease management and identify research gaps. This scoping literature review aims to examine the nature and findings of the literature evaluating factors associated with DMT adherence and persistence in patients with MS.

METHODS

Eligible articles included in the literature review were quantitative clinical studies written in English, included adherence or persistence as primary outcomes, and accounted for covariates/confounders. The articles were assessed to identify factors associated with adherence/persistence and analyzed according to DMT type (self-injectable, oral, infusion).

RESULTS

Fifty-eight studies (103,450 patients) were included. Study distribution by DMT type was self-injectable only (n = 41), oral only (n = 2), infusion only (n = 1), and more than 1 type (n = 14). Older age and previous DMT use were associated with increased adherence and/or persistence. Increased alcohol consumption, DMT adverse events, higher education, and higher body mass index were negatively associated with adherence and/or persistence. Greater number and severity of relapses was associated with increased adherence but decreased persistence.

CONCLUSIONS

Most studies examined factors associated with adherence and persistence to self-injectable DMTs. These factors should be evaluated further for oral and infusion DMTs. Insights into the modifiable factors associated with adherence and persistence could guide treatment decisions and help improve adherence and clinical outcomes.

Longitudinal stability of JCV antibody index in Natalizumab treated people with multiple sclerosis

OBJECTIVE

The aim of this study was to evaluate the evolution of JCV index over time in Natalizumab treated people with multiple sclerosis.

MATERIALS AND METHODS

We retrospectively reviewed antibody index values from pwMS who were treated with Natalizumab for greater than six months and had at least two antibody results available between 2011 and 2019. Survival analysis was performed on those who were JCV index value negative at baseline to evaluate time to seroconversion. In pwMS who had index values available at 48 and/or 96 months post Natalizumab initiation, t-tests were performed to evaluate change in index over time.

RESULTS

1144 JCV antibody index results were available for 132 pwMS. Median time to seroconversion based on survival analysis was 103 months. Annualised seroconversion rate was 5.8%. Initial antibody index and rate of seroconversion did not differ with regards to age or gender. Antibody index increased significantly over time on treatment for the cohort as a whole, initial antibody index (0.27) to final antibody testing (0.86), t(131)=6.45, p<.0005. There was a significant increase in those with initial positive index value, between first (0.95) and final index (2.14), t(33) = 4.85, p<.0005 over a median of 77 months.

CONCLUSIONS

In those who were seronegative at baseline there is a long median duration of treatment with Natalizumab prior to seroconversion. In individuals with positive JCV antibody index at treatment initiation, antibody index increases over time.

Patient and treatment characteristics and safety outcomes of patients with relapsing-remitting multiple sclerosis treated with natalizumab in Greece: Results from the multicenter, 5-year prospective observational study 'TOPICS greece'

Background

Natalizumab is a highly efficacious treatment for relapsing-remitting multiple sclerosis (RRMS).

Objective

To assess the real-world long-term safety of natalizumab in RRMS.

Methods

This multicenter, 5-year prospective observational study, included adults with RRMS newly initiated on natalizumab as per the approved product label in the routine care in Greece. Safety was evaluated by collecting serious adverse events (SAEs) following study enrollment.

Results

Between 19-Apr-2012 and 18-Dec-2014, 304 eligible patients (median age at natalizumab initiation: 38.0 years; median disease duration: 6.2 years) were enrolled by 20 hospital-based neurologists. Over a median treatment duration period of 58.7 months, 50.7% of the patients discontinued natalizumab, mainly due to anti-JCV antibody detection (59.1%). The adverse event treatment discontinuation rate was 5.2%. The SAE incidence rate during the safety data collection period (median: 48.7 months) was 4.6%. The most common SAEs were infections (1.0%), including 2 cases (0.7%) of progressive multifocal leukoencephalopathy (PML), and no other opportunistic infections. PML diagnoses occurred 6.2-6.7 years after natalizumab initiation, and approximately 2 years after first detection of anti-JCV antibody for both patients. The incidence rate of malignancies was 0.7%.

Conclusion

In real-world settings in Greece, natalizumab displayed an acceptable safety profile, with no new safety signals emerging.

Exploring the Cost Effectiveness of Shared Decision Making for Choosing between Disease-Modifying Drugs for Relapsing-Remitting Multiple Sclerosis in the Netherlands: A State Transition Model

Background

Up to 31% of patients with relapsing-remitting multiple sclerosis (RRMS) discontinue treatment with disease-modifying drug (DMD) within the first year, and of the patients who do continue, about 40% are nonadherent. Shared decision making may decrease nonadherence and discontinuation rates, but evidence in the context of RRMS is limited. Shared decision making may, however, come at additional costs. This study aimed to explore the potential cost-effectiveness of shared decision making for RRMS in comparison with usual care, from a (limited) societal perspective over a lifetime.

Methods

An exploratory economic evaluation was conducted by adapting a previously developed state transition model that evaluates the cost-effectiveness of a range of DMDs for RRMS in comparison with the best supportive care. Three potential effects of shared decision making were explored: 1) a change in the initial DMD chosen, 2) a decrease in the patient’s discontinuation in using the DMD, and 3) an increase in adherence to the DMD. One-way and probabilistic sensitivity analyses of a scenario that combined the 3 effects were conducted.

Results

Each effect separately and the 3 effects combined resulted in higher quality-adjusted life years (QALYs) and costs due to the increased utilization of DMD. A decrease in discontinuation of DMDs influenced the incremental cost-effectiveness ratio (ICER) most. The combined scenario resulted in an ICER of €17,875 per QALY gained. The ICER was sensitive to changes in several parameters.

Conclusion

This study suggests that shared decision making for DMDs could potentially be cost-effective, especially if shared decision making would help to decrease treatment discontinuation. Our results, however, may depend on the assumed effects on treatment choice, persistence, and adherence, which are actually largely unknown.

PML risk is the main factor driving the choice of discontinuing natalizumab in a large multiple sclerosis population: results from an Italian multicenter retrospective study

BACKGROUND

Natalizumab (NTZ) is an effective treatment for relapsing-remitting multiple sclerosis (RRMS). However, patients and physicians may consider discontinuing NTZ therapy due to safety or efficacy issues. The aim of our study was to evaluate the NTZ discontinuation rate and reasons of discontinuation in a large Italian population of RRMS patients.

MATERIALS AND METHODS

The data were extracted from the Italian MS registry in May 2018 and were collected from 51,845 patients in 69 Italian multiple sclerosis centers. MS patients with at least one NTZ infusion in the period between June 1st 2012 to May 15th 2018 were included. Discontinuation rates at each time point were calculated. Reasons for NTZ discontinuation were classified as "lack of efficacy", "progressive multifocal leukoencephalopathy (PML) risk" or "other".

RESULTS

Out of 51,845, 5151 patients, 3019 (58.6%) females, with a mean age of 43.6 ± 10.1 years (median 40), were analyzed. Out of 2037 (39.5%) who discontinued NTZ, a significantly higher percentage suspended NTZ because of PML risk compared to lack of efficacy [1682 (32.7% of 5151) vs 221 (4.3%), p < 0.001]; other reasons were identified for 99 (1.9%) patients. Patients discontinuing treatment were older, had longer disease duration and worse EDSS at the time of NTZ initiation and at last follow-up on NTZ treatment. The JCV index and EDSS at baseline were predictors for stopping therapy (HR 2.94, 95% CI 1.22-4.75; p = 0.02; HR 1.36, 95% CI 1.18-5.41; p = 0.04).

CONCLUSIONS

Roughly 60% of MS patients stayed on NTZ treatment during the observation period. For those patients in whom NTZ discontinuation was required, it was mainly due to PML concerns.

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.

Current review and next steps for artificial intelligence in multiple sclerosis risk research

In the last few decades, the prevalence of multiple sclerosis (MS), a chronic inflammatory disease of the nervous system, has increased, particularly in Northern European countries, the United States, and United Kingdom. The promise of artificial intelligence (AI) and machine learning (ML) as tools to address problems in MS research has attracted increasing interest in these methods. Bayesian networks offer a clear advantage since they can integrate data and causal knowledge allowing for visualizing interactions between dependent variables and potential confounding factors. A review of AI/ML research methods applied to MS found 216 papers using terms "Multiple Sclerosis", "machine learning", "artificial intelligence", "Bayes", and "Bayesian", of which 90 were relevant and recently published. More than half of these involve the detection and segmentation of MS lesions for quantitative analysis; however clinical and lifestyle risk factor assessment and prediction have largely been ignored. Of those that address risk factors, most provide only association studies for some factors and often fail to include the potential impact of confounding factors and bias (especially where these have causal explanations) that could affect data interpretation, such as reporting quality and medical care access in various countries. To address these gaps in the literature, we propose a causal Bayesian network approach to assessing risk factors for MS, which can address deficiencies in current epidemiological methods of producing risk measurements and makes better use of observational data.

Natalizumab: safety and risk in patients with relapsing-remitting multiple sclerosis

OBJECTIVE

To estimate the risk of progressive multifocal leukoencephalopathy (PML) and the safety of natalizumab administration in patients with relapsing-remitting multiple sclerosis (RRMS).

METHODS

A descriptive retrospective observational study including all patients with RRMS treated with natalizumab followed-up after 10 years.The likelihood of developing PML was estimated based on three risk factors: anti-John Cunningham virus antibody index, previous immunosuppressive therapy, and duration of treatment. Patients were classified into five categories: minimum probability (<0.1/1000); low (0.1/1000); medium-low (0.2-0.6/1000); medium-high (0.8-3/1000); high probability (3-10/1000).

RESULTS

34 patients were included. The probability of PML in the last cycle was: 55.9% minimum, 8.8% low, 11.8% medium-low, 3% medium-high, and 20.5% high. 12 patients continue with active treatment with natalizumab. No cases of PML have been confirmed. Adverse effects were detected in 50% of patients.

CONCLUSIONS

Quantifying risk factors allows us to estimate the probability of PML appearance, thus assessing the maintenance or suspension of natalizumab.

High-Efficacy Disease-Modifying Therapies in People with Relapsing-Remitting Multiple Sclerosis: The Role of Risk Attitude in Treatment Decisions

BACKGROUND

Risk attitude is defined as the willingness to tolerate risk to achieve a greater expected return. Limited information is available on how relapsing-remitting multiple sclerosis people's perceptions about disease trajectory and risk attitude may influence treatment choices.

METHODS

A non-interventional study applying principles of behavioral economics was conducted to assess willingness to receive unwarranted high-efficacy disease-modifying therapy (DMT) according to best-practice guidelines. People with relapsing-remitting multiple sclerosis (PwRRMS) according to 2010 McDonald criteria completed a survey on symptom severity, risk preferences, and management of simulated case scenarios mimicking the current treatment landscape. PwRRMS's choice for high-efficacy agents was established as the participant's selection of monoclonal antibodies for case scenarios with at least 2 years of clinical and radiological stability.

RESULTS

A total of 211 PwRRMS were studied (mean age 39.1 ± 9.5 years, 70.1% female, mean Expanded Disability Status Scale score 1.8 ± 1.1). Almost 50% (n = 96) opted for a high-efficacy DMT despite the lack of evidence of disease activity. Younger age and risk-seeking behavior were associated with an increased likelihood of selecting unwarranted high-efficacy DMT [odds ratio (OR) 2.00, 95% confidence interval (CI) 1.02-3.93, p = 0.043, and OR 2.17, 95% CI 1.09-4.30, p = 0.027, respectively]. Clinical characteristics or subjective perception of symptom severity had no influence on participants' treatment choices.

CONCLUSION

Identifying PwRRMS with risk-seeking behavior would be crucial to implementing specific educational strategies to manage information on disease prognosis, treatment expectations, and safety risk knowledge.

High-efficacy therapies for relapsing-remitting multiple sclerosis: implications for adherence. An expert opinion from the United Arab Emirates

The number of disease-modifying treatments (DMDs) for relapsing-remitting multiple sclerosis has increased. DMDs differ not only in their efficacy and safety/tolerability, but also in the treatment burden of, associated with their initiation, route/frequency of administration, maintenance treatment and monitoring. High-efficacy DMDs bring the prospect of improved suppression of relapses and progression of disability, but may have serious safety issues, and burdensome long-term monitoring. Studies of patient preferences in this area have focused on side effects, efficacy and route of administration. Adherence to DMDs is often suboptimal in relapsing-remitting multiple sclerosis and there is a need to understand more about how the complex therapeutic and administration profiles of newer DMDs interact with these barriers to support optimal adherence to therapy.

Long-term real-world evidence for sustained clinical benefits of fingolimod following switch from natalizumab

BACKGROUND

The risk of progressive multifocal leukoencephalopathy limits the duration over which patients can receive natalizumab before requiring a switch to other therapies such as fingolimod. To date, no studies have assessed the long-term real-world effectiveness and safety of fingolimod following a switch from natalizumab. We aimed to investigate the benefit-risk profile of fingolimod over 48 months in patients switching from natalizumab, and the impact of washout duration after natalizumab discontinuation on outcomes during fingolimod treatment.

METHODS

This analysis used data from PANGAEA, an ongoing German multicenter, prospective, non-interventional, observational study. In total, 3912 patients were included: 530 had switched from natalizumab (natalizumab subpopulation), and a reference population of 3382 had switched from other treatments or were treatment-naïve (non-natalizumab subpopulation). The natalizumab subpopulation was stratified by washout duration (30-89 days, 90-149 days, and ≥ 150 days) prior to fingolimod initiation.

RESULTS

In the natalizumab subpopulation over 48 months of fingolimod treatment, 58.2% (n = 227/390) of patients remained on fingolimod. Over this period, mean annualized relapse rates (ARRs) and proportions of patients who relapsed were similar across washout durations, and ranged from 0.455 (95% confidence interval [CI]: 0.363-0.571) to 0.546 (95% CI: 0.446-0.669) and 54.1% (n = 92/170) to 60.2% (n = 127/211), respectively. Overall, 17.1% (n = 36/211) had 6-month confirmed disability worsening. In the non-natalizumab subpopulation, ARR was 0.300, 40.9% (n = 1325/3237) of patients relapsed, and a similar proportion to the natalizumab subpopulation had 6-month disability worsening (16.6% [n = 232/1394]). In both subpopulations, the safety profile of fingolimod was consistent with that observed in randomized controlled trials.

CONCLUSIONS

In patients discontinuing natalizumab, fingolimod has a favorable benefit-risk profile over 48 months. These findings also suggest using a short washout following natalizumab discontinuation, consistent with guidelines and current clinical practice in Germany.

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.

Early diagnosis of progressive multifocal leucoencephalopathy: longitudinal lesion evolution

OBJECTIVE

Early diagnosis of natalizumab-related progressive multifocal leucoencephalopathy (NTZ-PML) in multiple sclerosis has been deemed a major priority by the regulatory agencies but has yet to become a reality. The current paper aims to: (1) investigate whether patients with NTZ-PML pass through a prolonged presymptomatic phase with MRI abnormalities, (2) estimate the longitudinal PML lesion volume increase during the presymptomatic phase and (3) estimate the presymptomatic phase length and its impact on therapy duration as a risk stratification parameter.

METHODS

All Italian patients who developed NTZ-PML between 2009 and 2018 were included. The data of patients with available prediagnostic MRI were analysed (n=41). Detailed clinical and neuroradiological information was available for each participant.

RESULTS

(1) PML lesions were detectable in the presymptomatic phase in 32/41 (78%) patients; (ii) the lesion volume increased by 62.8 % for each month spent in the prediagnostic phase; (3) the prediagnostic phase length was 150.8±74.9 days; (4) PML MRI features were detectable before the 24th month of therapy in 31.7 % of patients in our cohort.

CONCLUSIONS

Considering the latency of PML clinical manifestation, the presymptomatic phase length supports the usefulness of MRI surveillance every 3-4  months. Early diagnosis could prompt a better outcome for patients due to the relationship between lesion volume and JC virus infection. The insight from this study might also have an impact on risk stratification algorithms, as therapy duration as a parameter of stratification appears to need reassessment.

Progressive multifocal leukoencephalopathy in Finland: a cross-sectional registry study

Objective

To investigate if progressive multifocal leucoencephalopathy (PML) incidence has increased in Finland like in the neighbouring Sweden.

Methods

National administrative registries were searched for all PML admissions aged 16 years or more in 2004–2014 on all neurological and internal medicine wards in Finland. The mortality data of the patients was extracted from the national causes of death registry. National level data on annual predisposing drug use was obtained from the national pharmaceutical authority.

Results

We identified 35 PML cases (57% male) with a peak in 2010–2011 that amounted to 49% of all cases. The annual incidence for the entire study period was 0.072/100,000 person-years (95% CI 0.050–0.10) with no temporal trend (p = 0.18). Mean age was 57 years (22–88 years) with no sex difference (p = 0.42). Neoplasms (60%), HIV infection (17%) and systemic connective tissue disorders (CTD, 14%) were the most common predisposing conditions. MS was recorded in three cases (9%). The national level use of drugs that predispose to PML increased during the study period, with the exceptions of alemtuzumab and fludarabine. Overall survival was 85% at 90 days, 79% at 1 year, and 66% at 5 years. Survival was worst in patients with malignancy and best in patients with CTD.

Conclusions

PML most often occurs in patients with malignancies and patients with HIV or CTD cover a third. PML incidence in Finland is lower than in Sweden and shows no temporal trend despite increasing use of predisposing drugs. Mortality after PML varies according to the predisposing condition.

Electronic supplementary material

The online version of this article (10.1007/s00415-018-09167-y) contains supplementary material, which is available to authorized users.

Age as a risk factor for early onset of natalizumab-related progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy (PML) is a rare but potentially fatal opportunistic infection that arises almost exclusively in immunocompromised patients or in those treated with monoclonal antibodies, especially natalizumab. Here, we aimed at exploring if age at treatment start affects the time to onset of natalizumab-related PML. PubMed was searched for the terms "natalizumab and progressive multifocal leukoencephalopathy" in articles published from January 2005 to March 2017. We collected information on each identified PML case, including demographic and clinical variables at natalizumab start and at PML onset. The number of natalizumab infusions until PML onset was investigated in time-to-event analyses. We identified 238 cases who developed PML after a median number of 33 natalizumab infusions (range 6 to 103). Risk factors for an earlier onset of natalizumab-related PML were prior immunosuppressant exposure (hazard ratio [HR] = 1.43, p = 0.017) and older age at treatment start (HR = 1.02, p = 0.016). In particular, patients older than 50 years had a more than doubled-increased risk for an earlier PML onset (HR = 2.11, p = 0.006). Our findings suggest that the age at natalizumab start may represent a risk factor for an earlier PML onset, thus claiming further investigations about the interplay between immunosenescence and MS treatments.