Exposure to natalizumab throughout pregnancy: effectiveness and safety in an Italian cohort of women with multiple sclerosis.

OBJECTIVE: Assessing the risk of clinical and radiological reactivation during pregnancy and post partum in women with multiple sclerosis (MS) treated with natalizumab (NTZ) throughout pregnancy (LONG_EXP) compared with women interrupting treatment before (NO_EXP) and within >-30 days and ≤90 days from conception (SHORT_EXP), and describing newborns' outcomes. METHODS: Maternal clinical and radiological outcomes and obstetric and fetal outcomes were retrospectively collected and compared among groups (NO_EXP, SHORT_EXP, LONG_EXP). Predictors of clinical and radiological reactivation were investigated through univariable and multivariable analysis. RESULTS: 170 eligible pregnancies from 163 women referring to 29 Italian MS centres were included. Annualised relapse rate (ARR) was significantly lower in LONG_EXP (n=66, 0.02 (0.001-0.09)) compared with NO_EXP (n=31, 0.43 (0.21-0.75), p=0.002) and SHORT_EXP (n=73, 0.46 (0.30-0.66), p=0.0004) during pregnancy, and in LONG_EXP (0.12 (0.05-0.24)) compared with SHORT_EXP (0.30 (0.17-0.50), p=0.008) during post partum. Gadolinium-enhancing (Gd+) lesions were less frequent in LONG_EXP (n=6/50, 2.00%) compared with NO_EXP (n=9/21, 42.86%) and SHORT_EXP after delivery (n=17/49, 34.69%, p=0.010).Delaying NTZ resumption after delivery significantly increased the risk of relapses (OR=1.29 (95% CI 1.07 to 1.57), p=0.009) and Gd+ lesions (OR=1.49 (95% CI 1.17 to 1.89, p=0.001). Newborns' weight, length, head circumference and gestational age did not differ among groups after adjusting for confounders. Anaemia was tracked in 4/69 LONG_EXP newborns. Congenital anomaly rate was within the expected range for the untreated MS population. CONCLUSIONS: Our findings indicate that in women with MS treated with NTZ before conception, continuation of NTZ throughout pregnancy and its early resumption after delivery mitigate the risk of clinical and radiological reactivation. This approach has no major impact on newborns' outcomes.

Anti-SARS-CoV-2 T-stem cell memory persists in ocrelizumab-treated MS patients.

BACKGROUND: Development of long-lasting anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) T-cell responses in persons with multiple sclerosis (pwMS) treated with ocrelizumab is questioned. OBJECTIVE: Investigate antiviral T-cell responses after infection with SARS-CoV-2 in ocrelizumab-treated pwMS. Control groups included ocrelizumab-treated pwMS without SARS-CoV-2 infection, and non-MS individuals with and without SARS-CoV-2 infection. METHODS: Peripheral blood mononuclear cells were stimulated with SARS-CoV-2 peptide pools and T-cell reactivity was assessed by ELISPOT for interferon (IFN)-γ detection, and by multiparametric fluorescence-activated cell sorting (FACS) analyses for assessment and characterization of T-cell activation. RESULTS: ELISPOT assay against the spike and the N protein of SARS-CoV-2 displayed specific T-cell reactivity in 28/29 (96%) pwMS treated with ocrelizumab and infected by SARS-CoV-2, similar to infected persons without MS. This reactivity was present 1 year after infection and independent from the time of ocrelizumab infusion. FACS analysis following stimulation with SARS-CoV-2 peptide pools showed the presence of activation-induced markers (AIMs) in both CD4+ and CD8+ T-cell subsets in 96% and 92% of these individuals, respectively. Within naïve AIM+ CD4+ and CD8+ T-cells, we detected T memory stem cells, suggesting the acquisition of long-term memory. CONCLUSIONS: B-cell depletion using ocrelizumab does not impair the development of long-lasting anti-SARS-CoV-2 T-cell responses.

Multiple Sclerosis Progressive Courses: A Clinical Cohort Long-Term Disability Progression Study.

OBJECTIVES: Improving the understanding of multiple sclerosis (MS) mechanism and disability progression over time is essential to assess the value of healthcare interventions. Poor or no data on disability progression are available for progressive courses. This study aims to fill this gap. METHODS: An observational cohort study of patients with primary MS (PPMS) and secondary progressive MS (SPMS) was conducted on 2 Italian MS centers disease registries over an observational time of 34 years. Annual transition probabilities among Expanded Disability Status Scale (EDSS) states were estimated using continuous Markov models. A sensitivity analysis was performed in relation to clinical characteristic associated to disability progression. RESULTS: The study cohort included 758 patients (274 PPMS and 434 SPMS) with a median follow-up of 8.2 years. Annual transition probability matrices of SPMS and PPMS reported different annual probabilities to move within EDSS levels. Excluding EDSS associated to relapse events or patient with relapses, the annual probability of staying stable in an EDSS level increased in both disease courses even not significantly. CONCLUSIONS: This study provides estimates of annual disability progression as EDSS changes for PPMS and SPMS. These estimates could be a useful tool for healthcare decision makers and clinicians to properly assess impact of clinical interventions.

Changes in Brain Volumes Are Relevant during Natalizumab-Associated Progressive Multifocal Leukoencephalopathy: Lessons from a Case Report.

This is a case report concerning a Natalizumab-associated Progressive Multifocal Leukoencephalopathy (PML) with cerebellar localization and wakefulness disturbances. Awakening and clinical improvement dramatically occurred as soon as the immune reconstitution inflammatory syndrome (IRIS) took place, being it mild in nature and colocalizing with the PML lesion. In these ideal experimental conditions, we applied brain magnetic resonance imaging post-analysis in order to know changes in brain volumes underlying the pathological process over the infection period. White matter volume increased with a decrease in grey matter during IRIS. Conversely, we found a constant increase in cerebrospinal fluid volume throughout the duration of PML, suggesting a widespread abiotrophic effect, far from the lesion. Furthermore, brain parenchymal fraction significantly decreased as expected while the total brain volume remained stable at all times. Neurodegeneration is the main contributor to the steady disability in Natalizumab-associated PML. This process is thought to be widespread and inflammatory in nature as well as sustained by IRIS and humoral factors derived from the PML lesion.

The CSF Profile Linked to Cortical Damage Predicts Multiple Sclerosis Activity.

OBJECTIVE: Intrathecal inflammation correlates with the grey matter damage since the early stages of multiple sclerosis (MS), but whether the cerebrospinal fluid (CSF) profile can help to identify patients at risk of disease activity is still unclear. METHODS: We evaluated the association between CSF levels of 18 cytokines, previously found to be associated to grey matter damage, and the disease activity, among 99 patients with relapsing-remitting MS, who underwent blinded clinical and 3 T magnetic resonance imaging (MRI) evaluations for 4 years. Groups with evidence of disease activity (EDA) or no evidence of disease activity (NEDA; occurrence of relapses, new white matter lesions, and Expanded Disability Status Scale [EDSS] change) were identified. Cortical lesions and the annualized cortical thinning were also evaluated. RESULTS: Forty-one patients experienced EDA and, compared to the NEDA group, had at diagnosis higher CSF levels of CXCL13, CXCL12, IFNγ, TNF, sCD163, LIGHT, and APRIL (p < 0.001). In the multivariate analysis, CXCL13 (hazard ratio [HR] = 1.35; p = 0.0002), LIGHT (HR = 1.22; p = 0.005) and APRIL (HR = 1.78; p = 0.0001) were the CSF molecules more strongly associated with the risk of EDA. The model, including CSF variables, predicted more accurately the occurrence of disease activity than the model with only clinical/MRI parameters (C-index at 4 years = 71% vs 44%). Finally, higher CSF levels of CXCL13 (ß = 4.7*10-4 ; p < 0.001), TNF (ß = 3.1*10-3 ; p = 0.004), LIGHT (ß = 2.6*10-4 ; p = 0.003), sCD163 (ß = 4.3*10-3 ; p = 0.009), and TWEAK (ß = 3.4*10-3 ; p = 0.024) were associated with more severe cortical thinning. INTERPRETATION: A specific CSF profile, mainly characterized by elevated levels of B-cell related cytokines, distinguishes patients at high risk of disease activity and severe cortical damage. The CSF analysis may allow stratifications of patients at diagnosis for optimizing therapeutic approaches. ANN NEUROL 2020;88:562-573.

Switching to ocrelizumab in RRMS patients at risk of PML previously treated with extended interval dosing of natalizumab.

Discontinuation of natalizumab in patients with relapsing-remitting multiple sclerosis (RRMS) at risk of progressive multifocal leukoencephalopathy (PML) is associated with disease reactivation. Forty-two RRMS patients, who switched from an extended interval dose (EID) of natalizumab to ocrelizumab, underwent magnetic resonance imaging (MRI) and clinical monitoring during washout and after ocrelizumab starting. During the first 3 months, disease reactivation was observed in five (12%) patients; 6 months after ocrelizumab starting, no further relapses were recorded, and Expanded Disability Status Scale (EDSS) remained stable in 38 (90%) patients. In conclusion, ocrelizumab could be considered a choice to mitigate the risk of disease reactivation in patients previously treated with natalizumab-EID.

The risk of infection in patients with multiple sclerosis treated with disease-modifying therapies: A Delphi consensus statement.

The risk of infection associated with immunomodulatory or immunosuppressive disease-modifying drugs (DMDs) in patients with multiple sclerosis (MS) has been increasingly addressed in recent scientific literature. A modified Delphi consensus process was conducted to develop clinically relevant, evidence-based recommendations to assist physicians with decision-making in relation to the risks of a wide range of infections associated with different DMDs in patients with MS. The current consensus statements, developed by a panel of experts (neurologists, infectious disease specialists, a gynaecologist and a neuroradiologist), address the risk of iatrogenic infections (opportunistic infections, including herpes and cryptococcal infections, candidiasis and listeria; progressive multifocal leukoencephalopathy; human papillomavirus and urinary tract infections; respiratory tract infections and tuberculosis; hepatitis and gastrointestinal infections) in patients with MS treated with different DMDs, as well as prevention strategies and surveillance strategies for the early identification of infections. In the discussion, more recent data emerged in the literature were taken into consideration. Recommended risk reduction and management strategies for infections include screening at diagnosis and before starting a new DMD, prophylaxis where appropriate, monitoring and early diagnosis.

Vaccinations in patients with multiple sclerosis: A Delphi consensus statement.

BACKGROUND: Patients with multiple sclerosis (MS) are at increased risk of infection. Vaccination can mitigate these risks but only if safe and effective in MS patients, including those taking disease-modifying drugs. METHODS: A modified Delphi consensus process (October 2017-June 2018) was used to develop clinically relevant recommendations for making decisions about vaccinations in patients with MS. A series of statements and recommendations regarding the efficacy, safety and timing of vaccine administration in patients with MS were generated in April 2018 by a panel of experts based on a review of the published literature performed in October 2017. RESULTS: Recommendations include the need for an 'infectious diseases card' of each patient's infectious and immunisation history at diagnosis in order to exclude and eventually treat latent infections. We suggest the implementation of the locally recommended vaccinations, if possible at MS diagnosis, otherwise with vaccination timing tailored to the planned/current MS treatment, and yearly administration of the seasonal influenza vaccine regardless of the treatment received. CONCLUSION: Patients with MS should be vaccinated with careful consideration of risks and benefits. However, there is an urgent need for more research into vaccinations in patients with MS to guide evidence-based decision making.

Scoring the 10-year risk of ambulatory disability in multiple sclerosis: the RoAD score.

BACKGROUND AND PURPOSE: Both baseline prognostic factors and short-term predictors of treatment response can influence the long-term risk of disability accumulation in patients with relapsing-remitting multiple sclerosis (RRMS). The objective was to develop and validate a scoring system combining baseline prognostic factors and 1-year variables of treatment response into a single numeric score predicting the long-term risk of disability. METHODS: We analysed two independent datasets of patients with RRMS who started interferon beta or glatiramer acetate, had an Expanded Disability Status Scale (EDSS) score <4.0 at treatment start and were followed for at least 10 years. The first dataset ('training set') included patients attending three MS centres in Italy and served as a framework to create the so-called RoAD score (Risk of Ambulatory Disability). The second ('validation set') included a cohort of patients followed in Barcelona, Spain, to explore the performance of the RoAD score in predicting the risk of reaching an EDSS score ≥6.0. RESULTS: The RoAD score (ranging from 0 to 8) derived from the training set (n = 1225), was based on demographic (age), clinical baseline prognostic factors (disease duration, EDSS) and 1-year predictors of treatment response (number of relapses, presence of gadolinium enhancement and new T2 lesions). The best cut-off score for discriminating patients at higher risk of reaching the disability milestone was ≥4. When applied to the validation set (n = 296), patients with a RoAD score ≥4 had an approximately 4-fold increased risk for reaching the disability milestone (p < 0.001). DISCUSSION: The RoAD score is proposed as an useful tool to predict individual prognosis and optimize treatment strategy of patients with RRMS.

Natalizumab is associated with early improvement of working ability in relapsing-remitting multiple sclerosis patients: WANT observational study results.

BACKGROUND: The Work Ability in Natalizumab-Treated MS Patients (WANT) study assessed work ability, quality of life, and cognitive processing speed during natalizumab treatment. METHODS: WANT was a 1-year, prospective, multicenter observational study conducted in Italy. Inclusion criteria included relapsing-remitting multiple sclerosis (MS), natalizumab treatment, full-time worker status, and loss of working hours due to MS as measured by the Work Productivity and Activity Impairment Questionnaire for MS (WPAI:MS). The primary endpoint was change in WPAI:MS domain scores after 1 year on natalizumab. Secondary endpoints included change in annualized relapse rate (ARR), Multiple Sclerosis Impact Scale (MSIS-29) score, and Symbol Digit Modalities Test (SDMT) score. RESULTS: At enrollment, the 91 patients had a mean age of 38.3 (standard deviation [SD], 9.0) years and a mean ARR of 1.5 (SD, 0.8). After 1 year, improvements were observed in all WPAI:MS domains, with significant reductions in Absenteeism (-4.2 [SD, 26.0], p = 0.0190) and Work Productivity Loss (-7.2 [SD, 28.6]; p = 0.0456). These changes were accompanied by a low ARR (0.1), and 87.9% of patients were relapse free. Significant improvement was observed in MSIS-29 physical and psychological domains (reductions of 2.8 [SD, 11.6; p = 0.0295] and 6.3 [SD, 15.6; p = 0.0007], respectively) and SDMT score (increase of 2.4 [SD, 7.9; p = 0.0006]). Adverse events were reported in 32 of 104 patients (30.8%). CONCLUSIONS: The reductions in Absenteeism and Work Productivity Loss and the improved physical and psychological functioning reported after 1 year of natalizumab treatment in real-world settings extend our understanding of natalizumab's effects on patient-centric and health economics outcomes.

Simultaneous quantification of natural and inducible regulatory T-cell subsets during interferon-ß therapy of multiple sclerosis patients.

BACKGROUND: The mechanisms underlying the therapeutic activity of interferon-ß in multiple sclerosis are still not completely understood. In the present study, we evaluated the short and long-term effects of interferon-ß treatment on different subsets of regulatory T cells in relapsing-remitting multiple sclerosis patients biologically responsive to treatment because of mixovirus resistance protein A inducibility. METHODS: In this prospective longitudinal study, subsets of natural regulatory T cells (naïve, central memory and effector memory) and inducible regulatory T cells (Tr1), as well as in vitro-induced regulatory T cells (Tr1-like cells), were simultaneously quantified by flow cytometry in samples prepared from 148 therapy-naïve multiple sclerosis patients obtained before and after 6, 12, 18, and 24 months of interferon-ß-1a treatment. mRNA for interleukin-10 and Tr1-related genes (CD18, CD49b, and CD46, together with Cyt-1 and Cyt-2 CD46-associated isoforms) were quantified in Tr1-like cells. RESULTS: Despite profound inter-individual variations in the modulation of all regulatory T-cell subsets, the percentage of natural regulatory T cells increased after 6, 12, and 24 months of interferon-ß treatment. This increase was characterized by the expansion of central and effector memory regulatory T-cell subsets. The percentage of Tr1 significantly enhanced at 12 months of therapy and continued to be high at the subsequent evaluation points. Patients experiencing relapses displayed a higher percentage of naïve regulatory T cells and a lower percentage of central memory regulatory T cells and of Tr1 before starting interferon-ß therapy. In addition, an increase over time of central memory and of Tr1 was observed only in patients with stable disease. However, in vitro-induced Tr1-like cells, prepared from patients treated for 24 months, produced less amount of interleukin-10 mRNA compared with pre-treatment Tr1-like cells. CONCLUSION: Interferon-ß induces the expansion of T regulatory subsets endowed with a high suppressive activity, especially in clinically stable patients. The overall concurrent modulation of natural and inducible regulatory T-cell subsets might explain the therapeutic effects of interferon-ß in multiple sclerosis patients.

Early reduction of the splicing factor2/alternative splicing factor: a cellular inhibitor of the JC polyomavirus in natalizumab-treated MS patients long before developing progressive multifocal leukoencephalopathy.

Natalizumab is effective against relapsing-remitting multiple sclerosis (MS) but increases the risk of progressive multifocal leukoencephalopathy (PML), which is caused by the activation of the JCV polyomavirus. SF2/ASF (splicing factor2/alternative splicing factor) is a potent cellular inhibitor of JCV replication and large T-antigen (T-Ag) expression. We reported that SF2/ASF levels in blood cells increase during the first year of natalizumab therapy and decrease thereafter, inversely related to T-Ag expression, and suggested a correlation with JCV reactivation. Here, we report SF2/ASF levels of longitudinal blood samples of two patients undergoing natalizumab therapy, who developed PML while monitored, in comparison to natalizumab-treated controls and to one-off PML samples. After 6 months of therapy, SF2/ASF levels of the two cases were reduced, instead of increased, and their overall SF2/ASF levels were lower than those from natalizumab controls. Since SF2/ASF inhibits JCV, its early reduction might have a role in subsequent PML. We are aware of the limitations of the study, but the uniqueness of serial blood samples collected before and after PML onset in natalizumab-treated patients must be stressed. If confirmed in other patients, SF2/ASF evaluation could be a new and early biomarker of natalizumab-associated PML risk, allowing an 18-24-month interval before PML onset (presently ~ 5 months), in which clinicians could evaluate other risk factors and change therapy.

Should frequent MRI monitoring be performed in natalizumab-treated MS patients? A contribution to a recent debate.

BACKGROUND: Brain magnetic resonance imaging (MRI) is the most effective surveillance tool for the detection of asymptomatic progressive multifocal leukoencephalopathy (PML). However, the optimal frequency for routine MRI surveillance is under-investigated. OBJECTIVE: To understand whether, upon their first MRI appearance, PML lesions present a difference in volume when comparing patients who frequently underwent MRI surveillance (3/4 months) with those who were assessed at longer intervals (6/12 months) and to understand the impact of the volume of lesions on clinical outcome. METHODS: The data of patients included in the Italian PML cohort were retrospectively analysed. Patients who had all the pre-diagnostic MRI scans available (n = 37) were included. The volume of PML lesion was calculated by manually outlining the PML lesion. RESULTS: Compared with patients who underwent MRI examination at least every 4 months, patients who were assessed less frequently had a lesion of significantly higher volume (median: 2567 (883-3583) vs. 664 mm3 (392-963) p = 0.006) and suffered a higher rate of disability (median: 2.25 expanded disability status scale points (-2.5 to 8) vs. 0.5 (-1 to 2.5) p = 0.004). CONCLUSION: The positive clinical outcome of patients undergoing frequent MRI surveillance and the small volume of the PML lesion upon first appearance justify a frequent surveillance using MRI in patients at high risk of PML.

Inflammatory intrathecal profiles and cortical damage in multiple sclerosis.

OBJECTIVE: Gray matter (GM) damage and meningeal inflammation have been associated with early disease onset and a more aggressive disease course in multiple sclerosis (MS), but can these changes be identified in the patient early in the disease course? METHODS: To identify possible biomarkers linking meningeal inflammation, GM damage, and disease severity, gene and protein expression were analyzed in meninges and cerebrospinal fluid (CSF) from 27 postmortem secondary progressive MS and 14 control cases. Combined cytokine/chemokine CSF profiling and 3T magnetic resonance imaging (MRI) were performed at diagnosis in 2 independent cohorts of MS patients (35 and 38 subjects) and in 26 non-MS patients. RESULTS: Increased expression of proinflammatory cytokines (IFNγ, TNF, IL2, and IL22) and molecules related to sustained B-cell activity and lymphoid-neogenesis (CXCL13, CXCL10, LTα, IL6, and IL10) was detected in the meninges and CSF of postmortem MS cases with high levels of meningeal inflammation and GM demyelination. Similar proinflammatory patterns, including increased levels of CXCL13, TNF, IFNγ, CXCL12, IL6, IL8, and IL10, together with high levels of BAFF, APRIL, LIGHT, TWEAK, sTNFR1, sCD163, MMP2, and pentraxin III, were detected in the CSF of MS patients with higher levels of GM damage at diagnosis. INTERPRETATION: A common pattern of intrathecal (meninges and CSF) inflammatory profile strongly correlates with increased cortical pathology, both at the time of diagnosis and at death. These results suggest a role for detailed CSF analysis combined with MRI as a prognostic marker for more aggressive MS. Ann Neurol 2018 Ann Neurol 2018;83:739-755.

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.

Impact of natural menopause on multiple sclerosis: a multicentre study.

OBJECTIVE: To study the effect of natural menopause on multiple sclerosis clinical course. METHODS: This was an observational, retrospective, multicentre, cohort study. Menopause onset was defined by the final menstrual period (FMP) beyond which no menses occurred for 12 months. We included multiple sclerosis (MS) patients with FMP occurred after 2005 and a recorded follow-up of at least 2 years pre-FMP and post-FMP. We excluded patients with primary progressive course, iatrogenic menopause and with other confounders that could mask menopause onset. We compared relapse-rate and expanded disability status scale (EDSS) scores pre-FMP and post-FMP, searching for possible interactions with age, disease duration, cigarette smoking and nulliparity status. RESULTS: 148 patients were included (mean observation: 3.5 years pre-FMP and post-FMP). Most patients (92%) received disease-modifying therapies, mainly first-lines. After menopause the annualised relapse rate (ARR) significantly decreased (from 0.21±0.31 to 0.13± 0.24; p=0.005), while disability worsened (increase of mean 0.4 vs 0.2 points after menopause; p<0.001). Older age and long-lasting disease were associated with ARR reduction (p=0.013), but not with disability worsening. Cigarette smokers showed a trend to a higher disability accumulation after menopause (p=0.059). CONCLUSION: Natural menopause seems to be a turning point to a more progressive phase of MS. Relapse rate is also reduced after menopause, but this effect could be driven most by ageing and shifting to progressive phase in patients with long-lasting disease. Cigarette smoking could speed up disability progression after menopause.

Immune profiling of a patient with alemtuzumab-associated progressive multifocal leukoencephalopathy.

A 31-year-old woman affected by multiple sclerosis (MS) experienced generalized tonic-clonic seizures 2 months after the second alemtuzumab cycle. Positive JC virus (JCV)-DNA in cerebrospinal fluid (CSF) and lesion iconography at magnetic resonance imaging (MRI) were suggestive of progressive multifocal leukoencephalopathy (PML). After 1 month, during full-blown immune reconstitution inflammatory syndrome, JCV-DNA became negative and symptoms gradually improved. New T- and B-cell output and T- and B-cell diversity were low and lymphocytes poorly responded to stimulation. This is the first case of an alemtuzumab-treated patient with clinical symptoms and radiological features compatible with PML. The lack of large T- and B-cell diversity, necessary for JCV recognition, is likely to have concurred to PML insurgence.

Four cases of natalizumab-related PML: a less severe course in extended interval dosing?

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a severe adverse event of natalizumab (NTZ). The administration of NTZ with extended interval dosing (EID) has been proposed as a strategy to potentially reduce the incidence of PML while maintaining its therapeutic efficacy. METHODS: In the current paper, we describe 4 cases of NTZ-PML in EID included in the Italian PML cohort. RESULTS: The patients developed PML after at least 38 NTZ infusions. Their John Cunningham virus (JCv) index was > 1.5, and patients had not previously used immunosuppressant. Two patients were asymptomatic at PML onset, while two had mild motor impairment of the right hand and anomia, respectively. All of them had undetectable viral load but one (37 JCv copies/ml). In all patients, MRI revealed unilobar lesions with deferred contrast enhancement suggestive of immune reconstitution. The clinical course ended with a favorable clinical outcome (ΔEDSS up to 1). CONCLUSIONS: Although PML in EID seems to occur less frequently than in conventional dosing regimen, strict monitoring of high-risk patients contributed to the indolent course observed in the four described cases, characterized by a prolonged pre-symptomatic phase, paucisymptomatic onset, low JCv load, less severe functional impairment during immune reconstitution, and a mild disability burden.

To do or not to do? plasma exchange and timing of steroid administration in progressive multifocal leukoencephalopathy.

OBJECTIVE: To retrospectively analyze the effect of plasma exchange (PLEX; yes = PLEX+ , no = PLEX- ) and steroids administration timing (prophylactically [proST] or therapeutically [therST]) on the longitudinal clinical course of patients with natalizumab-related progressive multifocal leukoencephalopathy (PML) and full-blown immune reconstitution inflammatory syndrome (PML-IRIS). METHODS: Clinical and radiological data of 42 Italian patients with PML were analyzed. Patient's data are available until 12 months after PML diagnosis. PLEX and steroids treatment as time-dependent covariates were entered in: (1) a Cox model to investigate their impact on full-blown PML-IRIS latency; (2) an analysis of variance ANOVA to investigate their impact on IRIS duration; and (3) a linear mixed model to assess their impact on the longitudinal clinical course (measured by means of Expanded Disability Status Scale [EDSS]). RESULTS: Treatment with PLEX was not associated to PML-IRIS latency (hazard ratio [HR] = 1.05; p = 0.92), but once IRIS emerged, its duration was significantly longer in patients who underwent PLEX (101 vs 54 days in PLEX+ and PLEX- patients; p = 0.028). Receiving proST versus therST was not associated to IRIS latency (HR = 0.67; p = 0.39) or duration (p = 0.95). Patients who underwent proST had a significantly higher EDSS increase during PML (0.09 EDSS points per month; p = 0.04) as compared to those who had therST. INTERPRETATION: This study highlights that: (1) caution on the use of PLEX should be considered as the current data do not support a beneficial effect of PLEX and (2) caution on the early use of steroids is suggested because their prophylactic use to prevent full-blown PML-IRIS seems to negatively impact on the longitudinal disability course. Ann Neurol 2017;82:697-705.

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.