Pregnancy in multiple sclerosis women with relapses in the year before conception increases the risk of long-term disability worsening.

BACKGROUND: The influence of pregnancy on long-term disability in multiple sclerosis (MS) is still controversial. OBJECTIVE: To assess the risk of long-term disability worsening after pregnancy in MS women as compared with a propensity-score (PS) matched group of MS women without pregnancy. METHODS: In the setting of the Italian Pregnancy Dataset, MS patients with (pregnancy group (PG)) and without pregnancy (control group (CG)) were recruited. Time to disability worsening on the Expanded Disability Status Scale (EDSS) was assessed through a multivariable Cox regression model. RESULTS: The PS-matching retained 230 PG and 102 CG patients. After a follow-up of 6.5 +/- 3.1 years, disability worsening occurred in 87 (26.2%) women. In the multivariable analysis, disability worsening was associated with pregnancy in women with relapses in the year before conception (adjusted hazard ratio (aHR) = 1.74; 95% confidence interval (CI) 1.06-2.84; p = 0.027), higher EDSS (aHR = 1.39; 95% CI 1.12-1.74; p = 0.003), younger age (aHR = 0.95; 95% CI 0.91-0.99; p = 0.022) and shorter DMD exposure over the follow-up (p < 0.008). CONCLUSION: Pregnancy in MS women with relapses in the year before conception increases the risk of long-term disability worsening. Our findings underscore the importance of counselling in MS women facing a pregnancy that should be planned after a period of clinical stability, favouring treatment optimization in patients with recent disease activity.

Natalizumab treatment and pregnancy in multiple sclerosis: A reappraisal of maternal and infant outcomes after 6 years.

OBJECTIVES: To assess the impact of timing of natalizumab cessation/redosing on long-term maternal and infant outcomes in 72 out of the original 74 pregnancies of the Italian Pregnancy Dataset in multiple sclerosis (MS). METHODS: Maternal outcomes in patients who received natalizumab until conception and restarted the drug within 1 month after delivery ("treatment approach," (TA)) and patients who stopped natalizumab before conception and/or restarted the drug later than 1 month after delivery ("conservative approach," (CA)) were compared through multivariable Cox regression analyses. Pediatric outcomes were assessed through a semi-structured questionnaire. RESULTS: After a mean follow-up of 6.1 years, CA (hazard ratio (HR) = 4.1, 95% CI 1.6-10.6, p = 0.003) was the only predictor of relapse occurrence. Worsening on the Expanded Disability Status Scale (EDSS) was associated with higher annualized relapse-rate during the follow-up (HR = 3.3, 95% CI 1.4-7.9 p = 0.007). We found no major development abnormalities in children. DISCUSSION: Our data confirm that TA reduces the risk of disease activity; we did not observe an increase in major development abnormalities in the child.

In vivo gradients of thalamic damage in paediatric multiple sclerosis: a window into pathology.

The thalamus represents one of the first structures affected by neurodegenerative processes in multiple sclerosis. A greater thalamic volume reduction over time, on its CSF side, has been described in paediatric multiple sclerosis patients. However, its determinants and the underlying pathological changes, likely occurring before this phenomenon becomes measurable, have never been explored. Using a multiparametric magnetic resonance approach, we quantified, in vivo, the different processes that can involve the thalamus in terms of focal lesions, microstructural damage and atrophy in paediatric multiple sclerosis patients and their distribution according to the distance from CSF/thalamus interface and thalamus/white matter interface. In 70 paediatric multiple sclerosis patients and 26 age- and sex-matched healthy controls, we tested for differences in thalamic volume and quantitative MRI metrics-including fractional anisotropy, mean diffusivity and T1/T2-weighted ratio-in the whole thalamus and in thalamic white matter, globally and within concentric bands originating from CSF/thalamus interface. In paediatric multiple sclerosis patients, the relationship of thalamic abnormalities with cortical thickness and white matter lesions was also investigated. Compared to healthy controls, patients had significantly increased fractional anisotropy in whole thalamus (f2 = 0.145; P = 0.03), reduced fractional anisotropy (f2 = 0.219; P = 0.006) and increased mean diffusivity (f2 = 0.178; P = 0.009) in thalamic white matter and a trend towards a reduced thalamic volume (f2 = 0.027; P = 0.058). By segmenting the whole thalamus and thalamic white matter into concentric bands, in paediatric multiple sclerosis we detected significant fractional anisotropy abnormalities in bands nearest to CSF (f2 = 0.208; P = 0.002) and in those closest to white matter (f2 range = 0.183-0.369; P range = 0.010-0.046), while we found significant mean diffusivity (f2 range = 0.101-0.369; P range = 0.018-0.042) and T1/T2-weighted ratio (f2 = 0.773; P = 0.001) abnormalities in thalamic bands closest to CSF. The increase in fractional anisotropy and decrease in mean diffusivity detected at the CSF/thalamus interface correlated with cortical thickness reduction (r range = -0.27-0.34; P range = 0.004-0.028), whereas the increase in fractional anisotropy detected at the thalamus/white matter interface correlated with white matter lesion volumes (r range = 0.24-0.27; P range = 0.006-0.050). Globally, our results support the hypothesis of heterogeneous pathological processes, including retrograde degeneration from white matter lesions and CSF-mediated damage, leading to thalamic microstructural abnormalities, likely preceding macroscopic tissue loss. Assessing thalamic microstructural changes using a multiparametric magnetic resonance approach may represent a target to monitor the efficacy of neuroprotective strategies early in the disease course.

Long-term follow-up (up to 11 years) of an Italian pediatric MS cohort treated with Natalizumab: a multicenter, observational study.

BACKGROUND: Natalizumab (NAT) has a strong impact on disease activity of aggressive pediatric multiple sclerosis (MS), with no difference in safety profile compared to adult MS. However, available data are limited by short follow-up. Our aim was to report long-term follow-up data (up to 11 years) of a large Italian pediatric MS cohort treated with NAT. MATERIALS AND METHODS: We retrospectively collected data of pediatric MS patients treated with NAT included in a previous study and prospectively followed in Italian MS centers. We compared disease activity pre, during, and post-NAT and we performed survival analyses of time to evidence of disease activity (EDA) during NAT, time to reach EDA post-NAT, and time to NAT discontinuation. RESULTS: Ninety-two patients were included from 19 MS centers in Italy. At NAT initiation, cohort's characteristics were as follows: 55 females; 14.7 ± 2.4 (mean ± SD) years of age; 34 naïve to disease modifying therapies; 1-year pre-NAT annualized relapse rate (ARR): 2.2 ± 1.2; EDSS (median [IQR]): 2.5 [2.0-3.0]; gadolinium-enhancing lesions: 2 [1-5]; 41 JCV positives. During NAT treatment (61.9 ± 35.2 mean infusions), ARR lowered to 0.08 ± 0.23 (p < 0.001), EDSS score to 1.5 [1.0-2.5] at last infusion (p < 0.001), and 51% patients had EDA (21% after 6 months of rebaseline). No serious adverse events were reported. Forty-nine patients discontinued NAT, mainly due to PML concern; the majority (29/49) had disease reactivation in the subsequent 12 months, of which three with a clinical rebound. CONCLUSION: NAT treatment maintains its high efficacy for a long time in pediatric MS patients, with no new safety issues.

Trial of Fingolimod versus Interferon Beta-1a in Pediatric Multiple Sclerosis.

BACKGROUND: Treatment of patients younger than 18 years of age with multiple sclerosis has not been adequately examined in randomized trials. We compared fingolimod with interferon beta-1a in this population. METHODS: In this phase 3 trial, we randomly assigned patients 10 to 17 years of age with relapsing multiple sclerosis in a 1:1 ratio to receive oral fingolimod at a dose of 0.5 mg per day (0.25 mg per day for patients with a body weight of ≤40 kg) or intramuscular interferon beta-1a at a dose of 30 µg per week for up to 2 years. The primary end point was the annualized relapse rate. RESULTS: Of a total of 215 patients, 107 were assigned to fingolimod and 108 to interferon beta-1a. The mean age of the patients was 15.3 years. Among all patients, there was a mean of 2.4 relapses during the preceding 2 years. The adjusted annualized relapse rate was 0.12 with fingolimod and 0.67 with interferon beta-1a (absolute difference, 0.55 relapses; relative difference, 82%; P<0.001). The key secondary end point of the annualized rate of new or newly enlarged lesions on T2-weighted magnetic resonance imaging (MRI) was 4.39 with fingolimod and 9.27 with interferon beta-1a (absolute difference, 4.88 lesions; relative difference, 53%; P<0.001). Adverse events, excluding relapses of multiple sclerosis, occurred in 88.8% of patients who received fingolimod and 95.3% of those who received interferon beta-1a. Serious adverse events occurred in 18 patients (16.8%) in the fingolimod group and included seizures (in 4 patients), infection (in 4 patients), and leukopenia (in 2 patients). Serious adverse events occurred in 7 patients (6.5%) in the interferon beta-1a group and included infection (in 2 patients) and supraventricular tachycardia (in 1 patient). CONCLUSIONS: Among pediatric patients with relapsing multiple sclerosis, fingolimod was associated with a lower rate of relapse and less accumulation of lesions on MRI over a 2-year period than interferon beta-1a but was associated with a higher rate of serious adverse events. Longer studies are required to determine the durability and safety of fingolimod in pediatric multiple sclerosis. (Funded by Novartis Pharma; PARADIGMS ClinicalTrials.gov number, NCT01892722 .).

The introduction of new medications in pediatric multiple sclerosis: Open issues and challenges.

Disease-modifying drugs (DMDs) for multiple sclerosis (MS) have been evaluated in pediatric patients in observational studies demonstrating a similar, even better clinical effect compared to adults, with a similar safety. Only fingolimod has been tested in a randomized controlled trial (RCT) and is approved for pediatric multiple sclerosis (ped-MS). Numerous methodological, practical, and ethical issues underline that RCTs are difficult to conduct in ped-MS. This also creates a lack of safety information. To facilitate the availability of new agents in ped-MS, we encourage to develop a different approach based on pharmacokinetic/pharmacodynamic studies to yield information on optimal doses and implementation of obligatory registries to obtain information on safety as primary endpoint.

Temporal profile of lymphocyte counts and relationship with infections with fingolimod therapy in paediatric patients with multiple sclerosis: Results from the PARADIGMS study.

BACKGROUND: Reduction in absolute lymphocyte count (ALC) is expected with fingolimod treatment. OBJECTIVE: To evaluate the effect of fingolimod 0.5 mg versus intramuscular interferon ß-1a (30 µg) on ALC and its relationship with infections in paediatric-onset multiple sclerosis (POMS) up to 4 years. METHODS: We assessed ALC at baseline, monthly till 3 months, and every 3 months (core phase) and with variable periodicity (extension phase) of Phase 3 PARADIGMS study (N = 215). Incidence rates (IRs) of infection-related adverse events (infAEs)/100 patient-years were analysed by on-study nadir ALC. RESULTS: With fingolimod, ALC rapidly reduced to 29.9%-34.4% of baseline values within 2 weeks and remained stable thereafter; no relevant changes observed with interferon. IRs of infAEs were 67.6 with fingolimod and 61.8 with interferon; IR ratios with respect to interferon, overall: 1.09, by nadir ALC 0.2-0.4 × 109/L: 1.13 and >0.4 × 109/L: 0.91. Three patients had a single episode of ALC <0.2 × 109/L (core phase). No opportunistic infections were observed and infection risk did not increase during the extension phase. CONCLUSION: In paediatric patients, the overall incidence of infections was comparable between fingolimod and interferon. No association was observed between nadir ALC and infections in POMS, although sample size may have been too small to rule an association.

Rituximab in patients with pediatric multiple sclerosis and other demyelinating disorders of the CNS: Practical considerations.

Anti-CD20 therapies have established efficacy in the treatment of immune-mediated neurological and non-neurological diseases. Rituximab, one of the first B-cell-directed therapies, is relatively inexpensive compared to newer anti-CD20 molecules, is available in many countries, and has been used off-label in pediatric patients with neuroimmune conditions. The objective of this paper is to describe the experience with rituximab in pediatric multiple sclerosis and other inflammatory immune-mediated disorders of the central nervous system (CNS), and to define a protocol for its use in clinical practice, in particular addressing doses, interval of administration, duration of treatment, and tests to perform at baseline and during follow-up.

Disease-modifying drugs can reduce disability progression in relapsing multiple sclerosis.

An ever-expanding number of disease-modifying drugs for multiple sclerosis have become available in recent years, after demonstrating efficacy in clinical trials. In the real-world setting, however, disease-modifying drugs are prescribed in patient populations that differ from those included in pivotal studies, where extreme age patients are usually excluded or under-represented. In this multicentre, observational, retrospective Italian cohort study, we evaluated treatment exposure in three cohorts of patients with relapsing-remitting multiple sclerosis defined by age at onset: paediatric-onset (≤18 years), adult-onset (18-49 years) and late-onset multiple sclerosis (≥50 years). We included patients with a relapsing-remitting phenotype, ≥5 years follow-up, ≥3 Expanded Disability Status Scale (EDSS) evaluations and a first neurological evaluation within 3 years from the first demyelinating event. Multivariate Cox regression models (adjusted hazard ratio with 95% confidence intervals) were used to assess the risk of reaching a first 12-month confirmed disability worsening and the risk of reaching a sustained EDSS of 4.0. The effect of disease-modifying drugs was assessed as quartiles of time exposure. We found that disease-modifying drugs reduced the risk of 12-month confirmed disability worsening, with a progressive risk reduction in different quartiles of exposure in paediatric-onset and adult-onset patients [adjusted hazard ratios in non-exposed versus exposed >62% of the follow-up time: 8.0 (3.5-17.9) for paediatric-onset and 6.3 (4.9-8.0) for adult-onset, P < 0.0001] showing a trend in late-onset patients [adjusted hazard ratio = 1.9 (0.9-4.1), P = 0.07]. These results were confirmed for a sustained EDSS score of 4.0. We also found that relapses were a risk factor for 12-month confirmed disability worsening in all three cohorts, and female sex exerted a protective role in the late-onset cohort. This study provides evidence that sustained exposure to disease-modifying drugs decreases the risk of disability accumulation, seemingly in a dose-dependent manner. It confirms that the effectiveness of disease-modifying drugs is lower in late-onset patients, although still detectable.

Effect of fingolimod on MRI outcomes in patients with paediatric-onset multiple sclerosis: results from the phase 3 PARADIGMS study.

OBJECTIVE: PARADIGMS demonstrated superior efficacy and comparable safety of fingolimod versus interferon ß-1a (IFN ß-1a) in paediatric-onset multiple sclerosis (PoMS). This study aimed to report all predefined MRI outcomes from this study. METHODS: Patients with multiple sclerosis (MS) (aged 10-<18 years) were randomised to once-daily oral fingolimod (n=107) or once-weekly intramuscular IFN ß-1a (n=108) in this flexible duration study. MRI was performed at baseline and every 6 months for up to 2 years or end of the study (EOS) in case of early treatment discontinuation/completion. Key MRI endpoints included the annualised rate of formation of new/newly enlarging T2 lesions, gadolinium-enhancing (Gd+) T1 lesions, new T1 hypointense lesions and combined unique active (CUA) lesions (6 months onward), changes in T2 and Gd+ T1 lesion volumes and annualised rate of brain atrophy (ARBA). RESULTS: Of the randomised patients, 107 each were treated with fingolimod and IFN ß-1a for up to 2 years. Fingolimod reduced the annualised rate of formation of new/newly enlarging T2 lesions (52.6%, p<0.001), number of Gd+ T1 lesions per scan (66.0%, p<0.001), annualised rate of new T1 hypointense lesions (62.8%, p<0.001) and CUA lesions per scan (60.7%, p<0.001) versus IFN ß-1a at EOS. The percent increases from baseline in T2 (18.4% vs 32.4%, p<0.001) and Gd+ T1 (-72.3% vs 4.9%, p=0.001) lesion volumes and ARBA (-0.48% vs -0.80%, p=0.014) were lower with fingolimod versus IFN ß-1a, the latter partially due to accelerated atrophy in the IFN ß-1a group. CONCLUSION: Fingolimod significantly reduced MRI activity and ARBA for up to 2 years versus IFN ß-1a in PoMS.

Correction to: Aging with multiple sclerosis: prevalence and profile of cognitive impairment.

The above article was published online with an error in author name's affiliation. The Author Claudia Niccolai has changed her affiliation to IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy.

Long-term follow-up of pediatric MS patients starting treatment with injectable first-line agents: A multicentre, Italian, retrospective, observational study.

BACKGROUND: Few data are available on very long-term follow-up of pediatric multiple sclerosis (MS) patients treated with disease modifying treatments (DMTs). OBJECTIVES: To present a long-term follow-up of a cohort of Pediatric-MS patients starting injectable first-line agents. METHODS: Data regarding treatments, annualized relapse rate (ARR), Expanded Disability Status Scale (EDSS) score, and serious adverse event were collected. Baseline characteristics were tested in multivariate analysis to identify predictors of disease evolution. RESULTS: In total, 97 patients were followed for 12.5 ± 3.3 years. They started therapy at 13.9 ± 2.1 years, 88 with interferons and 9 with copaxone. During the whole follow-up, 82 patients changed therapy, switching to immunosuppressors/second-line treatment in 58% of cases. Compared to pre-treatment phase, the ARR was significantly reduced during the first treatment (from 3.2 ± 2.6 to 0.7 ± 1.5, p < 0.001), and it remained low during the whole follow-up (0.3 ± 0.2, p < 0.001). At last observation, 40% had disability worsening, but EDSS score remained <4 in 89%. One patient died at age of 23 years due to MS. One case of natalizumab-related progressive multifocal encephalopathy (PML) was recorded. Starting therapy before 12 years of age resulted in a better course of disease in multivariate analysis. CONCLUSION: Pediatric-MS patients benefited from interferons/copaxone, but the majority had to switch to more powerful drugs. Starting therapy before 12 years of age could lead to a more favorable outcome.

Correction to: Cognitive assessment in multiple sclerosis-an Italian consensus.

In the original article, Maria Pia Amato's second affiliation was not included. The second affiliation is IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy. The correct affiliation is presented here.

Correction to: The Italian multiple sclerosis register.

Unfortunately in the original publication, the affiliation of the author Maria Pia Amato was incorrect. The author inadvertently missed out to include her second affiliation.

The Italian multiple sclerosis register.

The past decade has seen extraordinary increase in worldwide availability of and access to several large multiple sclerosis (MS) databases and registries. MS registries represent powerful tools to provide meaningful information on the burden, natural history, and long-term safety and effectiveness of treatments. Moreover, patients, physicians, industry, and policy makers have an active interest in real-world observational studies based on register data, as they have the potential to answer the questions that are most relevant to daily treatment decision-making. In 2014, the Italian MS Foundation, in collaboration with the Italian MS clinical centers, promoted and funded the creation of the Italian MS Register, a project in continuity with the existing Italian MS Database Network set up from 2001. Main objective of the Italian MS Register is to create an organized multicenter structure to collect data of all MS patients for better defining the disease epidemiology, improving quality of care, and promoting research projects in high-priority areas. The aim of this article is to present the current framework and network of the Italian MS register, including the methodology used to improve the quality of data collection and to facilitate the exchange of data and the collaboration among national and international groups.

Aging with multiple sclerosis: prevalence and profile of cognitive impairment.

BACKGROUND: The increase in life expectancy of patients with multiple sclerosis (MS) requires a better knowledge of disease features in the older patients group. OBJECTIVE: To describe the prevalence and profile of cognitive impairment (CI) in older patients with MS and perform a comparison with younger patients. METHODS: Patients were consecutively recruited for 6 months. Cognitive performance was assessed through the Brief Repeatable Battery and the Stroop Test. CI was defined as impairment in ≥ 2 cognitive domains. RESULTS: We identified 111 patients older than 55 years (mean age 59.7 years). The prevalence of CI was 77.4%, which was significantly higher than in younger patients (42.8%; p < 0.01). Information processing speed was the most impaired domain (68.8%), followed by verbal learning (49.5%), executive function (47.7%), and visuospatial learning (26.6%). We found no significant differences in the prevalence of impairment in the distinct cognitive domains between older and younger patients with CI. Depression and fatigue were not associated with increased CI among patients in the older age group (p > 0.70). CONCLUSION: There is a remarkably high frequency of CI in older patients with MS. The similar profile of CI between older and younger patients suggests that CI is mostly directly related to MS itself and not to comorbid age-related disorders.

Prognostic indicators in pediatric clinically isolated syndrome.

OBJECTIVE: To assess prognostic factors for a second clinical attack and a first disability-worsening event in pediatric clinically isolated syndrome (pCIS) suggestive of multiple sclerosis (MS) patients. METHODS: A cohort of 770 pCIS patients was followed up for at least 10 years. Cox proportional hazard models and Recursive Partitioning and Amalgamation (RECPAM) tree-regression were used to analyze data. RESULTS: In pCIS, female sex and a multifocal onset were risk factors for a second clinical attack (hazard ratio [HR], 95% confidence interval [CI] = 1.28, 1.06-1.55; 1.42, 1.10-1.84, respectively), whereas disease-modifying drug (DMD) exposure reduced this risk (HR, 95% CI = 0.75, 0.60-0.95). After pediatric onset MS (POMS) diagnosis, age at onset younger than 15 years and DMD exposure decreased the risk of a first Expanded Disability Status Scale (EDSS)-worsening event (HR, 95% CI = 0.59, 0.42-0.83; 0.75, 0.71-0.80, respectively), whereas the occurrence of relapse increased this risk (HR, 95% CI = 5.08, 3.46-7.46). An exploratory RECPAM analysis highlighted a significantly higher incidence of a first EDSS-worsening event in patients with multifocal or isolated spinal cord or optic neuritis involvement at onset in comparison to those with an isolated supratentorial or brainstem syndrome. A Cox regression model including RECPAM classes confirmed DMD exposure as the most protective factor against EDSS-worsening events and relapses as the most important risk factor for attaining EDSS worsening. INTERPRETATION: This work represents a step forward in identifying predictors of unfavorable course in pCIS and POMS and supports a protective effect of early DMD treatment in preventing MS development and disability accumulation in this population. Ann Neurol 2017;81:729-739.

Patients with paediatric-onset multiple sclerosis are at higher risk of cognitive impairment in adulthood: An Italian collaborative study.

BACKGROUND: Patients with paediatric-onset multiple sclerosis (POMS) could be at an increased risk for cognitive impairment (CI), given the potential harmful effects of disease activity in neurodevelopment. However, there is scarce information on their long-term cognitive outcomes. OBJECTIVE: To compare the prevalence and profile of CI between adults with a history of POMS and those with classic, adult-onset multiple sclerosis (AOMS). METHODS: Cognitive performance was assessed through the Brief Repeatable Battery (BRB) and the Stroop Test in consecutive patients referred to six Italian MS centres. CI was defined as impairment in ⩾2 cognitive domains. RESULTS: In all, 119 patients with POMS and 712 with AOMS were included in this analysis. The prevalence of CI was 48.0% in AOMS, 44.5% in POMS; with similar neuropsychological profile between the two groups. However, when adjusting for current age, we found a significantly increased risk for CI (odds ratio (OR) = 1.71; p = 0.02) and for impairment in information processing speed (OR = 1.86; p < 0.01) in patients with POMS. A higher Expanded Disability Status Scale (EDSS) was also identified in POMS ( p = 0.03) compared with AOMS patients. CONCLUSION: Patients with a history of POMS appear to be at higher risk of physical and cognitive disability than AOMS patients, after correcting for age effects, with particular involvement of information processing speed.

Half-dose fingolimod for treating relapsing-remitting multiple sclerosis: Observational study.

OBJECTIVES: To investigate the efficacy and safety of fingolimod (FTY) 0.5 mg administered every other day (FTY-EOD) compared to every day (FTY-ED) in multiple sclerosis patients. METHODS: Multicentre retrospective observational study. Clinical, laboratory and neuroimaging data were consecutively collected from 60 FTY-EOD and 63 FTY-ED patients. Baseline characteristics were compared using logistic regression. Efficacy in preventing occurrence of relapses and demyelinating lesions was tested using propensity score-adjusted Cox and linear regressions. RESULTS: Weight was inversely associated with risk of switch to FTY-EOD because of any reason (odds ratio (OR) = 0.94, 95% confidence interval (95% CI) = 0.89-0.99, p = 0.026), and female sex and lower baseline lymphocyte count were positively associated with switch because of lymphopenia. Compared to FTY-ED patients, FTY-EOD patients were at higher risk of developing relapses (hazard ratio (HR) = 2.98, 95% CI = 1.07-8.27, p = 0.036) and either relapses or new magnetic resonance imaging (MRI) demyelinating lesions (combined outcome, HR = 2.07, 95% CI = 1.06-4.08, p = 0.034). Within FTY-EOD, treatment with natalizumab before FTY and lower age were positively associated with risk of developing relapses and combined outcome, respectively (HR = 25.71, 95% CI = 3.03-217.57, p = 0.002 and HR = 0.85, 95% CI = 0.77-0.96, p = 0.005). FTY-EOD was overall well tolerated. CONCLUSION: Disease reactivation was observed in a significant proportion of patients treated with FTY-EOD. Neurologists should be cautious when reducing FTY administration to every other day, especially in younger patients and those previously treated with natalizumab.