Safety, tolerability, and activity of mesenchymal stem cells versus placebo in multiple sclerosis (MESEMS): a phase 2, randomised, double-blind crossover trial.

BACKGROUND: Mesenchymal stem cells (MSCs), also known as mesenchymal stromal cells, have been proposed as a promising therapeutic option for people with multiple sclerosis on the basis of their immunomodulatory and neuroprotective properties. The MEsenchymal StEm cells for Multiple Sclerosis (MESEMS) study was devised to evaluate the safety, tolerability, and activity of autologous MSCs derived from bone marrow and infused intravenously in patients with active multiple sclerosis. METHODS: MESEMS is a randomised phase 2 trial done at 15 sites in nine countries. Patients (aged 18-50 years) with active relapsing-remitting or progressive multiple sclerosis were included if they had a disease duration of 2-15 years since onset of multiple sclerosis and an Expanded Disability Status Scale score of 2·5-6·5. Patients were randomly assigned (1:1), according to a crossover design, to receive a single intravenous dose of autologous bone marrow-derived MSCs followed by placebo at week 24, or to receive placebo followed by autologous MSCs at week 24, with a follow-up visit at week 48. Primary objectives were to test safety and activity of MSC treatment. The primary safety endpoint was to assess the number and severity of adverse events within each treatment arm. The primary efficacy endpoint was the number of gadolinium-enhancing lesions (GELs) counted over week 4, 12, and 24 compared between treatment groups. The primary efficacy endpoint was assessed in the full analyis set, after all participants completed the week 24 visit. Efficacy endpoints were evaluated using a predefined statistical testing procedure. Safety was monitored throughout the study by recording vital signs and adverse events at each visit. FINDINGS: From July 16, 2012, until July 31, 2019, 144 patients were randomly assigned to first receive early intravenous infusion of autologous bone marrow-derived MSCs (n=69) or placebo (n=75). MSC treatment did not meet the primary endpoint of efficacy on the total number of GELs accumulated from baseline to week 24 (rate ratio [RR] 0·94, 95% CI 0·58-1·50; p=0·78). 213 adverse events were recorded, similarly distributed between groups (93 cases recorded in 35 [51%] of 69 patients treated first with MSCs vs 120 cases in 42 [56%] of 75 patients infused first with placebo). The most frequent adverse events reported were infection and infestations, with a total of 54 (25%) of 213 adverse events (18 [19%] of 93 in the early-MSC group and 36 [30%] of 120 in the delayed-MSC group). Nine serious adverse events were reported in seven patients treated with placebo versus none in the MSC group. All serious adverse events were considered to be unrelated to the treatment infusion. No deaths were reported during the study. INTERPRETATION: Bone marrow-derived MSC treatment was safe and well tolerated but did not show an effect on GELs, an MRI surrogate marker of acute inflammation, in patients with active forms of multiple sclerosis, at week 24. Thus, this study does not support the use of bone marrow-derived MSCs to treat active multiple sclerosis. Further studies should address the effect of MSCs on parameters related to tissue repair. FUNDING: Fondazione Italiana Sclerosi Multipla (FISM), the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS), and the Multiple Sclerosis International Federation (MSIF) for centralised activities. Individual trials participating in the MESEMS network are funded by the following agencies: FISM and Compagnia di San Paolo (Italy); The Danish Multiple Sclerosis Society, The Toyota Foundation, and Danish Blood Donors' Research Foundation (Denmark); the Spanish Health Research Institute Carlos 3 and the Andalusian Public Foundation Progreso y Salud (Spain); the Royan Institute for Stem Cell Biology and Technology (Iran); the Spinal Cord Injury and Tissue Regeneration Centre Salzburg, Paracelsus Medical University, and Salzburg (Austria); the Fondation pour l'aide à la recherche sur la sclérose en plaques (ARSEP), French Muscular Dystrophy Association (AFM)-Telethon (France); the UK Multiple Sclerosis Society and the UK Stem Cell Foundation (UK); and the Multiple Sclerosis Society of Canada and The Multiple Sclerosis Scientific Research Foundation and Research Manitoba (Canada).

Basket clinical trial design for targeted therapies for cancer: a French National Authority for Health statement for health technology assessment.

During the past decade, health technology assessment bodies have faced new challenges in establishing the benefits of new drugs for individuals and health-care systems. A topic of increasing importance to the field of oncology is the so-called agnostic regulatory approval of targeted therapies for cancer (independent of tumour location and histology) granted on the basis of basket trials. Basket trials in oncology offer the advantage of simultaneously evaluating treatments for multiple tumours, even rare cancers, in a single clinical trial. To address the novel challenges introduced by these trials, an interdisciplinary panel was convened on behalf of the Transparency Committee of the French National Authority for Health to clarify an approach designed to guarantee a transparent, reproducible, and fair assessment of histology-agnostic treatments for reimbursement by the French National Health Insurance Fund. The requirements of this approach include the need for randomisation, clinically relevant endpoints, appropriate correction for multiple significance testing, characterisation of subgroup heterogeneity, and validation of underlying biomarker assays. A prospectively designated external control is encouraged when the implementation of a direct comparison is deemed infeasible. We also underline the importance of recording outcomes from basket trials in a registry for use as future external controls.

Association of Central Hypersomnia and Fatigue in Patients With Multiple Sclerosis: A Polysomnographic Study.

OBJECTIVE: To evaluate sleepiness and central hypersomnia in multiple sclerosis (MS)-associated fatigue, we performed long-term polysomnography in patients with MS and healthy controls. METHODS: Patients with MS and healthy controls completed questionnaires on sleep, fatigue, sleepiness, and depression. They underwent nocturnal polysomnography, multiple sleep latency tests, and bed rest 24-hour polysomnography. Patients were divided into 3 groups (fatigue and sleepiness, fatigue and no sleepiness, neither fatigue nor sleepiness). RESULTS: Among 44 patients with MS, 19 (43.2%) had fatigue and sleepiness, 15 (34%) had only fatigue, and 10 (22.7%) had neither fatigue nor sleepiness. Compared to 24 controls, patients with fatigue and sleepiness had higher REM sleep percentages (median [interquartile range] 20.5% [19.6-24.7] vs 18.1% [12.6-20.6]), lower arousal indexes (12.7 [7.5-17.0] vs 22.4 [14.3-34.4]), and shorter daytime mean sleep latencies (8.6 [6.3-14.3] vs 16.6 [12.6-19.5] min). Restless leg syndrome, periodic leg movements, and sleep apnea had similar frequencies between groups. Central hypersomnia was found in 10 (53%) patients with fatigue and sleepiness (narcolepsy type 2, n = 2), in 2 (13%) patients with fatigue only, and in 3 (30%) patients with neither fatigue nor sleepiness. Patients with central hypersomnia were younger and sleepier than those without hypersomnia, but had similar levels of fatigue, disability, depression, cognitive performance, and frequencies of the human leukocyte antigen DQB1*0602 genotype. The severity of fatigue increased with higher depression scores, higher sleepiness severity, and lower sleep efficacy. CONCLUSION: Central hypersomnias are frequent in MS when fatigue and sleepiness are present. Screening them through polysomnography studies is recommended.

Observatoire Français de la Sclérose en Plaques (OFSEP): A unique multimodal nationwide MS registry in France.

The care of multiple sclerosis (MS) in France is based on two complementary interlinked networks: MS expert centers in university hospitals and regional networks of neurologists. The routine use of European database for multiple sclerosis (EDMUS) in all those centers has paved the way for the constitution of a national registry, designated as Observatoire Français de la Sclérose En Plaques (OFSEP). It promotes a prospective, standardized, high-quality, and multimodal collection of data. On June 2018, there were 68.097 files, with 71.1% females, representing 761,185 person-years. This huge database is open to the scientific community and might contribute exploring unresolved issues and unmet needs in MS.

MEsenchymal StEm cells for Multiple Sclerosis (MESEMS): a randomized, double blind, cross-over phase I/II clinical trial with autologous mesenchymal stem cells for the therapy of multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is an inflammatory disease of the central nervous system with a degenerative component, leading to irreversible disability. Mesenchymal stem cells (MSC) have been shown to prevent inflammation and neurodegeneration in animal models of MS, but no large phase II clinical trials have yet assessed the exploratory efficacy of MSC for MS. METHODS/DESIGN: This is an academic, investigator-initiated, randomized, double-blind, placebo-compared phase I/II clinical trial with autologous, bone-marrow derived MSC in MS. Enrolled subjects will receive autologous MSC at either baseline or at week 24, through a cross-over design. Primary co-objectives are to test safety and efficacy of MSC treatment compared to placebo at 6 months. Secondary objectives will evaluate the efficacy of MSC at clinical and MRI levels. In order to overcome funding constraints, the MEsenchymal StEm cells for Multiple Sclerosis (MESEMS) study has been designed to merge partially independent clinical trials, following harmonized protocols and sharing some key centralized procedures, including data collection and analyses. DISCUSSION: Results will provide patients and the scientific community with data on the safety and efficacy of MSC for MS. The innovative approach utilized to obtain funds to support the MESEMS trial could represent a new model to circumvent limitation of funds encountered by academic trials. TRIAL REGISTRATION: Andalusia: NCT01745783 , registered on Dec 10, 2012. Badalona: NCT02035514 EudraCT, 2010-024081-21. Registered on 2012. Canada: ClinicalTrials.gov, NCT02239393 . Registered on September 12, 2014. Copenhagen: EudraCT, 2012-000518-13 . Registered on June 21, 2012. Italy: EudraCT, 2011-001295-19, and ClinicalTrials.gov, NCT01854957 . Retrospectively registered on May 16, 2013. London: Eudra CT 2012-002357-35, and ClinicalTrials.gov, NCT01606215 . Registered on May 25, 2012. Salzburg: EudraCT, 2015-000137-78 . Registered on September 15, 2015. Stockholm: ClinicalTrials.gov, NCT01730547 . Registered on November 21, 2012. Toulouse: ClinicalTrials.gov, NCT02403947 . Registered on March 31, 2015.

Biallelic MYORG mutation carriers exhibit primary brain calcification with a distinct phenotype.

Primary familial brain calcification (PFBC) is a rare neurogenetic disorder with diverse neuropsychiatric expression. Mutations in four genes cause autosomal dominant PFBC: SLC20A2, XPR1, PDGFB and PDGFRB. Recently, biallelic mutations in the MYORG gene have been reported to cause PFBC with an autosomal recessive pattern of inheritance. We screened MYORG in 29 unrelated probands negatively screened for the autosomal dominant PFBC genes and identified 11 families with a biallelic rare or novel predicted damaging variant. We studied the clinical and radiological features of 16 patients of these 11 families and compared them to that of 102 autosomal dominant PFBC patients carrying a mutation in one of the four known autosomal dominant PFBC genes. We found that MYORG patients exhibited a high clinical penetrance with a median age of onset of 52 years (range: 21-62) with motor impairment at the forefront. In particular, dysarthria was the presenting sign in 11/16 patients. In contrast to patients with autosomal dominant PFBC, 12/15 (80%) symptomatic patients eventually presented at least four of the following five symptoms: dysarthria, cerebellar syndrome, gait disorder of any origin, akinetic-hypertonic syndrome and pyramidal signs. In addition to the most severe clinical pattern, MYORG patients exhibited the most severe pattern of calcifications as compared to the patients from the four autosomal dominant PFBC gene categories. Strikingly, 12/15 presented with brainstem calcifications in addition to extensive calcifications in other brain areas (lenticular nuclei, thalamus, cerebellar hemispheres, vermis, ±cortex). Among them, eight patients exhibited pontine calcifications, which were observed in none of the autosomal dominant PFBC patients and hence appeared to be highly specific. Finally, all patients exhibited cerebellar atrophy with diverse degrees of severity on CT scans. We confirmed the existence of cerebellar atrophy by performing MRI voxel-based morphometry analyses of MYORG patients with autosomal dominant PFBC mutation carriers as a comparison group. Of note, in three families, the father carried small pallido-dentate calcifications while carrying the mutation at the heterozygous state, suggesting a putative phenotypic expression in some heterozygous carriers. In conclusion, we confirm that MYORG is a novel major PFBC causative gene and that the phenotype associated with such mutations may be recognized based on pedigree, clinical and radiological features.

Cervical dysplasia in a patient with multiple sclerosis treated with natalizumab.

We describe one report of a cervical dysplasia in a patient receiving natalizumab for multiple sclerosis. Other cases were identified in the WHO's global individual case safety report database, VigiBase® . These data underline the importance of monitoring HPV infection in patients with MS treated with natalizumab.

Late-onset neutropenia and neurological relapse, during long-term rituximab therapy in myelin oligodendrocyte glycoprotein-antibody spectrum disorder.

Late-onset neutropenia after rituximab therapy (LONART) is defined as a fall in the absolute neutrophil count below 500/mm3 at least 3 weeks after rituximab infusion, in the absence of any other explanation. LONART is rare during dysimmune conditions but can be life-threatening. We report on two patients with LONART and associated neurological relapse occurring in myelin oligodendrocyte glycoprotein (MOG)-antibody spectrum disorders. Rituximab was reintroduced in one patient, while the second patient was switched to tocilizumab. LONART can occur during anti-MOG spectrum disorders. Neurologists should be aware of this rare and treatable complication. Regular monitoring of blood cell counts is needed, and patients should be informed of the need to consult their physician if symptoms of infection appear.

ECTRIMS/EAN Guideline on the pharmacological treatment of people with multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a complex disease with new drugs becoming available in the past years. There is a need for a reference tool compiling current data to aid professionals in treatment decisions. OBJECTIVES: To develop an evidence-based clinical practice guideline for the pharmacological treatment of people with MS. METHODS: This guideline has been developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology and following the updated EAN recommendations. Clinical questions were formulated in Patients-Intervention-Comparator-Outcome (PICO) format and outcomes were prioritized. The quality of evidence was rated into four categories according to the risk of bias. The recommendations with assigned strength (strong and weak) were formulated based on the quality of evidence and the risk-benefit balance. Consensus between the panelists was reached by use of the modified nominal group technique. RESULTS: A total of 10 questions were agreed, encompassing treatment efficacy, response criteria, strategies to address suboptimal response and safety concerns and treatment strategies in MS and pregnancy. The guideline takes into account all disease-modifying drugs approved by the European Medicine Agency (EMA) at the time of publication. A total of 21 recommendations were agreed by the guideline working group after three rounds of consensus. CONCLUSION: The present guideline will enable homogeneity of treatment decisions across Europe.

[Towards a national strategy on the diagnosis of neurocognitive disorders. A shared approach among the French National College of General Practitioners and specialists of neurocognitive disorders]. / Vers une stratégie nationale de diagnostic des troubles cognitifs. Approche commune du Collège de médecine générale et des spécialistes des troubles neurocognitifs.

Neurocognitive disorders leading to progressive cognitive, functional and behavioural impairment are often undiagnosed or diagnosed lately. But tailored care and therapeutics help in implementing secondary and tertiary prevention dynamics aiming at preserving quality of life and delaying, anticipating or preventing behavioural crisis and severe stages of dementia. Moreover, the diagnosis of numerous diseases induces specific care and therapeutics, as well access to research and clinical trials. For the first time, the representatives of the National College of General Practitioners, the French Federation of Memory Centres, the French Federation of Gerontology and Geriatrics, the French Federation of Neurology, the French Society of Psychogeriatrics and the national plan on neurodegenerative diseases propose a graduated and tailored diagnosis strategy involving primary care and specialists of neurocognitive disorders. This strategy has been built in the context of the national plan on neurodegenerative diseases, the European Joint Action "Act on dementia", and has been consensually agreed after a seminar animated by the National College of General Practitioners in March 2017.

Assessment of a program to encourage the multidisciplinary management of urinary disorders in multiple sclerosis.

AIMS: Urinary disorders (UD) secondary to multiple sclerosis (MS) are common and can be responsible for complications. Since 2004, we organized in our region their management through a neuro-urological activity and a care network that established and distributed an algorithm for screening and first line care. The objective was to assess the effects of this organization on the management of UD and its impact for patients. METHODS: Between January 2004 and December 2009, 328 patients were seen in neuro-urological consultation. The data of a group of 168 patients consulting during the deployment of our organization (before January 2007: group 1) were compared to those of 160 patients taken when the organization was well established (from January 2007: group 2). In parallel, the modification of the prescription rate of the first-line examination patients was evaluated. RESULTS: The two groups were significantly different concerning age, duration of MS, EDSS score (Group 1 vs. Group 2 respectively 51.6 ± 12.6 vs. 48 ± 11.8 years, P = 0.008; 19 ± 9.7 vs. 13.8 ± 10.5 years, P < 0.0001; 5.8 ±2.0 vs. 5.1 ± 2.1, P = 0.008). The occurrence of urinary complications in group 1 was more frequent than in group 2 (66.3% vs. 40%, P < 0.0001). The rate of first-line examinations rose from 1/16 patient seen in January 2006 to 9/12 patients in January 2008. CONCLUSION: The multidisciplinary management of UD in MS led to patients being cared for sooner in the evolution of MS, with fewer complications and to an improvement in the rate of prescription of first-line examinations. Neurourol. Urodynam. 36:706-709, 2017. © 2016 Wiley Periodicals, Inc.

Geographical Heterogeneity of Multiple Sclerosis Prevalence in France.

INTRODUCTION: Geographical variation in the prevalence of multiple sclerosis (MS) is controversial. Heterogeneity is important to acknowledge to adapt the provision of care within the healthcare system. We aimed to investigate differences in prevalence of MS in departments in the French territory. METHODS: We estimated MS prevalence on October 31, 2004 in 21 administrative departments in France (22% of the metropolitan departments) by using multiple data sources: the main French health insurance systems, neurologist networks devoted to MS and the Technical Information Agency of Hospitalization. We used a spatial Bayesian approach based on estimating the number of MS cases from 2005 and 2008 capture-recapture studies to analyze differences in prevalence. RESULTS: The age- and sex-standardized prevalence of MS per 100,000 inhabitants ranged from 68.1 (95% credible interval 54.6, 84.4) in Hautes-Pyrénées (southwest France) to 296.5 (258.8, 338.9) in Moselle (northeast France). The greatest prevalence was in the northeast departments, and the other departments showed great variability. DISCUSSION: By combining multiple data sources into a spatial Bayesian model, we found heterogeneity in MS prevalence among the 21 departments of France, some with higher prevalence than anticipated from previous publications. No clear explanation related to health insurance coverage and hospital facilities can be advanced. Population migration, socioeconomic status of the population studied and environmental effects are suspected.

Risk of relapse after natalizumab withdrawal: Results from the French TYSEDMUS cohort.

OBJECTIVE: To assess disease activity within 12 months after natalizumab (NZ) discontinuation in a large French postmarketing cohort. METHODS: In France, patients exposed at least once to NZ were included in the TYSEDMUS observational and multicenter cohort, part of the French NZ Risk Management Plan. Clinical disease activity during the year following NZ discontinuation was assessed in this cohort. Time to first relapse after NZ stop was analyzed using Kaplan-Meier method and potentially associated factors were studied using a multivariate Cox model. RESULTS: Out of the 4,055 patients with multiple sclerosis (MS) included in TYSEDMUS, 1,253 discontinued NZ and 715 of them had relevant data for our study. The probability of relapse within the year after NZ stop was estimated at 45% (95% confidence interval 0.41-0.49). CONCLUSIONS: This large and systematic survey of patients with MS after NZ withdrawal allows quantifying the risk of increased disease activity following treatment discontinuation. This study provides large-scale, multicenter, systematic data after NZ cessation in real-life settings.

MD1003 (high-dose biotin) for the treatment of progressive multiple sclerosis: A randomised, double-blind, placebo-controlled study.

BACKGROUND: Treatment with MD1003 (high-dose biotin) showed promising results in progressive multiple sclerosis (MS) in a pilot open-label study. OBJECTIVE: To confirm the efficacy and safety of MD1003 in progressive MS in a double-blind, placebo-controlled study. METHODS: Patients (n = 154) with a baseline Expanded Disability Status Scale (EDSS) score of 4.5-7 and evidence of disease worsening within the previous 2 years were randomised to 12-month MD1003 (100 mg biotin) or placebo thrice daily, followed by 12-month MD1003 for all patients. The primary endpoint was the proportion of patients with disability reversal at month 9, confirmed at month 12, defined as an EDSS decrease of ⩾1 point (⩾0.5 for EDSS 6-7) or a ⩾20% decrease in timed 25-foot walk time compared with the best baseline among screening or randomisation visits. RESULTS: A total of 13 (12.6%) MD1003-treated patients achieved the primary endpoint versus none of the placebo-treated patients (p = 0.005). MD1003 treatment also reduced EDSS progression and improved clinical impression of change compared with placebo. Efficacy was maintained over follow-up, and the safety profile of MD1003 was similar to that of placebo. CONCLUSION: MD1003 achieves sustained reversal of MS-related disability in a subset of patients with progressive MS and is well tolerated.

Excess Mortality in Patients with Multiple Sclerosis Starts at 20 Years from Clinical Onset: Data from a Large-Scale French Observational Study.

BACKGROUND: Recent studies in multiple sclerosis (MS) showed longer survival times from clinical onset than older hospital-based series. However estimated median time ranges widely, from 24 to 45 years, which makes huge difference for patients as this neurological disease mainly starts around age 20 to 40. Precise and up-to-date reference data about mortality in MS are crucial for patients and neurologists, but unavailable yet in France. OBJECTIVES: Estimate survival in MS patients and compare mortality with that of the French general population. METHODS: We conducted a multicenter observational study involving clinical longitudinal data from 30,413 eligible patients, linked to the national deaths register. Inclusion criteria were definite MS diagnosis and clinical onset prior to January, 1st 2009 in order to get a minimum of 1-year disease duration. RESULTS: After removing between-center duplicates and applying inclusion criteria, the final population comprised 27,603 MS patients (F/M sex ratio 2.5, mean age at onset 33.0 years, 85.5% relapsing onset). During the follow-up period (mean 15.2 +/- 10.3 years), 1569 deaths (5.7%) were identified; half related to MS. Death rates were significantly higher in men, patients with later clinical onset, and in progressive MS. Overall excess mortality compared with the general population was moderate (Standardized Mortality Ratio 1.48, 95% confidence interval [1.41-1.55]), but increased considerably after 20 years of disease (2.20 [2.10-2.31]). CONCLUSIONS: This study revealed a moderate decrease in life expectancy in MS patients, and showed that the risk of dying is strongly correlated to disease duration and disability, highlighting the need for early actions that can slow disability progression.

Urinary complications and risk factors in symptomatic multiple sclerosis patients. Study of a cohort of 328 patients.

AIMS: Lower urinary tract dysfunctions (LUTD) are very common in Multiple Sclerosis (MS), have a significant social impact, while the organic impact is discussed. We studied urinary complications and their risk factors in our cohort of MS patients, in order to improve the management of LUTD in MS. METHODS: Between 2004 and 2009, all patients affected by MS and managed for LUTD were included in a retrospective study. We studied the epidemiological data (age, gender), the clinical data (duration of MS, EDSS score, progression of MS) and the paraclinical data (urinary creatinine clearance, urine culture, urinary tract ultrasonography and in some cases urodynamic assessment and cystography). We then identified the urinary complications and their risk factors. RESULTS: Three hundred twenty eight patients, mean age 49.9 ± 12.3 years, with a MS for 14.3 ± 10 years on average and with a median EDSS score equal to 6 (1-9), were managed for LUTD. One hundred seventy eight (54%) patients developed one or more urinary complications. We identified duration of MS greater than 8.5 years and an EDSS above 7 as risk factors. CONCLUSION: Urinary complications are common in symptomatic MS, these results imply screening and specialized care to limit the impact on the quality of life but also to prevent urinary complications.

Adult-onset genetic leukoencephalopathies: a MRI pattern-based approach in a comprehensive study of 154 patients.

Inherited white matter diseases are rare and heterogeneous disorders usually encountered in infancy. Adult-onset forms are increasingly recognized. Our objectives were to determine relative frequencies of genetic leukoencephalopathies in a cohort of adult-onset patients and to evaluate the effectiveness of a systematic diagnostic approach. Inclusion criteria of this retrospective study were: (i) symmetrical involvement of white matter on the first available brain MRI; (ii) age of onset above 16 years. Patients with acquired diseases were excluded. Magnetic resonance imaging analysis identified three groups (vascular, cavitary and non-vascular/non-cavitary) in which distinct genetic and/or biochemical testing were realized. One hundred and fifty-four patients (male/female = 60/94) with adult-onset leukoencephalopathies were identified. Mean age of onset was 38.6 years. In the vascular group, 41/55 patients (75%) finally had a diagnosis [including CADASIL (cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy, n = 32) and COL4A1 mutation, n = 7]. In the cavitary group, 13/17 (76%) patients had a diagnosis of EIF2B-related disorder. In the third group (n = 82), a systematic biological screening allowed a diagnosis in 23 patients (28%) and oriented direct genetic screening identified 21 additional diseases (25.6%). Adult-onset genetic leukoencephalopathies are a rare but probably underestimated entity. Our study confirms the use of a magnetic resonance imaging-based classification with a final diagnosis rate of 64% (98/154) cases.