Genotypes and phenotypes of motor neuron disease: an update of the genetic landscape in Scotland.

BACKGROUND: Using the Clinical Audit Research and Evaluation of Motor Neuron Disease (CARE-MND) database and the Scottish Regenerative Neurology Tissue Bank, we aimed to outline the genetic epidemiology and phenotypes of an incident cohort of people with MND (pwMND) to gain a realistic impression of the genetic landscape and genotype-phenotype associations. METHODS: Phenotypic markers were identified from the CARE-MND platform. Sequence analysis of 48 genes was undertaken. Variants were classified using a structured evidence-based approach. Samples were also tested for C9orf72 hexanucleotide expansions using repeat-prime PCR methodology. RESULTS: 339 pwMND donated a DNA sample: 44 (13.0%) fulfilled criteria for having a pathogenic variant/repeat expansion, 53.5% of those with a family history of MND and 9.3% of those without. The majority (30 (8.8%)) had a pathogenic C9orf72 repeat expansion, including two with intermediate expansions. Having a C9orf72 expansion was associated with a significantly lower Edinburgh Cognitive and Behavioural ALS Screen ALS-Specific score (p = 0.0005). The known pathogenic SOD1 variant p.(Ile114Thr), frequently observed in the Scottish population, was detected in 9 (2.7%) of total cases but in 17.9% of familial cases. Rare variants were detected in FUS and NEK1. One individual carried both a C9orf72 expansion and SOD1 variant. CONCLUSIONS: Our results provide an accurate summary of MND demographics and genetic epidemiology. We recommend early genetic testing of people with cognitive impairment to ensure that C9orf72 carriers are given the best opportunity for informed treatment planning. Scotland is enriched for the SOD1 p.(Ile114Thr) variant and this has significant implications with regards to future genetically-targeted treatments.

Sporadic Creutzfeldt-Jakob disease in adults over 80 years: a 10-year review of United Kingdom surveillance.

INTRODUCTION: Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapidly progressive neurodegenerative disease with public health implications. Mean age of onset is 68 years. Age-specific incidence declines after 80 years. This may arise from under-ascertainment or other biological features of the disease. Accurate characterisation of late-onset sCJD is important for early diagnosis, avoiding unnecessary investigations and improving ascertainment for public health purposes. OBJECTIVE: To phenotype the clinical features and investigation profile of sCJD in adults >80 years. METHODS: We analysed all probable and definite sCJD cases identified by the UK National CJD Research & Surveillance Unit over a 10-year period (2011-2021). Individuals were grouped by age of onset. Clinical features and investigation profiles were compared. RESULTS: 10.3% (123/1196) had an age of onset over 80. Median survival was shorter (3.2 vs 4.3 months; P < 0.001). Pyramidal signs (48.3% vs 34.2%; P = 0.008) and akinetic mutism (55.1% vs 33.2%; P < 0.001) were more frequent. Psychiatric symptoms (26.3% vs 39.6%; P = 0.01) and cerebellar signs (65.4% vs 78.6%, P = 0.007) were less frequent. Cognitive impairment and myoclonus were highly prevalent regardless of age. Between age groups, the diagnostic sensitivity of cerebrospinal fluid real-time quaking-induced conversion (CSF RT-QuIC) (92.9% vs 91.9%, P = 0.74) was comparable, electroencephalography was superior (41.5% vs 25.4%; P = 0.006) and MRI was inferior (67.8% vs 91.4%; P < 0.001). CONCLUSIONS: Late-onset sCJD has distinct clinical features, shorter survival and a different profile of investigation sensitivity. CSF RT-QuIC, MRI brain and specialist CJD review is recommended in older adults with a rapidly progressive neurological disorder. Autopsy is valuable when the cause remains elusive.

Exploratory study to evaluate the acceptability of a wearable accelerometer to assess motor progression in motor neuron disease.

Motor neuron disease (MND) is a rapidly progressive condition traditionally assessed using a questionnaire to evaluate physical function, the revised amyotrophic lateral sclerosis functional rating scale (ALSFRS-R). Its use can be associated with poor sensitivity in detecting subtle changes over time and there is an urgent need for more sensitive and specific outcome measures. The ActiGraph GT9X is a wearable device containing multiple sensors that can be used to provide metrics that represent physical activity. The primary aim of this study was to investigate the initial suitability and acceptability of limb-worn wearable devices to group of people with MND in Scotland. A secondary aim was to explore the preliminary associations between the accelerometer sensor data within the ActiGraph GT9X and established measures of physical function. 10 participants with MND completed a 12-week schedule of assessments including fortnightly study visits, both in-person and over videoconferencing software. Participants wore the device on their right wrist and right ankle for a series of movements, during a 6-min walking test and for a period of 24-h wear, including overnight. Participants also completed an ALSFRS-R and questionnaires on their experience with the devices. 80% of the participants found wearing these devices to be a positive experience and no one reported interference with daily living or added burden. However, 30% of the participants experienced technical issues with their devices. Data from the wearable devices correlated with established measures of physical function.

Characterisation of RT-QuIC negative cases from the UK National CJD Research and Surveillance programme.

INTRODUCTION: Incorporation of the real-time quaking-induced conversion (RT-QuIC) assays for diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) has transformed diagnosis largely related to its extremely high specificity. However, the test has a c.10% false-negative result and we aim to characterize the clinical features, investigation profile, and molecular subtype in this cohort of patients. METHODS: 250 individuals diagnosed with definite sporadic CJD were identified from the UK National CJD Research and Surveillance Unit from 2012 to 2023. We compared the clinical features and investigation profile in those with a negative CSF RT-QuIC to those with a positive RT-QuIC. RESULTS: 27 individuals (10.8%) were CSF RT-QuIC negative. Median age of onset was younger (62 years vs 68 years, p = 0.002), median disease duration was longer (4.4 months vs 10.5 months, p < 0.001), and these individuals were less likely to present with gait difficulties (73% vs 93%, p = 0.003) or motor symptoms (62% vs 80%, p = 0.04). The sensitivity of electroencephalography and diffusion-weighted MRI were similar in both groups. In those who were RT-QuIC negative, there was an overrepresentation of the VV1 (32% vs 1%) and MM2 molecular subtypes (21% vs 3%). Co-occurring neurodegenerative disease was found in 33% (9/27) of those who were RT-QuIC negative. CONCLUSIONS: Individuals with sporadic CJD and a negative CSF RT-QuIC present with younger age of onset, different clinical features and are over-represented with the VV1 and MM2 subtypes of sporadic CJD. Further work is required to better understand the biochemical properties contributing to RT-QuIC negative results in these cases.

Non-motor symptoms in motor neuron disease: prevalence, assessment and impact.

People with motor neuron disease often experience non-motor symptoms that may occur secondary to, or distinct from, motor degeneration and that may significantly reduce quality of life, despite being under-recognized and evaluated in clinical practice. Non-motor symptoms explored in this population-based study include pain, fatigue, gastrointestinal issues, poor sleep, low mood, anxiety, problematic saliva, apathy, emotional lability, cognitive complaints and sexual dysfunction. People registered on the Clinical Audit Research and Evaluation of motor neuron disease platform, the Scottish Motor Neuron Disease Register, were invited to complete a questionnaire on non-motor symptoms and a self-reported Amyotrophic Lateral Sclerosis Functional Rating Scale. The questionnaire comprised a pre-defined list of 11 potential non-motor symptoms, with the opportunity to list additional symptoms. A total of 120 individuals participated in this cross-sectional study, a 39% response rate of those sent questionnaires (n = 311); 99% of participants recruited (n = 120) experienced at least one non-motor symptom, with 72% (n = 120) reporting five or more. The symptoms most often reported were pain and fatigue (reported by 76% of participants, respectively). The symptoms reported to be most impactful were gastrointestinal issues (reported as 'severe' by 54% of participants who experienced them), followed by pain and problematic saliva (51%, respectively). Lower Amyotrophic Lateral Sclerosis Functional Rating Scale scores, indicating more advanced disease and being a long survivor [diagnosed over 8 years ago; Black et al. (Genetic epidemiology of motor neuron disease-associated variants in the Scottish population. Neurobiol Aging. 2017;51:178.e11-178.e20.)], were significantly associated with reporting more symptoms; 73% of respondents were satisfied with the frequency that non-motor symptoms were discussed in clinical care; 80% of participants indicated they believe evaluation of non-motor symptom is important to include as outcomes in trials, independent of their personal experience of these symptoms. The preferred method of assessment was completing questionnaires, at home. The overwhelming majority of people with motor neuron disease report non-motor symptoms and these frequently co-occur. Pain, fatigue, gastrointestinal issues, sleep, mood, anxiety, problematic saliva, apathy, emotional lability, cognitive complaints and sexual dysfunction are prevalent. People with motor neuron disease who had worse physical function and those who were long survivors were more likely to report more symptoms. Where reported, these symptoms are frequent, impactful and a priority for people with motor neuron disease in clinical care and trial design.

The relationship between social cognitive processes and behavior changes in people with amnestic mild cognitive impairment or dementia using the Edinburgh Social Cognition Test (ESCoT).

OBJECTIVE: People with amnestic mild cognitive impairment (aMCI) or dementia often exhibit a decline in their social abilities, but few tests of social cognition exist that are suitable for clinical use. Moreover, the relationship between changes in behavior and impairments in social cognition is poorly understood. We examined the utility of the Edinburgh Social Cognition Test (ESCoT) in people with aMCI/dementia and explored associations between social cognition performance and behavior changes. METHOD: We administered the ESCoT and two established social cognition tests (the Reading the Mind in the Eyes and the Social Norms Questionnaire) to 28 people with aMCI or dementia and 28 age and sex matched cognitively healthy controls. Behavior change was measured using a semistructured interview which assesses behavioral abnormalities found in frontotemporal dementia. RESULTS: People with aMCI/dementia were impaired on the ESCoT affective theory of mind, ESCoT total score and the Reading the Mind in the Eyes. Behavior changes in the domains of apathy, loss of sympathy/empathy, perseveration, and psychotic symptoms were associated with poorer affective theory of mind scores. Disinhibition, loss of sympathy/empathy and hyperorality or altered food preferences were associated with cognitive theory of mind. All behaviors were significantly associated with poorer performance on ESCoT total score, but were not associated with performance on the Reading the Mind in the Eyes or the Social Norms Questionnaire. CONCLUSIONS: The ESCoT was sensitive to social cognition impairments in people with aMCI/dementia and it relates to behavior change in aMCI/dementia unlike established tests. Different subtests of the ESCoT were related to different behavior changes. These findings suggest that the ESCoT may be a clinically valuable tool when examining social cognition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Development, reliability, validity, and acceptability of the remote administration of the Edinburgh Cognitive and Behavioural ALS Screen (ECAS).

BACKGROUND: ALS clinical care and research has changed dramatically since the COVID-19 pandemic, accelerating the need for cognitive assessments to be adapted for remote use. OBJECTIVES: To develop the remote administration method of the Edinburgh Cognitive and Behavioural ALS Screen (ECAS), and determine its reliability and validity. Methods: The validation process consisted of: (1) Two versions of the ECAS (A and B) were administered, one in-person and one remotely via video call in a randomized order to 27 people without ALS; (2) The ECAS was administered remotely to 24 pwALS, with a second rater independently scoring performance; and (3) Acceptability was assessed by gathering feedback from 17 pwALS and 19 clinicians and researchers about their experience of using the ECAS remotely. RESULTS: In the group without ALS, the remote and in-person ECAS total scores were found to be equivalent, and a Bland-Altman plot showed good agreement between the two administration methods. In pwALS, there was excellent agreement between two raters (ICC = 0.99). Positive feedback was gained from pwALS, researchers and clinicians with regards to ease of process, convenience, time, and the environment. CONCLUSIONS: These findings provide evidence of the reliability and validity of the remote administration of the ECAS for pwALS, with clinicians, researchers and pwALS viewing it as a good alternative to face-to-face administration.

Factors impacting trial participation in people with motor neuron disease.

Motor neuron disease (MND) is a rapidly progressive neurodegenerative disorder with limited treatment options. Historically, neurological trials have been plagued by suboptimal recruitment and high rates of attrition. The Motor Neuron Disease-Systematic Multi-Arm Randomised Adaptive Trial (MND-SMART) seeks to identify effective disease modifying drugs. This study investigates person-specific factors affecting recruitment and retention. Improved understanding of these factors may improve trial protocol design, optimise recruitment and retention. Participants with MND completed questionnaires and this was supplemented with clinical data. 12 months after completing the questionnaires we used MND-SMART recruitment data to establish if members of our cohort engaged with the trial. 120 people with MND completed questionnaires for this study. Mean age at participation was 66 (SD = 9), 14% (n = 17) were categorised as long survivors, with 68% (n = 81) of participants male and 60% (n = 73) had the ALS sub-type. Of the 120 study participants, 50% (n = 60) were randomised into MND-SMART and 78% (n = 94) expressed interest an in participating. After the 1-year follow-up period 65% (n = 39) of the 60 randomised participants remained in MND-SMART. Older age was significantly associated with reduced likelihood of participation (OR = 0.92, 95% CI = 0.88-0.96, p = 0.000488). The findings show that people with MND are highly motivated to engage in research, but older individuals remain significantly less likely to participate. We recommend the inclusion of studies to explore characteristics of prospective and current participants alongside trials.

A systematic review and narrative analysis of digital speech biomarkers in Motor Neuron Disease.

Motor Neuron Disease (MND) is a progressive and largely fatal neurodegeneritve disorder with a lifetime risk of approximately 1 in 300. At diagnosis, up to 25% of people with MND (pwMND) exhibit bulbar dysfunction. Currently, pwMND are assessed using clinical examination and diagnostic tools including the ALS Functional Rating Scale Revised (ALS-FRS(R)), a clinician-administered questionnaire with a single item on speech intelligibility. Here we report on the use of digital technologies to assess speech features as a marker of disease diagnosis and progression in pwMND. Google Scholar, PubMed, Medline and EMBASE were systematically searched. 40 studies were evaluated including 3670 participants; 1878 with a diagnosis of MND. 24 studies used microphones, 5 used smartphones, 6 used apps, 2 used tape recorders and 1 used the Multi-Dimensional Voice Programme (MDVP) to record speech samples. Data extraction and analysis methods varied but included traditional statistical analysis, CSpeech, MATLAB and machine learning (ML) algorithms. Speech features assessed also varied and included jitter, shimmer, fundamental frequency, intelligible speaking rate, pause duration and syllable repetition. Findings from this systematic review indicate that digital speech biomarkers can distinguish pwMND from healthy controls and can help identify bulbar involvement in pwMND. Preliminary evidence suggests digitally assessed acoustic features can identify more nuanced changes in those affected by voice dysfunction. No one digital speech biomarker alone is consistently able to diagnose or prognosticate MND. Further longitudinal studies involving larger samples are required to validate the use of these technologies as diagnostic tools or prognostic biomarkers.

Cell-autonomous immune dysfunction driven by disrupted autophagy in C9orf72-ALS iPSC-derived microglia contributes to neurodegeneration.

Although microglial activation is widely found in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), the underlying mechanism(s) are poorly understood. Here, using human-induced pluripotent stem cell-derived microglia-like cells (hiPSC-MG) harboring the most common ALS/FTD mutation (C9orf72, mC9-MG), gene-corrected isogenic controls (isoC9-MG), and C9orf72 knockout hiPSC-MG (C9KO-MG), we show that reduced C9ORF72 protein is associated with impaired phagocytosis and an exaggerated immune response upon stimulation with lipopolysaccharide. Analysis of the C9ORF72 interactome revealed that C9ORF72 interacts with regulators of autophagy and functional studies showed impaired initiation of autophagy in mC9-MG and C9KO-MG. Coculture studies with motor neurons (MNs) demonstrated that the autophagy deficit in mC9-MG drives increased vulnerability of mC9-MNs to excitotoxic stimulus. Pharmacological activation of autophagy ameliorated both cell-autonomous functional deficits in hiPSC-MG and MN death in MG-MN coculture. Together, these findings reveal an important role for C9ORF72 in regulating immune homeostasis and identify dysregulation in myeloid cells as a contributor to neurodegeneration in ALS/FTD.

Systematic, comprehensive, evidence-based approach to identify neuroprotective interventions for motor neuron disease: using systematic reviews to inform expert consensus.

OBJECTIVES: Motor neuron disease (MND) is an incurable progressive neurodegenerative disease with limited treatment options. There is a pressing need for innovation in identifying therapies to take to clinical trial. Here, we detail a systematic and structured evidence-based approach to inform consensus decision making to select the first two drugs for evaluation in Motor Neuron Disease-Systematic Multi-arm Adaptive Randomised Trial (MND-SMART: NCT04302870), an adaptive platform trial. We aim to identify and prioritise candidate drugs which have the best available evidence for efficacy, acceptable safety profiles and are feasible for evaluation within the trial protocol. METHODS: We conducted a two-stage systematic review to identify potential neuroprotective interventions. First, we reviewed clinical studies in MND, Alzheimer's disease, Huntington's disease, Parkinson's disease and multiple sclerosis, identifying drugs described in at least one MND publication or publications in two or more other diseases. We scored and ranked drugs using a metric evaluating safety, efficacy, study size and study quality. In stage two, we reviewed efficacy of drugs in MND animal models, multicellular eukaryotic models and human induced pluripotent stem cell (iPSC) studies. An expert panel reviewed candidate drugs over two shortlisting rounds and a final selection round, considering the systematic review findings, late breaking evidence, mechanistic plausibility, safety, tolerability and feasibility of evaluation in MND-SMART. RESULTS: From the clinical review, we identified 595 interventions. 66 drugs met our drug/disease logic. Of these, 22 drugs with supportive clinical and preclinical evidence were shortlisted at round 1. Seven drugs proceeded to round 2. The panel reached a consensus to evaluate memantine and trazodone as the first two arms of MND-SMART. DISCUSSION: For future drug selection, we will incorporate automation tools, text-mining and machine learning techniques to the systematic reviews and consider data generated from other domains, including high-throughput phenotypic screening of human iPSCs.

Statistical analysis plan for the motor neuron disease systematic multi-arm adaptive randomised trial (MND-SMART).

BACKGROUND: MND-SMART is a platform, multi-arm, multi-stage, multi-centre, randomised controlled trial recruiting people with motor neuron disease. Initially, the treatments memantine and trazodone will each be compared against placebo, but other investigational treatments will be introduced into the trial later. The co-primary outcomes are the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALS-FRS-R) functional outcome, which is assessed longitudinally, and overall survival. METHODS: Initially in MND-SMART, participants are randomised 1:1:1 via a minimisation algorithm to receive placebo or one of the two investigational treatments with up to 531 to be randomised in total. The comparisons between each research arm and placebo will be conducted in four stages, with the opportunity to cease further randomisations to poorly performing research arms at the end of stages 1 or 2. The final ALS-FRS-R analysis will be at the end of stage 3 and final survival analysis at the end of stage 4. The estimands for the co-primary outcomes are described in detail. The primary analysis of ALS-FRS-R at the end of stages 1 to 3 will involve fitting a normal linear mixed model to the data to calculate a mean difference in rate of ALS-FRS-R change between each research treatment and placebo. The pairwise type 1 error rate will be controlled, because each treatment comparison will generate its own distinct and separate interpretation. This publication is based on a formal statistical analysis plan document that was finalised and signed on 18 May 2022. DISCUSSION: In developing the statistical analysis plan, we had to carefully consider several issues such as multiple testing, estimand specification, interim analyses, and statistical analysis of the repeated measurements of ALS-FRS-R. This analysis plan attempts to balance multiple factors, including minimisation of bias, maximising power and precision, and deriving clinically interpretable summaries of treatment effects. TRIAL REGISTRATION: EudraCT Number, 2019-000099-41. Registered 2 October 2019, https://www.clinicaltrialsregister.eu/ctr-search/search?query=mnd-smart ClinicalTrials.gov, NCT04302870 . Registered 10 March 2020.

Genotype-phenotype characterisation of long survivors with motor neuron disease in Scotland.

BACKGROUND: We investigated the phenotypes and genotypes of a cohort of 'long-surviving' individuals with motor neuron disease (MND) to identify potential targets for prognostication. METHODS: Patients were recruited via the Clinical Audit Research and Evaluation for MND (CARE-MND) platform, which hosts the Scottish MND Register. Long survival was defined as > 8 years from diagnosis. 11 phenotypic variables were analysed. Whole genome sequencing (WGS) was performed and variants within 49 MND-associated genes examined. Each individual was screened for C9orf72 repeat expansions. Data from ancestry-matched Scottish populations (the Lothian Birth Cohorts) were used as controls. RESULTS: 58 long survivors were identified. Median survival from diagnosis was 15.5 years. Long survivors were significantly younger at onset and diagnosis than incident patients and had a significantly longer diagnostic delay. 42% had the MND subtype of primary lateral sclerosis (PLS). WGS was performed in 46 individuals: 14 (30.4%) had a potentially pathogenic variant. 4 carried the known SOD1 p.(Ile114Thr) variant. Significant variants in FIG4, hnRNPA2B1, SETX, SQSTM1, TAF15, and VAPB were detected. 2 individuals had a variant in the SPAST gene suggesting phenotypic overlap with hereditary spastic paraplegia (HSP). No long survivors had pathogenic C9orf72 repeat expansions. CONCLUSIONS: Long survivors are characterised by younger age at onset, increased prevalence of PLS and longer diagnostic delay. Genetic analysis in this cohort has improved our understanding of the phenotypes associated with the SOD1 variant p.(Ile114Thr). Our findings confirm that pathogenic expansion of C9orf72 is likely a poor prognostic marker. Genetic screening using targeted MND and/or HSP panels should be considered in those with long survival, or early-onset slowly progressive disease, to improve diagnostic accuracy and aid prognostication.

Sporadic Creutzfeldt-Jakob Disease in the young (50 and below): 10-year review of United Kingdom surveillance.

INTRODUCTION: Sporadic Creutzfeldt-Jakob Disease (sCJD) is the commonest human prion disease, with a median age of onset of 68 years. We characterise the clinical, investigation, and neuropathological features in young individuals with sCJD using data from UK national CJD surveillance. METHODS: Referrals between 2011 and 2021 were examined, with definite (post-mortem confirmed) or probable sCJD cases included. Clinical features, MRI, EEG, CSF RT-QuIC, 14-3-3, PRNP sequencing and neuropathological findings were examined. We compared younger (≤ 50 years age of onset) with older individuals. Records of Non-sCJD referrals were also reviewed. RESULTS: 46 (4%) young individuals were identified (age at onset 25-50) from 1178 cases. 15 (33%) were autopsy confirmed. Psychiatric disturbance (37% vs 22%, p = 0.02) and headache (11% vs 3%, p = 0.01) at presentation, and longer disease duration (by 1.45 months, 95% CI 0.43-2.79, logrank p = 0.007) were commoner. CSF RT-QuIC showed lower sensitivity (82% vs 93%, p = 0.02). There was no difference in sensitivity of MR brain or CSF 14-3-3. There were no significant co-pathologies in autopsy-confirmed cases. For non-sCJD referrals, 41 cases were of other CJD subtypes, and 7 non-prion diagnoses. CONCLUSIONS: Young-onset sCJD is more likely to present with neuropsychiatric symptoms and headache, longer disease duration, and lower sensitivity of RT-QuIC. These findings may be driven by the underlying molecular subtypes. Our results guide the evaluation of younger individuals presenting with rapidly progressive cognitive, neuropsychiatric, and motor decline, and emphasise the need for additional vigilance for atypical features by clinicians and CJD surveillance programmes worldwide.

A systematic review of digital technology to evaluate motor function and disease progression in motor neuron disease.

Amyotrophic lateral sclerosis (ALS) is the most common subtype of motor neuron disease (MND). The current gold-standard measure of progression is the ALS Functional Rating Scale-Revised (ALS-FRS(R)), a clinician-administered questionnaire providing a composite score on physical functioning. Technology offers a potential alternative for assessing motor progression in both a clinical and research capacity that is more sensitive to detecting smaller changes in function. We reviewed studies evaluating the utility and suitability of these devices to evaluate motor function and disease progression in people with MND (pwMND). We systematically searched Google Scholar, PubMed and EMBASE applying no language or date restrictions. We extracted information on devices used and additional assessments undertaken. Twenty studies, involving 1275 (median 28 and ranging 6-584) pwMND, were included. Sensor type included accelerometers (n = 9), activity monitors (n = 4), smartphone apps (n = 4), gait (n = 3), kinetic sensors (n = 3), electrical impedance myography (n = 1) and dynamometers (n = 2). Seventeen (85%) of studies used the ALS-FRS(R) to evaluate concurrent validity. Participant feedback on device utility was generally positive, where evaluated in 25% of studies. All studies showed initial feasibility, warranting larger longitudinal studies to compare device sensitivity and validity beyond ALS-FRS(R). Risk of bias in the included studies was high, with a large amount of information to determine study quality unclear. Measurement of motor pathology and progression using technology is an emerging, and promising, area of MND research. Further well-powered longitudinal validation studies are needed.

Motor Neuron Disease Systematic Multi-Arm Adaptive Randomised Trial (MND-SMART): a multi-arm, multi-stage, adaptive, platform, phase III randomised, double-blind, placebo-controlled trial of repurposed drugs in motor neuron disease.

INTRODUCTION: Motor neuron disease (MND) is a rapidly fatal neurodegenerative disease. Despite decades of research and clinical trials there remains no cure and only one globally approved drug, riluzole, which prolongs survival by 2-3 months. Recent improved mechanistic understanding of MND heralds a new translational era with many potential targets being identified that are ripe for clinical trials. Motor Neuron Disease Systematic Multi-Arm Adaptive Randomised Trial (MND-SMART) aims to evaluate the efficacy of drugs efficiently and definitively in a multi-arm, multi-stage, adaptive trial. The first two drugs selected for evaluation in MND-SMART are trazodone and memantine. METHODS AND ANALYSIS: Initially, up to 531 participants (177/arm) will be randomised 1:1:1 to oral liquid trazodone, memantine and placebo. The coprimary outcome measures are the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALSFRS-R) and survival. Comparisons will be conducted in four stages. The decision to continue randomising to arms after each stage will be made by the Trial Steering Committee who receive recommendations from the Independent Data Monitoring Committee. The primary analysis of ALSFRS-R will be conducted when 150 participants/arm, excluding long survivors, have completed 18 months of treatment; if positive the survival effect will be inferentially analysed when 113 deaths have been observed in the placebo group. The trial design ensures that other promising drugs can be added for evaluation in planned trial adaptations. Using this novel trial design reduces time, cost and number of participants required to definitively (phase III) evaluate drugs and reduces exposure of participants to potentially ineffective treatments. ETHICS AND DISSEMINATION: MND-SMART was approved by the West of Scotland Research Ethics Committee on 2 October 2019. (REC reference: 19/WS/0123) Results of the study will be submitted for publication in a peer-reviewed journal and a summary provided to participants. TRIAL REGISTRATION NUMBERS: European Clinical Trials Registry (2019-000099-41); NCT04302870.

Concordance of cerebrospinal fluid real-time quaking-induced conversion across the European Creutzfeldt-Jakob Disease Surveillance Network.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) real-time quaking-induced conversion (RT-QuIC) has a high degree of sensitivity and specificity for the diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) and this has led to its being included in revised European CJD Surveillance Network diagnostic criteria for sCJD. As CSF RT-QuIC becomes more widely established, it is crucial that the analytical performance of individual laboratories is consistent. The aim of this ring-trial was to ascertain the degree of concordance between European countries undertaking CSF RT-QuIC. METHODS: Ten identical CSF samples, seven from probable or neuropathologically confirmed sCJD and three from non-CJD cases, were sent to 13 laboratories from 11 countries for RT-QuIC analysis. A range of instrumentation and different recombinant prion protein substrates were used. Each laboratory analysed the CSF samples blinded to the diagnosis and reported the results as positive or negative. RESULTS: All 13 laboratories correctly identified five of the seven sCJD cases and the remaining two sCJD cases were identified by 92% of laboratories. Of the two sCJD cases that were not identified by all laboratories, one had a disease duration >26 months with a negative 14-3-3, whilst the remaining case had a 4-month disease duration and a positive 14-3-3. A single false positive CSF RT-QuIC result was observed in this study. CONCLUSIONS: This study shows that CSF RT-QuIC demonstrates an excellent concordance between centres, even when using a variety of instrumentation, recombinant prion protein substrates and CSF volumes. The adoption of CSF RT-QuIC by all CJD surveillance centres is recommended.