TRICALS: creating a highway toward a cure

Automated speech analytics in ALS: higher sensitivity of digital articulatory precision over the ALSFRS-R

Objective: Although studies have shown that digital measures of speech detected ALS speech impairment and correlated with the ALSFRS-R speech item, no study has yet compared their performance in detecting speech changes. In this study, we compared the performances of the ALSFRS-R speech item and an algorithmic speech measure in detecting clinically important changes in speech. Importantly, the study was part of a FDA submission which received the breakthrough device designation for monitoring ALS; we provide this paper as a roadmap for validating other speech measures for monitoring disease progression. Methods: We obtained ALSFRS-R speech subscores and speech samples from participants with ALS. We computed the minimum detectable change (MDC) of both measures; using clinician-reported listener effort and a perceptual ratings of severity, we calculated the minimal clinically important difference (MCID) of each measure with respect to both sets of clinical ratings. Results: For articulatory precision, the MDC (.85) was lower than both MCID measures (2.74 and 2.28), and for the ALSFRS-R speech item, MDC (.86) was greater than both MCID measures (.82 and .72), indicating that while the articulatory precision measure detected minimal clinically important differences in speech, the ALSFRS-R speech item did not. Conclusion: The results demonstrate that the digital measure of articulatory precision effectively detects clinically important differences in speech ratings, outperforming the ALSFRS-R speech item. Taken together, the results herein suggest that this speech outcome is a clinically meaningful measure of speech change.

Opinion: more mouse models and more translation needed for ALS

Amyotrophic lateral sclerosis is a complex disorder most of which is 'sporadic' of unknown origin but approximately 10% is familial, arising from single mutations in any of more than 30 genes. Thus, there are more than 30 familial ALS subtypes, with different, often unknown, molecular pathologies leading to a complex constellation of clinical phenotypes. We have mouse models for many genetic forms of the disorder, but these do not, on their own, necessarily show us the key pathological pathways at work in human patients. To date, we have no models for the 90% of ALS that is 'sporadic'. Potential therapies have been developed mainly using a limited set of mouse models, and through lack of alternatives, in the past these have been tested on patients regardless of aetiology. Cancer researchers have undertaken therapy development with similar challenges; they have responded by producing complex mouse models that have transformed understanding of pathological processes, and they have implemented patient stratification in multi-centre trials, leading to the effective translation of basic research findings to the clinic. ALS researchers have successfully adopted this combined approach, and now to increase our understanding of key disease pathologies, and our rate of progress for moving from mouse models to mechanism to ALS therapies we need more, innovative, complex mouse models to address specific questions.

Biofluid Biomarkers in the Prognosis of Amyotrophic Lateral Sclerosis: Recent Developments and Therapeutic Applications

Amyotrophic lateral sclerosis is a neurodegenerative disease characterized by the degeneration of motor neurons for which effective therapies are lacking. One of the most explored areas of research in ALS is the discovery and validation of biomarkers that can be applied to clinical practice and incorporated into the development of innovative therapies. The study of biomarkers requires an adequate theoretical and operational framework, highlighting the "fit-for-purpose" concept and distinguishing different types of biomarkers based on common terminology. In this review, we aim to discuss the current status of fluid-based prognostic and predictive biomarkers in ALS, with particular emphasis on those that are the most promising ones for clinical trial design and routine clinical practice. Neurofilaments in cerebrospinal fluid and blood are the main prognostic and pharmacodynamic biomarkers. Furthermore, several candidates exist covering various pathological aspects of the disease, such as immune, metabolic and muscle damage markers. Urine has been studied less often and should be explored for its possible advantages. New advances in the knowledge of cryptic exons introduce the possibility of discovering new biomarkers. Collaborative efforts, prospective studies and standardized procedures are needed to validate candidate biomarkers. A combined biomarkers panel can provide a more detailed disease status.

Lithium carbonate in amyotrophic lateral sclerosis patients homozygous for the C-allele at SNP rs12608932 in UNC13A: protocol for a confirmatory, randomized, group-sequential, event-driven, double-blind, placebo-controlled trial

BACKGROUND

Given the large genetic heterogeneity in amyotrophic lateral sclerosis (ALS), it seems likely that genetic subgroups may benefit differently from treatment. An exploratory meta-analysis identified that patients homozygous for the C-allele at SNP rs12608932, a single nucleotide polymorphism in the gene UNC13A, had a statistically significant survival benefit when treated with lithium carbonate. We aim to confirm the efficacy of lithium carbonate on the time to death or respiratory insufficiency in patients with ALS homozygous for the C-allele at SNP rs12608932 in UNC13A.

METHODS

A randomized, group-sequential, event-driven, double-blind, placebo-controlled trial will be conducted in 15 sites across Europe and Australia. Patients will be genotyped for UNC13A; those homozygous for the C-allele at SNP rs12608932 will be eligible. Patients must have a diagnosis of ALS according to the revised El Escorial criteria, and a TRICALS risk-profile score between -6.0 and -2.0. An expected number of 1200 patients will be screened in order to enroll a target sample size of 171 patients. Patients will be randomly allocated in a 2:1 ratio to lithium carbonate or matching placebo, and treated for a maximum duration of 24 months. The primary endpoint is the time to death or respiratory insufficiency, whichever occurs first. Key secondary endpoints include functional decline, respiratory function, quality of life, tolerability, and safety. An interim analysis for futility and efficacy will be conducted after the occurrence of 41 events.

DISCUSSION

Lithium carbonate has been proven to be safe and well-tolerated in patients with ALS. Given the favorable safety profile, the potential benefits are considered to outweigh the burden and risks associated with study participation. This study may provide conclusive evidence about the life-prolonging potential of lithium carbonate in a genetic ALS subgroup.

TRIAL REGISTRATION

EudraCT number 2020-000579-19 . Registered on 29 March 2021.

Acute retigabine-induced effects on myelinated motor axons in amyotrophic lateral sclerosis

Altered motor neuron excitability in patients with amyotrophic lateral sclerosis (ALS) has been suggested to be an early pathophysiological mechanism associated with motor neuron death. Compounds that affect membrane excitability may therefore have disease-modifying effects. Through which mechanism(s), these compounds modulate membrane excitability is mostly provided by preclinical studies, yet remains challenging to verify in clinical studies. Here, we investigated how retigabine affects human myelinated motor axons by applying computational modeling to interpret the complex excitability changes in a recent trial involving 18 ALS patients. Compared to baseline, the post-dose excitability differences were modeled well by a hyperpolarizing shift of the half-activation potential of slow potassium (K+ )-channels (till 2 mV). These findings verify that retigabine targets slow K+ -channel gating and highlight the usefulness of computational models. Further developments of this approach may facilitate the identification of early target engagement and ultimately aid selecting responders leading to more personalized treatment strategies.

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.

Short structural variants as informative genetic markers for ALS disease risk and progression

There is considerable variability in disease progression for patients with amyotrophic lateral sclerosis (ALS) including the age of disease onset, site of disease onset, and survival time. There is growing evidence that short structural variations (SSVs) residing in frequently overlooked genomic regions can contribute to complex disease mechanisms and can explain, in part, the phenotypic variability in ALS patients. Here, we discuss SSVs recently characterized by our laboratory and how these discoveries integrate into the current literature on ALS, particularly in the context of application to future clinical trials. These markers may help to identify and differentiate patients for clinical trials that have a similar ALS disease mechanism(s), thereby reducing the impact of participant heterogeneity. As evidence accumulates for the genetic markers discovered in SQSTM1, SCAF4, and STMN2, we hope to improve the outcomes of future ALS clinical trials.

Using the ALSFRS-R in multicentre clinical trials for amyotrophic lateral sclerosis: potential limitations in current standard operating procedures

Objective: Uniform data collection is fundamental for multicentre clinical trials. We aim to determine the variability, between ALS trial centers, in the prevalence of unexpected or implausible improvements in the revised ALS functional rating scale (ALSFRS-R) score, and its associations with individual patient and item characteristics.Methods: We used data from two multicentre studies to estimate the prevalence of an unexpected increase or implausible improvement in the ALSFRS-R score, defined as an increase of 5 points or more between two consecutive, monthly visits. For each patient with a 5-point or more increase, we evaluated the individual contribution of each ALSFRS-R item.Results: Longitudinal ALSFRS-R scores, originating from 114 trial centers enrolling a total of 1,240 patients, were analyzed. A 5-point or more increase in ALSFRS-R total score was found in 151 (12.2%) patients, with prevalence per study center ranging from 0% to 83%. Bulbar onset, faster disease progression at enrollment, and a lower ALSFRS-R score at baseline were associated with a sudden 5-point or more increase in the ALSFRS-R total score. ALSFRS-R items 2 (saliva), 9 (stairs), 10 (dyspnea), and 11 (orthopnea) were the primary drivers when a 5-point or more increase occurred.Conclusions: Sudden 5-point or more increases in ALSFRS-R total scores between two consecutive visits are relatively common. These sudden increases were not found to occur with equal frequency in trial centers; which underscores the need for amending existing standard operating procedures toward a universal version and monitoring of data quality during the study, in multicentre research.

A Descriptive Review of Global Real World Evidence Efforts to Advance Drug Discovery and Clinical Development in Amyotrophic Lateral Sclerosis

Understanding patient clinical progression is a key gateway to planning effective clinical trials and ultimately enabling bringing treatments to patients in need. In a rare disease like amyotrophic lateral sclerosis (ALS), studies of disease natural history critically depend on collaboration between clinical centers, regions, and countries to enable creation of platforms to allow patients, caregivers, clinicians, and researchers to come together and more fully understand the condition. Rare disease registries and collaborative platforms such as those developed in ALS collect real-world data (RWD) in standardized formats, including clinical and biological specimen data used to evaluate risk factors and natural history of disease, treatment patterns and clinical (ClinROs) and patient- reported outcomes (PROs) and validate novel endpoints. Importantly, these data support the development of new therapeutics by supporting the evaluation of feasibility and design of clinical trials and offer valuable information on real-world disease trajectory and outcomes outside of the clinical trial setting for comparative purposes. RWD may help to accelerate therapy development by identifying and validating outcome measures and disease subpopulations. RWD can also make potential contributions to the evaluation of the safety and effectiveness of new indications for approved products and to satisfy post-approval regulatory and market access requirements. There is a lack of amalgamated information on available registries, databases, and other sources of real-world data on ALS; thus, a global review of all available resources was warranted. This targeted review identifies and describes ALS registries, biobanks and collaborative research networks that are collecting and synthesizing RWD for the purposes of increasing patient awareness and advancing scientific knowledge with the hope of expediting future development of new therapies.

Advancing disease monitoring of amyotrophic lateral sclerosis with the compound muscle action potential scan

OBJECTIVE

To determine which compound muscle action potential (CMAP) scan-derived electrophysiological markers are most sensitive for monitoring disease progression in amyotrophic lateral sclerosis (ALS), and whether they hold value for clinical trials.

METHODS

We used four independent patient cohorts to assess longitudinal patterns of a comprehensive set of electrophysiological markers including their association with the ALS functional rating scale (ALSFRS-R). Results were translated to trial sample size requirements.

RESULTS

In 65 patients, 225 thenar CMAP scan recordings were obtained. Electrophysiological markers showed extensive variation in their longitudinal trajectories. Expressed as standard deviations per month, motor unit number estimation (MUNE) values declined by 0.09 (CI 0.07-0.12), D50, a measure that quantifies CMAP scan discontinuities, declined by 0.09 (CI 0.06-0.13) and maximum CMAP by 0.05 (CI 0.03-0.08). ALSFRS-R declined fastest (0.12, CI 0.08 - 0.15), however the between-patient variability was larger compared to electrophysiological markers, resulting in larger sample sizes. MUNE reduced the sample size by 19.1% (n = 388 vs n = 314) for a 6-month study compared to the ALSFRS-R.

CONCLUSIONS

CMAP scan-derived markers show promise in monitoring disease progression in ALS patients, where MUNE may be its most suitable derivate.

SIGNIFICANCE

MUNE may increase clinical trial efficiency compared to clinical endpoints.

MiNDAUS partnership: a roadmap for the cure and management of motor Neurone disease

An innovative approach to patient management, evidence-based policy development, and clinical drug trials is required to provide personalized care and to improve the likelihood of finding an effective treatment for Motor Neurone Disease (MND). The MiNDAus Partnership builds on and extends existing national collaborations in a targeted approach to improve the standard and coordination of care for people living with MND in Australia, and to enhance the prospects of discovering a cure or treatment. Relationships have been developed between leading clinical and research groups as well as patient-centered organizations, care providers, and philanthropy with a shared vision. MiNDAus has established a corporate structure and meets at least biannually to decide on how best to progress research, drug development, and patient management. The key themes are; (i) empowering patients and their family carers to engage in self-management and ensure personalized service provision, treatment, and policy development, (ii) integration of data collection so as to better inform policy development, (iii) unifying patients and carers with advocacy groups, funding bodies, clinicians and academic institutions so as to inform policy development and research, (iv) coordination of research efforts and development of standardized national infrastructure for conducting innovative clinical MND trials that can be harmonized within Australia and with international trials consortia. Such a collaborative approach is required across stakeholders in order to develop innovative management guidelines, underpinned by necessary and evidence-based policy change recommendations, which, will ensure the best patient care until a cure is discovered.

A Road Map for Remote Digital Health Technology for Motor Neuron Disease

Despite recent and potent technological advances, the real-world implementation of remote digital health technology in the care and monitoring of patients with motor neuron disease has not yet been realized. Digital health technology may increase the accessibility to and personalization of care, whereas remote biosensors could optimize the collection of vital clinical parameters, irrespective of patients’ ability to visit the clinic. To facilitate the wide-scale adoption of digital health care technology and to align current initiatives, we outline a road map that will identify clinically relevant digital parameters; mediate the development of benefit-to-burden criteria for innovative technology; and direct the validation, harmonization, and adoption of digital health care technology in real-world settings. We define two key end products of the road map: (1) a set of reliable digital parameters to capture data collected under free-living conditions that reflect patient-centric measures and facilitate clinical decision making and (2) an integrated, open-source system that provides personalized feedback to patients, health care providers, clinical researchers, and caregivers and is linked to a flexible and adaptable platform that integrates patient data in real time. Given the ever-changing care needs of patients and the relentless progression rate of motor neuron disease, the adoption of digital health care technology will significantly benefit the delivery of care and accelerate the development of effective treatments.

Challenging the Established Order: Innovating Clinical Trials for Amyotrophic Lateral Sclerosis

Development of effective treatments for amyotrophic lateral sclerosis (ALS) has been hampered by disease heterogeneity, a limited understanding of underlying pathophysiology, and methodologic design challenges. We have evaluated 2 major themes in the design of pivotal, phase 3 clinical trials for ALS—(1) patient selection and (2) analytical strategy—and discussed potential solutions with the European Medicines Agency. Several design considerations were assessed using data from 5 placebo-controlled clinical trials (n = 988), 4 population-based cohorts (n = 5,100), and 2,436 placebo-allocated patients from the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) database. The validity of each proposed design modification was confirmed by means of simulation and illustrated for a hypothetical setting. Compared to classical trial design, the proposed design modifications reduce the sample size by 30.5% and placebo exposure time by 35.4%. By making use of prognostic survival models, one creates a potential to include a larger proportion of the population and maximize generalizability. We propose a flexible design framework that naturally adapts the trial duration when inaccurate assumptions are made at the design stage, such as enrollment or survival rate. In case of futility, the follow-up time is shortened and patient exposure to ineffective treatments or placebo is minimized. For diseases such as ALS, optimizing the use of resources, widening eligibility criteria, and minimizing exposure to futile treatments and placebo is critical to the development of effective treatments. Our proposed design modifications could circumvent important pitfalls and may serve as a blueprint for future clinical trials in this population.

Novel STMN2 Variant Linked to Amyotrophic Lateral Sclerosis Risk and Clinical Phenotype

Objective

There is a critical need to establish genetic markers that explain the complex phenotypes and pathogenicity of ALS. This study identified a polymorphism in the Stathmin-2 gene and investigated its association with sporadic ALS (sALS) disease risk, age-of onset and survival duration.

Methods

The candidate CA repeat was systematically analyzed using PCR, Sanger sequencing and high throughput capillary separation for genotyping. Stathmin-2 expression was investigated using RT-PCR in patient olfactory neurosphere-derived (ONS) cells and RNA sequencing in laser-captured spinal motor neurons.

Results

In a case-control analysis of a combined North American sALS cohort (n = 321) and population control group (n = 332), long/long CA genotypes were significantly associated with disease risk (p = 0.042), and most strongly when one allele was a 24 CA repeat (p = 0.0023). In addition, longer CA allele length was associated with earlier age-of-onset (p = 0.039), and shorter survival duration in bulbar-onset cases (p = 0.006). In an Australian longitudinal sALS cohort (n = 67), ALS functional rating scale scores were significantly lower in carriers of the long/long genotype (p = 0.034). Stathmin-2 mRNA expression was reduced in sporadic patient ONS cells. Additionally, sALS patients and controls exhibited variable expression of Stathmin-2 mRNA according to CA genotype in laser-captured spinal motor neurons.

Conclusions

We report a novel non-coding CA repeat in Stathmin-2 which is associated with sALS disease risk and has disease modifying effects. The potential value of this variant as a disease marker and tool for cohort enrichment in clinical trials warrants further investigation.

Challenges and opportunities for Multi-National Investigator-Initiated clinical trials for ALS: European and United States collaborations

An inherent challenge to clinical trials that aim to test the efficacy of experimental therapeutics for patients with amyotrophic lateral sclerosis (ALS) is the relative rarity of the disease. A promising solution to this problem is a multi-center approach that ideally includes sites distributed across a broad geographic area. In support of such an approach, the European E-RARE program and the United States National Institutes of Health (NIH) partnered to support the investigator-initiated ROCK-ALS trial (Eudra-CT-Nr.: 2017-003676-31, NCT03792490) as a multi-national collaboration between centers in Europe and North America that is led by European investigators. During the set-up of this international trial, however, a number of unanticipated legal, administrative, and financial complexities emerged that required significant adaptation of the proposed trial scheme. Here, we report our experience navigating these obstacles and describe the potential solutions that we explored. Our experience may inform future efforts to implement multi-national investigator-initiated trials that involve both European and United States centers.