Debamestrocel multimodal effects on biomarker pathways in amyotrophic lateral sclerosis are linked to clinical outcomes

INTRODUCTION/AIMS

Biomarkers have shown promise in amyotrophic lateral sclerosis (ALS) research, but the quest for reliable biomarkers remains active. This study evaluates the effect of debamestrocel on cerebrospinal fluid (CSF) biomarkers, an exploratory endpoint.

METHODS

A total of 196 participants randomly received debamestrocel or placebo. Seven CSF samples were to be collected from all participants. Forty-five biomarkers were analyzed in the overall study and by two subgroups characterized by the ALS Functional Rating Scale-Revised (ALSFRS-R). A prespecified model was employed to predict clinical outcomes leveraging biomarkers and disease characteristics. Causal inference was used to analyze relationships between neurofilament light chain (NfL) and ALSFRS-R.

RESULTS

We observed significant changes with debamestrocel in 64% of the biomarkers studied, spanning pathways implicated in ALS pathology (63% neuroinflammation, 50% neurodegeneration, and 89% neuroprotection). Biomarker changes with debamestrocel show biological activity in trial participants, including those with advanced ALS. CSF biomarkers were predictive of clinical outcomes in debamestrocel-treated participants (baseline NfL, baseline latency-associated peptide/transforming growth factor beta1 [LAP/TGFβ1], change galectin-1, all p < .01), with baseline NfL and LAP/TGFβ1 remaining (p < .05) when disease characteristics (p < .005) were incorporated. Change from baseline to the last measurement showed debamestrocel-driven reductions in NfL were associated with less decline in ALSFRS-R. Debamestrocel significantly reduced NfL from baseline compared with placebo (11% vs. 1.6%, p = .037).

DISCUSSION

Following debamestrocel treatment, many biomarkers showed increases (anti-inflammatory/neuroprotective) or decreases (inflammatory/neurodegenerative) suggesting a possible treatment effect. Neuroinflammatory and neuroprotective biomarkers were predictive of clinical response, suggesting a potential multimodal mechanism of action. These results offer preliminary insights that need to be confirmed.

Identification of gene fusions associated with amyotrophic lateral sclerosis

INTRODUCTION/AIMS

Genetics is an important risk factor for amyotrophic lateral sclerosis (ALS), a neurodegenerative disease affecting motor neurons. Recent findings demonstrate that in addition to specific genetic mutations, structural variants caused by genetic instability can also play a causative role in ALS. Genomic instability can lead to deletions, duplications, insertions, inversions, and translocations in the genome, and these changes can sometimes lead to fusion of distinct genes into a single transcript. Gene fusion events have been studied extensively in cancer; however, they have not been thoroughly investigated in ALS. The aim of this study was to determine whether gene fusions are present in ALS.

METHODS

Gene fusions were identified using STAR Fusion v1.10.0 software in bulk RNA-Seq data from human postmortem samples from publicly available data sets from Target ALS and the New York Genome Center ALS Consortium.

RESULTS

We report the presence of gene fusion events in several brain regions as well as in spinal cord samples in ALS. Although most gene fusions were intra-chromosomal events between neighboring genes and present in both ALS and control samples, there was a significantly greater number of unique gene fusions in ALS compared to controls. Lastly, we identified specific gene fusions with a significant burden in ALS, that were absent from both control samples and known cancer gene fusion databases.

DISCUSSION

Collectively, our findings reveal an enrichment of gene fusions in ALS and suggest that these events may be an additional genetic cause linked to ALS pathogenesis.

Longitudinal comparison of the self-administered ALSFRS-RSE and ALSFRS-R as functional outcome measures in ALS

Objective: Test the feasibility, adherence rates and optimal frequency of digital, remote assessments using the ALSFRS-RSE via a customized smartphone-based app. Methods: This fully remote, longitudinal study was conducted over a 24-week period, with virtual visits every 3 months and weekly digital assessments. 19 ALS participants completed digital assessments via smartphone, including a digital version of the ALSFRS-RSE and mood survey. Interclass correlation coefficients (ICC) and Bland-Altman plots were used to assess agreement between staff-administered and self-reported ALSFRS-R pairs. Longitudinal change was evaluated using ANCOVA models and linear mixed models, including impact of mood and time of day. Impact of frequency of administration of the ALSFRS-RSE on precision of the estimate slope was tested using a mixed effects model. Results: In our ALS cohort, digital assessments were well-accepted and adherence was robust, with completion rates of 86%. There was excellent agreement between the digital self-entry and staff-administered scores computing multiple ICCs (ICC range = 0.925-0.961), with scores on the ALSFRS-RSE slightly higher (1.304 points). Digital assessments were associated with increased precision of the slope, resulting in higher standardized response mean estimates for higher frequencies, though benefit appeared to diminish at biweekly and weekly frequency. Effects of participant mood and time of day on total ALSFRS-RSE score were evaluated but were minimal and not statistically significant. Conclusion: Remote collection of digital patient-reported outcomes of functional status such as the ALSFRS-RSE yield more accurate estimates of change over time and provide a broader understanding of the lived experience of people with ALS.

Upper limb movements as digital biomarkers in people with ALS

BACKGROUND

Objective evaluation of people with amyotrophic lateral sclerosis (PALS) in free-living settings is challenging. The introduction of portable digital devices, such as wearables and smartphones, may improve quantifying disease progression and hasten therapeutic development. However, there is a need for tools to characterize upper limb movements in neurologic disease and disability.

METHODS

Twenty PALS wore a wearable accelerometer, ActiGraph Insight Watch, on their wrist for six months. They also used Beiwe, a smartphone application that collected self-entry ALS Functional Rating Scale-Revised (ALSFRS-RSE) survey responses every 1-4 weeks. We developed several measures that quantify count and duration of upper limb movements: flexion, extension, supination, and pronation. New measures were compared against ALSFRS-RSE total score (Q1-12), and individual responses to specific questions related to handwriting (Q4), cutting food (Q5), dressing and performing hygiene (Q6), and turning in bed and adjusting bed clothes (Q7). Additional analysis considered adjusting for total activity counts (TAC).

FINDINGS

At baseline, PALS with higher Q1-12 performed more upper limb movements, and these movements were faster compared to individuals with more advanced disease. Most upper limb movement metrics had statistically significant change over time, indicating declining function either by decreasing count metrics or by increasing duration metric. All count and duration metrics were significantly associated with Q1-12, flexion and extension counts were significantly associated with Q6 and Q7, supination and pronation counts were also associated with Q4. All duration metrics were associated with Q6 and Q7. All duration metrics retained their statistical significance after adjusting for TAC.

INTERPRETATION

Wearable accelerometer data can be used to generate digital biomarkers on upper limb movements and facilitate patient monitoring in free-living environments. The presented method offers interpretable monitoring of patients' functioning and versatile tracking of disease progression in the limb of interest.

FUNDING

Mitsubishi-Tanabe Pharma Holdings America, Inc.

A fluid biomarker reveals loss of TDP-43 splicing repression in presymptomatic ALS-FTD

Although loss of TAR DNA-binding protein 43 kDa (TDP-43) splicing repression is well documented in postmortem tissues of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), whether this abnormality occurs during early-stage disease remains unresolved. Cryptic exon inclusion reflects loss of function of TDP-43, and thus detection of proteins containing cryptic exon-encoded neoepitopes in cerebrospinal fluid (CSF) or blood could reveal the earliest stages of TDP-43 dysregulation in patients. Here we use a newly characterized monoclonal antibody specific to a TDP-43-dependent cryptic epitope (encoded by the cryptic exon found in HDGFL2) to show that loss of TDP-43 splicing repression occurs in ALS-FTD, including in presymptomatic C9orf72 mutation carriers. Cryptic hepatoma-derived growth factor-like protein 2 (HDGFL2) accumulates in CSF at significantly higher levels in familial ALS-FTD and sporadic ALS compared with controls and is elevated earlier than neurofilament light and phosphorylated neurofilament heavy chain protein levels in familial disease. Cryptic HDGFL2 can also be detected in blood of individuals with ALS-FTD, including in presymptomatic C9orf72 mutation carriers, and accumulates at levels highly correlated with those in CSF. Our findings indicate that loss of TDP-43 cryptic splicing repression occurs early in disease progression, even presymptomatically, and that detection of the HDGFL2 cryptic neoepitope serves as a potential diagnostic biomarker for ALS, which should facilitate patient recruitment and measurement of target engagement in clinical trials.

Identifying amyotrophic lateral sclerosis through interactions with an internet search engine

INTRODUCTION/AIMS

Amyotrophic lateral sclerosis (ALS), a motor neuron disease, remains a clinical diagnosis with an average time from onset of symptoms to diagnosis of about 1 year. Herein we examine the possibility that interactions with an internet search engine can identify people with ALS.

METHODS

We identified 285 anonymous Bing users whose queries indicated that they had been diagnosed with ALS and matched them to: (1) 3276 control users; and (2) 1814 users whose searches indicated they had ALS disease mimics. We tested whether the ALS group could be distinguished from controls and disease mimics based on search engine query data. Finally, we conducted a prospective validation from participants who provided access to their Bing search data.

RESULTS

The model distinguished between the ALS group and controls with an area under the curve (AUC) of 0.81. Model scores for the ALS group differed from the disease mimics group (rank sum test, p < .05 with Bonferroni correction). Mild cognitive impairment could not be distinguished from ALS (p > .05). In the prospective analysis, the model reached an AUC of 0.74.

DISCUSSION

Our results suggest that interactions with search engines should be further studied to understand the potential to act as a tool to assist in screening for ALS and to reduce diagnostic delay.

Targeting amyotrophic lateral sclerosis by neutralizing seeding-competent TDP-43 in CSF

In amyotrophic lateral sclerosis, a disease driven by abnormal transactive response DNA-binding protein of 43 kDa aggregation, CSF may contain pathological species of transactive response DNA-binding protein of 43 kDa contributing to the propagation of pathology and neuronal toxicity. These species, released in part by degenerating neurons, would act as a template for the aggregation of physiological protein contributing to the spread of pathology in the brain and spinal cord. In this study, a robust seed amplification assay was established to assess the presence of seeding-competent transactive response DNA-binding protein of 43 kDa species in CSF of apparently sporadic amyotrophic lateral sclerosis patients. These samples resulted in a significant acceleration of substrate aggregation differentiating the kinetics from healthy controls. In parallel, a second assay was developed to determine the level of target engagement that would be necessary to neutralize such species in human CSF by a therapeutic monoclonal antibody targeting transactive response DNA-binding protein of 43 kDa. For this, evaluation of the pharmacokinetic/pharmacodynamic effect for the monoclonal antibody, ACI-5891.9, in vivo and in vitro confirmed that a CSF concentration of ≍1100 ng/mL would be sufficient for sustained target saturation. Using this concentration in the seed amplification assay, ACI-5891.9 was able to neutralize the transactive response DNA-binding protein of 43 kDa pathogenic seeds derived from amyotrophic lateral sclerosis patient CSF. This translational work adds to the evidence of transmission of transactive response DNA-binding protein of 43 kDa pathology via CSF that could contribute to the non-contiguous pattern of clinical manifestations observed in amyotrophic lateral sclerosis and demonstrates the ability of a therapeutic monoclonal antibody to neutralize the toxic, extracellular seeding-competent transactive response DNA-binding protein of 43 kDa species in the CSF of apparently sporadic amyotrophic lateral sclerosis patients.

Efficacy and Safety of Ravulizumab, a Complement C5 Inhibitor, in Adults With Amyotrophic Lateral Sclerosis: A Randomized Clinical Trial

Importance

Additional therapies for amyotrophic lateral sclerosis (ALS) are urgently needed. Immune-mediated complement activation may be involved in ALS pathogenesis as evidenced by the upregulation of terminal components; thus, complement inhibition could potentially slow progression.

Objective

To evaluate the safety and efficacy of the terminal complement C5 inhibitor ravulizumab in adults with ALS.

Design, Setting, and Participants

This double-blind, placebo-controlled, parallel-group, multinational, randomized, phase 3 clinical trial was conducted from March 30, 2020, to October 17, 2021, in 81 ALS specialty centers across 17 countries. A preplanned, unmasked, nonbinding interim futility analysis was conducted when 33% of participants had completed week 26, wherein a conditional power of less than 10% would halt the trial. A total of 478 individuals were screened, and 96 were excluded. Inclusion criteria were weight of 40 kg or more, fulfillment of the El Escorial diagnostic criteria, and a minimal prestudy Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) progression score of -0.3 points per month.

Interventions

Study treatment consisted of placebo or a weight-based dose of intravenous ravulizumab every 8 weeks until week 42. Participants could continue standard-of-care treatment.

Main Outcomes and Measures

The primary end point was change from baseline in ALSFRS-R score at week 50 based on the Combined Assessment of Function and Survival (CAFS).

Results

A total of 382 participants were randomly assigned 2:1 to receive ravulizumab (n = 255; mean [SD] age, 58.6 [10.6] years; 94 female [36.9%] and 161 male [63.1%]) or placebo (n = 127; mean [SD] age, 58.0 [11.0] years; 58 female [45.7%] and 69 male [54.3%]). The interim analysis showed that the observed mean change from baseline in ALSFRS-R at week 50 was -14.67 points (SE, 0.89 points; 95% CI, -16.42 to -12.91 points) for ravulizumab and -13.33 points (SE, 1.22 points; 95% CI, -15.72 to -10.93 points) for placebo, with no significant difference between the groups (mean [SE] difference, -1.34 [1.46] points; 95% CI, -4.21 to 1.53 points). Based on these data, the trial was terminated for futility. The primary analysis at week 50 showed no significant difference in CAFS between groups (mean [SE], 5.5 [10.8] points; 95% CI, -15.7 to 26.6 points; P = .61). Overall incidence rates for treatment-emergent adverse events were similar for ravulizumab (204 participants [80.0%]) and placebo (108 participants [85.0%]).

Conclusions and Relevance

This trial rapidly showed that terminal complement C5 inhibition with ravulizumab did not slow functional decline in participants with ALS and that the safety profiles of ravulizumab and placebo were similar. Highly effective, novel treatments are critically needed to slow functional decline and extend survival in patients with ALS.

Trial Registration

ClinicalTrials.gov Identifier: NCT04248465.

A roadmap for early psychosocial support in palliative care for people impacted by ALS-reducing suffering, building resiliency, and setting the stage for delivering timely transdiagnostic psychosocial care

This commentary describes the current state of psychosocial care for people with amyotrophic lateral sclerosis and their caregivers. We provide recommendations for developing a roadmap for future research based on existing literature and our group's clinical and research experience to inform next steps to expand evidence-based psychosocial care for people with amyotrophic lateral sclerosis and their caregivers, with potential implications for a range of advanced illnesses.

Design and Statistical Innovations in a Platform Trial for Amyotrophic Lateral Sclerosis

Platform trials allow efficient evaluation of multiple interventions for a specific disease. The HEALEY ALS Platform Trial is testing multiple investigational products in parallel and sequentially in persons with amyotrophic lateral sclerosis (ALS) with the goal of rapidly identifying novel treatments to slow disease progression. Platform trials have considerable operational and statistical efficiencies compared with typical randomized controlled trials due to their use of shared infrastructure and shared control data. We describe the statistical approaches required to achieve the objectives of a platform trial in the context of ALS. This includes following regulatory guidance for the disease area of interest and accounting for potential differences in outcomes of participants within the shared control (potentially due to differences in time of randomization, mode of administration, and eligibility criteria). Within the HEALEY ALS Platform Trial, the complex statistical objectives are met using a Bayesian shared parameter analysis of function and survival. This analysis serves to provide a common integrated estimate of treatment benefit, overall slowing in disease progression, as measured by function and survival while accounting for potential differences in the shared control group using Bayesian hierarchical modeling. Clinical trial simulation is used to provide a better understanding of this novel analysis method and complex design. ANN NEUROL 2023;94:547-560.

Comparing Amyotrophic lateral sclerosis (ALS) patient characteristics from the National ALS Registry and the Massachusetts ALS Registry, data through 2015

OBJECTIVE

To compare, for completeness, ALS patients identified in the National ALS Registry (National Registry) from MA to those in the Massachusetts ALS Registry (MA Registry) through 2015.

METHODS

Sensitivity analyses were conducted to determine the completeness among patients reported in both registries. Patients were matched on first and last name, month and year of birth, sex, as well as Soundex name matching. Demographics for matching and nonmatching ALS patients were also examined using bivariate analyses and logistic regression.

RESULTS

There were 1,042 ALS patients in the MA Registry, and 642 patients matched (61.6%) in the National Registry. Sensitivity analyses found the National Registry had a sensitivity of 87.7% and specificity of 60%. For these matched patients, 522 (81.2%) came from Medicare. Of the 400 patients in the MA Registry not matched to the National Registry, 11.1% were nonwhite, compared to 6.0% in the matched group) (p = 0.0091) and 59.2% were diagnosed before age 60, compared to 28.6% in the matched group (p < 0.0001). Multivariate logistic regression analysis showed being an ALS case (p < 0.0001) and having an ALS diagnosis at age 60 or later (p < 0.0001) were associated with being more likely to match between the two registries.

CONCLUSIONS

These findings show that ALS's non-notifiable condition status at the national level continues to pose a challenge in identifying all ALS patients. This analysis also showed missing cases at the state level even with a reporting statute. Additional strategies are needed for better patient-ascertainment to quantify all ALS patients in the U.S.

Resilient together-ALS: leveraging the NDD transdiagnostic framework to develop an early dyadic intervention for people with amyotrophic lateral sclerosis and their informal care-partners

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive weakness and eventual death, usually within 3-5 years. An ALS diagnosis is associated with substantial emotional distress for both the affected person and their family care-partners which impairs the ability to engage in important conversations about long term care planning, negatively impacts ALS symptoms for the patient, and quality of life for both patient and care-partner. Here we 1) discuss published works identified by the authors about psychosocial interventions for the ALS population, 2) identify a lack of early, dyadic interventions to support psychosocial needs of people with ALS and care-partners; 3) describe the Neurodegenerative Diseases (NDD) framework for early dyadic intervention development and 4) propose an adaptation of an evidence-based early dyadic psychosocial intervention, Recovering Together, for the unique needs of people with ALS and their care-partners (Resilient Together-ALS; RT-ALS) using the NDD framework. Future work will use stakeholder feedback to optimize the intervention for subsequent efficacy testing.

Expanded access protocol (EAP) program for access to investigational products for amyotrophic lateral sclerosis (ALS)

INTRODUCTION/AIMS

Expanded access protocols (EAPs) are a Food and Drug Administration (FDA)-regulated pathway for granting access to investigational products (IPs) to individuals with serious diseases who are ineligible for clinical trials. There is limited information about the use of EAPs in ALS; the aim of this report is to share the design, operational features, and costs of an EAP program for ALS.

METHODS

The program was launched in 2018 at a single center. In alignment with FDA guidance, protocols were designed as individual (single participant) or intermediate size. Inclusion criteria were broad (e.g., no restrictions due to long disease duration or low vital capacity). Safety information was collected in all EAPs. Selected biomarkers were collected in nine of the EAPs.

RESULTS

From July 2018 through February 2022, 17 EAPs were submitted for FDA and institutional review board (IRB) approval. The mean time from submission to approval from the FDA and IRB were 24 days and 37 days, respectively. A total of 164 participants were enrolled and, of these, 77 participants were still receiving IP as of February 2022. The mean duration of participation in an EAP was 12.6 months. No drug-related serious adverse events were reported from any of the EAPs. Average site cost was $613.47 per participant per month, not including IP costs.

CONCLUSION

EAPs provide a framework through which access to IP can be safely provided to people with ALS who do not qualify for clinical trials. Site resources are needed to launch and maintain these programs. This article is protected by copyright. All rights reserved.

Acoustic Measures of Dysphonia in Amyotrophic Lateral Sclerosis

PURPOSE

Identifying efficacious measures to characterize dysphonia in complex neurodegenerative diseases is key to optimal assessment and intervention. This study evaluates the validity and sensitivity of acoustic features of phonatory disruption in amyotrophic lateral sclerosis (ALS).

METHOD

Forty-nine individuals with ALS (40-79 years old) were audio-recorded while producing a sustained vowel and continuous speech. Perturbation/noise-based (jitter, shimmer, and harmonics-to-noise ratio) and cepstral/spectral (cepstral peak prominence, low-high spectral ratio, and related features) acoustic measures were extracted. The criterion validity of each measure was assessed using correlations with perceptual voice ratings provided by three speech-language pathologists. Diagnostic accuracy of the acoustic features was evaluated using area-under-the-curve analysis.

RESULTS

Perturbation/noise-based and cepstral/spectral features extracted from /a/ were significantly correlated with listener ratings of roughness, breathiness, strain, and overall dysphonia. Fewer and smaller correlations between cepstral/spectral measures and perceptual ratings were observed for the continuous speech task, although post hoc analyses revealed stronger correlations in speakers with less perceptually impaired speech. Area-under-the-curve analyses revealed that multiple acoustic features, particularly from the sustained vowel task, adequately differentiated between individuals with ALS with and without perceptually dysphonic voices.

CONCLUSIONS

Our findings support using both perturbation/noise-based and cepstral/spectral measures of sustained /a/ to assess phonatory quality in ALS. Results from the continuous speech task suggest that multisubsystem involvement impacts cepstral/spectral analyses in complex motor speech disorders such as ALS. Further investigation of the validity and sensitivity of cepstral/spectral measures during continuous speech in ALS is warranted.

Randomized trial of inosine for urate elevation in amyotrophic lateral sclerosis

INTRODUCTION/AIMS

Higher urate levels are associated with improved ALS survival in retrospective studies, however whether raising urate levels confers a survival advantage is unknown. In the Safety of Urate Elevation in Amyotrophic Lateral Sclerosis (SURE-ALS) trial, inosine raised serum urate and was safe and well-tolerated. The SURE-ALS2 trial was designed to assess longer term safety. Functional outcomes and a smartphone application were also explored.

METHODS

Participants were randomized 2:1 to inosine (n = 14) or placebo (n = 9) for 20 weeks, titrated to serum urate of 7-8 mg/dL. Primary outcomes were safety and tolerability. Functional outcomes were measured with the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALSFRS-R). Mobility and ALSFRS-R were also assessed by a smartphone application.

RESULTS

During inosine treatment, mean urate ranged 5.68-6.82 mg/dL. Treatment-emergent adverse event (TEAE) incidence was similar between groups (p > .10). Renal TEAEs occurred in three (21%) and hypertension in one (7%) of participants randomized to inosine. Inosine was tolerated in 71% of participants versus placebo 67%. Two participants (14%) in the inosine group experienced TEAEs deemed related to treatment (nephrolithiasis); one was a severe adverse event. Mean ALSFRS-R decline did not differ between groups (p = .69). Change in measured home time was similar between groups. Digital and in-clinic ALSFRS-R correlated well.

DISCUSSION

Inosine met pre-specified criteria for safety and tolerability. A functional benefit was not demonstrated in this trial designed for safety and tolerability. Findings suggested potential utility for a smartphone application in ALS clinical and research settings.

Epidemiology and economic burden of amyotrophic lateral sclerosis in the United States: a literature review

Objective: This review sought to gain a comprehensive, up-to-date understanding of the epidemiology and cost and healthcare resource use (HCRU) burden of amyotrophic lateral sclerosis (ALS) in the US, at a patient and national level. Methods: A targeted literature review (TLR) to identify epidemiological evidence (prevalence, incidence, mortality, survival), and systematic literature review (SLR) to identify cost and HCRU data published since January 2016, were performed. MEDLINE databases and Embase searches were conducted in January 2021. Key congresses (2019-2020) and bibliographies of relevant SLRs were hand-searched. Two high-quality SLRs were reviewed for additional cost data published between January 2001-2015. Registry and database studies were prioritized for epidemiological evidence. To allow comparison between studies in this publication, only evidence from the US was considered, with costs inflated to the 2020/2021 cost-year and converted to US dollars. Results: Eight studies from the epidemiology TLR, and eighteen from the cost and HCRU SLR, were extracted. Reported ALS incidence in the US was ∼1.5 per 100,000 person-years, and point prevalence ranged from 3.84-5.56 per 100,000 population. Total US national costs spanned ∼$212 million-∼$1.4 billion USD/year, and variably consisted of direct costs associated with HCRU and indirect costs. Conclusions: The national cost of ∼$1.02 billion USD/year (estimated using a prevalence of 16,055 cases) best aligns with prevalence estimates found in the TLR (equating to ∼13,000-18,000 cases). However, large-scale, population-based studies are necessary to precisely assess US epidemiology of ALS and capture all costs needed to inform cost-effectiveness models and resource planning.

A fluid biomarker reveals loss of TDP-43 splicing repression in pre-symptomatic ALS

Loss of TAR DNA-binding protein 43 kDa (TDP-43) splicing repression is well-documented in postmortem tissues of amyotrophic lateral sclerosis (ALS), yet whether this abnormality occurs during early-stage disease remains unresolved. Cryptic exon inclusion reflects functional loss of TDP-43, and thus detection of cryptic exon-encoded peptides in cerebrospinal fluid (CSF) could reveal the earliest stages of TDP-43 dysregulation in patients. Here, we use a newly characterized monoclonal antibody specific to a TDP-43-dependent cryptic epitope (encoded by the cryptic exon found in HDGFL2) to show that loss of TDP-43 splicing repression occurs in C9ORF72-associated ALS, including pre-symptomatic mutation carriers. In contrast to neurofilament light and heavy chain proteins, cryptic HDGFL2 accumulates in CSF at higher levels during early stages of disease. Our findings indicate that loss of TDP-43 splicing repression occurs early in disease progression, even pre-symptomatically, and that detection of HDGFL2's cryptic neoepitope may serve as a prognostic test for ALS which should facilitate patient recruitment and measurement of target engagement in clinical trials.

Face and content validation of the amyotrophic lateral sclerosis-Bulbar dysfunction index (ALS-BDI)

Purpose

Early detection and tracking of bulbar dysfunction in amyotrophic lateral sclerosis (ALS) are critical for directing management of the disease. Existing physiological assessments of bulbar dysfunction are often inaccessible and cost-prohibitive for clinical application. Existing clinical assessments are limited. The overall goal of our research is to develop a brief and reliable, clinician-administered assessment tool, the ALS Bulbar Dysfunction Index (ALS-BDI) to evaluate bulbar dysfunction. The aim of this study was to establish content and face validity of the ALS-BDI through item generation and reduction, including item scoring.

Methods

The design of the ALS-BDI followed guidelines outlined by the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). The design stage of the ALS-BDI involved two steps: (Step 1) the generation of candidate items from a literature review of commonly used clinical tools, and selection of items following a review of item reliability and item relevance and expert consensus; (Step 2) the assessment of their content and face validity via online survey feedback from experts (n = 35). The initial design was followed by a semi-structured cognitive interview with Speech-Language Pathologists (n = 5) to finalize a testable draft of the instrument.

Results

Two drafts of the ALS-BDI were developed. The first draft contained 48 items, after a review of existing clinical tools for their relevance to bulbar dysfunction in ALS. Of the 48 items, 35 items were retained after surveying experts and clinician users for their relevance, feasibility, interpretability, and appropriateness. The second draft of the ALS-BDI contained 37 items, due to one item splitting, based on users cognitive interviews.

Conclusions

The ALS-BDI described in this study aims to provide a brief and reliable, clinician-administered assessment tool to evaluate bulbar dysfunction in patients with ALS. Future research will evaluate the psychometric properties of this tool including its reliability, validity, and responsiveness to change over time.

The efficacy of acoustic-based articulatory phenotyping for characterizing and classifying four divergent neurodegenerative diseases using sequential motion rates

Despite the impacts of neurodegeneration on speech function, little is known about how to comprehensively characterize the resulting speech abnormalities using a set of objective measures. Quantitative phenotyping of speech motor impairments may have important implications for identifying clinical syndromes and their underlying etiologies, monitoring disease progression over time, and improving treatment efficacy. The goal of this research was to investigate the validity and classification accuracy of comprehensive acoustic-based articulatory phenotypes in speakers with distinct neurodegenerative diseases. Articulatory phenotypes were characterized based on acoustic features that were selected to represent five components of motor performance: Coordination, Consistency, Speed, Precision, and Rate. The phenotypes were first used to characterize the articulatory abnormalities across four progressive neurologic diseases known to have divergent speech motor deficits: amyotrophic lateral sclerosis (ALS), progressive ataxia (PA), Parkinson's disease (PD), and the nonfluent variant of primary progressive aphasia and progressive apraxia of speech (nfPPA + PAOS). We then examined the efficacy of articulatory phenotyping for disease classification. Acoustic analyses were conducted on audio recordings of 217 participants (i.e., 46 ALS, 52 PA, 60 PD, 20 nfPPA + PAOS, and 39 controls) during a sequential speech task. Results revealed evidence of distinct articulatory phenotypes for the four clinical groups and that the phenotypes demonstrated strong classification accuracy for all groups except ALS. Our results highlight the phenotypic variability present across neurodegenerative diseases, which, in turn, may inform (1) the differential diagnosis of neurological diseases and (2) the development of sensitive outcome measures for monitoring disease progression or assessing treatment efficacy.

Amyotrophic Lateral Sclerosis Clinical Trials and Interpretation of Functional End Points and Fluid Biomarkers: A Review

Importance

Clinical trial activity in amyotrophic lateral sclerosis (ALS) is dramatically increasing; as a result, trial modifications have been introduced to improve efficiency, outcome measures have been reassessed, and considerable discussion about the level of data necessary to advance a drug to approval has occurred. This review discusses what recent pivotal studies can teach the community about these topics.

Observations

By restricting inclusion and exclusion criteria, recent trials have enrolled populations distinct from previous studies. This has led to efficacy signals being observed in studies that are smaller and shorter than was thought feasible previously. However, such trials raise questions about generalizability of results. Small trials with equivocal clinical results also raise questions about the data necessary to lead to regulatory approval. The ALS Functional Rating Scale-Revised remains the most commonly used primary outcome measure; this review discusses innovations in its use. Blood neurofilament levels can predict prognosis in ALS and may be a sensitive indicator of biologic effect; current knowledge does not yet support its use as a primary outcome.

Conclusions and Relevance

It is now possible to use specific inclusion criteria to recruit a homogeneous patient population progressing at a specific rate; this will likely impact trials in the future. Generalizability of results on limited populations remains a concern. Although clinical outcomes remain the most appropriate primary outcome measures, fluid markers reflecting biologically important processes will assume more importance as more is learned about the association between such markers and clinical end points. The benefit of use of analytic strategies, such as responder analyses, is still uncertain.

Combined Regulatory T-Lymphocyte and IL-2 Treatment Is Safe, Tolerable, and Biologically Active for 1 Year in Persons With Amyotrophic Lateral Sclerosis

Background and Objectives

In a phase 1 amyotrophic lateral sclerosis (ALS) study, autologous infusions of expanded regulatory T-lymphocytes (Tregs) combined with subcutaneous interleukin (IL)-2 were safe and well tolerated. Treg suppressive function increased and disease progression stabilized during the study. The present study was conducted to confirm the reliability of these results.

Methods

Participants with ALS underwent leukapheresis, and their Tregs were isolated and expanded in a current Good Manufacturing Practice facility. Seven participants were randomly assigned in a 1:1 ratio to receive Treg infusions (1 × 10⁶ cells/kg) IV every 4 weeks and IL-2 (2 × 10⁵ IU/m²) injections 3 times/wk or matching placebo in a 24-week randomized controlled trial (RCT). Six participants proceeded into a 24-week dose-escalation open-label extension (OLE). Two additional participants entered directly into the OLE. The OLE included dose escalation of Treg infusions to 2 × 10⁶ cells/kg and 3 × 10⁶ cells/kg at 4-week intervals.

Results

The Treg/IL-2 treatments were safe and well tolerated, and Treg suppressive function was higher in the active group of the RCT. A meaningful evaluation of progression rates in the RCT between the placebo and active groups was not possible due to the limited number of enrolled participants aggravated by the COVID-19 pandemic. In the 24-week OLE, the Treg/IL-2 treatments were also safe and well tolerated in 8 participants who completed the escalating doses. Treg suppressive function and numbers were increased compared with baseline. Six of 8 participants changed by an average of −2.7 points per the ALS Functional Rating Scale–Revised, whereas the other 2 changed by an average of −10.5 points. Elevated levels of 2 markers of peripheral inflammation (IL-17C and IL-17F) and 2 markers of oxidative stress (oxidized low-density lipoprotein receptor 1 and oxidized LDL) were present in the 2 rapidly progressing participants but not in the slower progressing group.

Discussion

Treg/IL-2 treatments were safe and well tolerated in the RCT and OLE with higher Treg suppressive function. During the OLE, 6 of 8 participants showed slow to no progression. The 2 of 8 rapid progressors had elevated markers of oxidative stress and inflammation, which may help delineate responsiveness to therapy. Whether Treg/IL-2 treatments can slow disease progression requires a larger clinical study (ClinicalTrials.gov number, NCT04055623).

Classification of Evidence

This study provides Class IV evidence that Treg infusions and IL-2 injections are safe and effective for patients with ALS.

Antibody Response to HML-2 May Be Protective in Amyotrophic Lateral Sclerosis

OBJECTIVES

Reactivation of HERV-K(HML-2) has been found in subsets of individuals with amyotrophic lateral sclerosis (ALS). This study examines the antibody response against HML-2 in ALS and analyzes its clinical relevance.

METHODS

Antibodies to HML-2 envelope (env) were analyzed using a peptide array for epitope mapping and by a peptide enzyme-linked immunosorbent assay (ELISA) in 242 healthy donors, and 243 ALS and 85 multiple sclerosis (MS) individuals. Extracellular levels of HML-2 were analyzed by digital polymerase chain reaction (PCR).

RESULTS

Antibodies in the sera of ALS individuals recognized more HML-2 env peptides compared to healthy controls (p < 0.0001). ALS individuals had higher levels of HML-2 than healthy donors (p = 0.02) and higher antibody levels against a select HML-2 env peptide compared to healthy donors or individuals with multiple sclerosis (p < 0.0001). 55.14% of ALS compared to 21.16% of healthy donors and 13.10% of MS individuals had antibodies against the HML-2 peptide (AUC = 0.769, p < 0.0001). Levels of extracellular HML-2 DNA in serum (p = 0.02) and the number of HML-2 env peptides recognized by ALS sera (p = 0.02) correlated with disease duration. Among ALS individuals, lower levels of HML-2 antibodies were associated with a definite diagnosis per EL Escorial criteria (p = 0.03), and with a lower predicted (p = 0.02) and observed survival (p = 0.03).

INTERPRETATION

There is a differential antibody response against specific epitopes of HML-2 env in ALS and controls, suggesting epitope spreading, likely due to persistent antigenic exposure following reactivation of the viral genes. Low levels of antibodies to HML-2 env in ALS are associated with poor prognosis and decreased survival probability. ANN NEUROL 2022;92:782-792.

A revision to the United States national ALS registry's algorithm to improve Case-Ascertainment

Objective: To evaluate the impact of 1) updating the existing algorithm to improve case-finding sensitivity and 2) reclassifying the Registry's diagnostic status nomenclature into four new categories ("confirmed ALS," "likely ALS," "undetermined ALS," or "not ALS") versus the current three ("definite ALS," "possible ALS," or "not ALS") to be more inclusive and descriptive of cases and individuals. Methods: A retrospective analysis of Registry data from 2011-2017 was conducted to follow "possible ALS" individuals over time to determine what qualifier caused them to convert, if at all and when, to Registry-eligible cases (i.e. "confirmed ALS" or "likely ALS"). Results: In 2011, 720 individuals were classified by the Registry algorithm as having "possible ALS". By 2017, 42% of these had converted to Registry-eligible ALS cases. Approximately 14% of those who were identified solely based on an ALS prescription drug never converted to Registry-eligible cases. This analysis indicates that "possible ALS" individuals with a single prescription for an ALS drug should be converted to Registry-eligible cases which would add between 300-500 cases per year on average. Conclusions: The Registry's existing algorithm likely results in the under-ascertainment of ALS cases. However, updating the algorithm with the inclusion of patients having been prescribed ALS-specific drugs, even with a single prescription, leads to improved epidemiologic estimates of ALS in the US. This and future algorithmic updates will help the Registry more accurately depict the true disease burden of ALS in the US.

Longitudinal comparison of the self-entry Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-RSE) and Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) as outcome measures in people with amyotrophic lateral sclerosis

INTRODUCTION/AIMS

Improved functional outcome measures in amyotrophic lateral sclerosis (ALS) would aid ALS trial design and help hasten drug discovery. We evaluate the longitudinal performance of the Rasch-Built Overall Amyotrophic Lateral Sclerosis Disability Scale (ROADS) compared to the Amyotrophic Lateral Sclerosis Functional Rating Scale Revised for Self-Entry (ALSFRS-RSE) as patient reported outcomes of functional status in people with ALS.

METHODS

Participants completed the ROADS and the ALSFRS-RSE questionnaires at baseline, 3-, 6-, and 12- mo using Research Electronic Data Capture as part of a prospective, longitudinal, remote, online survey study of fatigue in ALS from 9/2020 to 12/2021. The scales were compared cross-sectionally (at baseline) and longitudinally. Correlation coefficients, coefficients of variation, and descriptive statistics were assessed.

RESULTS

A total of 182 adults with ALS consented to the study. This volunteer sample was comprised of predominantly White, non-Hispanic, non-smoking participants. Consented participant survey completion was approximately 90% at baseline and greater than 40% at 12 mo. The ALSFRS-RSE and the ROADS had high, significant agreement at 3 and 6 mo by Cohen's kappa ≥71% (p < 0.001); the number of functional increases or plateaus on the two scales were not significantly different; and the coefficient of variation of functional decline was similar at the 6-month mark, though higher for the ROADS at 3 mo and lower at 12 mo.

DISCUSSION

Although the ROADS performed similarly to the ALSFRS-RSE in an observational cohort, it has psychometric advantages, such as Rasch-modeling and unidimensionality. It merits further investigation as a patient reported outcome of overall disability and efficacy outcome measure in ALS trials.

Intravenous edaravone treatment in ALS and survival: An exploratory, retrospective, administrative claims analysis

BACKGROUND

We aimed to evaluate overall survival in US patients with amyotrophic lateral sclerosis (ALS) treated with intravenous (IV) edaravone compared with those not treated with IV edaravone in a real-world setting.

METHODS

This exploratory retrospective comparative effectiveness observational analysis included patients with ALS who were enrolled in an administrative claims database from 8 August 2017 to 31 March 2020. Propensity score matching identified IV edaravone-treated patients (cases) and non-edaravone-treated patients (controls) matched for covariates: age, race, geographic region, sex, pre-index disease duration, insurance, history of cardiovascular disease, riluzole prescription, gastrostomy tube placement, artificial nutrition, noninvasive ventilation, and all-cause hospitalisation. For cases, the index date was the date of the first claim for IV edaravone. For controls, it was the date IV edaravone was available (8 August 2017). The effect of IV edaravone on all-cause mortality was estimated with shared frailty Cox regression analysis.

FINDINGS

318 cases were matched to 318 controls. In both groups, 208 patients (65.4%) had a history of riluzole prescription. As of 31 March 2021, there were 155 deaths (48.7%) among the cases and 196 among the controls (61.6%). Median overall survival time was 29.5 months with edaravone and 23.5 months without, respectively, and the risk of death was 27% lower in cases than in controls (HR, 0.73; 95% CI, 0.59-0.91; p=0.005).

INTERPRETATION

In this real-world analysis, IV edaravone treatment in a large predominantly riluzole-treated US cohort was associated with prolonged overall survival compared with not using IV edaravone. Data from adequately powered RCTs are needed to support this finding.

FUNDING

Funded by Mitsubishi Tanabe Pharma America.

An expanded access protocol of RT001 in amyotrophic lateral sclerosis-Initial experience with a lipid peroxidation inhibitor

INTRODUCTION/AIMS

Lipid peroxidation is thought to play a biologically important role in motor neuron death in amyotrophic lateral sclerosis (ALS). 11,11 Di-deuterated linoleic ethyl ester (RT001) prevents lipid peroxidation in cellular and mitochondrial membranes. Herein we report on the use of RT001 under expanded access (EA).

METHODS

We provided RT001 to patients with ALS via EA at a single site. The starting dose was 2.88 g/day, which was increased to to 8.64 g/day as tolerated. Participants were not eligible for alternative clinical trials. Participants were followed for adverse events and pharmacokinetic (PK) parameters were measured approximately 3 months after RT001 initiation.

RESULTS

Sixteen participants received RT001 (5.6 ± 1.6 g/day; dose range, 1.92 to 8.64 g/day) for a mean period of 10.8 ± 7.1 months. After 3 months of treatment, PK studies showed that RT001 was absorbed, metabolized, and incorporated into red blood cell membranes at concentrations expected to be therapeutic based on in vitro models. The most common adverse events were gastrointestinal, including diarrhea, which occurred in 25% of the participants, and were considered possibly related to RT001. One participant (6%) discontinued due to an adverse event. Ten serious adverse events occurred: these events were recognized complications of ALS and none were attributed to treatment with RT001.

DISCUSSION

RT001 was administered safely to a small group of people living with ALS in the context of an EA protocol. Currently, there is an ongoing randomized, double-blind, controlled study of RT001 in ALS.

Combination of ciprofloxacin/celecoxib as a novel therapeutic strategy for ALS

OBJECTIVE

This study aimed to evaluate the safety and tolerability of a fixed-dose co-formulation of ciprofloxacin and celecoxib (PrimeC) in patients with amyotrophic lateral sclerosis (ALS), and to examine its effects on disease progression and ALS-related biomarkers.

METHODS

In this proof of concept, open-label, phase IIa study of PrimeC in 15 patients with ALS, participants were administered PrimeC thrice daily for 12 months. The primary endpoints were safety and tolerability. Exploratory endpoints included disease progression outcomes such as forced vital capacity, revised ALS functional rating scale, and effect on algorithm-predicted survival. In addition, indications of a biological effect were assessed by selected biomarker analyses, including TDP-43 and LC3 levels in neuron-derived exosomes (NDEs), and serum neurofilaments.

RESULTS

Four participants experienced adverse events (AEs) related to the study drug. None of these AEs were unexpected, and most were mild or moderate (69%). Additionally, no serious AEs were related to the study drug. One participant tested positive for COVID-19 and recovered without complications, and no other abnormal laboratory investigations were found. Participants' survival compared to their predictions showed no safety concerns. Biomarker analyses demonstrated significant changes associated with PrimeC in neural-derived exosomal TDP-43 levels and levels of LC3, a key autophagy marker.

INTERPRETATION

This study supports the safety and tolerability of PrimeC in ALS. Biomarker analyses suggest early evidence of a biological effect. A placebo-controlled trial is required to disentangle the biomarker results from natural progression and to evaluate the efficacy of PrimeC for the treatment of ALS. Summary for social media if publishedTwitter handles: @NeurosenseT, @ShiranZimri•What is the current knowledge on the topic? ALS is a severe neurodegenerative disease, causing death within 2-5 years from diagnosis. To date there is no effective treatment to halt or significantly delay disease progression.•What question did this study address? This study assessed the safety, tolerability and exploratory efficacy of PrimeC, a fixed dose co-formulation of ciprofloxacin and celecoxib in the ALS population.•What does this study add to our knowledge? This study supports the safety and tolerability of PrimeC in ALS, and exploratory biomarker analyses suggest early insight for disease related-alteration.•How might this potentially impact the practice of neurology? These results set the stage for a larger, placebo-controlled study to examine the efficacy of PrimeC, with the potential to become a new drug candidate for ALS.

Pharmacotherapy for Amyotrophic Lateral Sclerosis: A Review of Approved and Upcoming Agents

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder involving loss of upper and lower motor neurons, with most cases ending in death within 3-5 years of onset. Several molecular and cellular pathways have been identified to cause ALS; however, treatments to stop or reverse disease progression are yet to be found. Riluzole, a neuroprotective agent offering only a modest survival benefit, has long been the sole disease-modifying therapy for ALS. Edaravone, which demonstrated statistically significant slowing of ALS disease progression, is gaining approval in an increasing number of countries since its first approval in 2015. Sodium phenylbutyrate and taurursodiol (PB-TURSO) was conditionally approved in Canada in 2022, having shown significant slowing of disease progression and prolonged survival. Most clinical trials have focused on testing small molecules affecting common cellular pathways in ALS: targeting glutamatergic, apoptotic, inflammatory, and oxidative stress mechanisms among others. More recently, clinical trials utilizing stem cell transplantation and other biologics have emerged. This rich and ever-growing pipeline of investigational products, along with innovative clinical trial designs, collaborative trial networks, and an engaged ALS community', provide renewed hope to finding a cure for ALS. This article reviews existing ALS therapies and the current clinical drug development pipeline.

Identifying patterns in amyotrophic lateral sclerosis progression from sparse longitudinal data

The clinical presentation of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease, varies widely across patients, making it challenging to determine if potential therapeutics slow progression. We sought to determine whether there were common patterns of disease progression that could aid in the design and analysis of clinical trials. We developed an approach based on a mixture of Gaussian processes to identify clusters of patients sharing similar disease progression patterns, modeling their average trajectories and the variability in each cluster. We show that ALS progression is frequently nonlinear, with periods of stable disease preceded or followed by rapid decline. We also show that our approach can be extended to Alzheimer's and Parkinson's diseases. Our results advance the characterization of disease progression of ALS and provide a flexible modeling approach that can be applied to other progressive diseases.

Validity of Off-the-Shelf Automatic Speech Recognition for Assessing Speech Intelligibility and Speech Severity in Speakers With Amyotrophic Lateral Sclerosis

PURPOSE

There is increasing interest in using automatic speech recognition (ASR) systems to evaluate impairment severity or speech intelligibility in speakers with dysarthria. We assessed the clinical validity of one currently available off-the-shelf (OTS) ASR system (i.e., a Google Cloud ASR API) for indexing sentence-level speech intelligibility and impairment severity in individuals with amyotrophic lateral sclerosis (ALS), and we provided guidance for potential users of such systems in research and clinic.

METHOD

Using speech samples collected from 52 individuals with ALS and 20 healthy control speakers, we compared word recognition rate (WRR) from the commercially available Google Cloud ASR API (Machine WRR) to clinician-provided judgments of impairment severity, as well as sentence intelligibility (Human WRR). We assessed the internal reliability of Machine and Human WRR by comparing the standard deviation of WRR across sentences to the minimally detectable change (MDC), a clinical benchmark that indicates whether results are within measurement error. We also evaluated Machine and Human WRR diagnostic accuracy for classifying speakers into clinically established categories.

RESULTS

Human WRR achieved better accuracy than Machine WRR when indexing speech severity, and, although related, Human and Machine WRR were not strongly correlated. When the speech signal was mixed with noise (noise-augmented ASR) to reduce a ceiling effect, Machine WRR performance improved. Internal reliability metrics were worse for Machine than Human WRR, particularly for typical and mildly impaired severity groups, although sentence length significantly impacted both Machine and Human WRRs.

CONCLUSIONS

Results indicated that the OTS ASR system was inadequate for early detection of speech impairment and grading overall speech severity. While Machine and Human WRR were correlated, ASR should not be used as a one-to-one proxy for transcription speech intelligibility or clinician severity ratings. Overall, findings suggested that the tested OTS ASR system, Google Cloud ASR, has limited utility for grading clinical speech impairment in speakers with ALS.

Effect of sodium phenylbutyrate/taurursodiol on tracheostomy/ventilation-free survival and hospitalisation in amyotrophic lateral sclerosis: long-term results from the CENTAUR trial

BACKGROUND

Coformulated sodium phenylbutyrate/taurursodiol (PB/TURSO) was shown to prolong survival and slow functional decline in amyotrophic lateral sclerosis (ALS).

OBJECTIVE

Determine whether PB/TURSO prolonged tracheostomy/ventilation-free survival and/or reduced first hospitalisation in participants with ALS in the CENTAUR trial.

METHODS

Adults with El Escorial Definite ALS ≤18 months from symptom onset were randomised to PB/ TURSO or placebo for 6 months. Those completing randomised treatment could enrol in an open-label extension (OLE) phase and receive PB/TURSO for ≤30 months. Times to the following individual or combined key events were compared in the originally randomised treatment groups over a period spanning trial start through July 2020 (longest postrandomisation follow-up, 35 months): death, tracheostomy, permanent assisted ventilation (PAV) and first hospitalisation.

RESULTS

Risk of any key event was 47% lower in those originally randomised to PB/TURSO (n=87) versus placebo (n=48, 71% of whom received delayed-start PB/TURSO in the OLE phase) (HR=0.53; 95% CI 0.35 to 0.81; p=0.003). Risks of death or tracheostomy/PAV (HR=0.51; 95% CI 0.32 to 0.84; p=0.007) and first hospitalisation (HR=0.56; 95% CI 0.34 to 0.95; p=0.03) were also decreased in those originally randomised to PB/TURSO.

CONCLUSIONS

Early PB/TURSO prolonged tracheostomy/PAV-free survival and delayed first hospitalisation in ALS.

TRIAL REGISTRATION NUMBER

NCT03127514; NCT03488524.

Protocol for psychometric evaluation of the Amyotrophic Lateral Sclerosis - Bulbar Dysfunction Index (ALS-BDI): a prospective longitudinal study

INTRODUCTION

Early detection and tracking of bulbar dysfunction in amyotrophic lateral sclerosis (ALS) are critical for directing management of the disease. Current clinical bulbar assessment tools are lacking, while existing physiological instrumental assessments are often inaccessible and cost-prohibitive for clinical application. The goal of our research is to develop and validate a brief and reliable, clinician-administered assessment tool-the ALS-Bulbar Dysfunction Index (ALS-BDI). This publication describes the study protocol that has been established to ascertain the tools' psychometric properties.

METHODS AND ANALYSIS

The ALD-BDI's development closely follows guidelines outlined by the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). Through the proposed study protocol, we expect to establish psychometric properties of both individual test items of the ALS-BDI as well as the final version of the entire tool, including test-retest and inter-rater reliability, construct validity using gold-standard assessment methods and responsiveness.

ETHICS AND DISSEMINATION

This study has been reviewed and approved by research ethics boards at two data collection sites: Sunnybrook Health Science Centre, primary (Toronto, Canada; ID3080) and Mass General Brigham (#2013P001746, Boston, USA). Prior to participation in the study, the participants sign the informed consent in accordance with the Declaration of Helsinki. Once validated, the ALS-BDI will be disseminated to key stakeholders. Following validation, the ALS-BDI and any required training material will be implemented for clinical use in a context of a multidisciplinary ALS clinic and used as an outcome measure for clinical trials in ALS research.

Excessive release of inorganic phosphate by ALS/FTD astrocytes causes non-cell-autonomous toxicity to motoneurons

Non-cell-autonomous mechanisms contribute to neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), in which astrocytes release unidentified factors that are toxic to motoneurons (MNs). We report here that mouse and patient iPSC-derived astrocytes with diverse ALS/FTD-linked mutations (SOD1, TARDBP, and C9ORF72) display elevated levels of intracellular inorganic polyphosphate (polyP), a ubiquitous, negatively charged biopolymer. PolyP levels are also increased in astrocyte-conditioned media (ACM) from ALS/FTD astrocytes. ACM-mediated MN death is prevented by degrading or neutralizing polyP in ALS/FTD astrocytes or ACM. Studies further reveal that postmortem familial and sporadic ALS spinal cord sections display enriched polyP staining signals and that ALS cerebrospinal fluid (CSF) exhibits increased polyP concentrations. Our in vitro results establish excessive astrocyte-derived polyP as a critical factor in non-cell-autonomous MN degeneration and a potential therapeutic target for ALS/FTD. The CSF data indicate that polyP might serve as a new biomarker for ALS/FTD.

Using Smartphones to Reduce Research Burden in a Neurodegenerative Population and Assessing Participant Adherence: A Randomized Clinical Trial and Two Observational Studies

Background

Smartphone studies provide an opportunity to collect frequent data at a low burden on participants. Therefore, smartphones may enable data collection from people with progressive neurodegenerative diseases such as amyotrophic lateral sclerosis at high frequencies for a long duration. However, the progressive decline in patients’ cognitive and functional abilities could also hamper the feasibility of collecting patient-reported outcomes, audio recordings, and location data in the long term.

Objective

The aim of this study is to investigate the completeness of survey data, audio recordings, and passively collected location data from 3 smartphone-based studies of people with amyotrophic lateral sclerosis.

Methods

We analyzed data completeness in three studies: 2 observational cohort studies (study 1: N=22; duration=12 weeks and study 2: N=49; duration=52 weeks) and 1 clinical trial (study 3: N=49; duration=20 weeks). In these studies, participants were asked to complete weekly surveys; weekly audio recordings; and in the background, the app collected sensor data, including location data. For each of the three studies and each of the three data streams, we estimated time-to-discontinuation using the Kaplan–Meier method. We identified predictors of app discontinuation using Cox proportional hazards regression analysis. We quantified data completeness for both early dropouts and participants who remained engaged for longer.

Results

Time-to-discontinuation was shortest in the year-long observational study and longest in the clinical trial. After 3 months in the study, most participants still completed surveys and audio recordings: 77% (17/22) in study 1, 59% (29/49) in study 2, and 96% (22/23) in study 3. After 3 months, passively collected location data were collected for 95% (21/22), 86% (42/49), and 100% (23/23) of the participants. The Cox regression did not provide evidence that demographic characteristics or disease severity at baseline were associated with attrition, although it was somewhat underpowered. The mean data completeness was the highest for passively collected location data. For most participants, data completeness declined over time; mean data completeness was typically lower in the month before participants dropped out. Moreover, data completeness was lower for people who dropped out in the first study month (very few data points) compared with participants who adhered long term (data completeness fluctuating around 75%).

Conclusions

These three studies successfully collected smartphone data longitudinally from a neurodegenerative population. Despite patients’ progressive physical and cognitive decline, time-to-discontinuation was higher than in typical smartphone studies. Our study provides an important benchmark for participant engagement in a neurodegenerative population. To increase data completeness, collecting passive data (such as location data) and identifying participants who are likely to adhere during the initial phase of a study can be useful.

Trial Registration

ClinicalTrials.gov NCT03168711; https://clinicaltrials.gov/ct2/show/NCT03168711

Phase 2B randomized controlled trial of NP001 in amyotrophic lateral sclerosis: pre‐specified and post‐hoc analyses

Introduction/Aims

ALS is a heterogeneous disease that may be complicated or in part driven by inflammation. NP001, a regulator of macrophage activation, was associated with slowing disease progression in those with higher levels of the plasma inflammatory marker C‐reactive protein (CRP) in phase 2A studies in ALS. Here, we evaluate the effects of NP001 in a phase 2B trial, and perform a post hoc analysis with combined data from the preceding phase 2A trial.

Methods

The phase 2B trial enrolled 138 participants within 3 y of symptom onset and with plasma hs‐CRP values >1.13 mg/L. They were randomized 1:1 to receive either placebo or NP001 for 6 mo. Change from baseline ALSFRS‐R scores was the primary efficacy endpoint. Secondary endpoints included vital capacity (VC) change from baseline and percentage of participants showing no decline of ALSFRS‐R score over 6 mo (non‐progressor).

Results

The phase 2B study did not show significant differences between placebo and active treatment with respect to change in ALSFRS‐R scores, or VC. The drug was safe and well tolerated. A post hoc analysis identified a 40‐ to 65‐y‐old subset in which NP001‐treated patients demonstrated slower declines in ALSFRS‐R score by 36% and VC loss by 51% compared with placebo. A greater number of non‐progressors were NP001‐treated compared with placebo (p = .004).

Discussion

Although the phase 2B trial failed to meet its primary endpoints, post hoc analyses identified a subgroup whose decline in ALSFRS‐R and VC scores were significantly slower than placebo. Further studies will be required to validate these findings.

A Phase 1 study of GDC-0134, a dual leucine zipper kinase inhibitor, in ALS

Objective

Dual leucine zipper kinase (DLK), which regulates the c‐Jun N‐terminal kinase pathway involved in axon degeneration and apoptosis following neuronal injury, is a potential therapeutic target in amyotrophic lateral sclerosis (ALS). This first‐in‐human study investigated safety, tolerability, and pharmacokinetics (PK) of oral GDC‐0134, a small‐molecule DLK inhibitor. Plasma neurofilament light chain (NFL) levels were explored in GDC‐0134‐treated ALS patients and DLK conditional knockout (cKO) mice.

Methods

The study included placebo‐controlled, single and multiple ascending‐dose (SAD; MAD) stages, and an open‐label safety expansion (OLE) with adaptive dosing for up to 48 weeks.

Results

Forty‐nine patients were enrolled. GDC‐0134 (up to 1200 mg daily) was well tolerated in the SAD and MAD stages, with no serious adverse events (SAEs). In the OLE, three study drug‐related SAEs occurred: thrombocytopenia, dysesthesia (both Grade 3), and optic ischemic neuropathy (Grade 4); Grade ≤2 sensory neurological AEs led to dose reductions/discontinuations. GDC‐0134 exposure was dose‐proportional (median half‐life = 84 h). Patients showed GDC‐0134 exposure‐dependent plasma NFL elevations; DLK cKO mice also exhibited plasma NFL compared to wild‐type littermates.

Interpretation

This trial characterized GDC‐0134 safety and PK, but no adequately tolerated dose was identified. NFL elevations in GDC‐0134‐treated patients and DLK cKO mice raised questions about interpretation of biomarkers affected by both disease and on‐target drug effects. The safety profile of GDC‐0134 was considered unacceptable and led to discontinuation of further drug development for ALS. Further work is necessary to understand relationships between neuroprotective and potentially therapeutic effects of DLK knockout/inhibition and NFL changes in patients with ALS.

Adaptive Platform Trials to Transform ALS Therapy Development

Current therapeutic development in ALS relies on individual randomized clinical trials to test a specific investigational product in a single patient population. This approach has intrinsic limitations including cost, time, and lack of flexibility. Adaptive platform trials represent a novel approach to investigate several interventions for a single disease in a continuous manner. Already in use in oncology, this approach is now being employed more often in neurology. Here, we describe a newly launched, platform trial for amyotrophic lateral sclerosis (ALS). The HEALEY ALS Platform Trial is testing multiple investigational products concurrently in people with ALS, with the goal of rapidly identifying novel treatments, biomarkers, and trial endpoints. This article is protected by copyright. All rights reserved.

"You Say Severe, I Say Mild": Toward an Empirical Classification of Dysarthria Severity

PURPOSE

The main purpose of this study was to create an empirical classification system for speech severity in patients with dysarthria secondary to amyotrophic lateral sclerosis (ALS) by exploring the reliability and validity of speech-language pathologists' (SLPs') ratings of dysarthric speech.

METHOD

Ten SLPs listened to speech samples from 52 speakers with ALS and 20 healthy control speakers. SLPs were asked to rate the speech severity of the speakers using five response options: normal, mild, moderate, severe, and profound. Four severity-surrogate measures were also calculated: SLPs transcribed the speech samples for the calculation of speech intelligibility and rated the effort it took to understand the speakers on a visual analog scale. In addition, speaking rate and intelligible speaking rate were calculated for each speaker. Intrarater and interrater reliability were calculated for each measure. We explored the validity of clinician-based severity ratings by comparing them to the severity-surrogate measures. Receiver operating characteristic (ROC) curves were conducted to create optimal cutoff points for defining dysarthria severity categories.

RESULTS

Intrarater and interrater reliability for the clinician-based severity ratings were excellent and were comparable to reliability for the severity-surrogate measures explored. Clinician severity ratings were strongly associated with all severity-surrogate measures, suggesting strong construct validity. We also provided a range of values for each severity-surrogate measure within each severity category based on the cutoff points obtained from the ROC analyses.

CONCLUSIONS

Clinician severity ratings of dysarthric speech are reliable and valid. We discuss the underlying challenges that arise when selecting a stratification measure and offer recommendations for a classification scheme when stratifying patients and research participants into speech severity categories.

Co-Occurrence of Hypernasality and Voice Impairment in Amyotrophic Lateral Sclerosis: Acoustic Quantification

PURPOSE

Hypernasality and atypical voice characteristics are common features of dysarthric speech due to amyotrophic lateral sclerosis (ALS). Existing acoustic measures have been developed to primarily target either hypernasality or voice impairment, and the effects of co-occurring hypernasality-voice problems on these measures are unknown. This report explores (a) the extent to which acoustic measures are affected by concurrent perceptually identified hypernasality and voice impairment due to ALS and (b) candidate acoustic measures of early indicators of hypernasality and voice impairment in the presence of multisystem involvement in individuals with ALS.

METHOD

Two expert listeners rated severity of hypernasality and voice impairment in sentences produced by individuals with ALS (n = 27). The samples were stratified based on perceptual ratings: voice/hypernasality asymptomatic, predominantly hypernasal, predominantly voice impairment, and mixed (co-occurring hypernasality and voice impairment). Groups were compared using established acoustic measures of hypernasality (one-third octave analysis) and voice (cepstral/spectral analysis) impairment.

RESULTS

The one-third octave analysis differentiated all groups; the cepstral peak prominence differentiated all groups except asymptomatic versus mixed, whereas the low-to-high spectral ratio did not differ among groups. Additionally, one-third octave analyses demonstrated promising speech diagnostic potential.

CONCLUSIONS

The results highlight the need to consider the validity of measures in the context of multisubsystem involvement. Our preliminary findings further suggest that the one-third octave analysis may be an optimal approach to quantify hypernasality and voice abnormalities in the presence of multisystem speech impairment. Future evaluation of the diagnostic accuracy of the one-third octave analysis is warranted.

A Randomized Placebo-Controlled Phase 3 Study of Mesenchymal stem cells induced to secrete high levels of neurotrophic factors in Amyotrophic Lateral Sclerosis

Introduction/Aims

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative illness with great unmet patient need. We aimed to evaluate whether mesenchymal stem cells induced to secrete high levels of neurotrophic factors (MSC‐NTF), a novel autologous cell‐therapy capable of targeting multiple pathways, could safely slow ALS disease progression.

Methods

This randomized, double‐blind, placebo‐controlled study enrolled ALS participants meeting revised El Escorial criteria, revised ALS Functional Rating Scale (ALSFRS‐R) ≥25 (screening) and ≥3 ALSFRS‐R points decline prior to randomization. Participants received three treatments of MSC‐NTF or placebo intrathecally. The primary endpoint evaluated efficacy of MSC‐NTF through a responder analysis and safety. A change in disease progression post‐treatment of ≥1.25 points/mo defines a clinical response. A pre‐specified analysis leveraged baseline ALSFRS‐R of 35 as a subgroup threshold.

Results

Overall, MSC‐NTF treatment was well tolerated; there were no safety concerns. Thirty‐three percent of MSC‐NTF and 28% of placebo participants met clinical response criteria at 28 wk (odds ratio [OR] = 1.33, P = .45); thus, the primary endpoint was not met. A pre‐specified analysis of participants with baseline ALSFRS‐R ≥ 35 (n = 58) showed a clinical response rate at 28 wk of 35% MSC‐NTF and 16% placebo (OR = 2.6, P = .29). Significant improvements in cerebrospinal biomarkers of neuroinflammation, neurodegeneration, and neurotrophic factor support were observed with MSC‐NTF, with placebo unchanged.

Discussion

The study did not reach statistical significance on the primary endpoint. However, a pre‐specified subgroup suggests that MSC‐NTF participants with less severe disease may have retained more function compared to placebo. Given the unmet patient need, the results of this trial warrant further investigation.

Recruitment of Patients With Amyotrophic Lateral Sclerosis for Clinical Trials and Epidemiological Studies: Descriptive Study of the National ALS Registry's Research Notification Mechanism

BACKGROUND

Researchers face challenges in patient recruitment, especially for rare, fatal diseases such as amyotrophic lateral sclerosis (ALS). These challenges include obtaining sufficient statistical power as well as meeting eligibility requirements such as age, sex, and study proximity. Similarly, persons with ALS (PALS) face difficulty finding and enrolling in research studies for which they are eligible.

OBJECTIVE

The aim of this study was to describe how the federal Agency for Toxic Substances and Disease Registry's (ATSDR) National ALS Registry is linking PALS to scientists who are conducting research, clinical trials, and epidemiological studies.

METHODS

Through the Registry's online research notification mechanism (RNM), PALS can elect to be notified about new research opportunities. This mechanism allows researchers to upload a standardized application outlining their study design and objectives, and proof of Institutional Review Board approval. If the application is approved, ATSDR queries the Registry for PALS meeting the study's specific eligibility criteria, and then distributes the researcher's study material and contact information to PALS via email. PALS then need to contact the researcher directly to take part in any research. Such an approach allows ATSDR to protect the confidentiality of Registry enrollees.

RESULTS

From 2013 to 2019, a total of 46 institutions around the United States and abroad have leveraged this tool and over 600,000 emails have been sent, resulting in over 2000 patients conservatively recruited for clinical trials and epidemiological studies. Patients between the ages of 60 and 69 had the highest level of participation, whereas those between the ages of 18 and 39 and aged over 80 had the lowest. More males participated (4170/7030, 59.32%) than females (2860/7030, 40.68%).

CONCLUSIONS

The National ALS Registry's RNM benefits PALS by connecting them to appropriate ALS research. Simultaneously, the system benefits researchers by expediting recruitment, increasing sample size, and efficiently identifying PALS meeting specific eligibility requirements. As more researchers learn about and use this mechanism, both PALS and researchers can hasten research and expand trial options for PALS.

Novel genetic variants in MAPT and alterations in tau phosphorylation in amyotrophic lateral sclerosis post-mortem motor cortex and cerebrospinal fluid

Although the molecular mechanisms underlying amyotrophic lateral sclerosis (ALS) are not yet fully understood, several studies report alterations in tau phosphorylation in both sporadic and familial ALS. Recently, we have demonstrated that phosphorylated tau at S396 (pTau‐S396) is mislocalized to synapses in ALS motor cortex (mCTX) and contributes to mitochondrial dysfunction. Here, we demonstrate that while there was no overall increase in total tau, pTau‐S396, and pTau‐S404 in ALS post‐mortem mCTX, total tau and pTau‐S396 were increased in C9ORF72‐ALS. Additionally, there was a significant decrease in pTau‐T181 in ALS mCTX compared controls. Furthermore, we leveraged the ALS Knowledge Portal and Project MinE data sets and identified ALS‐specific genetic variants across MAPT, the gene encoding tau. Lastly, assessment of cerebrospinal fluid (CSF) samples revealed a significant increase in total tau levels in bulbar‐onset ALS together with a decrease in CSF pTau‐T181:tau ratio in all ALS samples, as reported previously. While increases in CSF tau levels correlated with a faster disease progression as measured by the revised ALS functional rating scale (ALSFRS‐R), decreases in CSF pTau‐T181:tau ratio correlated with a slower disease progression, suggesting that CSF total tau and pTau‐T181 ratio may serve as biomarkers of disease in ALS. Our findings highlight the potential role of pTau‐T181 in ALS, as decreases in CSF pTau‐T181:tau ratio may reflect the significant decrease in pTau‐T181 in post‐mortem mCTX. Taken together, these results indicate that tau phosphorylation is altered in ALS post‐mortem mCTX as well as in CSF and, importantly, the newly described pathogenic or likely pathogenic variants identified in MAPT in this study are adjacent to T181 and S396 phosphorylation sites further highlighting the potential role of these tau functional domains in ALS.

Although the molecular mechanisms underlying amyotrophic lateral sclerosis (ALS) are not yet fully understood, recent studies report alterations in tau phosphorylation in ALS. Our study builds on these findings and demonstrates that tau phosphorylation is altered in post‐mortem ALS motor cortex and highlights new and ALS‐specific variants in MAPT, the gene encoding tau. Lastly, we report alterations in phosphorylated tau in ALS cerebrospinal fluid that may function as a predictive biomarker for ALS.

Targeting Tau Mitigates Mitochondrial Fragmentation and Oxidative Stress in Amyotrophic Lateral Sclerosis

Understanding the mechanisms underlying amyotrophic lateral sclerosis (ALS) is crucial for the development of new therapies. Previous studies have demonstrated that mitochondrial dysfunction is a key pathogenetic event in ALS. Interestingly, studies in Alzheimer's disease (AD) post-mortem brain and animal models link alterations in mitochondrial function to interactions between hyperphosphorylated tau and dynamin-related protein 1 (DRP1), the GTPase involved in mitochondrial fission. Recent evidence suggest that tau may be involved in ALS pathogenesis, therefore, we sought to determine whether hyperphosphorylated tau may lead to mitochondrial fragmentation and dysfunction in ALS and whether reducing tau may provide a novel therapeutic approach. Our findings demonstrated that pTau-S396 is mis-localized to synapses in post-mortem motor cortex (mCTX) across ALS subtypes. Additionally, the treatment with ALS synaptoneurosomes (SNs), enriched in pTau-S396, increased oxidative stress, induced mitochondrial fragmentation, and altered mitochondrial connectivity without affecting cell survival in vitro. Furthermore, pTau-S396 interacted with DRP1, and similar to pTau-S396, DRP1 accumulated in SNs across ALS subtypes, suggesting increases in mitochondrial fragmentation in ALS. As previously reported, electron microscopy revealed a significant decrease in mitochondria density and length in ALS mCTX. Lastly, reducing tau levels with QC-01-175, a selective tau degrader, prevented ALS SNs-induced mitochondrial fragmentation and oxidative stress in vitro. Collectively, our findings suggest that increases in pTau-S396 may lead to mitochondrial fragmentation and oxidative stress in ALS and decreasing tau may provide a novel strategy to mitigate mitochondrial dysfunction in ALS. pTau-S396 mis-localizes to synapses in ALS. ALS synaptoneurosomes (SNs), enriched in pTau-S396, increase oxidative stress and induce mitochondrial fragmentation in vitro. pTau-S396 interacts with the pro-fission GTPase DRP1 in ALS. Reducing tau with a selective degrader, QC-01-175, mitigates ALS SNs-induced mitochondrial fragmentation and increases in oxidative stress in vitro.

Interplay between immunity and amyotrophic lateral sclerosis: Clinical impact

Amyotrophic lateral sclerosis (ALS) is a debilitating and rapidly fatal neurodegenerative disease. Despite decades of research and many new insights into disease biology over the 150 years since the disease was first described, causative pathogenic mechanisms in ALS remain poorly understood, especially in sporadic cases. Our understanding of the role of the immune system in ALS pathophysiology, however, is rapidly expanding. The aim of this manuscript is to summarize the recent advances regarding the immune system involvement in ALS, with particular attention to clinical translation. We focus on the potential pathophysiologic mechanism of the immune system in ALS, discussing local and systemic factors (blood, cerebrospinal fluid, and microbiota) that influence ALS onset and progression in animal models and people. We also explore the potential of Positron Emission Tomography to detect neuroinflammation in vivo, and discuss ongoing clinical trials of therapies targeting the immune system. With validation in human patients, new evidence in this emerging field will serve to identify novel therapeutic targets and provide realistic hope for personalized treatment strategies.

Plasma neurofilament light predicts mortality in patients with stroke

Given the heterogeneity of stroke brain injury, there is a clear need for a biomarker that determines the degree of neuroaxonal injury across stroke types. We evaluated whether blood neurofilament light (NFL) would fulfill this purpose for patients with acute cerebral infarction (ACI; N = 227), aneurysmal subarachnoid hemorrhage (aSAH; N = 58), or nontraumatic intracerebral hemorrhage (ICH; N = 29). We additionally validated our findings in two independent cohorts of patients with ICH (N = 96 and N = 54) given the scarcity of blood biomarker studies for this deadliest stroke type. Compared to healthy individuals (N = 79 and N = 48 for the discovery and validation cohorts, respectively), NFL was higher for all stroke types. NFL associated with radiographic markers of brain tissue damage. It correlated with the extent of early ischemic injury in patients with ACI, hemorrhage severity in patients with aSAH, and intracranial hemorrhage volume in patients with ICH. In all patients, NFL independently correlated with scores from the NIH Stroke Scale, the modified Rankin Scale, and the Mini-Mental State Examination at blood draw, which respectively assess neurological, functional, and cognitive status. Furthermore, higher NFL concentrations independently associated with 3- or 6-month functional disability and higher all-cause mortality. These data support NFL as a uniform method to estimate neuroaxonal injury and forecast mortality regardless of stroke mechanism. As a prognostic biomarker, blood NFL has the potential to assist with planning supportive and rehabilitation services and improving clinical trial efficiency for stroke therapeutics and devices.

Two Distinct Clinical Phenotypes of Bulbar Motor Impairment in Amyotrophic Lateral Sclerosis

Objective: Understanding clinical variants of motor neuron diseases such as amyotrophic lateral sclerosis (ALS) is critical for discovering disease mechanisms and across-patient differences in therapeutic response. The current work describes two clinical subgroups of patients with ALS that, despite similar levels of bulbar motor involvement, have disparate clinical and functional speech presentations.

Methods: Participants included 47 healthy control speakers and 126 speakers with ALS. Participants with ALS were stratified into three clinical subgroups (i.e., bulbar asymptomatic, bulbar symptomatic high speech function, and bulbar symptomatic low speech function) based on clinical metrics of bulbar motor impairment. Acoustic and lip kinematic analytics were derived from each participant's recordings of reading samples and a rapid syllable repetition task. Group differences were reported on clinical scales of ALS and bulbar motor severity and on multiple speech measures.

Results: The high and low speech-function subgroups were found to be similar on many of the dependent measures explored. However, these two groups were differentiated on the basis of an acoustic measure used as a proxy for tongue movement.

Conclusion: This study supports the hypothesis that high and low speech-function subgroups do not differ solely in overall severity, but rather, constitute two distinct bulbar motor phenotypes. The findings suggest that the low speech-function group exhibited more global involvement of the bulbar muscles than the high speech-function group that had relatively intact lingual function. This work has implications for clinical measures used to grade bulbar motor involvement, suggesting that a single bulbar measure is inadequate for capturing differences among phenotypes.

Ibudilast (MN-166) in amyotrophic lateral sclerosis- an open label, safety and pharmacodynamic trial

Ibudilast (MN-166) is an inhibitor of macrophage migration inhibitory factor (MIF) and phosphodiesterases 3,4,10 and 11 (Gibson et al., 2006; Cho et al., 2010). Ibudilast attenuates CNS microglial activation and secretion of pro-inflammatory cytokines (Fujimoto et al., 1999; Cho et al., 2010). In vitro evidence suggests that ibudilast is neuroprotective by suppressing neuronal cell death induced by microglial activation. People with ALS have increased microglial activation measured by [11C]PBR28-PET in the motor cortices. The primary objective is to determine the impact of ibudilast on reducing glial activation and neuroaxonal loss in ALS, measured by PBR28-PET and serum Neurofilament light (NfL). The secondary objectives included determining safety and tolerability of ibudilast high dosage (up to 100 mg/day) over 36 weeks. In this open label trial, 35 eligible ALS participants underwent ibudilast treatment up to 100 mg/day for 36 weeks. Of these, 30 participants were enrolled in the main study cohort and were included in biomarker, safety and tolerability analyses. Five additional participants were enrolled in the expanded access arm, who did not meet imaging eligibility criteria and were included in the safety and tolerability analyses. The primary endpoints were median change from baseline in (a) PBR28-PET uptake in primary motor cortices, measured by standard uptake value ratio (SUVR) over 12-24 weeks and (b) serum NfL over 36-40 weeks. The secondary safety and tolerability endpoints were collected through Week 40. The baseline median (range) of PBR28-PET SUVR was 1.033 (0.847, 1.170) and NfL was 60.3 (33.1, 219.3) pg/ml. Participants who completed both pre and post-treatment scans had PBR28-PET SUVR median(range) change from baseline of 0.002 (-0.184, 0.156) , P = 0.5 (n = 22). The median(range) NfL change from baseline was 0.4 pg/ml (-1.8, 17.5), P = 0.2 (n = 10 participants). 30(86%) participants experienced at least one, possibly study drug related adverse event. 13(37%) participants could not tolerate 100 mg/day and underwent dose reduction to 60-80 mg/day and 11(31%) participants discontinued study drug early due to drug related adverse events. The study concludes that following treatment with ibudilast up to 100 mg/day in ALS participants, there were no significant reductions in (a) motor cortical glial activation measured by PBR28-PET SUVR over 12-24 weeks or (b) CNS neuroaxonal loss, measured by serum NfL over 36-40 weeks. Dose reductions and discontinuations due to treatment emergent adverse events were common at this dosage in ALS participants. Future pharmacokinetic and dose-finding studies of ibudilast would help better understand tolerability and target engagement in ALS.

Patient reported outcomes in ALS: characteristics of the self-entry ALS Functional Rating Scale-revised and the Activities-specific Balance Confidence Scale

Objective: This study characterized two patient-reported outcome measures (PROMs): a patient-facing adaptation of the revised amyotrophic lateral sclerosis (ALS) Functional Rating Scale ("self-entry ALSFRS-R") and the Activities-specific Balance Confidence (ABC) Scale. Methods: ALS patients presenting to clinic completed PROMs that included (1) the self-entry ALSFRS-R, (2) the Activities-specific Balance Confidence Scale (ABC Scale), and (3) a question about falls. PROM data were compared to one another and to the traditional ALSFRS-R collected by trained evaluators in clinic ("standard ALSFRS-R"). Results: Over the data collection period, 449 ALS patients completed at least one of the three PROMs. Self-entry vs. standard ALSFRS-R total scores (n = 183) had high agreement (intraclass correlation (ICC)=0.81, 95% CI = 0.67, 0.88). Self-entry ALSFRS-R total scores were significantly higher than standard ALSFRS-R total scores (2.3 points, p < 0.001). In a subset of participants who contributed data at two timepoints, the average ALSFRS-R decline was not significantly different between methods (n = 49). ABC scores correlated highly with self-entry and standard ALSFRS-R Gross Motor subdomain scores (Pearson's r = 0.72, p < 0.001 and Pearson's r = 0.76, p < 0.001, respectively; n = 130). ABC score was negatively correlated with the number of reported falls within the last month (Spearman's r=-0.40; p < 0.001; n = 130). A 10-point decrease in ABC score increased odds of a reported fall by 16%. Conclusions: In a multidisciplinary clinic setting, self-entry and standard ALSFRS-R scores were similar, but not interchangeable. Self-entry scores were higher than standard ALSFRS-R scores but declined at a similar rate to the standard ALSFRS-R. ABC scores correlated with self-reported fall history and thus may provide useful data for clinical care.