A Patient-Centered Evaluation of Meaningful Change on the 32-Item Motor Function Measure in Spinal Muscular Atrophy Using Qualitative and Quantitative Data

Developing Meaningful Score Differences for the Bayley-4 and Vineland-3 in Angelman Syndrome using a Delphi Panel

Objectives

To develop within-patient meaningful score differences (MSDs) on the Bayley Scales of Infant Development, Fourth Edition (Bayley-4), and the Vineland Adaptive Behavior Scales, Third Edition (Vineland-3), for individuals with Angelman syndrome (AS).

Methods

A Delphi method, involving a panel of 19 caregivers of individuals with AS, was used to establish MSDs for Bayley-4 and Vineland-3 Growth Scale Values. MSD was defined as the smallest change that would noticeably impact the daily functioning of an individual with AS or family quality of life in a way that was important to the individual with AS or their family. For each subscale of the Bayley-4 and Vineland-3, the panel was presented with 2 to 4 vignettes describing varying levels of baseline functioning and asked to select a MSD from a range of potential values. An iterative process involving three rounds of ratings and two rounds of discussion was used to build consensus. The median caregiver rating from round 3 was retained as the final recommended MSD value for each vignette.

Results

Final MSD ratings for the five subscales of Bayley-4 and 10 subscales of the Vineland-3 had an agreement rate of 70% or higher. MSD thresholds for each subscale were not single cut-offs, but rather reflected a range of MSD values dependent on level of baseline functioning.

Conclusions

The Delphi Panel method incorporates the caregiver perspective to provide preliminary estimates of what constitutes meaningful within person change on the Bayley-4 and Vineland-3 in individuals with AS with various levels of baseline functioning.

Highlights

⍰ To acquire regulatory approval in drug development, sponsors must demonstrate both statistical significance and clinical meaningfulness of a treatment effect.While several clinical trials are underway in AS, within person meaningful score difference thresholds are not yet established for the most commonly used outcome measures, namely the Bayley and Vineland.⍰ Aligning with FDA guidance, we have developed an innovative qualitative approach using a Delphi panel to incorporate caregiver perspectives in defining meaningful change and generated preliminary patient-informed meaningful score differences (MSDs) for individuals with Angelman Syndrome.⍰ What caregivers of individuals with AS consider to be a MSD on the measures depends primarily on the baseline severity of their child's presentation.

Swallowing function in patients with spinal muscular atrophy before and after the introduction of new gene-based therapies: what has changed?

OBJECTIVE

Individuals diagnosed with Spinal Muscular Atrophy (SMA), particularly those presenting with the most severe phenotypes, have long contended with significant swallowing dysfunction. The recent emergence of efficacious advanced therapy has fundamentally altered the landscape of SMA management. By encompassing both the pre and post gene-based therapy eras within our analysis, we endeavour to elucidate the potential impact of these novel therapeutic interventions on this function.

METHODS

Following the established methodology outlined by the Joanna Briggs Institute, a scoping review was conducted. This review encompassed relevant literature published up to March 2024. Two electronic databases were searched, with additional studies identified by reviewing reference lists of pertinent articles. The search strategy employed a combination of keywords including "spinal muscular atrophy", "SMA", "swallowing", "feeding", and "nutrition". Articles were initially screened based on title and abstract, followed by a full-text review of eligible studies published in peer-reviewed English language journals.

RESULTS

The initial database search resulted in 462 articles, from which 23 studies were ultimately selected for analysis. Pre gene-based therapy studies revealed swallowing dysfunction as a prominent feature. Patients frequently reported challenges with chewing, choking on solids and liquids, and abnormal tongue movements during eating. Early dysphagia research relied on subjective measures (questionnaires, scales). objective measures like video fluoroscopic (VFSS) were rare. After gene-based therapies (GBTs), VFSS became the dominant, more objective method. Studies investigating the post-gene therapy era suggest potential clinical benefits, with trends towards improvement or stabilization of swallowing function.

CONCLUSION

Pre gene-based therapy studies revealed widespread swallowing dysfunction in SMA. Conversely, the post-treatment era suggests potential improvement. Future research should prioritize identifying optimal therapies for individual swallowing function and develop validated assessments to optimize SMA management.

Risdiplam in Adult Patients With 5q Spinal Muscular Atrophy: A Single-Center Longitudinal Study

INTRODUCTION/AIMS

Risdiplam was the first orally administered drug approved to treat spinal muscular atrophy (SMA). Efficacy in adults is based on short-term observational studies. This longitudinal study aimed to examine risdiplam's efficacy and safety in adults over a long period of follow-up.

METHODS

All eligible SMA patients ≥ 16 years old, followed at the Muscular Dystrophy Association Hellas Neuromuscular Diseases Unit between April 2021 and December 2023, were included. We prospectively evaluated motor function, muscle strength, and pulmonary function before and after 6, 12, 18, 24, and 30 months of treatment. Laboratory assessments and patient-reported adverse events were recorded.

RESULTS

Overall, 14 patients (18-57 years, 93% treatment-naive) received risdiplam for a median period of 28.5 months (range 6-30). There were statistically significant improvements in the Hammersmith Functional Motor Scale-Expanded (mean difference [MD] 1.5 [95%CI 0.49-2.42]), Revised Upper Limb Module (MD 1.6 [95%CI 0.54-2.73]), Motor Function Measurement-32 (MD 2.7[95%CI 1.52-3.93]), Medical Research Council scores of the upper (MD 3 [95%CI 0.8-5.2]), and lower (MD 1.7 [95%CI 0.1-3.3]) limbs (all p ≤ 0.05). Eighty-two percent of patients achieved a clinically meaningful improvement (CMI) in at least one scale. Overall, CMI occurred earlier in type 3 patients. SMA functional rating scale and respiratory function tests remained stable over time. Fifty-seven percent of patients did not report any adverse events. None discontinued treatment.

DISCUSSION

Risdiplam treatment over 30 months resulted in overall CMI in most treated adult SMA type 2 or 3 patients. Outpatient drug administration and overall patient management proved feasible and safe. Larger studies are warranted.

Taldefgrobep Alfa and the Phase 3 RESILIENT Trial in Spinal Muscular Atrophy

Spinal muscular atrophy (SMA) is a rare, genetic neurodegenerative disorder caused by insufficient production of survival motor neuron (SMN) protein. Diminished SMN protein levels lead to motor neuron loss, causing muscle atrophy and weakness that impairs daily functioning and reduces quality of life. SMN upregulators offer clinical improvements and increased survival in SMA patients, although significant unmet needs remain. Myostatin, a TGF-β superfamily signaling molecule that binds to the activin II receptor, negatively regulates muscle growth; myostatin inhibition is a promising therapeutic strategy for enhancing muscle. Combining myostatin inhibition with SMN upregulation, a comprehensive therapeutic strategy targeting the whole motor unit, offers promise in SMA. Taldefgrobep alfa is a novel, fully human recombinant protein that selectively binds to myostatin and competitively inhibits other ligands that signal through the activin II receptor. Given a robust scientific and clinical rationale and the favorable safety profile of taldefgrobep in patients with neuromuscular disease, the RESILIENT phase 3, randomized, placebo-controlled trial is investigating taldefgrobep as an adjunct to SMN upregulators in SMA (NCT05337553). This manuscript reviews the role of myostatin in muscle, explores the preclinical and clinical development of taldefgrobep and introduces the phase 3 RESILIENT trial of taldefgrobep in SMA.

Exploring variability in cognitive functioning in patients with spinal muscular atrophy: a scoping review

The cognitive functioning of individuals with spinal muscular atrophy (SMA) is not well understood, prompting a call for more research to better grasp cognitive involvement in SMA. This study aims to explore recent findings regarding cognitive outcomes in SMA patients, including correlations between clinical features and cognitive abilities. The investigation seeks to identify commonly used measures for assessing cognitive function in this patient population. A scoping review following the Joanna Briggs Institute methodology examined literature until December 2023. Two databases were searched along with relevant article references using specific terms such as "spinal muscular atrophy," "SMA," "cognitive," "abilities," "functions," "intellective," or "intellectual." Screening focused on titles and abstracts from English language peer-reviewed journals. After the initial research, 1452 articles were identified. Subsequent screening and selection led to the inclusion of 13 articles in the review. Among these studies, four indicated a cognitive trend within the normal range for SMA patients. In four other studies, the majority of patients fell within the normal range. However, smaller proportions were observed to be either above or below the norm compared to the controls. Three studies reported noted cognitive performance below the average, while two showed above-average scores. The scoping review suggests that most SMA patients have cognitive abilities similar to the general population, with types II and III showing even lesser impact. However, certain cognitive domains may be affected in type I patients, highlighting the need for further research to fully understand cognitive involvement in SMA.

Exploring functional strength changes during nusinersen treatment in symptomatic children with SMA types 2 and 3

The Hammersmith Functional Motor Scale-Expanded (HFMSE) is a validated outcome measure for monitoring changes in functional strength in patients with spinal muscular atrophy (SMA). The objective of this study was to explore changes in HFMSE item-scores in children with SMA types 2 and 3a treated with nusinersen over a period of six to twenty months. We stratified patients according to motor ability (sitting and walking), and calculated numbers and percentages for each specific improvement (positive score change) or decrease (negative score change) for the total group and each subgroup and calculated frequency distributions of specific score changes. Ninety-one percent of the children showed improvement in at least 1 item, twenty-eight percent showed a score decrease in 1 or more items. In the first six to twenty months of nusinersen treatment motor function change was characterized by the acquisition of the ability to perform specific tasks with compensation strategies (score changes from 0 to 1). Children with the ability to sit were most likely to improve in items that assess rolling, whilst children with the ability to walk most likely improved in items that assess half-kneeling. The ability most frequently lost was hip flexion in supine position.

Improvement in functional motor scores in patients with non-ambulatory spinal muscle atrophy during Nusinersen treatment in South Korea: a single center study

We analyzed the changes in various motor function scores over a four-year period in patients with non-ambulatory spinal muscular atrophy (SMA) during Nusinersen treatment. Patients underwent Hammersmith Infant Neurological Examination (HINE) or Hammersmith Functional Motor Scale Expanded (HFMSE) before treatment, and approximately every 4 months thereafter. Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) or Children's Hospital of Philadelphia - Adult Test of Neuromuscular Disorders (CHOP ATEND), Revised Upper Limb Module (RULM), and Motor Function Measure (MFM) were performed based on baseline functional status. Narrative interviews were conducted to explore post-treatment physical improvement regarding activities of daily living (ADLs) and fatigue after ADLs. Based on HFMSE results, 9 patients achieved minimum clinically important differences. Average rates of change (slopes) with corresponding 95% confidence intervals for all assessment tools were in a positive direction. CHOP-INTEND showed the most prominent improvement in children and adolescents followed by HFMSE. Improvements in CHOP-ATEND were most noticeable in adults. Improvements were accompanied by changes in ADLs as observed in the narrative interviews. It is necessary to consider various functional aspects to determine the effectiveness of Nusinersen therapy. The objective assessment of the therapeutic effect of Nusinersen in non-ambulatory SMA requires consideration of functional aspects and the related ADLs.

Patients' Perceptions of Nusinersen Effects According to Their Responder Status

Background and Objective: Patients with spinal muscular atrophy (SMA) treated with a disease-modifying therapy (DMT) are often classified as responders or non-responders based on the attainment of a specific improvement threshold on validated functional scales. This categorization may significantly impact treatment reimbursement in some countries. The aim of this research is to evaluate the perception of treatments and their benefit by patients considered as responders or non-responders. Methods: In this non-commercial multicenter study, 99 post-symptomatically treated SMA type I-III patients with a median age of 11.2 (0.39-57.4) years at treatment initiation were stratified into three groups based on their treatment outcomes, i.e., those exhibiting clinically significant improvement (N = 41), those with non-clinically significant improvement (N = 18), or those showing no improvement (N = 40). Fifteen months after treatment, the initiation patients or patients' caregivers were assessed using a patient-rated scoring system based on the Patient Global Impression of Change (PGIC) scale, comprising 22 questions targeting important aspects and tasks in the daily life of patients with SMA. Results: We found no statistical difference in the patient perception of treatment benefits in 17 out of 22 domains across patient groups. Conclusions: Our results suggest that functional motor scales do not recapitulate patients' and patients' caregivers' experience of the effect of nusinersen treatment in SMA.

Perspectives of patients with advanced or metastatic non-small cell lung cancer on symptoms, impacts on daily activities, and thresholds for meaningful change: a qualitative research study

Introduction

Advanced or metastatic non-small cell lung cancer (NSCLC) is associated with significant symptom burden. It is important to understand the impact of these disease-and treatment-related symptoms on patients' daily lives and explore from a patient perspective what constitutes a meaningful change in NSCLC symptoms.

Methods

Patient experience of advanced or metastatic NSCLC was explored in this prospective, non-interventional qualitative research study recruiting patients from the United States (US). Interviews were conducted to explore the most important symptoms, daily life impacts, and patients' perspectives of what constitutes meaningful change when considering their current symptoms versus 6-12 months prior, based on the Patient Global Impression of Severity (PGI-S) and Patient Global Impression of Change (PGI-C) items.

Results

Between February and April 2022, 19 US-based patients with Stage IV NSCLC were recruited; 95% were female, 63% were White, 79% had been diagnosed >1 year prior, and 63% were receiving targeted therapy. Over half the patients indicated their most important symptoms were fatigue, shortness of breath, and cough. Patient differentiation between whether symptoms were disease- or treatment-related lacked concordance, and often patients were unable to distinguish the two. The most frequently mentioned impacts of these symptoms on patients' daily lives were difficulty walking, sleep disturbance, anxiety/depression, impact on relationships, and difficulty doing daily tasks. Most patients considered a one-point change on the PGI-S or PGI-C to be meaningful based on rating their symptom severity at the time of the interview compared with 6-12 months before the interview.

Conclusion

Based on their own symptom experience, patients with advanced or metastatic NSCLC indicated a one-point threshold for meaningful change, whether improvement or worsening. This suggests a one-point change on the PGI-S or PGI-C may be a potential anchor for patient-reported outcome (PRO) endpoints used in clinical trials. It is important to use PRO instruments that capture the symptoms and impacts identified as most important to patients. These findings highlight the importance of using qualitative methods to assess disease-related symptoms, treatment-related side effects, and the impacts on daily life for patients with advanced or metastatic NSCLC, underscoring how qualitative assessments can complement quantitative PRO instruments for evaluating clinical trials.

Two-year efficacy and safety of risdiplam in patients with type 2 or non-ambulant type 3 spinal muscular atrophy (SMA)

Risdiplam is an oral, survival of motor neuron 2 (SMN2) pre-mRNA splicing modifier approved for the treatment of spinal muscular atrophy (SMA). SUNFISH (NCT02908685) Part 2, a Phase 3, randomized, double-blind, placebo-controlled study, investigated the efficacy and safety of risdiplam in type 2 and non‑ambulant type 3 SMA. The primary endpoint was met: a significantly greater change from baseline in 32-item Motor Function Measure (MFM32) total score was observed with risdiplam compared with placebo at month 12. After 12 months, all participants received risdiplam while preserving initial treatment blinding. We report 24-month efficacy and safety results in this population. Month 24 exploratory endpoints included change from baseline in MFM32 and safety. MFM‑derived results were compared with an external comparator. At month 24 of risdiplam treatment, 32% of patients demonstrated improvement (a change of ≥ 3) from baseline in MFM32 total score; 58% showed stabilization (a change of ≥ 0). Compared with an external comparator, a treatment difference of 3.12 (95% confidence interval [CI] 1.67-4.57) in favor of risdiplam was observed in MFM-derived scores. Overall, gains in motor function at month 12 were maintained or improved upon at month 24. In patients initially receiving placebo, MFM32 remained stable compared with baseline (0.31 [95% CI - 0.65 to 1.28]) after 12 months of risdiplam; 16% of patients improved their score and 59% exhibited stabilization. The safety profile after 24 months was consistent with that observed after 12 months. Risdiplam over 24 months resulted in further improvement or stabilization in motor function, confirming the benefit of longer-term treatment.

A Mixed-method Approach to Develop an Ambulatory Module of the SMA Independence Scale

BACKGROUND

Limited qualitative data exist on the symptoms and impacts of spinal muscular atrophy (SMA) experienced by ambulant individuals. An ambulant module of the SMA Independence Scale (SMAIS) was developed to quantify the assistance required to perform everyday mobility-related activities.

OBJECTIVE

The objective of this study was to develop a patient-centered module that provides key insights into what constitutes independence for ambulant and near-ambulant individuals with SMA.

METHODS

A stepwise, mixed-method approach was used. Semi-structured interviews were conducted in three waves with individuals with SMA and caregivers of children with SMA who were ambulant or near-ambulant (can walk ≥5 steps with support). Wave 1 interviews (n = 20) focused on concept elicitation. Wave 2 and 3 interviews (n = 15, both) involved completion and cognitive debriefing of items generated based on Wave 1 interviews. Therapeutic area experts were consulted throughout all key steps of the study. In particular, feedback was provided for item refinement and response option decisions. A macro-level preliminary, exploratory analysis, using Rasch Measurement Theory (RMT), provided insight on measurement properties.

RESULTS

Wave 1 resulted in 42 mobility and 11 instrumental activity of daily living (iADL) items. During Wave 2, participants defined independence as completing a task with supportive aids but without help from another person, leading to item refinement and modifications to the response scale. Lack of conceptual relevance and ceiling effects led to the removal of all iADL items after Wave 2, and 41 mobility items were tested in Wave 3. Final exploratory RMT and item refinement to reduce overlap led to a 27-item set related to mobility tasks.

CONCLUSIONS

Our study provides preliminary support for using the 27-item SMAIS-Ambulatory Module for ambulant or near-ambulant individuals with SMA. Larger-scale analyses to further assess the psychometric properties of the scale are warranted.

Use of MFM-20 to monitor SMA types 1 and 2 patients treated with nusinersen

OBJECTIVE

To evaluate sensitivity to change and discriminant validity of the 20-item Motor Function Measure (MFM-20) in 2-7-year-old patients with spinal muscular atrophy types 1 (SMA1) or 2 (SMA2) treated with nusinersen.

METHODS

Children aged 2 to 7 years old with SMA1 or SMA2 treated with nusinersen were assessed at least three times using the MFM-20 over an average follow-up time of 17 months. Evolution of 4-month-standardized MFM-20 scores was calculated for each MFM-20 domain (D1 standing and transfers, D2 axial and proximal, D3 distal) and for the total score (TS).

RESULTS

Included in the study were 22 SMA1 subjects and 19 SMA2 subjects. Baseline MFM scores were significantly lower in patients with SMA1 than SMA2 (TS 29.5% vs. 48.3%, D1 4.5% vs. 10.6%, D2 43.6% vs. 72.6%, D3 51.2% vs. 75.0%). When considering the mean change during nusinersen treatment, standardized over a 4-month period, TS was improved for both SMA1 (+ 4.1%, SRM 1.5) and SMA2 (+ 2.8%, SRM 0.89) patients. For SMA1 patients, considerable changes were observed in D2 (+ 6.2%, SRM 0.89) and D3 (+ 6.0%, SRM 0.72), whereas the change in D1 was small (+ 0.5%, SRM 0.44). In SMA2 2 subjects, D3 was improved to a larger extent (+ 4.2%, SRM 0.53) than D1 (+ 1.8% SRM 0.63) or D2 (+ 3.2%, SRM 0.69).

CONCLUSION

Our results validate use of MFM-20 to monitor function of young SMA1 and SMA2 subjects treated with nusinersen. Significant motor function improvements following treatment were observed in both SMA1 and SMA2 patients.