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.

Determining minimal clinically important differences in the North Star Ambulatory Assessment (NSAA) for patients with Duchenne muscular dystrophy

The North Star ambulatory assessment (NSAA) is a functional motor outcome measure in Duchenne muscular dystrophy (DMD), widely used in clinical trials and natural history studies, as well as in clinical practice. However, little has been reported on the minimal clinically important difference (MCID) of the NSAA. The lack of established MCID estimates for NSAA presents challenges in interpreting the significance of the results of this outcome measure in clinical trials, natural history studies and clinical practice. Combining statistical approaches and patient perspectives, this study estimated MCID for NSAA using distribution-based estimates of 1/3 standard deviation (SD) and standard error of measurement (SEM), an anchor-based approach, with six-minute walk distance (6MWD) as the anchor, and evaluation of patient and parent perception using participant-tailored questionnaires. The MCID for NSAA in boys with DMD aged 7 to 10 years based on 1/3 SD ranged from 2.3-2.9 points, and that on SEM ranged from 2.9-3.5 points. Anchored on the 6MWD, the MCID for NSAA was estimated as 3.5 points. When the impact on functional abilities was considered using participant response questionnaires, patients and parent perceived a complete loss of function in a single item or deterioration of function in one to two items of the assessment as an important change. Our study examines MCID estimates for total NSAA scores using multiple approaches, including the impact of patient and parent perspective on within scale changes in items based on complete loss of function and deterioration of function, and provides new insight on evaluation of differences in these widely used outcome measure in DMD.

Risdiplam in Types 2 and 3 spinal muscular atrophy: a randomised, placebo-controlled, dose-finding trial followed by 24 months of treatment

BACKGROUND

Spinal muscular atrophy (SMA) is caused by reduced levels of survival of motor neuron (SMN) protein due to deletions and/or mutations in the SMN1 gene. Risdiplam is an orally administered molecule that modifies SMN2 pre-mRNA splicing to increase functional SMN protein.

METHODS

SUNFISH Part 1 was a dose-finding study conducted in 51 individuals with Types 2 and 3 SMA aged 2-25 years. A dose-escalation method was used to identify the appropriate dose for the subsequent pivotal Part 2. Individuals were randomised (2:1) to risdiplam or placebo at escalating dose levels for a minimum 12-week, double-blind, placebo-controlled period, followed by treatment for 24 months. The dose selection for Part 2 was based on safety, tolerability, pharmacokinetic and pharmacodynamic data. Exploratory efficacy was also measured.

RESULTS

There was no difference in safety findings for all assessed dose levels. A dose-dependent increase in blood SMN protein was observed; a median two-fold increase was obtained within 4 weeks of treatment initiation at the highest dose level. The increase in SMN protein was sustained over 24 months of treatment. Exploratory efficacy showed improvement or stabilisation in motor function. The pivotal dose selected for Part 2 was 5 mg for patients with a body weight ≥20 kg or 0.25 mg/kg for patients <20 kg.

CONCLUSIONS

SUNFISH Part 1 demonstrated a two-fold increase in SMN protein after treatment with risdiplam. The observed safety profile supported the initiation of the pivotal Part 2 study. The long-term efficacy and safety of risdiplam is being assessed with ongoing treatment.

Safety and efficacy of once-daily risdiplam in type 2 and non-ambulant type 3 spinal muscular atrophy (SUNFISH part 2): a phase 3, double-blind, randomised, placebo-controlled trial

BACKGROUND

Risdiplam is an oral small molecule approved for the treatment of patients with spinal muscular atrophy, with approval for use in patients with type 2 and type 3 spinal muscular atrophy granted on the basis of unpublished data. The drug modifies pre-mRNA splicing of the SMN2 gene to increase production of functional SMN. We aimed to investigate the safety and efficacy of risdiplam in patients with type 2 or non-ambulant type 3 spinal muscular atrophy.

METHODS

In this phase 3, randomised, double-blind, placebo-controlled study, patients aged 2-25 years with confirmed 5q autosomal recessive type 2 or type 3 spinal muscular atrophy were recruited from 42 hospitals in 14 countries across Europe, North America, South America, and Asia. Participants were eligible if they were non-ambulant, could sit independently, and had a score of at least 2 in entry item A of the Revised Upper Limb Module. Patients were stratified by age and randomly assigned (2:1) to receive either daily oral risdiplam, at a dose of 5·00 mg (for individuals weighing ≥20 kg) or 0·25 mg/kg (for individuals weighing <20 kg), or daily oral placebo (matched to risdiplam in colour and taste). Randomisation was conducted by permutated block randomisation with a computerised system run by an external party. Patients, investigators, and all individuals in direct contact with patients were masked to treatment assignment. The primary endpoint was the change from baseline in the 32-item Motor Function Measure total score at month 12. All individuals who were randomly assigned to risdiplam or placebo, and who did not meet the prespecified missing item criteria for exclusion, were included in the primary efficacy analysis. Individuals who received at least one dose of risdiplam or placebo were included in the safety analysis. SUNFISH is registered with ClinicalTrials.gov, NCT02908685. Recruitment is closed; the study is ongoing.

FINDINGS

Between Oct 9, 2017, and Sept 4, 2018, 180 patients were randomly assigned to receive risdiplam (n=120) or placebo (n=60). For analysis of the primary endpoint, 115 patients from the risdiplam group and 59 patients from the placebo group were included. At month 12, the least squares mean change from baseline in 32-item Motor Function Measure was 1·36 (95% CI 0·61 to 2·11) in the risdiplam group and -0·19 (-1·22 to 0·84) in the placebo group, with a treatment difference of 1·55 (0·30 to 2·81, p=0·016) in favour of risdiplam. 120 patients who received risdiplam and 60 who received placebo were included in safety analyses. Adverse events that were reported in at least 5% more patients who received risdiplam than those who received placebo were pyrexia (25 [21%] of 120 patients who received risdiplam vs ten [17%] of 60 patients who received placebo), diarrhoea (20 [17%] vs five [8%]), rash (20 [17%] vs one [2%]), mouth and aphthous ulcers (eight [7%] vs 0), urinary tract infection (eight [7%] vs 0), and arthralgias (six [5%] vs 0). The incidence of serious adverse events was similar between treatment groups (24 [20%] of 120 patients in the risdiplam group; 11 [18%] of 60 patients in the placebo group), with the exception of pneumonia (nine [8%] in the risdiplam group; one [2%] in the placebo group).

INTERPRETATION

Risdiplam resulted in a significant improvement in motor function compared with placebo in patients aged 2-25 years with type 2 or non-ambulant type 3 spinal muscular atrophy. Our exploratory subgroup analyses showed that motor function was generally improved in younger individuals and stabilised in older individuals, which requires confirmation in further studies. SUNFISH part 2 is ongoing and will provide additional evidence regarding the long-term safety and efficacy of risdiplam.

FUNDING

F Hoffmann-La Roche.

Nusinersen improves walking distance and reduces fatigue in later-onset spinal muscular atrophy

Introduction

Ambulatory individuals with spinal muscular atrophy (SMA) experience muscle weakness, gait impairments, and fatigue that affect their walking ability. Improvements have been observed in motor function in children treated with nusinersen, but its impact on fatigue has not been studied.

Methods

Post hoc analyses were used to examine changes in 6‐minute walk test (6MWT) distance and fatigue in children and adolescents with SMA type II and III who received their first dose of nusinersen in the phase Ib/IIa, open‐label CS2 study and were ambulatory during CS2 or the extension study, CS12.

Results

Fourteen children performed the 6MWT. Median (25th, 75th percentile) distance walked increased over time by 98.0 (62.0, 135.0) meters at day 1050, whereas median fatigue changed by −3.8% (−19.7%, 1.4%).

Discussion

These results support previous studies demonstrating clinically meaningful effects of nusinersen on motor function in children and adolescents with later‐onset SMA.

Evaluator Training and Reliability for SMA Global Nusinersen Trials1

Background:

Training methodology was established to optimize reliability of outcome measures in the nusinersen clinical trials. The Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND), Hammersmith Functional Motor Scale Expanded (HFMSE), and Revised Upper Limb (RULM) were primary or secondary outcomes.

Methods:

Video review, quarterly conference calls, and item scoring checks supported evaluator competence. Baseline and screening along with video review established intra and inter-rater reliability.

Results:

Inter and intra-rater reliability were both excellent. Intraclass correlation coefficients (ICC) ranged between 0.906–0.994 across initial training meetings and 0.824–0.996 across annual retraining meetings. This was similar for CHOP INTEND (ICC = 0.824–0.951), HFMSE (ICC = 0.981–0.996), and RULM (ICC = 0.966–0.990). Intra-rater reliability for the CHOP INTEND, HFMSE, and RULM were ICC = 0.895 (95% CI: 0.852–0.926; n = 116), ICC = 0.959 (95% CI: 0.942–0.971; n = 125), and ICC = 0.948 (95% CI: 0.927–0.963; n = 126) respectively.

Conclusions:

Rigorous evaluator training ensures reliability of assessment of subjects with spinal muscular atrophy (SMA) in multicenter international trials.

Ambulatory function in spinal muscular atrophy: Age-related patterns of progression

Individuals with spinal muscular atrophy (SMA) type 3 are able to walk but they have weakness, gait impairments and fatigue. Our primary study objective was to examine longitudinal changes in the six-minute walk test (6MWT) and to evaluate whether age and SMA type 3 subtype are associated with decline in ambulatory function. Data from three prospective natural history studies were used. Seventy-three participants who performed the 6MWT more than once, at least 6 months apart, were included; follow-up ranged from 0.5-9 years. Only data from patients who completed the 6MWT were included. The mean age of the participants was 13.5 years (range 2.6-49.1), with 52 having disease onset before age 3 years (type 3A). At baseline, type 3A participants walked a shorter distance on average (257.1 m) than type 3B participants (390.2 m) (difference = 133.1 m, 95% confidence interval [CI] 71.8-194.3, p < 0.001). Distance walked was weakly associated with age (r = 0.25, p = 0.04). Linear mixed effects models were used to estimate the mean annual rate of change. The overall mean rate of change was -7.8 m/year (95% CI -13.6 --2.0, p = 0.009) and this did not differ by subtype (type 3A: -8.5 m/year, type 3B: -6.6 m/year, p = 0.78), but it did differ by age group (< 6: 9.8 m/year; 6-10: -7.9 m/year; 11-19: -20.8 m/year; ≥ 20: -9.7 m/year; p = 0.005). Our results showed an overall decline on the 6MWT over time, but different trajectories were observed depending on age. Young ambulant SMA patients gain function but in adolescence, patients lose function. Future clinical trials in ambulant SMA patients should consider in their design the different trajectories of ambulatory function over time, based on age.

Nusinersen versus Sham Control in Later-Onset Spinal Muscular Atrophy

BACKGROUND

Nusinersen is an antisense oligonucleotide drug that modulates pre-messenger RNA splicing of the survival motor neuron 2 ( SMN2) gene. It has been developed for the treatment of spinal muscular atrophy (SMA).

METHODS

We conducted a multicenter, double-blind, sham-controlled, phase 3 trial of nusinersen in 126 children with SMA who had symptom onset after 6 months of age. The children were randomly assigned, in a 2:1 ratio, to undergo intrathecal administration of nusinersen at a dose of 12 mg (nusinersen group) or a sham procedure (control group) on days 1, 29, 85, and 274. The primary end point was the least-squares mean change from baseline in the Hammersmith Functional Motor Scale-Expanded (HFMSE) score at 15 months of treatment; HFMSE scores range from 0 to 66, with higher scores indicating better motor function. Secondary end points included the percentage of children with a clinically meaningful increase from baseline in the HFMSE score (≥3 points), an outcome that indicates improvement in at least two motor skills.

RESULTS

In the prespecified interim analysis, there was a least-squares mean increase from baseline to month 15 in the HFMSE score in the nusinersen group (by 4.0 points) and a least-squares mean decrease in the control group (by -1.9 points), with a significant between-group difference favoring nusinersen (least-squares mean difference in change, 5.9 points; 95% confidence interval, 3.7 to 8.1; P<0.001). This result prompted early termination of the trial. Results of the final analysis were consistent with results of the interim analysis. In the final analysis, 57% of the children in the nusinersen group as compared with 26% in the control group had an increase from baseline to month 15 in the HFMSE score of at least 3 points (P<0.001), and the overall incidence of adverse events was similar in the nusinersen group and the control group (93% and 100%, respectively).

CONCLUSIONS

Among children with later-onset SMA, those who received nusinersen had significant and clinically meaningful improvement in motor function as compared with those in the control group. (Funded by Biogen and Ionis Pharmaceuticals; CHERISH ClinicalTrials.gov number, NCT02292537 .).

Diagnosis and management of spinal muscular atrophy: Part 1: Recommendations for diagnosis, rehabilitation, orthopedic and nutritional care

Spinal muscular atrophy (SMA) is a severe neuromuscular disorder due to a defect in the survival motor neuron 1 (SMN1) gene. Its incidence is approximately 1 in 11,000 live births. In 2007, an International Conference on the Standard of Care for SMA published a consensus statement on SMA standard of care that has been widely used throughout the world. Here we report a two-part update of the topics covered in the previous recommendations. In part 1 we present the methods used to achieve these recommendations, and an update on diagnosis, rehabilitation, orthopedic and spinal management; and nutritional, swallowing and gastrointestinal management. Pulmonary management, acute care, other organ involvement, ethical issues, medications, and the impact of new treatments for SMA are discussed in part 2.

Clinical phenotypes and trajectories of disease progression in type 1 spinal muscular atrophy

The advent of clinical trials has highlighted the need for natural history studies reporting disease progression in type 1 spinal muscular atrophy. The aim of this study was to assess functional changes using the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) scale in a cohort of type 1 infants. Nutritional and respiratory longitudinal data were also recorded. Patients were classified according to the severity of the phenotype and age of onset. SMN2 copies were also assessed. Twenty patients were included, eight with early onset most severe phenotype, eight with the more typical type 1 phenotype and 4, who achieved some head control, with a milder phenotype. Both baseline values and trajectories of progression were different in the three subgroups (p = 0.0001). Infants with the most severe phenotype had the lowest scores (below 20) on their first assessment and had the most rapid decline. Those with the typical phenotype had scores generally between 20 and 40 and also had a fast decline. The infants with the milder phenotype had the highest scores, generally above 35, and a much slower deterioration. Infants with three SMN2 copies had an overall milder phenotype and milder progression while two SMN2 copies were found in all three subgroups.

Content validity and clinical meaningfulness of the HFMSE in spinal muscular atrophy

BACKGROUND

Reports on the clinical meaningfulness of outcome measures in spinal muscular atrophy (SMA) are rare. In this two-part study, our aim was to explore patients' and caregivers' views on the clinical relevance of the Hammersmith Functional Motor Scale Expanded- (HFMSE).

METHODS

First, we used focus groups including SMA patients and caregivers to explore their views on the clinical relevance of the individual activities included in the HFMSE. Then we asked caregivers to comment on the clinical relevance of possible changes of HFMSE scores over time. As functional data of individual patients were available, some of the questions were tailored according to their functional level on the HFMSE.

RESULTS

Part 1: Sixty-three individuals participated in the focus groups. This included 30 caregivers, 25 patients and 8 professionals who facilitated the discussion. The caregivers provided a comparison to activities of daily living for each of the HFMSE items. Part 2: One hundred and forty-nine caregivers agreed to complete the questionnaire: in response to a general question, 72% of the caregivers would consider taking part in a clinical trial if the treatment was expected to slow down deterioration, 88% if it would stop deterioration and 97% if the treatment was expected to produce an improvement. Caregivers were informed of the first three items that their child could not achieve on the HFMSE. In response 75% indicated a willingness to take part in a clinical trial if they could achieve at least one of these abilities, 89% if they could achieve two, and 100% if they could achieve more than 2.

CONCLUSIONS

Our findings support the use of the HFMSE as a key outcome measure in SMA clinical trials because the individual items and the detected changes have clear content validity and clinical meaningfulness for patients and their caregivers.

Revised Hammersmith Scale for spinal muscular atrophy: A SMA specific clinical outcome assessment tool

Recent translational research developments in Spinal Muscular Atrophy (SMA), outcome measure design and demands from regulatory authorities require that clinical outcome assessments are 'fit for purpose'. An international collaboration (SMA REACH UK, Italian SMA Network and PNCRN USA) undertook an iterative process to address discontinuity in the recorded performance of the Hammersmith Functional Motor Scale Expanded and developed a revised functional scale using Rasch analysis, traditional psychometric techniques and the application of clinical sensibility via expert panels. Specifically, we intended to develop a psychometrically and clinically robust functional clinician rated outcome measure to assess physical abilities in weak SMA type 2 through to strong ambulant SMA type 3 patients. The final scale, the Revised Hammersmith Scale (RHS) for SMA, consisting of 36 items and two timed tests, was piloted in 138 patients with type 2 and 3 SMA in an observational cross-sectional multi-centre study across the three national networks. Rasch analysis demonstrated very good fit of all 36 items to the construct of motor performance, good reliability with a high Person Separation Index PSI 0.98, logical and hierarchical scoring in 27/36 items and excellent targeting with minimal ceiling. The RHS differentiated between clinically different groups: SMA type, World Health Organisation (WHO) categories, ambulatory status, and SMA type combined with ambulatory status (all p < 0.001). Construct and concurrent validity was also confirmed with a strong significant positive correlation with the WHO motor milestones rs = 0.860, p < 0.001. We conclude that the RHS is a psychometrically sound and versatile clinical outcome assessment to test the broad range of physical abilities of patients with type 2 and 3 SMA. Further longitudinal testing of the scale with regards change in scores over 6 and 12 months are required prior to its adoption in clinical trials.

Development of a patient-reported outcome measure for upper limb function in Duchenne muscular dystrophy: DMD Upper Limb PROM

AIM

To develop a patient-reported outcome measure (PROM) assessing upper limb function related to activities of daily living (ADL) that cannot be observed in a clinical setting, specifically for patients with Duchenne muscular dystrophy (DMD) across a wide age range, applicable in the different stages of the disease.

METHOD

The developmental process was based on US Food and Drug Administration guidelines. This included item generation from a systematic review of existing tools and expert opinion on task difficulty and relevance, involving individuals with DMD. Cultural aspects affecting ADL were taken into consideration to make this tool applicable to the broad DMD community. Items were selected in relation to a conceptual framework reflecting disease progression covering the full range of upper limb function across different ADL domains.

RESULTS

After pilot testing and iterative Rasch analyses, redundant or clinically irrelevant items were removed. The final questionnaire consists of 32 items covering four domains of ADL (food, self-care, household and environment, leisure and communication). Test-retest reliability was excellent.

INTERPRETATION

A DMD-specific upper limb PROM was developed on the basis of clinical relevance and psychometric robustness. Its main purpose is to document the patient self-reported natural history of DMD and assess the efficacy of interventions.

Spinal muscular atrophy functional composite score: A functional measure in spinal muscular atrophy

INTRODUCTION

With clinical trials underway, our objective was to construct a composite score of global function that could discriminate among people with spinal muscular atrophy (SMA).

METHODS

Data were collected from 126 participants with SMA types 2 and 3. Scores from the Hammersmith Functional Motor Scale-Expanded and Upper Limb Module were expressed as a percentage of the maximum score and 6-minute walk test as percent of predicted normal distance. A principal component analysis was performed on the correlation matrix for the 3 percentage scores.

RESULTS

The first principal component yielded a composite score with approximately equal weighting of the 3 components and accounted for 82% of the total variability. The SMA functional composite score, an unweighted average of the 3 individual percentage scores, correlated almost perfectly with the first principal component.

CONCLUSIONS

This combination of measures broadens the spectrum of ability that can be quantified in type 2 and 3 SMA patients.

6 Minute walk test in Duchenne MD patients with different mutations: 12 month changes

OBJECTIVE

In the last few years some of the therapeutical approaches for Duchenne muscular dystrophy (DMD) are specifically targeting distinct groups of mutations, such as deletions eligible for skipping of individual exons. The aim of this observational study was to establish whether patients with distinct groups of mutations have different profiles of changes on the 6 minute walk test (6MWT) over a 12 month period.

METHODS

The 6MWT was performed in 191 ambulant DMD boys at baseline and 12 months later. The results were analysed using a test for heterogeneity in order to establish possible differences among different types of mutations (deletions, duplications, point mutations) and among subgroups of deletions eligible to skip individual exons.

RESULTS

At baseline the 6MWD ranged between 180 and 560,80 metres (mean 378,06, SD 74,13). The 12 month changes ranged between -325 and 175 (mean -10.8 meters, SD 69.2). Although boys with duplications had better results than those with the other types of mutations, the difference was not significant. Similarly, boys eligible for skipping of the exon 44 had better baseline results and less drastic changes than those eligible for skipping exon 45 or 53, but the difference was not significant.

CONCLUSIONS

even if there are some differences among subgroups, the mean 12 month changes in each subgroup were all within a narrow Range: from the mean of the whole DMD cohort. This information will be of help at the time of designing clinical trials with small numbers of eligible patients.

Development of the Performance of the Upper Limb module for Duchenne muscular dystrophy

AIM

An international Clinical Outcomes Group consisting of clinicians, scientists, patient advocacy groups, and industries identified a need for a scale to measure motor performance of the upper limb. We report the steps leading to the development of the Performance of the Upper Limb (PUL), a tool specifically designed for assessing upper limb function in ambulant and non-ambulant patients with Duchenne muscular dystrophy (DMD).

METHOD

The development of the PUL followed a number of steps, from the systematic review and a preliminary study exploring the suitability of the existing measures, to the application of a pilot version in a multicentric setting, with Rasch analysis of the preliminary results, leading to a revised pro forma.

RESULTS

The PUL was specifically designed for DMD, with a conceptual framework reflecting the progression of weakness and natural history of functional decline in DMD. Modern psychometric methods were used to create a scale with robust internal reliability, validity, and hierarchical scalability; males with DMD and their families were involved iteratively throughout the process of the clinician-reported outcome assessment tool development to establish clinical meaningfulness and relevance of individual PUL items to activities of daily living.

INTERPRETATION

The module was developed using innovative approaches and will be useful for designing clinical trials.

A critical review of functional assessment tools for upper limbs in Duchenne muscular dystrophy

The recent development of therapeutic approaches for Duchenne muscular dystrophy (DMD) has highlighted the need to identify clinical outcome measures for planned efficacy studies. Although several studies have reported the value of functional scales, timed tests, and measures of endurance aimed at ambulant individuals, less has been done to identify reliable measures of function in individuals who have lost ambulation. The aim of this paper is to provide a critical review of the existing literature on functional measures assessing upper extremity function in DMD. Four observer-rated, performance-based measures and four self-reported scales have been previously used in DMD. Each scale provides useful information but none reflects all the different levels of functional ability in activities of daily living observed in individuals with DMD at different ages.

Reliability of the North Star Ambulatory Assessment in a multicentric setting

The aim of this study was to investigate the suitability of the North Star Ambulatory Assessment as a possible outcome measure in multicentric clinical trials. More specifically we wished to investigate the level of training needed for achieving a good interobserver reliability in a multicentric setting. The scale was specifically designed for ambulant children with Duchenne Muscular Dystrophy and includes 17 items that are relevant for this cohort. Thirteen Italian centers participated in the study. In the first phase of the study we provided two training videos and an example of the scale performed on a child. After the first session of training, all the 13 examiners were asked to send a video with an assessment performed in their centre and to score all the videos collected. There were no difficulties in performing the items and in obtaining adequate videos with a hand held camera but the results showed a poor interobserver reliability (<.5). After a second training session with review and discussion of the videos previously scored, the same examiners were asked to score three new videos. The results of this session had an excellent interobserver reliability (.995). The level of agreement was maintained even when the same videos were rescored after a month, showing a significant intra-observer reliability (.95). Our results suggest that the NSAA is a test that can be easily performed, completed in 10 min and can be used in a multicentric setting, providing that adequate training is administered.

Daily salbutamol in young patients with SMA type II

The aim of this open pilot study was to establish the profile of tolerability and clinical response of salbutamol (albuterol) in a cohort of young children affected by type II spinal muscular atrophy (SMA). Twenty-three children between 30 months and 6 years of age were treated with salbutamol (2 mg three times a day) for 1 year. All children were longitudinally assessed using the Hammersmith motor functional scale 6 months before treatment started (T0), at baseline (T1) and 6 and 12 months later. There was no significant change in function between T0 and T1 assessments, but the functional scores recorded after 6 and 12 months of treatment were significantly higher than those recorded at baseline (p=0.006). Our results suggest that salbutamol may be beneficial to SMA patients without producing any major side effect. Larger prospective randomized, double-blind, placebo controlled trials are needed to confirm these preliminary findings.