Functional outcome measures in young, steroid-naïve boys with Duchenne muscular dystrophy.

The purpose of this study was to quantitate motor performance in 196 genetically confirmed steroid-naïve boys with Duchenne muscular dystrophy (DMD), to evaluate the test-retest reliability of measures of motor performance in young DMD boys, and to assess correlations among the different functional outcomes including timed tests. Boys aged 4-7 years were recruited in the FOR-DMD study, a comparative effectiveness study of different steroid regimens in DMD. Eligible boys had to be able to rise from the floor independently and to perform pulmonary function testing consistently. The boys were evaluated with standardized assessments at the screening and baseline visits at 32 sites in 5 countries (US, UK, Canada, Italy, Germany). Assessments included timed rise from floor, timed 10 m walk/run, six-minute walk distance, North Star Ambulatory Assessment (NSAA) and forced vital capacity (FVC). Mean age at baseline was 5.9 years (range 4.1-8.1 years). Test-retest reliability was high for functional assessments, regardless of time lag between assessments (up to 90 days) and for the majority of age groups. Correlations were strong among the functional measures and timed tests, less so with FVC. Physiotherapy measures are reliable in a young, steroid-naïve population and rise from floor velocity appears to be a sensitive measure of strength in this population.

Effect of Different Corticosteroid Dosing Regimens on Clinical Outcomes in Boys With Duchenne Muscular Dystrophy: A Randomized Clinical Trial.

Importance: Corticosteroids improve strength and function in boys with Duchenne muscular dystrophy. However, there is uncertainty regarding the optimum regimen and dosage. Objective: To compare efficacy and adverse effects of the 3 most frequently prescribed corticosteroid regimens in boys with Duchenne muscular dystrophy. Design, Setting, and Participants: Double-blind, parallel-group randomized clinical trial including 196 boys aged 4 to 7 years with Duchenne muscular dystrophy who had not previously been treated with corticosteroids; enrollment occurred between January 30, 2013, and September 17, 2016, at 32 clinic sites in 5 countries. The boys were assessed for 3 years (last participant visit on October 16, 2019). Interventions: Participants were randomized to daily prednisone (0.75 mg/kg) (n = 65), daily deflazacort (0.90 mg/kg) (n = 65), or intermittent prednisone (0.75 mg/kg for 10 days on and then 10 days off) (n = 66). Main Outcomes and Measures: The global primary outcome comprised 3 end points: rise from the floor velocity (in rise/seconds), forced vital capacity (in liters), and participant or parent global satisfaction with treatment measured by the Treatment Satisfaction Questionnaire for Medication (TSQM; score range, 0 to 100), each averaged across all study visits after baseline. Pairwise group comparisons used a Bonferroni-adjusted significance level of .017. Results: Among the 196 boys randomized (mean age, 5.8 years [SD, 1.0 years]), 164 (84%) completed the trial. Both daily prednisone and daily deflazacort were more effective than intermittent prednisone for the primary outcome (P < .001 for daily prednisone vs intermittent prednisone using a global test; P = .017 for daily deflazacort vs intermittent prednisone using a global test) and the daily regimens did not differ significantly (P = .38 for daily prednisone vs daily deflazacort using a global test). The between-group differences were principally attributable to rise from the floor velocity (0.06 rise/s [98.3% CI, 0.03 to 0.08 rise/s] for daily prednisone vs intermittent prednisone [P = .003]; 0.06 rise/s [98.3% CI, 0.03 to 0.09 rise/s] for daily deflazacort vs intermittent prednisone [P = .017]; and -0.004 rise/s [98.3% CI, -0.03 to 0.02 rise/s] for daily prednisone vs daily deflazacort [P = .75]). The pairwise comparisons for forced vital capacity and TSQM global satisfaction subscale score were not statistically significant. The most common adverse events were abnormal behavior (22 [34%] in the daily prednisone group, 25 [38%] in the daily deflazacort group, and 24 [36%] in the intermittent prednisone group), upper respiratory tract infection (24 [37%], 19 [29%], and 24 [36%], respectively), and vomiting (19 [29%], 17 [26%], and 15 [23%]). Conclusions and Relevance: Among patients with Duchenne muscular dystrophy, treatment with daily prednisone or daily deflazacort, compared with intermittent prednisone alternating 10 days on and 10 days off, resulted in significant improvement over 3 years in a composite outcome comprising measures of motor function, pulmonary function, and satisfaction with treatment; there was no significant difference between the 2 daily corticosteroid regimens. The findings support the use of a daily corticosteroid regimen over the intermittent prednisone regimen tested in this study as initial treatment for boys with Duchenne muscular dystrophy. Trial Registration: ClinicalTrials.gov Identifier: NCT01603407.

A checklist for clinical trials in rare disease: obstacles and anticipatory actions-lessons learned from the FOR-DMD trial.

BACKGROUND: Trials in rare diseases have many challenges, among which are the need to set up multiple sites in different countries to achieve recruitment targets and the divergent landscape of clinical trial regulations in those countries. Over the past years, there have been initiatives to facilitate the process of international study set-up, but the fruits of these deliberations require time to be operationally in place. FOR-DMD (Finding the Optimum Steroid Regimen for Duchenne Muscular Dystrophy) is an academic-led clinical trial which aims to find the optimum steroid regimen for Duchenne muscular dystrophy, funded by the National Institutes of Health (NIH) for 5 years (July 2010 to June 2015), anticipating that all sites (40 across the USA, Canada, the UK, Germany and Italy) would be open to recruitment from July 2011. However, study start-up was significantly delayed and recruitment did not start until January 2013. METHOD: The FOR-DMD study is used as an example to identify systematic problems in the set-up of international, multi-centre clinical trials. The full timeline of the FOR-DMD study, from funding approval to site activation, was collated and reviewed. Systematic issues were identified and grouped into (1) study set-up, e.g. drug procurement; (2) country set-up, e.g. competent authority applications; and (3) site set-up, e.g. contracts, to identify the main causes of delay and suggest areas where anticipatory action could overcome these obstacles in future studies. RESULTS: Time from the first contact to site activation across countries ranged from 6 to 24 months. Reasons of delay were universal (sponsor agreement, drug procurement, budgetary constraints), country specific (complexity and diversity of regulatory processes, indemnity requirements) and site specific (contracting and approvals). The main identified obstacles included (1) issues related to drug supply, (2) NIH requirements regarding contracting with non-US sites, (3) differing regulatory requirements in the five participating countries, (4) lack of national harmonisation with contracting and the requirement to negotiate terms and contract individually with each site and (5) diversity of languages needed for study materials. Additionally, as with many academic-led studies, the FOR-DMD study did not have access to the infrastructure and expertise that a contracted research organisation could provide, organisations often employed in pharmaceutical-sponsored studies. This delay impacted recruitment, challenged the clinical relevance of the study outcomes and potentially delayed the delivery of the best treatment to patients. CONCLUSION: Based on the FOR-DMD experience, and as an interim solution, we have devised a checklist of steps to not only anticipate and minimise delays in academic international trial initiation but also identify obstacles that will require a concerted effort on the part of many stakeholders to mitigate.

Developing standardized corticosteroid treatment for Duchenne muscular dystrophy.

Despite corticosteroids being the only treatment documented to improve strength and function in boys with Duchenne muscular dystrophy (DMD) corticosteroid prescription is inconsistent and in some countries, corticosteroids are not prescribed. We are conducting a clinical trial that (1) compares the 3 most frequently prescribed corticosteroid regimes; (2) standardizes treatment of DMD complications; and (3) standardizes prevention of corticosteroid side effects. Investigators at 38 sites in 5 countries plan to recruit 300 boys aged 4-7 who are randomly assigned to one of three regimens: daily prednisone; daily deflazacort; or intermittent prednisone (10days on/10days off). Boys are followed for a minimum of 3years to assess the relative effectiveness and adverse event profiles of the different regimens. The primary outcome is a 3-dimensional variable consisting of log-transformed time to rise from the floor, forced vital capacity, and subject/parent satisfaction with treatment, each averaged over all post-baseline visits. The study protocol includes evidence- and consensus-based treatment of DMD complications and of corticosteroid side effects. This study seeks to establish a standard corticosteroid regimen for DMD. Since all new interventions for DMD are being developed as add-on therapies to corticosteroids, defining the optimum regimen is of importance for all new treatments.

One clinic's experience with carbon fiber orthoses in neuromuscular disease.

INTRODUCTION: The purpose of this study was to summarize our experience with off-the-shelf anterior shell carbon fiber ankle-foot orthoses (CFAFOs) prescribed to adult neuromuscular patients in an outpatient clinic. METHODS: We studied ambulatory patients who were seen in Muscular Dystrophy Association or amyotrophic lateral sclerosis clinics between 2011 and 2014 and prescribed anterior shell CFAFOs. Charts were reviewed with attention to diagnosis, satisfaction with use, and reasons for acceptance or rejection. We included individuals who were currently using AFOs and those being prescribed AFOs for the first time. We were especially interested in reasons for acceptance or rejection of the orthosis. RESULTS: Two hundred eighty-three charts were reviewed. Of these, 109 of 123 (89%) patients were satisfied or extremely satisfied with the anterior shell CFAFOs, including 38 who had previously used other styles. CONCLUSION: Anterior shell CFAFOs should be considered for most neuromuscular patients with distal leg weakness. Muscle Nerve 55: 202-205, 2017.

Health Behavior Change Interventions for Teenage and Young Adult Cancer Survivors: A Systematic Review.

PURPOSE: It is important that teenage and young adult (TYA) cancer survivors adopt a healthy lifestyle, since health vulnerabilities associated with their diagnosis and treatment may be exacerbated by poor health behaviors. This review aims to synthesize the current literature on health behavior change interventions created specifically for TYA-aged cancer survivors. METHOD: MEDLINE, EMBASE, PsycINFO, and CINAHL databases were searched for studies investigating interventions targeting one or more health behaviors, including: physical activity, diet, smoking cessation, and alcohol consumption. Studies were eligible for review if the study population were defined as TYA cancer survivors and the mean age of the sample was younger than 30 years of age. RESULTS: Twelve studies were identified, of which nine were randomized controlled trials. Physical activity was the most commonly targeted health behavior. Six of the 12 interventions included within this review were successful in changing health behavior. Due to the heterogeneity of intervention characteristics, the relationship between intervention efficacy or outcome and intervention content, delivery mode, or theoretical framework was not discernible. Nevertheless, trends emerged relating to the delivery and content of health behavior interventions designed specifically for TYA cancer survivors. CONCLUSION: More research is required to identify the most effective means of promoting health behavior change among the TYA cancer survivor population. Specifically, future research should focus on providing evidence of the efficiency and feasibility of interventions that use online technologies to facilitate remote intervention delivery and peer support.

Clinical phenotypes as predictors of the outcome of skipping around DMD exon 45.

OBJECTIVE: Exon-skipping therapies aim to convert Duchenne muscular dystrophy (DMD) into less severe Becker muscular dystrophy (BMD) by altering pre-mRNA splicing to restore an open reading frame, allowing translation of an internally deleted and partially functional dystrophin protein. The most common single exon deletion-exon 45 (Δ45)-may theoretically be treated by skipping of either flanking exon (44 or 46). We sought to predict the impact of these by assessing the clinical severity in dystrophinopathy patients. METHODS: Phenotypic data including clinical diagnosis, age at wheelchair use, age at loss of ambulation, and presence of cardiomyopathy were analyzed from 41 dystrophinopathy patients containing equivalent in-frame deletions. RESULTS: As expected, deletions of either exons 45 to 47 (Δ45-47) or exons 45 to 48 (Δ45-48) result in BMD in 97% (36 of 37) of subjects. Unexpectedly, deletion of exons 45 to 46 (Δ45-46) is associated with the more severe DMD phenotype in 4 of 4 subjects despite an in-frame transcript. Notably, no patients with a deletion of exons 44 to 45 (Δ44-45) were found within the United Dystrophinopathy Project database, and this mutation has only been reported twice before, which suggests an ascertainment bias attributable to a very mild phenotype. INTERPRETATION: The observation that Δ45-46 patients have typical DMD suggests that the conformation of the resultant protein may result in protein instability or altered binding of critical partners. We conclude that in DMD patients with Δ45, skipping of exon 44 and multiexon skipping of exons 46 and 47 (or exons 46-48) are better potential therapies than skipping of exon 46 alone.

SMA valiant trial: a prospective, double-blind, placebo-controlled trial of valproic acid in ambulatory adults with spinal muscular atrophy.

INTRODUCTION: An open-label trial suggested that valproic acid (VPA) improved strength in adults with spinal muscular atrophy (SMA). We report a 12-month, double-blind, cross-over study of VPA in ambulatory SMA adults. METHODS: There were 33 subjects, aged 20­55 years, included in this investigation. After baseline assessment, subjects were randomized to receive VPA (10­20 mg/kg/day) or placebo. At 6 months, patients were switched to the other group. Assessments were performed at 3, 6, and 12 months. The primary outcome was the 6-month change in maximum voluntary isometric contraction testing with pulmonary, electrophysiological, and functional secondary outcomes. RESULTS: Thirty subjects completed the study. VPA was well tolerated, and compliance was good. There was no change in primary or secondary outcomes at 6 or 12 months. CONCLUSIONS: VPA did not improve strength or function in SMA adults. The outcomes used are feasible and reliable and can be employed in future trials in SMA adults.

Skeletal health in Duchenne dystrophy: bone-size and subcranial dual-energy X-ray absorptiometry analyses.

INTRODUCTION: We performed subcranial and bone-size-adjusted whole body dual-energy X-ray absorptiometry (DXA) to evaluate skeletal health in Duchenne dystrophy (DMD). METHODS: Total body bone mineral density (TBBMD)-for-age, subcranial, and size-adjusted DXA analyses were performed on 22 DMD patients (5-17 years) and compared with 267 controls from a database. The skull contribution to total body bone mineral content (TBBMC) and corticosteroid effects were also examined. RESULTS: DMD boys had deficits in TBBMD-for-age (Z = -1.2), which increased with age. The skull's contribution to TBBMC decreased from 45% to 15% with growth. Z-scores for subcranial skeleton were significantly lower than TBBMC-for-area and TBBMD-for-age. CONCLUSIONS: Size-adjusted and subcranial analyses improve evaluation of whole body DXA. DMD boys have low BMD for size not commensurate with total body areal BMD-for-age. Bone fragility fractures in DMD may result from both decreased BMD and smaller bones. This information is vital to determine appropriate intervention. Muscle Nerve 49:512-519, 2014.

Bent spine syndrome as an early manifestation of myotonic dystrophy type 1.

Myotonic dystrophy type 1 (DM1) is highly variable systemic disorder with prominent myopathic involvement in distal limb, facial, and jaw muscles. Bent spine syndrome presents a diagnostic challenge, and usually, DM1 is not included in the differential. We report 2 cases of DM1 with bent spine syndrome. To further investigate this phenomenon, we compared weakness patterns in a cohort of DM1 with cohorts of amyotrophic lateral sclerosis and inclusion body myositis and found that neck extension weakness is most pronounced in DM1. Our findings emphasize the heterogeneity of DM1 and underscore the importance of considering DM1 as a cause of bent spine syndrome.

LTBP4 genotype predicts age of ambulatory loss in Duchenne muscular dystrophy.

OBJECTIVE: Duchenne muscular dystrophy (DMD) displays a clinical range that is not fully explained by the primary DMD mutations. Ltbp4, encoding latent transforming growth factor-ß binding protein 4, was previously discovered in a genome-wide scan as a modifier of murine muscular dystrophy. We sought to determine whether LTBP4 genotype influenced DMD severity in a large patient cohort. METHODS: We analyzed nonsynonymous single nucleotide polymorphisms (SNPs) from human LTBP4 in 254 nonambulatory subjects with known DMD mutations. These SNPs, V194I, T787A, T820A, and T1140M, form the VTTT and IAAM LTBP4 haplotypes. RESULTS: Individuals homozygous for the IAAM LTBP4 haplotype remained ambulatory significantly longer than those heterozygous or homozygous for the VTTT haplotype. Glucocorticoid-treated patients who were IAAM homozygotes lost ambulation at 12.5 ± 3.3 years compared to 10.7 ± 2.1 years for treated VTTT heterozygotes or homozygotes. IAAM fibroblasts exposed to transforming growth factor (TGF) ß displayed reduced phospho-SMAD signaling compared to VTTT fibroblasts, consistent with LTBP4' role as a regulator of TGFß. INTERPRETATION: LTBP4 haplotype influences age at loss of ambulation, and should be considered in the management of DMD patients.

Mutational spectrum of DMD mutations in dystrophinopathy patients: application of modern diagnostic techniques to a large cohort.

Mutations in the DMD gene, encoding the dystrophin protein, are responsible for the dystrophinopathies Duchenne Muscular Dystrophy (DMD), Becker Muscular Dystrophy (BMD), and X-linked Dilated Cardiomyopathy (XLDC). Mutation analysis has traditionally been challenging, due to the large gene size (79 exons over 2.2 Mb of genomic DNA). We report a very large aggregate data set comprised of DMD mutations detected in samples from patients enrolled in the United Dystrophinopathy Project, a multicenter research consortium, and in referral samples submitted for mutation analysis with a diagnosis of dystrophinopathy. We report 1,111 mutations in the DMD gene, including 891 mutations with associated phenotypes. These results encompass 506 point mutations (including 294 nonsense mutations) and significantly expand the number of mutations associated with the dystrophinopathies, highlighting the utility of modern diagnostic techniques. Our data supports the uniform hypermutability of CGA>TGA mutations, establishes the frequency of polymorphic muscle (Dp427m) protein isoforms and reveals unique genomic haplotypes associated with "private" mutations. We note that 60% of these patients would be predicted to benefit from skipping of a single DMD exon using antisense oligonucleotide therapy, and 62% would be predicted to benefit from an inclusive multiexonskipping approach directed toward exons 45 through 55.

A phase I/IItrial of MYO-029 in adult subjects with muscular dystrophy.

OBJECTIVE: Myostatin is an endogenous negative regulator of muscle growth and a novel target for muscle diseases. We conducted a safety trial of a neutralizing antibody to myostatin, MYO-029, in adult muscular dystrophies (Becker muscular dystrophy, facioscapulohumeral dystrophy, and limb-girdle muscular dystrophy). METHODS: This double-blind, placebo-controlled, multinational, randomized study included 116 subjects divided into sequential dose-escalation cohorts, each receiving MYO-029 or placebo (Cohort 1 at 1 mg/kg; Cohort 2 at 3 mg/kg; Cohort 3 at 10 mg/kg; Cohort 4 at 30 mg/kg). Safety and adverse events were assessed by reported signs and symptoms, as well as by physical examinations, laboratory results, echocardiograms, electrocardiograms, and in subjects with facioscapulohumeral dystrophy, funduscopic and audiometry examinations. Biological activity of MYO-029 was assessed through manual muscle testing, quantitative muscle testing, timed function tests, subject-reported outcomes, magnetic resonance imaging studies, dual-energy radiographic absorptiometry studies, and muscle biopsy. RESULTS: MYO-029 had good safety and tolerability with the exception of cutaneous hypersensitivity at the 10 and 30 mg/kg doses. There were no improvements noted in exploratory end points of muscle strength or function, but the study was not powered to look for efficacy. Importantly, bioactivity of MYO-029 was supported by a trend in a limited number of subjects toward increased muscle size using dual-energy radiographic absorptiometry and muscle histology. INTERPRETATION: This trial supports the hypothesis that systemic administration of myostatin inhibitors provides an adequate safety margin for clinical studies. Further evaluation of more potent myostatin inhibitors for stimulating muscle growth in muscular dystrophy should be considered.

Facioscapulohumeral dystrophy.

Facioscapulohumeral dystrophy (FSHD) is the third most common inherited muscular dystrophy after Duchenne dystrophy and myotonic dystrophy. Over the last decade, major advances have occurred in the understanding of the genetics of this disorder. Despite these advances, the exact mechanisms that lead to atrophy and weakness secondary to the genetic defect are still not understood. The purposes of this article are to increase awareness of FSHD among clinicians; to provide an update regarding the genetics, clinical features, natural history, and current management of FSHD; and to discuss opportunities for research.