Repeated intravenous cardiosphere-derived cell therapy in late-stage Duchenne muscular dystrophy (HOPE-2): a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial.

BACKGROUND: Cardiosphere-derived cells (CDCs) ameliorate skeletal and cardiac muscle deterioration in experimental models of Duchenne muscular dystrophy. The HOPE-2 trial examined the safety and efficacy of sequential intravenous infusions of human allogeneic CDCs in late-stage Duchenne muscular dystrophy. METHODS: In this multicentre, randomised, double-blind, placebo-controlled, phase 2 trial, patients with Duchenne muscular dystrophy, aged 10 years or older with moderate upper limb impairment, were enrolled at seven centres in the USA. Patients were randomly assigned (1:1) using stratified permuted blocks to receive CAP-1002 (1·5 × 108 CDCs) or placebo intravenously every 3 months for a total of four infusions. Clinicians, caregivers, patients, and clinical operations personnel were fully masked to treatment groups. The primary outcome was the change in mid-level elbow Performance of Upper Limb version 1.2 (PUL 1.2) score at 12 months, assessed in the intention-to-treat population. Safety was assessed in all individuals who received an investigational product. This trial is registered with ClinicalTrials.gov, NCT03406780. FINDINGS: Between March 1, 2018, and March 31, 2020, 26 male patients with Duchenne muscular dystrophy were enrolled, of whom eight were randomly assigned to the CAP-1002 group and 12 to the placebo group (six were not randomised due to screening failure). In patients who had a post-treatment PUL 1.2 assessment (eight in the CAP-1002 group and 11 in the placebo group), the mean 12-month change from baseline in mid-level elbow PUL1.2 favoured CAP-1002 over placebo (percentile difference 36·2, 95% CI 12·7-59·7; difference of 2·6 points; p=0·014). Infusion-related hypersensitivity reactions without long-term sequelae were observed in three patients, with one patient discontinuing therapy due to a severe allergic reaction. No other major adverse reactions were noted, and no deaths occurred. INTERPRETATION: CAP-1002 cell therapy appears to be safe and effective in reducing deterioration of upper limb function in patients with late-stage Duchenne muscular dystrophy. Various measures of cardiac function and structure were also improved in the CAP-1002 group compared with the placebo group. Longer-term extension studies are needed to confirm the therapeutic durability and safety of CAP-1002 beyond 12 months for the treatment of skeletal myopathy and cardiomyopathy in Duchenne muscular dystrophy. FUNDING: Capricor Therapeutics.

Development of a Clinical Global Impression of Change (CGI-C) and a Caregiver Global Impression of Change (CaGI-C) measure for ambulant individuals with Duchenne muscular dystrophy.

BACKGROUND: In clinical trials for rare diseases, such as Duchenne muscular dystrophy, clinical outcome assessments (COA) used to assess treatment benefit are often generic and may not be sensitive enough to detect change in specific patient populations. Thus, there is a need for disease specific COAs that track meaningful change among individuals. When developing such measures, input from clinicians, caregivers and patients is critical for assessing clinically relevant concepts and ensuring validity of the measure. METHOD: The aim of this study was to develop two Duchenne-specific global impression items for use in clinical trials. The development of the Duchenne Clinical Global Impression of Change (CGI-C) and Caregiver Global Impression of Change (CaGI-C) was informed by findings from concept elicitation (CE) interviews with clinicians, caregivers and individuals with Duchenne. Through cognitive debriefing (CD) interviews, clinicians and caregivers evaluated draft CGI-C and CaGI-C items to ensure relevance and understanding of the items and instructions. Suggestions made during the CD interviews were incorporated into the finalized CGI-C and CaGI-C measures. RESULTS: The symptoms most frequently reported by clinicians, caregivers and individuals with Duchenne were muscle weakness, fatigue, cardiac difficulties and pain. Regarding physical functioning, all three populations noted that small changes in functional ability were meaningful, particularly when independence was impacted. Caregivers and clinicians reported that changes in speed, endurance and quality of movement were important, as was improvement in the ability of individuals to keep up with their peers. A change in the ability to complete everyday activities was also significant to families. These results were used to create two global impression of change items and instruction documents for use by clinicians (CGI-C) and caregivers (CaGI-C). Overall, both items were well understood by participants. The descriptions and examples developed from the CE interviews were reported to be relevant and appropriate for illustrating different levels of meaningful change in patients with Duchenne. Modifications were made based on caregiver and clinician CD feedback . CONCLUSIONS: As part of a holistic measurement strategy, such COA can be incorporated into the clinical trial setting to assess global changes in relevant symptoms and functional impacts associated with Duchenne.

Delays in diagnosis of Duchenne muscular dystrophy: An evaluation of genotypic and sociodemographic factors.

INTRODUCTION: In this study we investigate associations between genotypic and sociodemographic factors and the age of diagnosis of Duchenne muscular dystrophy (DMD). METHODS: Data were collected from the Duchenne Registry from 2007 to 2019, and then used to assess the impact genotype, race/ethnicity, neighborhood poverty levels, and other sociodemographics factors have on the age of diagnosis of DMD patients without a known family history, using univariate and multivariable linear regression. RESULTS: The mean age of diagnosis was 4.43 years. Non-Caucasian patients and patients from high-poverty neighborhoods were older at diagnosis (P < .01). Increased year of birth was associated with decreasing age of diagnosis (P < .001). Specific genetic mutation subtypes were associated with later ages of symptom onset and diagnosis (P = .005). DISCUSSION: After adjusting for genotype and year of birth, the average age of diagnosis was significantly later for traditionally at-risk patients.

Large-scale serum protein biomarker discovery in Duchenne muscular dystrophy.

Serum biomarkers in Duchenne muscular dystrophy (DMD) may provide deeper insights into disease pathogenesis, suggest new therapeutic approaches, serve as acute read-outs of drug effects, and be useful as surrogate outcome measures to predict later clinical benefit. In this study a large-scale biomarker discovery was performed on serum samples from patients with DMD and age-matched healthy volunteers using a modified aptamer-based proteomics technology. Levels of 1,125 proteins were quantified in serum samples from two independent DMD cohorts: cohort 1 (The Parent Project Muscular Dystrophy-Cincinnati Children's Hospital Medical Center), 42 patients with DMD and 28 age-matched normal volunteers; and cohort 2 (The Cooperative International Neuromuscular Research Group, Duchenne Natural History Study), 51 patients with DMD and 17 age-matched normal volunteers. Forty-four proteins showed significant differences that were consistent in both cohorts when comparing DMD patients and healthy volunteers at a 1% false-discovery rate, a large number of significant protein changes for such a small study. These biomarkers can be classified by known cellular processes and by age-dependent changes in protein concentration. Our findings demonstrate both the utility of this unbiased biomarker discovery approach and suggest potential new diagnostic and therapeutic avenues for ameliorating the burden of DMD and, we hope, other rare and devastating diseases.

Draft Guidance for Industry Duchenne Muscular Dystrophy, Becker Muscular Dystrophy, and Related Dystrophinopathies - Developing Potential Treatments for the Entire Spectrum of Disease.

Background: Duchenne muscular dystrophy (DMD) and related dystrophinopathies are neuromuscular conditions with great unmet medical needs that require the development of effective medical treatments. Objective: To aid sponsors in clinical development of drugs and therapeutic biological products for treating DMD across the disease spectrum by integrating advancements, patient registries, natural history studies, and more into a comprehensive guidance. Methods: This guidance emerged from collaboration between the FDA, the Duchenne community, and industry stakeholders. It entailed a structured approach, involving multiple committees and boards. From its inception in 2014, the guidance underwent revisions incorporating insights from gene therapy studies, cardiac function research, and innovative clinical trial designs. Results: The guidance provides a deeper understanding of DMD and its variants, focusing on patient engagement, diagnostic criteria, natural history, biomarkers, and clinical trials. It underscores patient-focused drug development, the significance of dystrophin as a biomarker, and the pivotal role of magnetic resonance imaging in assessing disease progression. Additionally, the guidance addresses cardiomyopathy's prominence in DMD and the burgeoning field of gene therapy. Conclusions: The updated guidance offers a comprehensive understanding of DMD, emphasizing patient-centric approaches, innovative trial designs, and the importance of biomarkers. The focus on cardiomyopathy and gene therapy signifies the evolving realm of DMD research. It acts as a crucial roadmap for sponsors, potentially leading to improved treatments for DMD.

Improving the Translational Medicine Process: Moving Patients From "End-Users" to "Engaged Collaborators".

Translational medicine works through the definition of unmet medical needs, their understanding and final resolution. In this complex and multi-disciplinary process patients have always been regarded as "end-users" or no more than "data provider." Considering that the translational practice is nowadays highly inefficient (i.e., large intellectual and economical resources are wasted with limited impact on people health) here we propose to reverse the process: start from patients, engage them, and keep them at the center. A new partnership needs to be formed between the patients and the health care professionals, as well as the treating physicians, to make the most out of the current "health resources." New patient-centric approaches are emerging but they remain isolated phenomena often difficult to implement. Here-with this perspective-we aim at thinking differently and learning from new experiences. We will provide some successful examples of change, and we will discuss new approaches to create a radical change in the way translational medicine is managed and how this would significantly impact people health and health care systems.

A phase 3 randomized placebo-controlled trial of tadalafil for Duchenne muscular dystrophy.

OBJECTIVE: To conduct a randomized trial to test the primary hypothesis that once-daily tadalafil, administered orally for 48 weeks, lessens the decline in ambulatory ability in boys with Duchenne muscular dystrophy (DMD). METHODS: Three hundred thirty-one participants with DMD 7 to 14 years of age taking glucocorticoids were randomized to tadalafil 0.3 mg·kg-1·d-1, tadalafil 0.6 mg·kg-1·d-1, or placebo. The primary efficacy measure was 6-minute walk distance (6MWD) after 48 weeks. Secondary efficacy measures included North Star Ambulatory Assessment and timed function tests. Performance of Upper Limb (PUL) was a prespecified exploratory outcome. RESULTS: Tadalafil had no effect on the primary outcome: 48-week declines in 6MWD were 51.0 ± 9.3 m with placebo, 64.7 ± 9.8 m with low-dose tadalafil (p = 0.307 vs placebo), and 59.1 ± 9.4 m with high-dose tadalafil (p = 0.538 vs placebo). Tadalafil also had no effect on secondary outcomes. In boys >10 years of age, total PUL score and shoulder subscore declined less with low-dose tadalafil than placebo. Adverse events were consistent with the known safety profile of tadalafil and the DMD disease state. CONCLUSIONS: Tadalafil did not lessen the decline in ambulatory ability in boys with DMD. Further studies should be considered to confirm the hypothesis-generating upper limb data and to determine whether ambulatory decline can be slowed by initiation of tadalafil before 7 years of age. CLINICALTRIALSGOV IDENTIFIER: NCT01865084. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that tadalafil does not slow ambulatory decline in 7- to 14-year-old boys with Duchenne muscular dystrophy.

Duchenne Regulatory Science Consortium Meeting on Disease Progression Modeling for Duchenne Muscular Dystrophy.

INTRODUCTION: The Duchenne Regulatory Science Consortium (D-RSC) was established to develop tools to accelerate drug development for DMD.  The resulting tools are anticipated to meet validity requirements outlined by qualification/endorsement pathways at both the U.S. Food and Drug Administration (FDA) and European Medicines Administration (EMA), and will be made available to the drug development community. The initial goals of the consortium include the development of a disease progression model, with the goal of creating a model that would be used to forecast changes in clinically meaningful endpoints, which would inform clinical trial protocol development and data analysis.  Methods: In April of 2016 the consortium and other experts met to formulate plans for the development of the model.  Conclusions: Here we report the results of the meeting, and discussion as to the form of the model that we plan to move forward to develop, after input from the regulatory authorities.

Mothers' psychological adaptation to Duchenne/Becker muscular dystrophy.

Duchenne and Becker muscular dystrophy (DBMD) cause significant emotional and care-related burden on caregivers, but no studies have evaluated predictors of positive caregiver outcomes, including disorder-specific psychological adaptation. Using a community-engaged approach focused on supporting mothers in positive aspects of caregiving, this prospective study aims to assess (i) the association between child's baseline functional status and mothers' illness perceptions, resilience, and coping self-efficacy; and (ii) predictors of mothers' psychological adaptation to caring for a child with DBMD. Biological mothers with at least one living child with DBMD completed a baseline survey (n=205) with 1-year (n=147) and 2-year (n=144) follow-up surveys. Worse child's baseline function was associated not only with increased caregiver burden and reduced maternal resilience, but also with perception of positive disease impact on the family. At two follow-ups, increased psychological adaptation to DBMD was predicted by resilience (ß=0.264, P=0.001) and perceived positive impact (ß=0.310, P<0.001), controlling for mother's age (ß=-0.305, P<0.001) and income (ß=-0.088, P=0.245). Child's functional status and caregiver burden of DBMD did not predict DBMD-specific adaptation. Though clinicians caring for families with DBMD should anticipate increased caregiver burden as the disorder progresses, interventions focused on caregiver burden are not expected to influence mothers' psychosocial adaptation. Efforts to improve mothers' well-being should focus on fostering mothers' resilience and enhancing perceptions of positive disease impact (benefit finding). Results suggest that psychosocial interventions can highlight strengths and well-being rather than burden and deficit.

Stakeholder cooperation to overcome challenges in orphan medicine development: the example of Duchenne muscular dystrophy.

Duchenne muscular dystrophy is a rare, progressive, muscle-wasting disease leading to severe disability and premature death. Treatment is currently symptomatic, but several experimental therapies are in development. Implemented care standards, validated outcome measures correlating with clinical benefit, and comprehensive information about the natural history of the disease are essential for regulatory approval of any treatment. However, for Duchenne muscular dystrophy and other rare diseases, these requirements are not always in place when potential therapies enter the clinical trial phase. A cooperative effort of stakeholders in Duchenne muscular dystrophy-including representatives from patients' groups, academia, industry, and regulatory agencies-is aimed at addressing this shortfall by identifying strategies to overcome challenges, developing the tools needed, and collecting relevant data. An open and constructive dialogue among European stakeholders has positively affected development of treatments for Duchenne muscular dystrophy; this approach could serve as a paradigm for development of treatments for rare diseases in general.

Imperatives for DUCHENNE MD: a Simplified Guide to Comprehensive Care for Duchenne Muscular Dystrophy.

Duchenne muscular dystrophy (DMD) is a progressive, life-limiting muscle-wasting disease. Although no curative treatment is yet available, comprehensive multidisciplinary care has increased life expectancy significantly in recent decades. An international consensus care publication in 2010 outlined best-practice care, which includes corticosteroid treatment, respiratory, cardiac, orthopedic and rehabilitative interventions to address disease manifestations. While disease specialists are largely aware of these care standards, local physicians responsible for the day-to-day care of patients and families may be less familiar. To facilitate optimal care, a one-page document has been generated from published care recommendations, summarizing the key elements of comprehensive care for people living with DMD ("Imperatives for Duchenne muscular dystrophy). This document was developed through an international collaboration between Parent Project Muscular Dystrophy (PPMD), United Parent Projects Muscular Dystrophy (UPPMD) and TREAT-NMD.

Recommendations for the development of rare disease drugs using the accelerated approval pathway and for qualifying biomarkers as primary endpoints.

For rare serious and life-threatening disorders, there is a tremendous challenge of transforming scientific discoveries into new drug treatments. This challenge has been recognized by all stakeholders who endorse the need for flexibility in the regulatory review process for novel therapeutics to treat rare diseases. In the United States, the best expression of this flexibility was the creation of the Accelerated Approval (AA) pathway. The AA pathway is critically important for the development of treatments for diseases with high unmet medical need and has been used extensively for drugs used to treat cancer and infectious diseases like HIV.In 2012, the AA provisions were amended to enhance the application of the AA pathway to expedite the development of drugs for rare disorders under the Food and Drug Administration Safety and Innovation Act (FDASIA). FDASIA, among many provisions, requires the development of a more relevant FDA guidance on the types of evidence that may be acceptable in support of using a novel surrogate endpoint. The application of AA to rare diseases requires more predictability to drive greater access to appropriate use of AA for more rare disease treatments that might not be developed otherwise.This white paper proposes a scientific framework for assessing biomarker endpoints to enhance the development of novel therapeutics for rare and devastating diseases currently without adequate treatment and is based on the opinions of experts in drug development and rare disease patient groups. Specific recommendations include: 1) Establishing regulatory rationale for increased AA access in rare disease programs; 2) Implementing a Biomarker Qualification Request Process to provide the opportunity for an early determination of biomarker acceptance; and 3) A proposed scientific framework for qualifying biomarkers as primary endpoints. The paper's final section highlights case studies of successful examples that have incorporated biomarker endpoints into FDA approvals for rare disease therapies. The focus of this paper is on the situation in the Unites States, but the recommendations are reasonably applicable to any jurisdiction.

How a patient advocacy group developed the first proposed draft guidance document for industry for submission to the U.S. Food and Drug Administration.

Among the challenges confronting patients with rare diseases is a dearth of treatment options. The development of safe and effective new therapies is hampered by challenges associated with conducting clinical trials in small populations. In this article, we describe how the Duchenne muscular dystrophy community-led by Parent Project Muscular Dystrophy-created a proposed draft guidance document for industry for submission to the U.S. Food and Drug Administration. This unprecedented undertaking involved a broad coalition of more than 80 stakeholders collaborating across nine time zones to produce a document in only 6 months. We hope that other rare disease communities and advocacy organizations can use our experience as a model for developing their own draft guidance documents.

Quality assurance for Duchenne and Becker muscular dystrophy genetic testing: development of a genomic DNA reference material panel.

Duchenne and Becker muscular dystrophies (DMD/BMD) are allelic X-linked recessive disorders that affect approximately 1 in 3500 and 1 in 20,000 male individuals, respectively. Approximately 65% of patients with DMD have deletions, 7% to 10% have duplications, and 25% to 30% have point mutations in one or more of the 79 exons of the dystrophin gene. Most clinical genetics laboratories test for deletions, and some use technologies that can detect smaller mutations and duplications. Reference and quality control materials for DMD/BMD diagnostic and carrier genetic testing are not commercially available. To help address this need, the Centers for Disease Control and Prevention-based Genetic Testing Reference Material Coordination Program, in collaboration with members of the genetic testing and the DMD/BMD patient communities and the Coriell Cell Repositories, have characterized new and existing cell lines to create a comprehensive DMD/BMD reference material panel. Samples from 31 Coriell DMD cell lines from male probands and female carriers were analyzed using the Affymetrix SNP Array 6.0 and Multiplex Ligation-Dependent Probe Amplification (MRC-Holland BV, Amsterdam, the Netherlands), a multiplex PCR assay, and DNA sequence analysis. Identified were 16 cell lines with deletions, 9 with duplications, and 4 with point mutations distributed throughout the dystrophin gene. There were no discordant results within assay limitations. These samples are publicly available from Coriell Institute for Medical Research (Camden, NJ) and can be used for quality assurance, proficiency testing, test development, and research, and should help improve the accuracy of DMD testing.