D. Escolar

THE COOPERATIVE INTERNATIONAL NEUROMUSCULAR RESEARCH GROUP DUCHENNE NATURAL HISTORY STUDY: GLUCOCORTICOID TREATMENT PRESERVES CLINICALLY MEANINGFUL FUNCTIONAL MILESTONES AND REDUCES RATE OF DISEASE PROGRESSION AS MEASURED BY MANUAL MUSCLE TESTING AND OTHER COMMONLY USED CLINICAL TRIAL OUTCOME MEASURES

Introduction: Glucocorticoid (GC) therapy in Duchenne muscular dystrophy (DMD) has altered disease progression, necessitating contemporary natural history studies. Methods: The Cooperative Neuromuscular Research Group (CINRG) DMD Natural History Study (DMD‐NHS) enrolled 340 DMD males, ages 2–28 years. A comprehensive battery of measures was obtained. Results: A novel composite functional “milestone” scale scale showed clinically meaningful mobility and upper limb abilities were significantly preserved in GC‐treated adolescents/young adults. Manual muscle test (MMT)‐based calculations of global strength showed that those patients <10 years of age treated with steroids declined by 0.4±0.39 MMT unit/year, compared with −0.4±0.39 MMT unit/year in historical steroid‐naive subjects. Pulmonary function tests (PFTs) were relatively preserved in steroid‐treated adolescents. The linearity and magnitude of decline in measures were affected by maturational changes and functional status. Conclusions: In DMD, long‐term use of GCs showed reduced strength loss and preserved functional capabilities and PFTs compared with previous natural history studies performed prior to the widespread use of GC therapy. Muscle Nerve, 2013

The cooperative international neuromuscular research group duchenne natural history study—a longitudinal investigation in the era of glucocorticoid therapy: Design of protocol and the methods used

Contemporary natural history data in Duchenne muscular dystrophy (DMD) is needed to assess care recommendations and aid in planning future trials.

Myostatin inhibitor ACE‐031 treatment of ambulatory boys with Duchenne muscular dystrophy: Results of a randomized, placebo‐controlled clinical trial

Introduction: ACE‐031 is a fusion protein of activin receptor type IIB and IgG1‐Fc, which binds myostatin and related ligands. It aims to disrupt the inhibitory effect on muscle development and provide potential therapy for myopathies like Duchenne muscular dystrophy (DMD). Methods: ACE‐031 was administered subcutaneously every 2–4 weeks to DMD boys in a randomized, double‐blind, placebo‐controlled, ascending‐dose trial. The primary objective was safety evaluation. Secondary objectives included characterization of pharmacokinetics and pharmacodynamics. Results: ACE‐031 was not associated with serious or severe adverse events. The study was stopped after the second dosing regimen due to potential safety concerns of epistaxis and telangiectasias. A trend for maintenance of the 6‐minute walk test (6MWT) distance in the ACE‐031 groups compared with a decline in the placebo group (not statistically significant) was noted, as was a trend for increased lean body mass and bone mineral density (BMD) and reduced fat mass. Conclusion: ACE‐031 use demonstrated trends for pharmacodynamic effects on lean mass, fat mass, BMD, and 6MWT. Non–muscle‐related adverse events contributed to the decision to discontinue the study. Myostatin inhibition is a promising therapeutic approach for DMD. Muscle Nerve 55: 458–464, 2017

Worsening of multifocal motor neuropathy during pregnancy

Abstract—Three women with multifocal motor neuropathy (MMN) were treated during pregnancy. Compared with their pregestation strength, the women became weaker in previously involved muscles and showed new weakness in previously unaffected muscles. All were treated with IV immunoglobulin during pregnancy and improved in strength. After pregnancy, strength in all patients returned to the prepregnancy state. The authors conclude that pregnancy may worsen MMN.

Barriers and facilitators to clinical trial participation among parents of children with pediatric neuromuscular disorders

Background/aims: Pediatric rare disease presents a challenging situation of high unmet need and a limited pool of potential clinical trial participants. Understanding perspectives of parents of children who have not participated in trials may facilitate approaches to optimize participation rates. The objective of this study was to explore factors associated with parental interest in enrolling children with pediatric neuromuscular disorders in clinical trials. Methods: Parents of individuals with Duchenne or Becker muscular dystrophy and spinal muscular atrophy were recruited through advocacy organizations, a registry, and clinics. These parents (N = 203) completed a questionnaire including assessments of barriers and facilitators to clinical trial participation, parents’ interest in trial participation, and their perceptions of others’ views about participation in a clinical trial. Results: Trial interest in participating parents was high (64% combined group). The most highly endorsed barrier to participation was the possibility of receiving placebo, followed by not having enough information on risks and trial procedures. Compared to parents of children with Duchenne or Becker muscular dystrophy, parents of children with spinal muscular atrophy endorsed significantly more information and knowledge barriers. The greatest facilitators of participation were (1) confidence in improving disease understanding and (2) guarantee to receive the treatment after a successful trial. A logistic regression model, χ2 (4, n = 188) = 80.64, p < .001, indicated that higher perceived barriers and more frequent trial communication by the provider were associated with lower interest, while positive trial perceptions by the child’s providers and concordance in trial perceptions among those close to the decision-maker were associated with higher interest. Conclusion: We found high parental interest in pediatric neuromuscular trials that was tempered by concerns about the potential for randomization to a placebo arm. Participants perceived that their trial participation would be facilitated by additional education and guidance from their clinicians. Yet, intentions were negatively associated with frequency of provider communication, perhaps reflecting waning parental interest with a greater understanding of limitations in trial access, increased sophistication in their understanding of trial design, and appreciation of potential burden. To support parents’ informed decisions, it is important to educate them to evaluate the quality of research, as well as providing lay information explaining the use of placebo, trial processes, and potential barriers to long-term drug access. Our findings should inform the development of targeted educational content, clinician training, and decision support tools.

P.11.14 Phase 1b single and multiple ascending dose study to evaluate the safety, tolerability and pharmacokinetics of HT-100 in DMD

In DMD, chronic inflammation leads to endomysial fibrosis, resulting in abnormal force transmission, decreased muscle perfusion and impairment of muscle regeneration. This pathology is directly related to progressive deterioration in motor, respiratory and cardiac function. Halofuginone hydrobromide is an orally-delivered anti-fibrotic and anti-inflammatory agent with effects on molecular, pathology, and functional phenotypes of dystrophic mice, making it a promising candidate for clinical development in DMD. Earlier formulations have been associated with tolerability issues at higher doses which limited the total daily dose that could be administered. Halo Therapeutics has developed HT-100, a delayed-release formulation, allowing for delivery of potentially larger doses with enhanced tolerability. This new formulation has undergone initial testing in animals (canines) where it was well tolerated and resulted in similar systemic exposure to the original formulation. While these results are encouraging, the tolerability and pharmacokinetics (PK) profile of the new formulation needs to be confirmed in the DMD patient population. The current trial is designed to provide initial safety, tolerability, and PK data in DMD participants with a broad spectrum of the disease in order to provide information regarding safety and tolerability and to inform dose selection for a future larger study to be conducted in a more homogenous DMD population. After completion of the Phase Ib ascending dose phase of this study, participants will be eligible to enroll in a 6-month, open-label extension study. Background and supporting data on HT-100 will be presented as well as the Phase Ib and extension study clinical protocols.