A phase Ib/IIa, open-label, multiple ascending-dose trial of domagrozumab in fukutin-related protein limb-girdle muscular dystrophy.

Introduction/aims: In this study we report the results of a phase Ib/IIa, open-label, multiple ascending-dose trial of domagrozumab, a myostatin inhibitor, in patients with fukutin-related protein (FKRP)-associated limb-girdle muscular dystrophy.

Methods: Nineteen patients were enrolled and assigned to one of three dosing arms (5, 20, or 40 mg/kg every 4 weeks). After 32 weeks of treatment, participants receiving the lowest dose were switched to the highest dose (40 mg/kg) for an additional 32 weeks.

Longitudinal functional and imaging outcome measures in FKRP limb-girdle muscular dystrophy.

Background: Pathogenic variants in the FKRP gene cause impaired glycosylation of α-dystroglycan in muscle, producing a limb-girdle muscular dystrophy with cardiomyopathy. Despite advances in understanding the pathophysiology of FKRP-associated myopathies, clinical research in the limb-girdle muscular dystrophies has been limited by the lack of normative biomarker data to gauge disease progression.

Methods: Participants in a phase 2 clinical trial were evaluated over a 4-month, untreated lead-in period to evaluate repeatability and to obtain normative data for timed function tests, strength tests, pulmonary function, and body composition using DEXA and whole-body MRI.

The NIH Toolbox for cognitive surveillance in Duchenne muscular dystrophy.

Objective: We performed a prospective, cross-sectional cognitive assessment in subjects with Duchenne Muscular Dystrophy (DMD) and their biological mothers.

Methods: Thirty subjects with out-of-frame mutations in the dystrophin (DMD) gene, and 25 biological mothers were evaluated using the National Institutes of Health Toolbox Cognition Battery (NIHTB-CB). A parent completed the Behavior Rating Inventory of Executive Functioning (BRIEF), a standardized rating scale of executive functioning, for their child.

Are dopamine receptor and transporter changes in Rett syndrome reflected in Mecp2-deficient mice?

We tested the claim that the dopaminergic dysfunction of Rett Syndrome (RTT) also occurs in Mecp2-deficient mice that serve as a model of the syndrome. We used positron emission tomography (PET) to image dopamine D receptors (DR) and transporters (DAT) in women with RTT and in Mecp2-deficient mice, and DR and DR density was measured in postmortem human tissue by autoradiography. Results showed 1) significantly reduced DR density in the striatum of women with RTT compared to control subjects.

Randomized open-label trial of dextromethorphan in Rett syndrome.

Objective: To determine safety and perform a preliminary assessment of dose-dependent efficacy of dextromethorphan in normalizing electrographic spikes, clinical seizures, and behavioral and cognitive functions in girls with Rett syndrome.

Methods: We used a prospective randomized, open-label trial in fast metabolizers of dextromethorphan to examine the effect of dextromethorphan on core clinical features of Rett syndrome. Interictal spike activity and clinical seizures were determined using EEG and parent reporting.