Effect of Enzyme Replacement Therapy in Patients With Juvenile-onset Pompe Disease
Pompe's Disease Juvenile OnsetPompe disease is known as glycogen storage disease type II, an autosomal recessive disease that results from acid alpha-glucosidase (GAA) deficiency leading to lysosomal glycogen accumulation. Patients with classic infantile form have less than 1% of enzyme activity, which explains severe impairment before one year with rapid death without treatment, while later-onset form shows progressive symptoms later in childhood (juvenile form) or adulthood (adult form). Enzyme replacement therapy (ERT) consists of periodic intravenous infusion of missing GAA produced by the recombinant method. ERT improves significantly the cardiac function and the children's survival in classic infantile form. This therapy has been approved for all patients with Pompe's disease in the United States and the European Union since 2006, but its efficacy was not clear for patients with later-onset form. Recent studies show motor improvement in adult patients, but there is little published data for the juvenile form disease. A separate analysis of juvenile form is justified as patients are still in a developmental stage and show clinical symptoms early in life, may have more severe disease and a different response to ERT. The recommendation is no treatment in the absence of clinical symptoms, but the consensus does not stratify patients into juvenile- or adult-onset form. ERT is an expensive long-term therapy, and its administration every 2 weeks in the hospital is a great limitation for patients. Therefore, an evaluation of the treatment effect in patients with the juvenile form is necessary.
Fat and Sugar Metabolism During Exercise in Patients With Metabolic Myopathy
MetabolismInborn Errors24 moreThis study aims to characterize the pathophysiological mechanisms of 21 different metabolic myopathies. The study will focus on exercise capacity and the metabolic derangement during exercise.
An MRI Study on Muscular Diseases -Pompe Disease and Dystrophia Myotonica-
Glycogen Storage Disease Type 2Dystrophia MyotonicaThe aim of the project is to develop new Magnetic Resonance (MR) imaging techniques for better diagnosis and monitoring of patients with muscular disorders. Muscle quality in patients with Late Onset Pompe Disease (Acid Maltase Deficiency type 2) and in patients with Myotonica Dystrophy will be evaluated, by determining muscle strength in relation to muscle size and muscle strength in relations to fat-muscle ratio.
Prevalence of Pompe's Disease in Respiratory Clinics
Pompe's DiseasePompe's disease is a very rare condition which causes weakness of the respiratory muscles and may therefore cause symptoms of breathlessness or even respiratory failure, requiring the use of a ventilator at night. Recently a treatment for this condition has become available as well as a simple diagnostic test. However, we believe it is possible that there are patients with this condition who are presently undiagnosed attending respiratory clinics. We would like to complete an observational study of patients with respiratory muscle weakness of an unknown cause, who are attending respiratory clinics at two London centres, to determine whether patients attending these services have undiagnosed Pompe's disease.
Effect of Motor Development, Motor Function and Electrophysiologic Findings of IOPD Under ERT
Glycogen Storage Disease Type IITo investigate the motor development, motor function and electrodiagnostics presentation in IOPD under ERT.
Detection of Pompe Disease in Adult Patients With Myopathies of Uncertain Origin or With Asymptomatic...
Pompe DiseaseThe adult onset form can occur between the second and sixth decades of life as a form of proximal myopathy, predominantly in the pelvic girdle area. Sometimes the first symptoms are shortness of breath and diaphragm weakness which herald progressive proximal muscle weakness. The heart and liver are not affected. Serum CK (Creatine Kinase) activity is 2 to 10 times higher than normal. EMG (electromyogram) testing usually reveals a myopathic pattern and muscle biopsy may show vacuoles containing an accumulation of glycogen that is not broken down. Until fairly recently, an assay of acid maltase activity using cultured fibroblasts after biopsy of skin or muscle tissue was required for diagnosis, as leukocytes contain a renal isoenzyme that is not absent in these patients and which can mask the deficit and result in false negatives. In recent years this problem has ben solved by the introduction of acarbose, an inhibitor of renal α-glucosidase; it is also used in the dried blood spot method, which measures acid maltase activity using maltose and acarbose as inhibitors and 4-methylumbelliferyl-D-glucopyranoside as substrate.
Biomarker for Pompe Disease (BioPompe)
Cardiac DiseasesMuscular Weakness5 moreDevelopment of a new MS-based biomarker for the early and sensitive diagnosis of Pompe disease from blood (plasma)
Expanded Access for ATB200/AT2221 for the Treatment of IOPD
Pompe Disease Infantile-OnsetThis is an expanded access program (EAP) for eligible participants designed to provide access to ATB200/AT2221.
Expanded Access for ATB200/AT2221 for the Treatment of Pompe Disease
Pompe DiseaseThis is an expanded access program (EAP) for eligible participants designed to provide access to ATB200/AT2221.
Alglucosidase Alfa Temporary Access Program
Glycogen Storage Disease Type II (GSD-II)Pompe Disease (Late-Onset)2 morePompe disease (also known as glycogen storage disease Type II) is caused by a deficiency of a critical enzyme in the body called acid alpha-glucosidase (GAA). Normally, GAA is used by the body's cells to break down glycogen (a stored form of sugar) within specialized structures called lysosomes. In patients with Pompe disease, an excessive amount of glycogen accumulates and is stored in various tissues, especially heart and skeletal muscle, which prevents their normal function. The objective of this expanded access study is to provide patients with Pompe disease in the United States (US), access to alglucosidase alfa produced from a scaled up manufacturing process for a limited time until production at this scale is approved for commercial use by the Food and Drug Administration.