Enzyme replacement therapy with alglucosidase alfa in 44 patients with late-onset glycogen storage disease type 2: 12-month results of an observational clinical trial.
Author(s): Strothotte S, Strigl-Pill N, Grunert B, Kornblum C, Eger K, Wessig C, Deschauer M, Breunig F, Glocker FX, Vielhaber S, Brejova A, Hilz M, Reiners K, Muller-Felber W, Mengel E, Spranger M, Schoser B
Affiliation(s): Department of Neurology, Friedrich Baur Institute, Ludwig Maximilian University Munich, Munich, Germany.
Publication date & source: 2010-01, J Neurol., 257(1):91-7. Epub 2009 Aug 1.
Publication type: Clinical Trial
Late-onset glycogen storage disease type 2 (GSD2)/Pompe disease is a progressive multi-system disease evoked by a deficiency of lysosomal acid alpha-glucosidase (GAA) activity. GSD2 is characterized by respiratory and skeletal muscle weakness and atrophy, resulting in functional disability and reduced life span. Since 2006 alglucosidase alfa has been licensed as a treatment in all types of GSD2/Pompe disease. We here present an open-label, investigator-initiated observational study of alglucosidase alfa enzyme replacement therapy (ERT) in 44 late-onset GSD2 patients with various stages of disease severity. Alglucosidase alfa was given i.v. at the standard dose of 20 mg/kg every other week. Assessments included serial arm function tests (AFT), Walton Gardner Medwin scale (WGMS), timed 10-m walk tests, four-stair climb tests, modified Gowers' maneuvers, 6-min walk tests, MRC sum score, forced vital capacities (FVC), creatine kinase (CK) levels and SF-36 self-reporting questionnaires. All tests were performed at baseline and every 3 months for 12 months of ERT. We found significant changes from baseline in the modified Gowers' test, the CK levels and the 6-min walk test (341 +/- 149.49 m, median 342.25 m at baseline; 393 +/- 156.98 m; median 411.50 m at endpoint; p = 0.026), while all other tests were unchanged. ERT over 12 months revealed minor allergic reactions in 10% of the patients. No serious adverse events occurred. None of the patients died or required de novo ventilation. Our clinical outcome data imply stabilization of neuromuscular deficits over 1 year with mild functional improvement.