The long-term effect of initiating ERT in childhood is unknown. Prospective studies of Children with Fabry disease on 0.2 mg/kg agalsidase alfa every other week were performed. The patients were 7-17 years of age at initial study enrollment. The first open-label protocol was TKT023, a 6 months study (August 12, 2002-October 20, 2004) that was followed by an extension study TKT029 (June 10, 2004-June 15, 2011; ClinicalTrials.gov identifier NCT00084084). Since completing TKT029, all US patients were switched to commercial agalsidase beta. Therefore, these patients have now been treated for about 15 years.This study involves a one-visit follow up on these patients using the same protocol-driven studies as were used in TKT029. The long-term follow up data gathered will consist of a rare description of the disease profile in patients who were treated with ERT since childhood.
