ABSTRACT
INTRODUCTION: Anderson-Fabry disease (AFD) is a multiorgan X-linked lysosomal storage disease that particularly affects the heart, kidneys, and cerebrovascular system. Current treatment is with enzyme replacement therapy (ERT), using either beta-galactosidase ('Fabrazyme') or alpha-galactosidase ('Replagal'). From June 2009, it was recommended that patients switch to alpha-galactosidase due to a manufacturing shortage of beta-galactosidase. This study assesses the effect of switching to alpha-galactosidase on clinical outcomes in patients with AFD previously treated with beta-galactosidase. PATIENTS AND METHODS: Ten patients (seven male, three female) with genetically confirmed AFD and at least 48 months continuous data collected during treatment with beta-galactosidase 1 mg/kg every other week, were switched to alpha-galactosidase 0.2 mg/kg every other week for at least 20 months, with prospective clinical evaluations performed every 6 months. Pre-switch data was collected retrospectively from patient charts. Cardiac functional parameters were assessed using magnetic resonance imaging. RESULTS: Results showed that renal function generally remained stable after the switch. Cardiac mass had already decreased significantly (p < 0.05 vs pre-ERT) after introduction of beta-galactosidase and remained unchanged after switching to alpha-galactosidase. Symptoms of pain and health status scores did not deteriorate during alpha-galactosidase therapy. Adverse events were mostly mild and infusion -related. DISCUSSION: In conclusion, switching to alpha-galactosidse was generally well tolerated and associated with stable clinical status and preservation of both renal and cardiac function.