Anderson-Fabry disease (AFD) is a multiorgan X-linked
lysosomal storage disease that particularly affects the heart, kidneys, and cerebrovascular system. Current treatment is
enzyme replacement therapy (ERT) with
agalsidase beta (
Fabrazyme(®), Genzyme Corporation, Cambridge, MA, USA) or
agalsidase alfa (
Replagal(®), Shire Human Genetic Therapies AB, Lund, Sweden). It was recommended that patients switch to
agalsidase alfa due to a manufacturing shortage of
agalsidase beta beginning in June 2009. This study assessed the effect of switching to
agalsidase alfa on clinical outcomes in patients with AFD previously treated with
agalsidase beta. Ten patients (seven male, three female) with genetically confirmed AFD and at least 48 months' continuous data collected during treatment with
agalsidase beta 1 mg/kg every other week were switched to
agalsidase alfa 0.2 mg/kg every other week for at least 20 months, with prospective clinical evaluations every 6 months. Pre-switch data was collected retrospectively from patient charts. Cardiac functional parameters were assessed using magnetic resonance imaging. Results showed that renal function was normal (estimated glomerular filtration rate ≥90 mL/min/1.73 m(2)) in 8 of 10 patients prior to
agalsidase alfa and generally remained stable after the switch. Cardiac mass decreased significantly (p < 0.05 vs pre-ERT) after
agalsidase beta and remained unchanged after switching to
agalsidase alfa. Symptoms of
pain and health status scores did not deteriorate during
agalsidase alfa therapy. Adverse events were mostly mild and infusion related. In conclusion, switching to
agalsidase alfa was relatively well tolerated and associated with stable clinical status and preserved renal and cardiac function.