Subject has been previously treated with Replagal or any other enzyme replacement therapy for Fabry Disease. If the patient has previously been treated with Replagal or another enzyme replacement therapy then they must have been off the therapy for at least 30 days and must have a Day-14 antibody blood sample drawn and that test must be negative for anti-agalsidase alfa IgG and IgE antibodies and not experienced a prior severe infusion reactions with prior enzyme replacement therapy.