Replagal Enzyme Replacement Therapy for Children With Fabry Disease

Inclusion Criteria: 1a. For Cohort 1 (both phases): \- Patients must have completed all study requirements and assessments for Study TKT023 less than 30 (+/-7) days prior to enrolling in Study TKT029 and must have no safety or medical issues that contraindicate participation. OR 1b. For Cohort 2: * The patient is between 7 and 17 years of age at the time of informed consent, inclusive. * The patient must be ERT-naive. * The patient is a hemizygous male with Fabry disease as confirmed by a deficiency of alpha-galactosidase A activity measured in serum, leukocytes, or fibroblasts. Male patients who do not already have a documented deficiency of alpha-galactosidase A activity will provide a blood sample during screening for determination of alpha-galactosidase A activity level in their serum. OR \- The patient is a heterozygous female or hemizygous male with Fabry disease as confirmed by a mutation of the alpha-galactosidase A gene. Patients who do not already have a documented mutation of the alpha-galactosidase A gene will provide a blood sample during screening for genotyping. 2\. Adequate general health (as determined by the Investigators) to undergo the specified phlebotomy regimen and protocol-related procedures and no safety or medical contraindications for participation. 3\. The minor child must assent to participate in the protocol and the parent(s) or legally authorized guardian(s) must have voluntarily signed an Institutional Review Board/Independent Ethics C…