Inclusion Criteria:

• Patients must provide written informed consent
• Patients must be at least 16 years old
• Patients must have a current diagnosis of Fabry disease
• Patients may not have received enzyme replacement therapy as a treatment for Fabry disease
• Patients must have a documented plasma a-galactosidase A (aGAL) activity of < 1.5 nmol/hr/mL or a documented leukocyte aGAL activity of < 4 nmol/hr/mg
• Patients must have one or more of the following: a serum creatinine measurement of 1.2 to 3 mg/dL (106.1 to 265 umol/L) OR estimated creatinine clearance < 80 mL/min only if the patient's serum creatinine measurement is < 1.2 mg/dL
• Female patients of childbearing potential must have a negative pregnancy test prior to each dosing and all female patients must use a medically accepted form of contraception

Exclusion Criteria:

• Patient has undergone or is currently scheduled for kidney transplantation or is currently on dialysis
• Patient has acute renal failure
• Patient has participated in a study employing an investigational drug within 30 days of study entry
• Patient has diabetes mellitus or presence of confounding renal disease
• Patient has a history of TIA or ischemic stroke within 3 months of study entry documented by mild-to-moderate neurological deficit
• Patient has critical coronary disease
• Patient has congestive heart failure
• Patient has severe residual neurological deficit that will confound the detection of new events as determined by an attending neurologist and/or Principal Investigator
• Patient is unwilling to comply with the requirements of the protocol or the patient has a medical condition, serious intercurrent illness, or extenuating circumstances that would significantly decrease study compliance, including prescribed follow-up