The main goal of this study is to assess the pharmacodynamic effects of different or more frequent doses of Replagal compared to the standard dosing regimen. Replagal is a genetically engineered form of alpha-Galactosidase A, an enzyme that normally breaks down a fatty substance called globotriaosylceramide (Gb(3)). In patients with Fabry disease, GB(3) does not function properly and therefore builds up causing problems with the kidneys, heart, nerves, and blood vessels.