rhGAA in Patients With Infantile-onset Glycogen Storage Disease-II (Pompe Disease)

Inclusion Criteria: * The patient or the patient's legal guardian(s) must provide written informed consent prior to any study-related procedures being performed * The patient must have a clinical diagnosis of infantile GSD-II as defined by: (a) the patient has/had documented (in a medical record) onset of symptoms compatible with GSD-II by 12 months of age; (b) the patient has documented GAA deficiency as illustrated by an endogenous GAA activity less than or equal to 2% of the mean of the normal range as assessed in cultured skin fibroblasts; AND (c) the patient has a Left Ventricular Mass Index greater than 2 standard deviations above the mean for age * The patient is greater than 6 months old and less than or equal to 36 months old at the time of the first dose of rhGAA * The patient and his/her legal guardian(s) must have the ability to comply with the clinical protocol Exclusion Criteria: * Signs and symptoms of cardiac failure and an ejection fraction less than 40% * Major congenital abnormality * Clinically significant organic disease (with the exception of symptoms relating to GSD-II), including clinically significant cardiovascular, hepatic, pulmonary, neurologic, or renal disease, or other medical condition, serious intercurrent illness, or extenuating circumstance that, in the opinion of the Investigator, would preclude participation in the trial or potentially decrease survival * Use of any investigational product within 30 days prior to study enrollment * Received enzyme replacement therapy with GAA from any source