Re-administration of Intramuscular AAV9 in Patients With Late-Onset Pompe Disease

The dose selected for this study is a fixed dose of 4.6 x 10\^13 vg per TA muscle (range of 7.64 x 10\^11 vg/gm to 4.6 x 10\^11 vg/gm based on TA weight).

Patients will receive Rapamycin (dose 0.6-2 mg/m\^2/day, adjusted to maintain a trough serum sirolimus level of 2-4 ng/mL.) every day starting from 7 days before first injection of AAV9 until four months after second injection.

Same volume as rAAV9-DES-hGAA injection will be used.

Patients will receive Rituxan (dose: 750 mg/m\^2 twice) 21 and 7 day prior first AAV9 injection, with a Rituxan dose 375 mg/m\^2 on the day of the injection. Rituxan will be repeated 7 days prior to the 2nd injection of the vector. The maintenance dose of Rituxan will be 375 mg/m\^2.

25-50mg will be provided before each Rituximab dose.

We will provide 650 mg of tylenol before each dose of Rituximab.

Lidocaine will be used based on standard of care: Percutaneous infiltration, concentration 0.5-1%, 1-10 mL, 5-300mg total dose.

Topical anesthesia cream will be used prior to gene therapy/saline injection.