A Phase 1/2 Study of Intravenous Gene Transfer With an AAV9 Vector Expressing Human Beta-galactosidase in Type I and Type II GM1 Gangliosidosis

Summary

Background: GM1 gangliosidosis is a disorder that destroys nerve cells. It is fatal. There is no treatment. People with GM1 are deficient in a certain enzyme. A gene therapy may help the body make this enzyme. This could improve GM1 symptoms. Objective: To test if a gene therapy helps Type I and Type II GM1 gangliosidosis symptoms. Eligibility: Type I subjects will be male and female \>= 6 months \<= 12 months of age at the time of full ICF signing. Type II subjects will be male and female \> 12 months old and \< 12 years old at the time of full ICF signing. Design: Participants will be screened with their medical history and a phone survey. Participants will stay at NIH for 8-10 weeks. Participants will have baseline tests: Blood, urine, and heart tests Hearing tests Ultrasound of abdomen EEG: Sticky patches on the participant s head will measure brain function. Lumbar puncture: A needle will be stuck into the participant s spine to remove fluid. MRI scans, bone x-rays, and bone scans: Participants will lie in a machine that takes pictures of the body IQ tests Neurology exams Central line placement Skin biopsy: A small piece of the participant s skin will be removed. Speech tests Participants will have an x-ray while swallowing food. Participants will take drugs by mouth and IV. This will get their immune system ready for therapy. Participants will get the gene therapy by IV. They may stay at NIH for a week to watch for side effects. Participants will have visits 3 and 6 months after treatment. Then visits will be every 6 months for 2 years. Then they will have a visit at 3 years. Visits will take 4-5 days. Participants will return to NIH once a year for 2 years for tests in an extension study....

Description

Eligibility

Age range

0–12 years

Sex

All

Healthy volunteers

No

Interventions

• Biological
  AAV9-GLB1

  The risks of administering this treatment in a subject with GM1 gangliosidosis are not completely known. The major risk associated with intravenous infusion is from the subject s immunological response to the viral capsid and/or the beta-gal protein. To reduce this possibility, immune modulation therapy is being started prior to vector delivery and maintained for six months afterward. There is a theoretical risk that the integration of a small percentage of the rAAV vector DNA into the host cell genome could cause cellular transformation to cancer cells and lead to a malignancy. This has never been seen in subjects receiving intravenous AAV9 gene therapy so the risk of this complication, is likely very low.

• Procedure
  Abdominal ultrasound

  Abdominal ultrasound will be performed as part of screening and safety follow- up studies. The ultrasound will be performed in a radiology department and will take approximately 20-30 minutes.

• Drug
  Rituximab

  We are proposing the use of immune modulation to transiently deplete B-cells using rituximab. It will be infused at -21 days and -14 days before gene transfer.

• Drug
  Sirolimus

  Sirolimus is a macrocytic lactone that inhibits T lymphocyte activation and proliferation by inhibiting activation of mammalian Target of Rapamycin (mTOR) kinase that suppresses cytokinedriven T-cell proliferation. We plan to give sirolimus from day -21 to Day 90 with option to extend to day 365 if clinically indicated.

Location