GSD-Ia is an inherited disorder of metabolism associated with life-threatening hypoglycemia, hepatic malignancy, and renal failure caused by the deficiency of glucose-6-phosphatase-alpha (G6Pase-alpha or G6PC). Current therapy, which primarily consists of dietary modification, fails to prevent long-term complications in many patients, including growth failure, gout, pulmonary hypertension, renal dysfunction, osteoporosis, and hepatocellular adenomas (HCA). Gene therapy-based techniques, which directly address the underlying genetic deficiency driving the disorder, offer the prospect of long-term remission in patients with GSD-Ia.
Researchers at the NIH National Insitute for Childhood Health and Diseases have developed an adeno-associated viral (AAV) vector for the treatment of glycogen storage disease type Ia (GSD-Ia).This new AAV vector that expresses human G6Pase-alpha directed by the tissue-specific human G6PC promoter/enhancer incorporates two improvements: 1) it expresses a variant of G6Pase-alpha with enhanced enzymatic activity; 2) it is codon optimized to achieve higher enzyme expression levels and enhanced enzymatic activity.
In vivo data is available.