Sio Gene Therapies Inc. (NASDAQ:SIOX) has reported positive six-month follow-up data from its low-dose cohort of the dose-escalation study of AXO-AAV-GM1. AXO-AAV-GM1 is an adeno-associated viral vector (AAV)9-based gene therapy candidate the company is developing for GM1-gangliosidosis treatment.
Sio Gene reports favorable and tolerability profile of AXO-AAV-GM1
According to preliminary data from the ongoing Phase 1/2 trial in five subjects in the low dose cohort, AXO-AAV-GM1 demonstrated a favorable safety and tolerability profile and also offered initial clinical disease stability indications. Gavin Corcoran, the company’s chief R&D officer, stated that they are delighted to report positive tolerability, safety, primary efficacy, and biomarker data for AXO-AAV-GM1. This is the first gene therapy to be evaluated in clinical studies for GM1 gangliosidosis treatment. GM1 gangliosidosis is a life-threatening disease that is caused by GLB1 gene mutations that affect beta-galactosidase enzyme activity. Gavin said that safety was a key measure in the study and the company is excited to witness a favorable safety profile in the first five subjects that received low-dose AXO-AAV-GM1.
Further, Gavin said that post-treatment they observed enhanced beta-galactosidase enzymatic activity which on average reached 38% if normal reference levels. Interestingly this is encouraging considering evidence from available medical literature suggests that for lysosomal storages diseases enzymatic activity increase is between 10-20% of normal levels and can result in stored lysosomal substrates clearance that could be related to disease progression. Gavin added that the consistent disease stabilization signs were encouraging across various neurodevelopmental measures in the five children in the study relative to the predictable decline witnessed in natural history trials.
Positive data supports advancing into a high-dose cohort of AXO-AAV-GM1
The data highlights the potential for experimental gene therapy in treating the underlying genetic disease cause, preserve functional results, and also minimize disease burden for families and patients. Most importantly the encouraging safety profile shown in the low-dose cohorts supports the company to advance to the high-dose cohort in the Phase 1/2 study. Gavin said that they are looking forward to offering more updates on the program in future medical conferences.