The first oral presentation focuses on Precision's gene editing method for eliminating hepatitis B virus (HBV). Through the Arcus platform, Precision degraded HBV by 85% and reduced expression of hepatitis B surface antigens by 77% in human hepatocytes. This finding was supported by a 96% reduction in hepatitis B surface antigens by 96% in mice.
The next oral presentation will highlight a gene insertion approach to treat ornithine transcarbamylase (OTC) deficiency in non-human primates. Also utilizing the Arcus platform, this study resulted in stable and therapeutic levels of OTC lasting over one year. Additionally, the treatment showed high safety, with no evidence of liver histopathology or elevated liver enzymes in the treated primates.
Of the poster presentation, one will demonstrate hydroxyacid oxidase 1 (HAO1)-targeting and optimization of Arcus nucleases. Delivered by adeno-associated viruses, the HAO1-targeting nucleases showed a greater than 95% knockdown of the HAO1 protein in primate livers according to the study data. Multiple rounds of protein engineering of the nucleases also improved their potency and specificity.
Finally, the last poster presentation showcases a gene editing approach for shifting mitochondrial DNA heteroplasmy correlating with the m.3243A>G mutation, which is implicated in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. In this case, the Arcus platform was able to eliminate the mutation without impacting other functional mitochondrial DNA.