STEP (Stimuli-responsive Traceless Engineering Platform) for Delivery of Genetic Medicines

Couragene believes that delivery of gene and biologic therapies should be safer and more efficient.

Couragene's proprietary STEP (Stimuli-responsive Traceless Engineering Platform) technology is developed to leverage chemical engineering approaches to enable efficient intracellular delivery of genetic medicine payloads, such as proteins, gene editors, antibodies, mRNA, antisense oligos (ASOs), and DNA, etc. The chemically engineered payloads can penetrate cells. Within the cells, the payloads are released and fully recover their biological functions.

Delivery of genetic medicines to the brain has been particularly challenging due to physiological barriers. Existing delivery vehicles, including viral vectors and lipid nanoparticles (LNPs), suffer from specific safety concerns and technical limitations. Viral vectors such as Adeno-associated viruses (AAVs) are associated with potential genotoxicity and immunogenic risks and are limited by the size of payloads they can package. Brain-wide delivery of typical LNPs is difficult because LNPs are too big for brain extracellular space (ECS). Payloads engineered by Couragene’s STEP technology are small in size. For example, the CRISPR-Cas9 gene editor engineered by Couragene’s STEP technology (STEP-CRISPR) has an average diameter of 12.4 nm, optimal for brain penetration.

Couragene’s STEP technology has been demonstrated to enable efficient delivery of CRISPR-Cas9 gene editors to embryonic fibroblast cells from a dTomato reporter mouse line. More importantly, Couragene’s STEP-CRISPR is capable of efficient brain-wide editing to activate the expression of a yellow fluorescent chimeric protein (YFCP) in a transgenic mouse line.