Abstract Body (Do not enter title and authors here): Introduction: While gene therapy holds promise as a revolutionary approach for treating cardiovascular diseases, several hurdles remain that need to be overcome. Transcutaneous ultrasound mediated gene delivery (UMGD) has emerged as a pivotal tool in delivering noninvasive in vivo gene therapy to the heart with precision and efficacy. SonoThera is developing a novel ultrasound-guided nonviral gene therapy platform based on UMGD that allows selective targeting of specific organs and tissues within the body in a safe, redosable, durable, and titratable manner.
Methods: To evaluate the potential of UMGD for safe and efficient transgene delivery to the heart, we developed a technology platform utilizing novel acoustic profiles, next-generation genetic payloads, and FDA-approved ultrasound components. The delivery process involves intravenous co-administration of nucleic acid payloads (e.g. DNA or RNA) and ultrasound contrast agents (a.k.a microbubbles), coupled with targeted application of externally applied ultrasound energy to guide the DNA into specific tissues via sonoporation. In vivo bioluminescence imaging of firefly luciferase reporter gene expression in the heart in wild type mice was evaluated using an IVIS imaging system at multiple timepoints. Mouse and macaque heart tissues were analyzed for reporter gene presence and expression. Multiple clinical and molecular safety assessments were evaluated in mice and macaque using established methods.
RESULTS: Efficacious delivery of cutting-edge non-viral genetic DNA payloads through UMGD led to rapid, robust, durable, dose-responsive transgene expression in the hearts of wildtype mice and demonstrated excellent tolerability for repeated administration. Gene expression durability was followed for 2 months after single treatment in mice. Following repeated treatments, a significant increase of gene expression was observed compared to a single treatment. Reporter gene presence and expression were detected in the analyzed mouse and macaque heart tissues. Ex-vivo bioluminescence imaging of excised heart tissue after subsequent UMGD showed precision delivery to the heart without affecting off-target tissues.
CONCLUSION: This study establishes a novel UMGD platform as a promising strategy for delivering transgenes in vivo using advanced non-viral genetic payloads, thus setting the stage for future development of genetic therapies for cardiac diseases.