This technology has emerged as a great strategy for treating a range of diseases, including cancer, viral infections, and genetic disorders. In the US, five siRNA-based drugs have been approved, with several candidates undergoing clinical trials for conditions like COVID-19, HBV, cancer, and diabetes.

Despite promising capabilities, siRNA drugs require efficient and safe delivery systems, as bloodstream clearance and limited tissue penetration beyond the liver remain as major challenges. Vesicure Therapeutics, a biotech company from Suzhou China, recently introduced their exosome-based siRNA delivery platform in a proof-of-concept study, by efficiently shuttling cell survival siRNA cargo to inhibit tumor growth through intratumoral (it) injection (BioRxiv: doi: https://doi.org/10.1101/2023.08.26.554924).

Taking a significant stride forward, in a new study, Vesicure extended the feasibility of this exosome-siRNA technology in targeting KRAS mutation in a CDX (Cell line-derived xenograft) mouse model (BioRxiv: doi: https://doi.org/10.1101/2024.01.17.576015). The data revealed that intravenously (iv) injected exosomes were enriched in tumors. These 'KRAS siRNA carriers' exhibited excellent tumor retention and growth inhibition without significant toxicity to mice. This advancement marks progress in developing exosomes for extrahepatic siRNA drug delivery for targeting previously deemed undruggable targets to address unmet therapeutic needs.