Sarina Saeidi1, Kiing Seng Wong1, Neil Fullarton1, Mitchell Geer2, Christian Witte1, David Tatnell 1, Gerda Gasiunaite2, Stella Pelengaris2, Michael Khan2 & Elijah Nazarzadeh1
1 Acu-Flow Limited, 255 St Vincent Street, Glasgow, G2 5QY, UK
2 Argonaute RNA Limited, Saint Philips Central, Bristol BS2 0XJ, UK
Summary
Small interfering RNA (siRNA) therapeutics enable gene-specific inhibition by selectively degrading disease-related mRNAs, offering strong potential for treating genetic and inflammatory disorder. However, systemic delivery remains a key limitation due to siRNA’s inherent instability in vivo. Conjugating siRNA to ligands or polymers significantly enhances both its stability and functionality, making it a more viable therapeutic agent for gene therapy. Among these, inhalable siRNA formulations can deliver drugs directly to the lungs, showing great potential for treating respiratory diseases. In this study, we evaluated the nebulisation of GalNAc-conjugated siRNA using the Nebu~Flow acoustic-based nebuliser. Our results demonstrate that GalNAc-conjugated siRNA can be nebulised without degradation. The aerosolised siRNA maintained structural integrity and retained its gene-silencing activity in primary mouse hepatocytes, demonstrating comparable knockdown efficiency to un-nebulised samples across both free uptake and transfection conditions. These findings demonstrate the capability of efficiently nebulised GalNAc-conjugated siRNAs without losing the biological activity. This has the potential for stable, effective, and non-invasive respiratory delivery for pulmonary and systemic gene therapy applications, which requires further validation in next studies.