Atelocollagen‐Mediated Systemic DDS for Nucleic Acid Medicines

 The goal of our research is to provide a practical platform for drug delivery in oligonucleotide therapy. We report here the efficacy of an atelocollagen‐mediated oligonucleotide delivery system applied to systemic siRNA and antisense oligonucleotide treatments in animal disease models. Atelocollagen and oligonucleotides formed a complex of nanosized particles, which was highly stable against nucleases. The complex allowed oligonucleotides to be delivered efficiently into several organs and tissues via intravenous administration. In a tumor metastasis model, the complex successfully delivered siRNA to metastasized tumors in bone tissue and inhibited their growth. We also demonstrated that a single intravenous treatment of the antisense oligodeoxynucleotide complex suppressed ear dermatitis in a contact hypersensitivity model. These results indicate the strong potential of the atelocollagen‐mediated drug delivery system for practical therapeutic technology.