POLYION COMPLEX CAPABLE OF EFFICIENTLY DELIVERING MRNA INTO LIVING BODY, AND DRUG AND METHOD FOR TREATING ARTHROPATHY IN WHICH SAID COMPLEX IS USED

摘要

The present invention provides a polyion complex which can efficiently deliver mRNA into a living body as well as a therapeutic agent and a therapeutic method of arthropathy in which the polyion complex is used. For example, there is provided a polyion complex comprising a cationic polymer and mRNA, wherein the cationic polymer is a polymer comprising a cationic unnatural amino acid as a monomer unit and the cationic unnatural amino acid is an amino acid having a group represented by —(NH—(CH₂)₂)_p—NH₂, wherein p is 2, 3 or 4, as a side chain.