SUSTAINED-RELEASE MICROSPHERE CONTAINING SHORT CHAIN DEOXYRIBONUCLEIC ACID OR SHORT CHAIN RIBONUCLEIC ACID AND METHOD OF PRODUCING THE SAME

摘要

A sustained-release microsphere formulation containing a short chain deoxyribonucleic acid or a short chain ribonucleic acid as an active ingredient, which has improved sustained-release properties and long-lasting efficacy, is provided. A fine particle formulation, encapsulating stably a short chain deoxyribonucleic acid or a short chain ribonucleic acid, being capable of inhibiting, for a long period, expression of a specific protein related to a disease, and which can be administered by injection or transmucosally, and a production method of the same are provided. A sustained-release microsphere formulation containing a short chain deoxyribonucleic acid or a short chain ribonucleic acid, particularly siRNA, as an active ingredient, especially a sustained-release microsphere prepared through a w₁/o/w₂ type emulsion, is characterized in that a positively charged basic substance, such as arginine, polyethylenimine, a cell permeable peptide, poly-L-lysine or poly-L-ornithine, is included in an in vivo degradable polymer.