Patent ID: 7879817

Claim:
A hyaluronic acid compound in which a non-steroidal anti-inflammatory drug is bound to hyaluronic acid through a covalent bond, wherein a partial structure of a hyaluronic acid disaccharide unit into which the anti-inflammatory drug is introduced is represented by the following formula (1): Y—CO—NH—R 1 —(O—R 2 ) n (1) wherein Y—CO— represents the glucuronic acid residue of the hyaluronic acid disaccharide unit; R 2 represents a hydrogen atom or a non-steroidal anti-inflammatory drug residue, and at least one R 2 is a nonsteroidal anti-inflammatory drug residue; —NH—R 1 —(O—) n represents a spacer residue in a spacer compound represented by H 2 N—R 1 —(OH) n having n numbers of a hydroxyl group; R 1 represents a linear or branched hydrocarbon group having from 2 to 12 carbon atoms which may have a substituent; —CO—NH— represents an amide bond of a carboxyl group in the glucuronic acid as a constituting saccharide of the hyaluronic acid with an amino group in the spacer compound; wherein a hydroxyl group in the spacer compound forms an ester bond with a carboxyl group in the non-steroidal anti-inflammatory drug residue; and n is an integer of from 1 to 3, wherein the hyaluronic acid compound has a degree of substitution of the non-steroidal anti-inflammatory drug of from 5 to 50 mol % per repeating disaccharide unit of hyaluronic acid, and the carbonyl group in a hyaluronic acid residue constituting the hyaluronic acid compound is present as an amide bond participating in the binding with the spacer-binding anti-inflammatory drug residue or as a free carboxyl group not participating therein, according to the degree of substitution of the non-steroidal anti-inflammatory drug residue.