| abstract |
A biodegradable copolymer having the constituent units derived from 4-hydroxyproline and an aliphatic α-hydroxycarboxylic acid, represented by the structures (I) and (II):n n n wherein X represents a hydrogen atom, an acyl group having the formula RCO- where R is a hydrocarbon or an alkoxy group having 1 to 20 carbon atoms, and Y represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and m and n are independently integers of 1 or more, m + n is at least 10, and m/(m + n) is at least 0.01 and a pharmaceutical composition containing the same. |