Abstract: A homopolymer of acrylic acid or methacrylic acid derivatives having the general formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or methyl group; R.sup.2 is a residue of a compound having physiological activity; X is a residue of a compound having a hydroxyl group, amino group or carboxyl group at both ends in its chemical structure after bonding between such compound and acrylic or methacrylic acid, and between such compound and the physiologically active compound; and the homopolymer has a number-average molecular weight ranging from 20,000 to 200,000; and a process for the preparation thereof by a mechanochemical polymerization reaction; as well as a polymeric drug and prodrug comprising the homopolymer.

Abstract: A homopolymer of acrylic acid or methacrylic acid derivatives having the general formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or methyl group; R.sup.2 is a residue of a compound having physiological activity; X is a residue of a compound having a hydroxyl group, amino group or carboxyl group at both ends in its chemical structure after bonding between such compound and acrylic or methacrylic acid, and between such compound and the physiologically active compound; and the homopolymer has a number-average molecular weight ranging from 20,000 to 200,000; and a process for the preparation thereof by a mechanochemical polymerization reaction; as well as a polymeric drug and prodrug comprising the homopolymer.

Abstract: By forming a multi-layer preparation comprising a tablet or granule containing a medicine as the core and the outermost layer comprising a plasma-decomposable polymer and a plasma-crosslinkable polymer and irradiating the outermost layer with a plasma about release-regulating preparations according to the plasma irradiation, the direct exposure of the medicine to the plasma can be avoided and the release pattern can be controlled more easily.