Patent ID: 8524273

Claim:
A transdermal patch for sustained release at a constant concentration comprising a backing and a pressure-sensitive adhesive layer which comprises multiple layers, wherein the pressure-sensitive adhesive layer comprises (i) a drug reservoir layer containing a drug and an acrylic pressure-sensitive adhesive; and (ii) a skin adhesion layer containing a styrene-isoprene-styrene block copolymer on the skin contact side, the acrylic pressure-sensitive adhesive is a copolymer comprising (meth)acrylic acid having a carboxyl group as a monomer unit, and the drug is represented by the general formula (I) [Chem. 1] wherein R is selected from the group consisting of 2-isopropoxyethoxymethyl, carbamoylmethyl, and 2-methoxyethyl groups, or a pharmaceutically acceptable salt thereof, wherein the drug reservoir layer further comprises a solubilizer and/or a permeation enhancer, wherein the skin adhesion layer is laminated on the drug reservoir layer, wherein the transdermal patch provides sustained release of the drug at a constant release rate over 24 hours upon application.