The present invention aims to provide a means for effectively and conveniently treating diseases wherein corneal endothelial cells poor in proliferative capacity in vivo are damaged. The present invention provides a therapeutic agent for corneal endothelial dysfunction containing (R)-(+)-N-(1H-pyrrolo [2,3-b]pyridin-4-yl)-4-(1-aminoethyl)benzamide or a pharmacologically acceptable salt thereof (compound (Ia)) as active ingredient, an agent for promoting adhesion of corneal endothelial cells, containing compound (Ia), a culture medium for corneal endothelial cells, containing the agent for promoting adhesion, an implant for corneal endothelial keratoplasty, containing corneal endothelial cells, scaffold and compound (Ia), and a production method of a corneal endothelial preparation, including a step of cultivating corneal endothelial cells using the culture medium.
