The present invention provides a type I insulin-like growth factor receptor (IGF-1R) inhibitor comprising, as an active ingredient, an indazole derivative represented by Formula (I):{wherein R1 represents -NR4R5 [wherein R4 represents a hydrogen atom or the like, R5 represents substituted or unsubstituted lower alkyl, -C(=O)R6 (wherein R6 represents substituted or unsubstituted lower alkyl, substituted or unsubstituted aryl or the like), or the like], or the like, and R2 and R3 may be the same or different and each represents a hydrogen atom, hydroxy, substituted or unsubstituted lower alkoxy, or the like} or a pharmaceutically acceptable salt thereof, and the like.
