The present invention relates to a solid dispersion containing a compound represented by General Formula (I): wherein R1 is an unsubstituted phenyl group or a phenyl group substituted with a substituent; the substituent is an alkyl group having 1 to 8 carbon atoms, an alkyl group having 1 to 8 carbon atoms substituted with a halogen atom, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a formyl group, a carboxyl group, a halogen atom, a phenyl group or a phenoxy group; R2 is a cyano group or a nitro group; R3 is a hydroxyl group; X is an oxygen atom or —S(O)n—; n is an integer of 0 to 2; Y is an oxygen atom or a sulfur atom, or a pharmaceutically acceptable salt thereof and a hypromellose derivative.