The present invention provides a lipid-rich plaque regressing agent comprising a compound represented by Formula: ##STR1##

in which ring A is a cyclic hydrocarbon or the like; ring B is a heterocyclic ring or the like; each of X and Y is —NR¹— (in which R¹ is a hydrocarbon or the like); D is a C_1-3 alkylene group or the like; E is —NH— or the like; G is a bond or the like; and Ar is an aryl or the like; D may be taken together with a constituent atom of the ring B to form a ring, and R⁴ may be taken together with a constituent atom of the ring B to form a ring.