This disclosure describes novel 1-piperazinecarbonyl- carboxamides and 1-piperazinethiocarboxamides, such as 4'-chloro-4-(2-pyrazinyl)-1-piperazinecarboxanilide and 4'-cyano-4-(2-pyrazinyl)-1-piperazinethiocarboxanilide, pharmaeutical compositions containing same, a process for their preparation, and a method of treating atherosclerosis therewith.