Optical isomer or racemic mixture of phenethylsulfones substituted alpha to the phenyl group with a 1-oxoisoindoline or 1,3-dioxoisoindoline for use in the treatment of an inflammatory, infectious, immunological or malignant disease. A typical embodiment is 2-[1-(3-ethoxy-4-methoxyphenyl)-2-methylsulfonylethyl]-4-aminoisoindoline-1,3-dione.