A once-daily controlled-release formulation of diacerein for treating inflammatory diseases, autoimmune diseases or their complications with reduced adverse side effects, comprising an active layer, a sustained-release film layer, and a delayed-release film layer, wherein said sustained-release film layer comprises an ethyl cellulose polymer, povidone, triethyl citrate and talc, and wherein said delayed-release film layer comprises a meth acrylic acid - methyl methacrylate copolymer or a methacrylic acid - ethyl acrylate copolymer, triethyl citrate and talcand methods of treating such diseases are disclosed.
