Disclosed are methods of modulating a stress activated protein kinase (SAPK) system with an active compound, wherein the active compound exhibits low potency for inhibition of at least one p38 MAPK; and wherein the contacting is conducted at a SAPK-modulating concentration that is at a low percentage inhibitory concentration for inhibition of the at least one p38 MAPK by the compound. Also disclosed are derivatives of pirfenidone. These derivatives can modulate a stress activated protein kinase (SAPK) system.