Novel solid forms of Raltegravir potassium comprising the active ingredient N-[2-[(4Z)-4-[[(4-fluorophenyl)methylamino]-hydroxymethylidene]-1-methyl-5,6-dioxopyrimidin-2-yl]propan-2-yl]-5-methyl-1,3,4-oxadiazole-2-carboxamide as potassium salt co-crystal with cyclamic acid, saccharin, stearic acid or succinic acid. The multi-component crystalline forms show improved properties such as dissolution kinetic and hydration stability.
