Compounds, certain novel forms thereof, pharmaceutical compositions thereof and methods for their preparation and use

N- (2- (dimethylamino) ethyl) -1- (3 - ((4 -. ((2-methyl-1H-indol-5-yl) oxy) pyrimidin-2-yl) amino) phenyl methanesulfonamide ** ** formula and / or a pharmaceutically acceptable salt thereof.