Disclosed are chemical entities which are inhibitors of Nedd8-activating enzyme (NAE), namely, the compound {(1S,2S,4R)-4-[(6-{[(1R,2S)-5-chloro-2-methoxy-2,3-dihydro-1H-inden-1-yl]amino}pyrimidin-4-yl)oxy]-2-hydroxycyclopentyl}methyl sulfamate and pharmaceutically acceptable salts thereof; solid state forms thereof; and prodrugs thereof. Also disclosed are methods of using the chemical entities to treat disorders such as cancer.本發明揭示作為Nedd8-活化酵素(NAE)之抑制劑之化學實體,即化合物胺磺酸{(1S,2S,4R)-4-[(6-{[(1R,2S)-5-氯-2-甲氧基-2,3-二氫-1H-茚-1-基]胺基}嘧啶-4-基)氧基]-2-羥基環戊基}甲酯及其醫藥上可接受之鹽;其固態形式;及其前藥。本發明亦揭示使用該等化學實體治療諸如癌症等病症之方法。