This invention relates to a new crystalline form of the succinate salt of the epithelial sodium channel (ENaC) blocker 3-(3-{2-[(E)-3,5-Diamino-6-chloro-pyrazine-2-carbonylimino]-1,3,8-triaza-spiro[4.5]decane-8-carbonyl}-benzenesulfonylamino)-propionic acid dipropylcarbamoylmethyl ester, pharmaceutical compositions comprising said crystalline form, uses of said crystalline form and pharmaceutical compositions, and methods for preparing said crystalline form.本發明係關於上皮鈉通道(ENaC)阻斷劑3-(3-{2-[(E)-3,5-二胺基-6-氯-吡嗪-2-羰基亞胺基]-1,3,8-三氮雜-螺[4.5]癸烷-8-羰基}-苯磺醯基胺基)-丙酸二丙基胺甲醯基甲基酯之琥珀酸鹽之新穎結晶型式、包含該結晶型式之醫藥組合物、該結晶型式及該等醫藥組合物之用途以及製備該結晶型式之方法。