The invention provides salts of methyl (3-{[[3-(6-amino-2-butoxy-8-oxo-7,8-dihydro-9H-purin-9-yl)propyl](3-morpholin-4-ylpropyl)amino]methyl}phenyl)acetate, pharmaceutical compositions containing them and their use in therapy.本發明提供一種(3-{[[3-(6-胺基-2-丁氧基-8-側氧-7,8-二氫-9H-嘌呤-9-基)丙基](3-嗎福啉-4-基丙基)胺基]甲基}苯基)醋酸甲酯的鹽類、包含其之醫藥組成物及其在治療上的用途。