In one aspect, the invention relates to a crystalline form of the structure:, or a pharmaceutically acceptable salt thereof, having neprilysin inhibition activity. In another aspect, the invention relates to pharmaceutical compositions comprising this crystalline form; methods of using this crystalline form and its soluble form (I); and processes for preparing soluble (I) and crystalline (I') forms.在一個態樣中,本發明係關於具有如下結構的結晶形式:, 或其醫藥學上可接受之鹽,其具有腦啡肽酶抑制活性。在另一態樣中,本發明係關於包含此結晶形式之醫藥組合物;使用此結晶形式及其可溶形式(I)之方法;及製備可溶(I)及結晶(I')形式之方法。