Crystalline Forms of Compound I: and pharmaceutically acceptable salts thereofare disclosed. Pharmaceutical compositions comprising the same, methods of treating cystic fibrosis using the same, and methods for making the same are also disclosed.本發明揭示化合物I之結晶形式: 及其醫藥學上可接受之鹽。亦揭示包含其之醫藥組合物、使用其治療囊性纖維化之方法及製造其之方法。