Macrocyclic polymorphs, compositions comprising such polymorphs, and methods of use and manufacture thereof

摘要

Disclosed is a crystalline polymorph of Formula I comprising tiacumicin (also known as lipiarmycin and fidaxomicin), wherein the polymorph is characterised by a powder x-ray diffraction pattern with at least peaks at diffraction angles 2-theta of 7.7, 15.0 and 18.8 plus or minus 0.2. The polymorph of Formula I is useful for treating bacterial infections such as a gastrointestinal infection of Clostridium difficile.