Solid Form Patents: Part I – Introduction and Laying the Genus/Species Foundation
Pharmaceutical products are typically dosed as solids, liquids (e.g., solutions) or gases. In gases and liquids, the molecules are tumbling; in solids, however, the molecules are essentially frozen in place, forming three-dimensional networks. When those networks are ordered, they are called crystalline…. Where the same chemical compound can exist in multiple crystalline forms is called polymorphism, with each crystalline form called a polymorph. When the compound is an element, as with carbon, it is referred to as allotropism. Predicting whether a chemical compound will be polymorphic, what that polymorph might be, and the properties thereof are notoriously challenging feats. Because polymorphs or other crystalline forms can have significantly different drug solubility and dissolution properties, it is not surprising that they are often the subject of patent applications in the pharmaceutical arts.