(42c) The Role of Crystallizability, Polymorphism and Drug Species in Drug Candidate Selection

In the pharmaceutical industry, for a given intended indication, typically several analogues are transitioned from discovery medicinal chemistry into development. These molecules then undergo careful evaluation to generate data mainly around their potency, stability and toxicity. That information is crucial to make an informed decision about drug candidate selection. In recent years, developability of drugs is becoming increasingly important as growing data indicates that appropriate selection of polymorph and or species can have a profound impact on the development of a viable drug. For example, an ionizable drug with a desired potency and target binding specificity can have stability issues as parent molecule but can form a stable salt that can improve its developability. In this presentation, the increasing importance of drug developability, and in particular, crystallizability, polymorphism and drug species in candidate selection is described. In addition, the rationale behind drug selection with includes contributions of bioavailability, toxicity, stability and manufacturability is explained.