By Dr. Susan M. Reutzel-Edens, Ph.D. FRSC
President, SuRE Pharma Consulting, LLC

Drug product design generally begins with identifying, oftentimes through experimental crystallization screening, solid forms in which to isolate and store the drug substance. When performed under different conditions, crystallization can yield different forms (polymorphs, solvates) with different particle sizes and shapes, thus providing an opportunity to engineer drug crystals to desired specifications. Solid forms must be selected from potentially numerous options to meet the design requirements for a drug product. The path to even one commercially-viable form can, in some cases, be lengthy and difficult, however. Under immense pressure to shorten development timelines and reduce costs, the pharmaceutical industry is keen on right-sizing the time and effort spent on finding suitable solid forms. In this presentation, applications of crystal structure prediction to enhance the effectiveness of experimental solid form screens and achieve molecular-level understanding of structures and their properties are explored. Recent advances in predicting crystal form stability under real-world conditions, which have redefined the state-of-the-art in crystal modeling, are also discussed.