In drug development, designing a formulation for a drug product (a tablet, for example) calls for careful attention to both the physical and chemical properties of the active pharmaceutical ingredient (API or drug substance). It also requires awareness that certain physical attributes, such as particle size distribution of the drug substance, can change with processing conditions and changes in the synthesis route that is employed. If the drug substance has unfavorable interactions with any of the excipients, it can have a negative effect on the shelf life and performance of the drug product and can potentially cause harm to the patient.

So what can a pharmaceutical company do to recognize both unfavorable drug substance properties and incompatibility between an API and its formulation? Finding the answer to this question early allows a drug manufacturer to avoid potential risks to the patient as well as costly interruptions during development.