BACKGROUND

img02The ultimate efficacy of a drug molecule depends on its interactions with the appropriate target in the human body at the molecular level. However, the delivery of the drug in a safe and economical way partly depends on the properties of its solid-state, at least in those cases involving a solid dosage form. API manufacturing is a complex process and may consist of many steps such as, hydrogenation, crystallisation, filtration, drying, milling etc., all of which need to be tightly controlled in order to assure product quality. Crystallinity confers various advantages during isolation, processing and storage of the drug, such as better impurity rejection, improved handling characteristics, such as sticking and flow and, in the majority of cases, better physical and chemical stability. These factors are particularly important in defining a robust processing platform and storage conditions so that a stable product can be delivered to patients. The crystallisation process is a critical step in the API manufacturing process and for delivering “product” in its final form, with some 70 % of products going through a crystallization step at some point in their manufacture.