Lyophilization (freeze drying) is the process of dehydrating a drug product at low temperature and reduced pressure. Absent water, degradation processes are greatly reduced; thus, it helps to enhance drug product stability. Moisture-sensitive drug products are often marketed in lyophilized form. For a primary package system, the selection of appropriate components is essential to prevent risks associated with alteration of the lyophilized drug product prior to reconstitution and use.