Many injectable drug products, such as monoclonal antibodies and recombinant proteins, are susceptible to degradation over time when stored at ambient temperature. As such, they are stored, and subsequently delivered, in a lyophilized state - which enables a much longer shelf life. Lyophilization (also known as <em>freeze-drying</em>) is a process by which all water is removed from a drug product. Absent water, all metabolic processes stop, and drug products thus stored in a lyophilized condition are far more stable. At the time of use, the lyophilized drug product is reconstituted with water (or other appropriate solution) and delivered to the patient.