Biologic drugs, which aim to treat complex diseases such as cancer, are a fast-growing market. Over the past decade, biologics have become even more structurally complex than their predecessors. As a result, the parenteral dosage forms of these highly complex molecules are more sensitive not only to temperature and other environmental conditions, but also to the extractables and leachables (E&L) that can be released from primary packaging materials. While extractables are substances that are extracted by subjecting the packaging material to aggressive conditions for extended times, leachables migrate into formulations after preparation and storage under standard conditions.