The FDA defines extractables as ‘compounds that can be extracted from a container closure system when in the presence of a solvent’, and leachables as ‘compounds that leach into the drug product formulation from the container closure as a result of direct contact with the formulation’.
These definitions refer to finished container closure systems; however, they may also be extended to consider extractables as chemicals generated under exaggerated temperature and time conditions in the presence of an appropriate solvent, and leachables as chemicals that migrate spontaneously from a container closure system, packaging components and/or processing equipment under recommended or routine conditions of use and storage.
The importance of these substances is that they may pose a safety risk to the patient either directly, or indirectly by altering the product’s physico-chemical properties through interactions with the API or excipients at any point during manufacture or processing, thereby adversely affecting product quality.
Knowing the compatibility of pharmaceutical products and contact materials helps pharmaceutical, toxicology, analytical and regulatory affairs professionals to assess the safety of leachable and extractable chemicals associated with drug product packaging, manufacturing systems and devices.