Host cell proteins (HCPs) are common impurities in biologic drug products and are an obligatory critical quality attribute (CQA). The individual protein contaminants that make up the HCP profile, however, may vary significantly among individual biologic products and expression systems. As such, the HCP profile must be analyzed to identify even low levels of potentially concerning species in a biologic drug to ensure safety and efficacy.

This whitepaper reviews fundamental aspects of HCPs pertaining to biologic drug development and current and emerging approaches to HCP analysis.