Host cell proteins (HCPs) are a common process-related impurity resulting from the production and expression of protein therapeutics in mammalian cells. As these impurities represent a potential risk to both the quality of the product as well as to the patient, they must be monitored at various stages of the production process and at product release to ensure thorough clearance. ELISA-based assays are commonly applied for this purpose. These assays involve the binding of HCPs to a commercially available or process-specific capture antibody and subsequent detection and quantitation using a fluorophore labeled detection antibody.

While ELISA assays generally offer the advantages of broad HCP recognition and sensitivity they also suffer from a limited linear dynamic range. Because the typical protein production process can show multiple logs of clearance between the protein harvest and final drug substance, this means that the dilution of each process sample pool must be optimized to the ELISA linear detection range. This is undesirable and can introduce repeat work for the testing lab if the approximate HCP level in the sample pool is not known. In this presentation, we will explore the application of using magnetic bead technology as an alternate approach to ELISA for HCP analysis.Results obtained from two populations linked to colorectal adenocarcinoma along with controls cohorts using automated data processing are discussed.