Residual host cell proteins (HCPs) carried over from expression systems are a potential safety and regulatory risk for biopharmaceuticals. Their risks, for example immunogenic reactions, do not necessarily correlate with their quantities as even small traces of certain HCPs can be highly immunogenic.
Many HCPs have physio-chemical properties that cause them to co-purify with the drug protein. The complexity of the HCP challenge requires a holistic approach to achieve a maximum of specificity/coverage for the analytical tools used during process development and in QC testing.
Since HCPs are a fact of life in all biopharmaceuticals, their quantification and characterization at all stages of downstream purification is a top priority. In this article, Olaf Stamm talks about the future of residual HCPs and more.