Host Cell Protein Impurities in Viral Vector Manufacturing: A Critical Quality Attribute for Product Efficacy and Safety

Viral vectors are a common delivery system used in gene therapy to introduce healthy copies of genes into cells. Viral vector manufacturing processes require rigorous analytics, including testing for process-related impurities such as host cell proteins (HCP), host cell DNA, growth media additives and enzymes used in viral vector purification processes [Cellular and Gene Therapy Guidances]. Even after multiple purification steps, significant levels of HCP impurities can be present. While low levels of most impurities can be inconsequential, patient safety demands that HCPs be eliminated or reduced to the lowest levels practical to prevent problems such as adverse immune reactions or other off-target biological effects. Impurities can have significant cost implications in drug development and manufacturing processes and negatively impact stability. By identifying HCPs early on, companies can reduce process development costs, better assure product efficacy and safety, and help promising technologies get to market faster.

A robust and broadly reactive HCP immunoassay is a critical tool for monitoring purification process consistency as well as final viral vector purity and is the gold standard method for process monitoring and product release testing for HCPs. It is critical to ensure that the selected HCP immunoassay method is fit for its intended use. Regulatory agencies around the world have put measures in place to ensure the HCP immunoassay used by a sponsor is fit for the purpose of monitoring purification process consistency and product lot release. A well-developed and qualified HCP immunoassay will ensure that HCPs have been reduced to safe levels and that the purification process is consistent from batch to batch. It is advised to employ orthogonal methods to demonstrate antibody coverage to individual process-specific HCPs to support use of a particular HCP immunoassay. Equally important is to qualify the assay for dilution linearity, accuracy, and precision.

Cygnus Technologies, part of Maravai Life Sciences, offers generic HCP ELISA Kits for 24 different expression platforms, advanced orthogonal antibody coverage analysis services, HCP identification in process samples and drug substances by AAE-MS™, generic assay qualification services, and expert process-specific antibody and assay development services. Cygnus’ reputation for quality is recognized by the industry and global regulatory agencies, with several HCP ELISA Kits supporting 21 of 21 marketed gene and CAR-T cell therapies. Cygnus’ proprietary technology has also been utilized to develop over 150 process-specific antibodies and immunoassays for many global biopharmaceutical companies.

For more information, visit: https://www.cygnustechnologies.com/gene-therapy-and-vaccine-development