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…