The field of cell and gene therapy development experiences explosive growth as the FDA and other regulatory agencies around the world continue their efforts to support innovators developing new cell and gene therapy products. Next generation recombinant vaccines and cell and gene therapy products require clinical and commercial manufacturing of various viral vectors produced using recombinant nucleic acid and cell culture technologies. To date, the FDA has approved a number of cell and gene therapy products, which insert new genetic material into a patient’s cells: Kymriah (Novartis), Luxterna (Spark Therapeutics), Yescarta (Kite Pharma/Gilead), Zolgensma (Avexis, a Novartis Company), Zynteglo (Bluebird Bio) . Regulatory agencies anticipate many more approvals in the coming years, as evidenced by the more than 900 investigational new drug (IND) applications for ongoing clinical studies in this area. In cell therapy and gene therapy, the most common expression platform is based on human embryonic kidney 293 (HEK 293) cells.
Viral vector manufacturing processes require rigorous analytics, including testing for process-related impurities such as HCP, host cell DNA, growth media additives and enzymes used in viral vector purification processes . 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.
 FDA News Release, Jan 28, 2020: “FDA Continues Strong Support of Innovation in Development of Gene Therapy Products”