GMP compels all Advance Therapy Medicinal Products (ATMPs) to meet quality controls to ensure the final product is adequate and safe for the patients. These quality controls depend on the nature of each product: gene therapy, cell therapy, or tissue engineering. They comprise potency and identity tests along with safety controls, such as sterility and absence of mycoplasma and endotoxins. In terms of quality control for gene therapy, viral vector identity, immunophenotyping/titration, and the absence of adventitious viruses are also necessary. However, the current official guides expose recommendations more than mandatory assays, which leads to ambiguity, as the mentioned analyses are insufficient to ensure the therapy's quality and safety.

Different kinds of lentivirus are produced at Creatio using different protocols, which leads to variability in the final product. To mitigate this, Creatio has established new quality controls for viral vector gene medicinal products that allow determining DNA and protein impurities, p24 quantification, and the integrity of the chimeric gene of interest. All these assays have been set up and performed using various techniques like PCR and ELISA combined with cell culture techniques. These analyses combined with the already established quality controls concede a profound characterization of the product that guarantees the quality of the medicinal product and allows a detailed control of the manufacturing process. We propose to establish these quality controls to produce viral vector gene medicinal products to harmonize the production at different manufacturing facilities.