Cell and gene therapy products are regulated by the FDA Center for Biologics Evaluation and Research, the division that issued the guidance on January 19. The guidance supplements the recommendations to all drug and biological product manufacturers, which the agency issued in June 2020 titled, "Good Manufacturing Practice Considerations for Responding to COVID-19 Infection in Employees in Drug and Biological Products Manufacturing; Guidance for Industry."

The new guidance specifically considers source donor materials (cells and tissues) and how cell and gene therapy products are manufactured -- cell expansion in culture, viral reduction steps, and formulations. The guidance noted that there are specific concerns regarding the manufacturing of cell and gene therapy products that may lead to unintended expansion of SARS-CoV-2 in autologous or allogeneic infected cells or tissues during the manufacturing process, which could result in an amplified SARS-CoV-2 viral load.

The agency recommends that manufacturers should review the current good manufacturing practice (cGMP) requirements and recommendations related to facility and equipment cleaning and sanitation and other manufacturing controls. Special considerations should include the assessment of donors, cellular and tissue source materials, manufacturing processes, manufacturing facility control, product testing, and the number of subjects that can be treated with the product.

The FDA recommends that cell and gene therapy product manufacturers perform a risk assessment that identifies, evaluates, and mitigates factors that may allow for transmission of SARS-CoV-2 by cell and gene therapy products. The agency recommends including a risk assessment in any investigational new drug application, biologics license application, or master file.