New guidance from the U.S. Food and Drug Administration (FDA) released this week reaches out to medical product developers to address effective means of modifying various medical products to meet the threats posed by new variants of SARS-CoV-2.
SARS-CoV-2, the virus that causes COVID-19, has already seen several widespread variants that threaten to increase its infectiousness or vaccine resistance. Such evolutions are typical among infectious diseases, having been previously demonstrated by viruses like influenza and HIV.
“We know the country is eager to return to a new normal, and the emergence of the virus variants raises new concerns about the performance of these products,” Acting FDA Commissioner Janet Woodcock said. “By issuing these guidances, we want the American public to know that we are using every tool in our toolbox to fight this pandemic, including pivoting as the virus adapts. We need to arm health care providers with the best available diagnostics, therapeutics, and vaccines to fight this virus.”
For vaccines, the FDA noted that authorized vaccines seem to remain effective in protecting against currently circulating strains of SARS-CoV-2. However, it would not rule out the possibility of a variant becoming moderately or fully resistant to the antibody response they elicit, meaning manufacturers should be prepared to modify vaccines to address such variants.
The FDA expects that while manufacturing information will generally remain the same, modified vaccines should be studied in non-vaccinated individuals and those previously vaccinated. In terms of clinical data, the agency recommended effectiveness analyses be supported by data from clinical immunogenicity studies. Its new guidance outlined recommendations for safety assessments that support EUAs for modified vaccines. The FDA has not yet determined if modified COVID-19 vaccines may be authorized in the future without the need for new clinical studies.
Regarding tests, the FDA offered information on evaluating the potential impact of emerging and future viral genetic mutations on existing diagnostics. Such mutations can alter the success of tests, although, at this time, the impacts have not been deemed significant. According to the new guidance, the FDA is actively seeking to understand the public health impact of new variants and their impact on test performance. It also provided recommendations for test developers, such as considering the potential for future viral genetic mutations and routine monitoring to track the potential impact of new mutations.
As to therapeutics, the FDA urged developers of monoclonal antibodies to be aware that some authorized versions have proven less effective against some SARS-CoV-2 variants. It recommended various approaches to create non-clinical, clinical, and chemistry, manufacturing, and controls data that could support an EUA for monoclonal antibody products more effective against emerging variants. It also revised guidance to cover the changing nature of COVID-19 drug development, including the variants and the availability of authorized vaccines. Developers are encouraged to monitor genomic databases continuously for SARS-CoV-2 variants.
In the meantime, the FDA continues to stress that Americans should get tested, vaccinated, and continue to wash hands, wear masks and maintain social distance.