In contrast, there is a category of binding antibodies that are referred to as Nabs that can be of various antibody classes and have the unique ability to prevent cellular infection, potentially limiting initial infection and disease severity, as well as possibly preventing reinfection. qualitative and detect binding antibodies which include neutralizing antibodies. There is one EUA serology assay that specifically detects neutralizing antibodies. Multiple studies have demonstrated a positive correlation between binding and neutralizing antibody assays.? Antibody testing should not be used for diagnosing SARS-CoV-2 infection and utility is currently limited to seroprevalence studies, as an aid in supporting a multisystem inflammatory syndrome in children (MIS-C) diagnosis, or diagnosis in adults presenting late in the disease course, and identifying eligible donors for COVID-19 convalescent plasma (CCP).? As of May 2021, there are no recommendations from VU0364289 any of the professional societies (IDSA, CDC, AACC) for antibody testing to qualify for vaccine administration postnatural infection or for assessing adequate immune response due to vaccination. Introduction In 2019, a new coronavirus virus, SARS-CoV-2, emerged that would lead to a worldwide pandemic and highlight the importance VU0364289 of laboratory medicine in infectious disease management.1 In 2021, SARS-CoV-2 remains a priority for laboratory testing. Although diagnostic Rabbit Polyclonal to CK-1alpha (phospho-Tyr294) testing to determine who was infected with the virus was at the forefront of the pandemic, as serology testing became available, public interest in testing quickly rose and demanded that laboratories offer serology testing, even though antibody testing utility was limited. In the early days of the pandemic, March and April 2020, serology testing was not recommended for clinical purposes and was deemed of limited clinical value.2 , 3 Therefore, the FDA did not see a need for strict regulations for antibody testing. This led to a proliferation of SARS-CoV-2 antibody tests, dominated early on by lateral flow assays (LFA) imported from various parts of the world. At the time, the FDA only VU0364289 required that the manufacturer notify the FDA of their intent to bring an antibody assay to market without any data requirements to support the performance characteristics of the assay. The consequence was a rapid and unprecedented proliferation of unvalidated, expensive assays quickly made available to anyone who wanted access. In addition, many were confused about rapid tests and incorrectly assumed that because of the ease of use that these rapid tests could be used in any setting, such as physicians offices, without laboratory oversight or validation. The combination of public curiosity as to whether they had been infected with the virus and the lack of validated antibody tests used indiscriminately in any setting was accompanied by a considerable amount of bad press because many of the assays were inaccurate. This situation quickly escalated and highlighted the need for quality serology tests, FDA oversight, and the importance of the laboratory in validating serology assays. In early May 2020, the FDA issued new guidance for Emergency Use Authorization (EUA) claims for serology assays, that stated VU0364289 that, although manufacturers could notify the FDA of their intent to bring a serology assay to market as a first step to obtaining EUA, the manufacturer also had to provide supporting data to the FDA within 10?days of the notification. In addition, the FDA instituted an umbrella protocol that allowed for serology assays to be independently evaluated through NIH by agencies such as the National Cancer Institute (NCI), CDC, and Biomedical Advanced Research and.