First At-Home COVID-19 Serology Test From Symbiotica Granted EUA By FDA
April 6, 2021
The US Food and Drug Administration on Monday granted Emergency Use Authorization for Symbiotica's COVID-19 Self-Collected Antibody Test System, the first antibody test authorized for use with home collected dried blood spot samples.
"The authorization of the first prescription use, home collection antibody test will play an important role in helping health care professionals identify individuals who have developed an adaptive immune response from a recent or prior COVID-19 infection," Jeff Shuren, director of the FDA's Center for Devices and Radiological Health, said in a statement.
This test system has not been FDA cleared or approved but has been authorized for emergency use by FDA under an Emergency Use Authorization for use by Symbiotica Inc., located at 1350 Burton Drive, Vacaville, CA 95687;
This test system has been authorized only for detecting IgG antibodies to SARS-CoV-2, not for any other viruses or pathogens; and
The emergency use of this test system is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostics for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Federal Food, Drug and Cosmetic Act, 21 U.S.C. § 360bbb- 3(b)(1), unless the declaration is terminated or authorization is revoked sooner.
Symbiotica's COVID-19 Self-Collected Antibody System
For In vitro Diagnostic Use
For use under Emergency Use Authorization (EUA) only
For use with samples that are self-collected by an individual age 18 years or older, or that are collected by an adult from an individual 5 years of age and older.
The positive percent agreement (PPA) of the COVID-19 Self-Collected Antibody Test System was evaluated in unique DBS samples from symptomatic patients who were confirmed as SARS- CoV-2 positive via RT-PCR at least 8 days but no more than 45 days prior to sampling.
Antigen used: recombinant structural protein (S1 domain) of SARS-CoV-2
One sample gave a borderline result. For the more conservative measure of NPA, this result was considered positive in the analysis.
The negative percent agreement (NPA) of the COVID-19 Self-Collected Antibody Test System was evaluated in negative samples from subjects who were screened/assessed as negative based on no recent exposure to SARS-CoV-2 (within the prior 14 days) and not feeling ill or having a fever within the prior 3 days and/or were confirmed as SARS- CoV-2 negative via RT-PCR.
96.23% of users successfully collected their sample using the provided collection kit. Usability Evaluation Based on survey results, 90.6% of users responded with positive feedback for ease of use of the device.
FDA Spring/Summer profile and a Winter profile were tested. Results of the shipping stability study demonstrate 100% agreement between expected results after shipment under both winter and summer shipping conditions.
Collection device stability
Initial shelf-life for the collection device is set at 7 months at room temperature (15–30°C).
*On-going validation study to extend shelf life.
Analytical Robustness Testing
Studies on DBS specimens for downstream robustness testing was 100% agreement with the expected qualitative results, including drying time of blood sample, temperature and humidity, and other unique test characteristics.
Adaptive Immune Response to COVID-19
Clinical significance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously called 2019-nCoV) belongs to the family of coronaviruses and, like SARS-CoV, is classified in the genus Betacoronavirus. The new coronavirus originated in China in the city of Wuhan, Hubei province. It caused an infection wave, which has spread rapidly within the country and worldwide. Just a few days after the first report about patients with pneumonia of unclear origin, the causative pathogen was identified as SARS-CoV-2.
SARS-CoV-2 is predominantly transmitted by droplet infection via coughing or sneezing and through close contact with infected patients. Health care personnel and family members are among the high-risk populations. The zoonotic reservoir of the virus appears to be bats.
The incubation time of SARS-CoV is three to seven, maximally 14 days. The symptoms of SARS- CoV-2 infection are fever, coughing, breathing difficulties and fatigue. In most patients the infection manifests with symptoms of a mild febrile illness with irregular lung infiltrates. Some patients, especially elderly or chronically ill patients, develop severe acute respiratory distress syndrome (ARDS). The disease is fatal in around 3% of cases. In February 2020, the disease caused by SARS- CoV-2 was named COVID-19 by the WHO.
Suitable methods for diagnosis of SARS-CoV-2 infections are direct detection of the virus by polymerase chain reaction (PCR) primarily in sample material from the upper (smear) or lower respiratory tract (bronchoalveolar lavage fluid, tracheal secretion, sputum, nasopharyngeal secretion, oropharyngeal secretion, etc) and the detection of antibodies against SARS-CoV-2 in blood. The determination of antibodies enables confirmation of SARS-CoV-2 infection in patients with typical symptoms and in suspected cases without symptoms. It also contributes to monitoring and outbreak control.
The COVID-19 Self-Collected Antibody Test System is an enzyme-linked immunosorbent assay (ELISA) and a blood collection kit intended for qualitative detection of IgG antibodies to SARS- CoV-2 in human fingerstick blood dried blood spot (DBS) samples that are self-collected at home by an individual age 18 years or older or that are collected by an adult from an individual 5 years of age or older using the COVID-19 Self-Collected Antibody Test System Collection Kit when determined to be appropriate by a healthcare provider.
The COVID-19 Self-Collected Antibody Test System is intended for use as an aid in identifying individuals with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection.
The COVID-19 Self-Collected Antibody Test System should not be used to diagnose or exclude acute SARS-CoV-2 infection. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity.
This test system has not been FDA cleared or approved but has been authorized for emergency use by FDA under an Emergency Use Authorization for use by Symbiotica Inc., located at 1350 Burton Drive, Vacaville, CA 95687, which is certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. §263a, and meets requirements to perform high complexity tests.
This test system has been authorized only for detecting IgG antibodies to SARS-CoV-2, not for any other viruses or pathogens.
The emergency use of this test system is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostics for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Federal Food, Drug and Cosmetic Act, 21 U.S.C. § 360bbb-3(b)(1), unless the declaration is terminated or authorization is revoked sooner.
Specimens submitted using the COVID-19 Self-Collected Antibody Test System Collection Kit must be tested using the COVID-19 eSTAD.
Samples must be collected, transported, and stored using appropriate procedures and conditions. Improper collection, transport, or storage of specimens may hinder the ability of the assay to detect the target antibodies.
Results obtained with the COVID-19 Self-Collected Antibody Test System may not be used interchangeably with values obtained with different manufacturers’ test methods.
Results from antibody testing should not be used to diagnose or exclude acute SARS-CoV-2 infection or to inform infection status. An assay that directly detects the virus should be used to evaluate symptomatic patients for acute COVID-19.
False negative results may occur for immune-compromised individuals or individuals who receive immunosuppressive therapy.
Antibodies to SARS-CoV-2 are generally detectable in blood several days after initial infection, although the duration of time antibodies are present post-infection is not well characterized. Individuals may have detectable virus present for several weeks following seroconversion.
Negative results do not preclude acute SARS-CoV-2 infection and should not be used as the sole basis for patient management decisions. IgG antibodies may not be detected in the first few days of infection. The sensitivity of the COVID-19 eSTAD early after infection is unknown. Negative results do not preclude acute SARS-CoV-2 infection. If acute infection is suspected, direct testing for SARS-CoV-2 is necessary.
A positive result may not indicate previous SARS-CoV-2 infection. False positive results may occur due to cross-reactivity from pre-existing antibodies or other possible causes. Consider other information, including clinical history and local disease prevalence, in assessing the need for an alternative serology test to confirm an immune response. Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.
A negative result can occur if the quantity of antibodies for the SARS-CoV-2 virus present in the specimen is below the detection limit of the assay, or the antibodies that are detected are not present during the stage of disease in which a sample is collected.
A positive result may not indicate previous SARS-CoV-2 infection. Consider other information, including clinical history and local disease prevalence, in assessing the need for a second, different serology test to confirm an adaptive immune response.
For assays that employ antibodies, the possibility exists for interference by heterophile antibodies in the test sample. Patients who are regularly exposed to animals, or are subjected to medical treatments that utilize immunoglobulins or immunoglobulin fragments, may produce human anti-animal antibodies, e.g. HAMA, that interfere with immunoassays. These interfering antibodies may cause erroneous results.
The COVID-19 Self-Collected Antibody Test System’s COVID-19 eSTAD assay results should be interpreted in light of the total clinical presentation of the patient, including: symptoms, clinical history, data from additional tests, and other appropriate information.
The COVID-19 Self-Collected Antibody Test System’s COVID-29 eSTAD assay is intended for qualitative detection only. Test value itself cannot be used to determine the quantity of SARS-CoV-2 IgG antibodies.
This test is not to be used for screening donated blood.
The performance of this device has not been established in individuals that have received a COVID-19 vaccine. The clinical significance of a positive or negative antibody result following COVID-19 vaccination has not been established, and the results from this assay should not be interpreted as an indication or degree of protection from infection after vaccination.
The performance of this test was established based on the evaluation of a limited number of clinical specimens. The samples for the negative agreement study were all collected in the United States between May 2020 and June 2020. The samples from the positive percent agreement were collected in the United States between July 2020 and January 2021. The clinical performance has not been established in all circulating variants but is anticipated to be reflective of the prevalent variants in circulation at the time and location of the clinical evaluation. Performance at the time of testing may vary depending on the variants circulating, including newly emerging strains of SARS-CoV-2 and their prevalence, which change over time.