New Horizons Diagnostics (NHD) teams up with The National University of Singapore (NUS) to develop a rapid Covid-19 antigen and immune status test using saliva as a sample

Rapid Antigen Tests (ART) have become a common way to test for COVID-19 infection, at home and for travel, due to their simple to use format. However, the majority of commercially available ARTs are reliant on sample collection using nasal swabs and recently have had issues over declining sensitivity. These tests do not provide immune status, as individuals are concerned over their level of immune protection and whether multiple booster vaccinations are
needed.

NHD has teamed with the NUS to develop two rapid assays which use saliva as a sample. One assay for COVID 19 antigen detection uses NUS antibodies and a mucin enzyme with the NHD rapid lateral flow immunoassay (LFI) format. The other test for immune status uses the NHD proprietary peptides in a LFI assay. The immune status assay measures the mucosal IgA and IgG antibodies in the saliva sample and has demonstrated correlation to the laboratory neutralization
assay.

Extensive LFI testing of saliva samples (n=616) differing by donor, date and sampling methods indicated a positive reaction from all neat saliva samples collected from fully vaccinated and unvaccinated but infected donors . The LFI strength of the test line significantly increased post second dose of a vaccine with a gradual decline after 6 months. This assay detected the presence of Anti-SARS-CoV2 IgA and IgG in infected individuals and tracked levels of IgG and IgA during the months post vaccination as well as infection in unvaccinated individuals. Additionally, the antigen detection assay demonstrated significant improvement in sensitivity compared to the currently available ART “Nasal Sample” test.

The assays will next be evaluated at the NUS and after successful completion of testing will be submitted for review under the FDA EUA program. For questions or comments, please contact: David Trudil [email protected]