Abnova & Leadgene Develop High Sensitivity COVID-19 Viral Antigen Rapid Tests

Neihu, Taiwan (October 26, 2020)

Abnova announced today that both Abnova and Leadgene are working together to develop high sensitivity COVID-19 viral antigen rapid tests. Rapid viral antigen testing is critical to the tracking and containment of viral transmission while RT-PCR testing is essential for viral diagnosis. The main impediment for widespread adoption of COVID-19 viral antigen testing is the inadequate detection sensitivity. Under FDA regulatory stringency, the viral antigen rapid test is required to have escalating sensitivities from clinical laboratory to point-of-care (POC) to home settings. To meet these unmet needs, Abnova and Leadgene have developed technologies to increase both colorimetric and fluorescent detection sensitivity.

To increase colorimetric sensitivity, Abnova and Leadgene combined multiple antibody pairs in the lateral flow chromatographic immunoassay. Currently, the five FDA approved COVID-19 viral antigen tests (BD, Quidel, LumiraDx, Abbott, and Access Bio) used an antibody pair targeting only the nucleocapsid protein. Abnova and Leadgene used antibody pairs targeting both nucleocapsid and spike proteins which require more sophisticated gold nanoparticle conjugation. To increase the fluorescent sensitivity, Abnova utilized a specialized fluorescent bead to conjugate the detecting antibodies while Leadgene developed a proprietary manufacturing process to integrate the conjugate complex onto the nitrocellulose membrane of the lateral flow.

COVID-19 viral antigen testing provides the actual status of protein (not molecular) viral load carries by a healthy, infected, or asymptomatic individual. The presence of such protein viral load signifies elevated person-to-person transmission risk in a multitude of environmental settings, such as schools, airports, businesses, and nursing homes. When it comes to preventing the spread of the virus and containing outbreaks, it’s the infectious people you want to identify and isolate. Viral antigen testing is ideally suited to yield positive results precisely when the infected individual is maximally infectious.