After the approval by the National Medical Products Administration (NMPA), the first subject from the Shanghai-based Huashan Hospital of Fudan University on the morning of June 7 received an injection of JS016 – a recombinant, fully human, monoclonal neutralizing antibody against COVID-19, as reported by Xinhua. This is so far the world’s first clinical trial concerning using anti-COVID-19 antibody on a healthy human participant following confirming its protective efficacy in nonhuman primates.
The antibody, codeveloped by biopharmaceutical company Junshi Biosciences, the CAS Institute of Microbiology and others, is a reward of treasure-hunting from the blood of a convalescent donor once infected with COVID-19 (Nature 2020, doi: 10.1038/s41586-020-2381-y).
By taking a protein fragment close to the tip of SARS-Cov-2 surface spike protein as a bait, scientists fished out particular memory B-cells that carry the COVID-19 neutralizing antibody on the surface and contain the antibody genes in the core. As a result, they identified two specific human-origin monoclonal antibodies (CA1 and CB6) that show neutralizing ability in vitro against SARS-Cov-2. Notably, the CB6 antibody can inhibit SARS-CoV-2 infection in rhesus monkeys at both prophylactic and treatment settings. Structural analysis indicates the binding sites of SARS-CoV-2 in hACE2, its natural target, are highly overlapped with the binding sites of the virus in the CB6 antibody. Through joined efforts, this COVID-19 neutralizing antibody is currently in phase-I clinical trial, representing a big shot in fighting off the COVID-19 pandemic.
Couple of day earlier, using the same strategy, another group of scientists at the CAS Institute of Microbiology together with others, identified two human-origin monoclonal antibodies that could block the virus binding to its cellular receptor, and hence protect the antibody-given mice from COVID-19. Turn to page 78 for more detail.