Beroni Group has announced successful completion of SARS-CoV-2 pseudovirus neutralization assay in collaboration with GenScript Biotech Corporation. The assay targets on coronavirus-specific nanobodies and tests affinity and efficacy to prevent the virus infection.

On September 7, 2020, Beroni and Genscript performed an experiment to identify the most effective nanobodies. According to a recent paper published in Nature this September, nanobody-based therapy is an effective method that can be used to neutralize SARS-CoV-2 by blocking their entry into host cells mediated by an interaction between the spike glycoprotein and the angiotensin converting enzyme 2 (ACE2) receptor. To protect host cells from SARS-CoV-2 infection, Beroni chose different types of nanobodies as neutralizing candidates to determine which nanobodies could block the entry of SARS-CoV-2 with highest efficacy.

Nanobodies are single-domain antibodies. Compared with common antibodies, nanobodies are much smaller. Beroni aims at developing coronavirus-specific nanobodies as a treatment of COVID-19, which can be targeted on lung by aerosolization, rather than by intravenous drug administration. In order to find the most appropriate nanobodies in the field of affinity and efficacy, 12 types of nanobodies were evaluated as samples in the experiment.

In this experiment, ACE2 overexpression cells were used as target cells. The positive control was with ACE2-Fc added and negative control was with virus only. The samples’ potency on neutralization were evaluated by performing SARS-CoV-2 pseudovirus neutralization assay. Among the samples tested, one candidate nanobody demonstrated over 90% signal reduction against the pseudovirus. And another three candidate nanobodies achieved an approximate 50% inhabitation of pseudovirus infection. The results of the experiment show that positive control provided a significant neutralizing activity against the SARS-CoV-2 pseudovirus.

“We are encouraged by the experimental results. The results showed one type of nanobodies has been able to produce 90% virus signal reduction. This data will allow us to accelerate research and development timelines, and further advance preclinical research study. Simultaneously, we will continue to identify and test other types of nanobodies and make efforts to find the most proper ones in terms of affinity and efficacy,” commented Jacky Zhang, Chairman and CEO of Beroni Group. “Beroni are now utilizing nanobody technology to develop both detection and treatment solutions for COVID-19. We believe our technology has the potential to protect against coronavirus transmission and treat the complications of COVID-19.”