Washington: Omicron Coronavirus variants can avoid some, but not all, monoclonal antibodies are clinically used to prevent patients from developing severe Covid-19, according to a laboratory study.
Monoclonal antibodies are laboratory-made proteins that mimic the ability of the immune system to fight harmful pathogens such as viruses.
Some previous studies showed that the antibodies did not succeed in neutralizing Omicron.
The team led by researchers at Washington University, USA, tested five combinations of antibodies, including those found at the Vanderbilt University Medical Center (VUMC) in the US.
This study, which was recently published in the journal Nature Medicine, found antibodies, including those who were clinically used by biopharmaceutical companies, Regeneron and Eli Lilly, truly losing the ability to neutralize omicrons in cell culture.
Antibodies developed in VUMC have decreased neutralizing abilities, while as antibodies developed by VIR Biotechnology, the US, are very affected, the researchers found.
“Omicron escapes from recognition by several monoclonal antibodies that are being used for therapy,” said Director of James Crowe from the VIRCINE VACCENT CENTER, which his team found monoclonal antibodies in VUMC which was then optimized by Astrazeneca to be a combination of antibodies called Evusheld.
“Precursor antibodies from Sotrovimab VIR biotechnology, and prophylaxis antibodies in Evusheld maintain substantial activity even though it is reduced,” Crowe said, coauthor from research papers.
Although this data shows that some monoclonal antibodies in clinical use may maintain benefits, more experiments are needed to support this conclusion and inform clinical decisions, the author said.
The loss of neutralization capabilities in Omicron is caused by more than 30 mutations in the protein “surge”, the target of antibodies on the surface of the virus that helps enter and infect cells.
The loss of inhibitory activity in this study is consistent with the observation that the antibody response produced after vaccination or natural infection also loses substantial inhibitory activity against Omicron, the researchers said.
The findings can explain some of the increase in symptomatic infections caused by omicron variants in people who have previously been vaccinated, they said.
The study “is good news, because we still have antibody drugs at least we can use for each indication, prevention or therapy,” Crowe added.
Identification and use of monoclonal antibodies that are widely and the neutralizing potential that targets the most conservative and most impossible to mutate from the surge protein needed to protect against the omicron and future variants, the researchers added.