Monoclonal antibodies, the drug sotrovimab can cause mutations of SARS CoV-2 more resistant to the same drug
Among monoclonal antibodies most used in the world to fight the Covid-19 there is the drug sotrovimabwhich has been shown to be particularly effective against variante Omicron. Its use, however, according to a study conducted by the Institute for Infectious Diseases of theSidney Universityin Australia, could lead to the emergence of new variants of the virus Sars CoV-2 more resistant to the same drug. It would be “the first time that a resistance to is discovered in the clinic sotrovimab. Although this is a rare event, this highlights the crucial role of surveillance, “say the experts.
Monoclonal antibodies, sotrovimab can cause more resistant mutations of the virus
Sotrovimab neutralizes Sars-CoV-2 mainly by blocking its entry into the host cell, binding to a particular region of the proteina Spike of the virus. The observational study conducted by the Australian researchers is published in the ‘New England Journal of Medicine‘and took place during the outbreak of Delta in 2021, analyzing the first 100 patients treated with the drug in western Sydney. Post-treatment follow-up was required in 23 patients, and of 8 of these who had remaining respiratory samples that could be used in genomic analysis, 4 developed resistant mutations. The data showed the persistence of Sars-CoV-2 vital in these patients after infusions of sotrovimab and the rapid development of mutations of the gene Spike associated in in vitro tests with drug resistance.
“We found that the virus can develop mutations within the patient several days after treatment with sotrovimabwhich reduces the effectiveness of this treatment by more than 100 times, “explained the lead author, Rebecca Rockettthe Sydney Institute for Infectious Diseases. Mutations within the drug’s target site were discovered by analyzing the entire viral genome sequence before and after treatment. These mutations were detected in a “small number of patients” 6-13 days after treatment. “Samples of resistant viruses – said the senior author of the research Vitali Sintchenko – could be easily cultured in the laboratory, an indicator that individuals who develop resistance can transmit this resistant virus to others. “