Omicron: Anti-covid drugs are powerful against Omicron, antibody therapies are less effective: study


WASHINGTON: Covid-19 is highly effective against current drugs Omicron Type of SARS-CoV-2 virus, according to laboratory studies.
However, available antibody therapies – usually given intravenously in hospitals – are significantly less effective against Omicron than previous types of the virus, the researchers said.
Laboratory tests also showed that some antibodies had completely lost their ability to inactivate omicrons at actual doses, they said.
“The bottom line is that we have countermeasures for Omicron treatment. That’s good news,” said the study’s lead author. Yoshihiro KawaokaTo University of Wisconsin-Madison In the US
“However, all of this is in laboratory studies. Whether this translates into humans, we do not yet know,” Kawaoka said.
The findings, published in the New England Journal of Medicine on Wednesday, support other studies that show that most available antibody treatments are less effective against omicron.
Medically available pills and antibodies were designed and tested before the researchers identified the Omicron variant, which is significantly different from previous versions of the virus.
When Omicron was identified, scientists feared that these differences, due to mutations in the viral genome, could reduce the effectiveness of drugs designed to treat the original version of the virus.
In laboratory experiments using non-human primate cells, colleagues from the National Institute of Infectious Diseases in Kawaoka and Japan tested a set of antibodies and antiviral therapies against the original strain of the Covid-19 virus and its leading strains.
They found that the US pharmaceutical company Merck’s pill Molnupiravir and the intravenous drug Ramdesivir were just as effective against Omicron as they were against previous viral strains.
Instead of testing PfizerThe Paxlovid pill, which is designed to be taken orally, was tested by the team on a related drug that is given intravenously.
The two drugs disrupt the same part of the viral machinery.
Researchers have found that the drug retains its efficacy against Omicron in intravenous form and this version is currently in clinical trials.
All four antibody treatments tested by the researchers were less effective than previous strains of the virus against Omicron.
Two treatments, Sotrovimab By GlaxoSmithKline And Evusheld, by AstraZeneca, retains little ability to neutralize the virus, according to researchers.
However, they need 3 to 100 times more drugs to neutralize Omicron than the previous version, they said.
The study also showed that two antibody treatments by Lily and Regeneron were unable to neutralize omicon at normal doses.
The researchers said the findings were expected to reflect how the Omicron variant differed from previous strains of the SARS-CoV-2 virus.
Omicron spikes contain dozens of mutations in proteins that are used by viruses to enter and infect cells.
Most antibodies were designed to bind and inactivate the original spike protein, and large changes in the protein may make antibodies less likely to attach to it.
In contrast, antiviral tablets target molecular machinery used by viruses to replicate themselves inside cells, the researchers said.
The Omicron variant has only a few modifications to this machinery, which makes it more likely that drugs will retain their ability to disrupt this replication process, they added.

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