Omicron variant largely resistant to anti-viral medication

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New study also confirms lower effectiveness of vaccines and decreasing immunity among those who have recovered from the disease, but the booster vaccine helps.

The Omicron variant of coronavirus is spreading rapidly, and it appears as if some of the medical options available for treating those infected with the disease seem to be becoming less effective. The Omicron variant is resistant against many of the antibody-based medicines that have already been approved and have proven to be highly effective against earlier variants of the virus. This is the conclusion reached by a team of researchers including scientists from FAU. The researchers also confirmed that vaccinations are less effective against the new virus variant and that the antibodies generated by those who have recovered from the virus are also slower to react to Omicron. However, the study clearly indicates that vaccination does help and that the booster significantly increases protection against the Omicron variant as well. The findings have now been published in the journal ‘Cell’. (DOI 10.1016/j.cell.2021.12.032)

However, the study clearly indicates that vaccination does help and that the booster significantly increases protection against the Omicron variant as well.

The researchers from the German Primate Centre in Göttingen, Hannover Medical School, University of Göttingen Medical Center, Friedrich-Alexander-Universität Erlangen-Nürnberg and the German Centre for Infection Research in Braunschweig investigated cell cultures in Petri dishes to determine how efficiently antibodies can neutralise the Omicron variant. For their experiments, the researchers used harmless particles similar to the virus that are well suited to analysing how the virus enters our cells and how best to inhibit it. These particles were also equipped with the Omicron spike that the virus uses to attach to our cells.

The body creates antibodies after a vaccination or after being infected with the virus. Antibodies can also be produced using biotechnological methods and administered to individuals who have been infected with the disease. Antibodies bind to the virus and neutralise it, assisting the immune system in fighting off the infection.

Most antiviral medicines fail when it comes to Omicron

The most important, and most dramatic, conclusion reached by the study is that most of the therapeutic antibodies approved for treating Covid-19 are not effective against the Omicron variant.

Currently, combinations of the antibodies casirivimab and imdevimab as well as etesevimab and bamlanivimab are often used to treat Covid-19. Tests conducted by the team, however, indicated that these antibodies are largely ineffectual in treating Omicron. Only one of the tested antibodies, sotrovimab, was effective at inhibiting the Omicron spike. The researchers have come to the conclusion that this drug may now become a significant component in the treatment of individuals infected with the Omicron variant.

Unfortunately, the same also applies to those who are vaccinated or have recovered from the vaccine: antibodies that were highly effective against earlier variants of Covid-19 are less effective at inhibiting the Omicron variant. The results of this recent study confirm the results of earlier international investigations into the Omicron mutation.

Both two and three doses of the vaccine are less effective against Omicron than against earlier virus mutations. However, there is good news: the third dose of the vaccine, commonly known as the booster, generally provides a good level of protection.

The study clearly indicates that both two and three doses of the vaccine are less effective against Omicron than against earlier virus mutations. However, there is good news: the third dose of the vaccine, commonly known as the booster, generally provides a good level of protection. Even more protection is provided by mix and match vaccinations, in other words by administering different vaccines.

Even more protection is provided by mix and match vaccinations, in other words by administering different vaccines.

In the study, samples were investigated from individuals who only received the Biontech-Pfizer vaccine and from those who received a combination of the Biontech-Pfizer and AstraZeneca vaccines. ‘We are confident that our findings will also apply to those who have been vaccinated with Moderna or Moderna combinations,’ explains Prof. Dr. Hans-Martin Jäck, Head of the Molecular-Immunological Department at Universitätsklinikum Erlangen.

The researchers also investigated whether individuals who contracted the virus during the first wave of the coronavirus in Germany and produced antibodies as a result have any protection against the Omicron variant. The results were disappointing. Antibodies produced in response to infections with previous variants of the virus hardly have any effect on the Omicron spike. However, this will need to be investigated in more detail. It is still not known how the second line of defence in the immune system, i.e. the T-cells or macrophages that are also produced in response to an infection, will react to Omicron.

Conclusion

Researchers stress the importance of adjusting antibody therapies for Covid-19 and vaccines to cope with the Omicron variant. However, even though vaccines may be less effective against the Omicron variant, they are still strongly recommended, together with the commonly accepted protective measures against coronavirus. ‘We cannot say it often enough: Get vaccinated and get your booster,’ urges Professor Hans-Martin Jäck.

Contact:

Prof. Dr. Hans-Martin Jäck

Phone: +49 9131 85 35912

hans-martin.jaeck@fau.de.