A new study by researchers from the University of Kent
and the Goethe-University Frankfurt shows that the SARS-CoV-2 Omicron variant
is less effective than Delta at blocking a cellular defence mechanism against
viruses, the so-called “interferon response". Moreover, cell culture findings
indicate that eight important COVID-19 drugs and drug candidates remain
effective against Omicron.
FRANKFURT/CANTERBURY. The
SARS-CoV-2 Omicron variant causes less severe disease than Delta although it is
better at escaping immune protection by vaccinations and previous infections.
The reasons for this have so far remained elusive.
A new study by a research team with scientists
from the University of Kent and the Goethe-University Frankfurt has now shown
that Omicron variant viruses are particularly sensitive to inhibition by the
so-called interferon response, an unspecific immune response that is present in
all body cells. This provides the first explanation of why COVID-19 patients
infected with the Omicron variant are less likely to experience severe disease.
The cell culture study also showed that
Omicron viruses remain sensitive to eight of the most important antiviral drugs
and drug candidates for the treatment of COVID-19. This included EIDD-1931 (active metabolite of
molnupiravir), ribavirin, remdesivir, favipravir, PF-07321332 (nirmatrelvir,
active ingredient of paxlovid), nafamostat, camostat, and aprotinin.
Prof Martin Michaelis, School of
Bioscience, University of Kent, said: “Our study provides for the first time an
explanation, why Omicron infections are less likely to cause severe disease.
Obviously, Omicron can in contrast to Delta not effectively inhibit the host
cell interferon immune response.“
Prof. Jindrich Cinatl, Institute of
Medical Virology at the Goethe-University, added: “Although cell culture
experiments do not exactly recapitulate the more complex situation in a
patient, our data provide encouraging evidence that the available antiviral
COVID-19 drugs are also effective against Omicron.“
Publication: Denisa Bojkova, Marek
Widera, Sandra Ciesek, Mark N. Wass, Martin Michaelis, Jindrich Cinatl jr. Reduced interferon antagonism but similar
drug sensitivity in Omicron variant compared to Delta variant SARS-CoV-2
isolates. In: Cell. Res. (2022) https://doi.org/10.1038/s41422-022-00619-9
Further
information: The drug aprotinin inhibits entry of
SARS-CoV-2 in host cells (23rd Nov 2020)
https://aktuelles.uni-frankfurt.de/englisch/the-drug-aprotinin-inhibits-entry-of-sars-cov2-in-host-cells/
Scientific
Contact:
Professor Jindrich Cinatl
Institute of MedicalVirology
Universitätsklinikum Frankfurt
Phone: +49 (0) 69 6301-6409
cinatl@em.uni-frankfurt.de
Professor Martin Michaelis
School of Biosciences
University of Kent
Phone: +44 (0)1227 82-7804
Mobile: +44 (0)7561 333 094
m.michaelis@kent.ac.uk
