From which variants does Pfizer’s updated vaccine protect Omicron 4 and 5?
Pfizer has released the results of its bivalent vaccine adapted to Omicron 4 and 5 compared to subvariants BA.4.6, BA.2.75.2, BQ.1.1 and XBB.1. Here's what transpired
After Moderna announced that both of its upgraded bivalent boosters showed 'solid' neutralizing activity against the BQ.1.1 subvariant, Pfizer and BioNTech have now also published data on the response of their Omicron 4 and 5-adapted vaccine against the latest emerging sub-lineages – including BA.4.6, BA.2.75.2, BQ.1.1 and XBB.1.
DATA ANALYZED
One month after administration of a booster with the bivalent vaccine adapted to Omicron 4 and 5 or with the 'old' vaccine (based only on the parent strain of the virus) – as a fourth dose, in adults aged 55 years and older – bioRxiv neutralization data has been published.
THE RESULTS
The analysis found that the booster with the bivalent vaccine produced a greater increase in neutralizing antibody titres for all Omicron sub-lineages tested compared to the original vaccine, regardless of prior SARS-CoV-2 infection status.
'OLD' VACCINE VS VACCINE UPDATED TO OMICRON 4 AND 5
Notably, with a booster dose of the bivalent upgraded to Omicron 4 and 5, neutralizing antibodies against BA.4.6 increased 11.1-fold, while those against BA.2.75.2, BQ.1.1 and XBB.1 increased by 6.7 times, 8.7 times and 4.8 times, respectively.
On the other hand, in the case of a booster with the 'old' vaccine, the titers of neutralizing antibodies against BA.4.6, BA.2.75.2, BQ.1.1 and XBB.1 increased by 2.3 times, 2.1 times, respectively , 1.8 times and 1.5 times.
Furthermore, the two pharmaceutical companies recall that these results are similar to recent clinical data demonstrating that the bivalent booster adapted to Omicron 4 and 5 causes a 13-fold increase in BA.4/BA.5 neutralizing titers compared to pre-booster levels in subjects aged 55 and over, with a 4 times higher response compared to the 'old' vaccine.
WHICH VARIANTS ARE CIRCULATING IN ITALY?
According to the latest flash survey of the Istituto Superiore di Sanità (ISS), as of November 8, in Italy the Omicron variant had an estimated prevalence of 99.8%, with the BA.5 subvariant largely predominant and a share of Omicron recombinants /omicron consisting of only XBB.1, equal to 2.4% and now renamed online Gryphon.
This is a machine translation from Italian language of a post published on Start Magazine at the URL https://www.startmag.it/sanita/da-quali-varianti-protegge-il-vaccino-aggiornato-a-omicron-4-e-5-di-pfizer/ on Tue, 22 Nov 2022 10:01:29 +0000.