Pfizer released, this Saturday (25), promising data on the adapted version of the Covid-19 vaccine specific to the Ômicron variant of the new coronavirus.
The drugmaker is developing two vaccine candidates, one monovalent and one bivalent. While one is a combination of Pfizer’s vaccine, the other is targeted at the Spike protein of the BA.1 lineage of Ômicron.
The press release presents information on safety, tolerability and ability to induce an immune response (immunogenicity).
According to Pfizer, data from the Phase 2 and 3 study indicated that a booster dose of both adapted vaccine candidates elicited a substantially greater immune response against BA.1 from Omicron BA.1 compared to the current vaccine. Robust immune response was observed at two dose levels of 30 and 60 micrograms.
“As we’ve said since the early days of the pandemic, we will follow the science and adapt our own approaches as needed to help address Covid-19 as the virus evolves,” said Albert Bourla, president and CEO of Pfizer, in a statement.
According to Pfizer, the data identified in the studies will be discussed with the scientific community and health authorities for the introduction of a booster adapted to Ômicron as soon as there is authorization from regulatory bodies.
“The data demonstrates the ability of our Omicron-adapted monovalent and bivalent vaccine candidates to significantly improve neutralization responses of specific variant antibodies,” said researcher Ugur Sahin, CEO and co-founder of BioNTech.
Omicron has newly evolved substrains that outperform BA.1 and exhibit a tendency to increase the potential for immune escape.
Studies
The Omicron-adapted vaccine candidates evaluated in the Phases 2 and 3 study in 1,234 participants 56 years of age and older elicited substantially higher neutralizing antibody responses against Omicron’s BA.1 when compared to the current vaccine.
Demonstration of superiority over Ômicron and safety are regulatory requirements for the potential emergency use authorization of a variant-adapted vaccine. The pre-specified criterion for superiority was measured by the ratio of neutralizing geometric mean titers.
One month after administration, a booster dose of the Δmicron-adapted monovalent candidates (30 µg and 60 µg) increased neutralizing antibodies against BA.1 by 13.5 and 19.6-fold above pre-dose levels. reinforcement. While a boost of the adapted bivalent candidates conferred a 9.1 and 10.9 fold increase in antibodies.
According to Pfizer, both Omicron-adapted vaccine candidates were well tolerated in study participants.
In a SARS-CoV-2 live virus neutralization assay tested on sera from participants over 56 years of age, the sera efficiently neutralized the BA.4 and BA.5 subvariants with titers approximately 3-fold lower than BA.1. Additional data on the effect on these subvariants will be collected in the coming weeks.
Pfizer said the results are being shared with the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) ahead of upcoming discussions with the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) in 28 June and with the International Coalition of Medicines Regulatory Authorities (ICMRA) on 30 June.
Source: CNN Brasil
