At the end of last week, American drugmaker Pfizer Inc along with its partner, German biotech company BioNTech SE, announced that their Omicron vaccine (against the BA.4/5 subvariants) produced a strong immune system response in older people in a month, exceeding the response of the original vaccine.
According to Reuters, the companies were able to record that one month after a booster dose of the vaccine, the number of antibodies against BA.4/5 strains in 36 individuals over the age of 55 increased by nearly four times.
Within the age group of 18–55 years, the new bivalent shot also produced an active immune reaction against the aforementioned Omicron’s strains. However, the results of this group were compared not to the original vaccine response, but to the pre-booster levels.
Nevertheless, some experts emphasized that an increase in antibodies isn't always directly correlated with the level of a person’s protective immunity, therefore, these results don’t demonstrate the effectiveness of the booster shot.
Thus, Paul Offit, an infectious disease specialist and director of vaccine education center at the Children's Hospital of Philadelphia, noted that Pfizer and BioNTech’s data don’t confirm the clinical significance of the fourfold increase in antibodies in individuals.
Government data stated that as of November 2, 2022, more than 26 million American people had received the new Omicron shot, within which 3.4 million had gotten it over the previous week.