Study suggests 3 Pfizer vaccine doses may protect against OmicronToday a study from Germany published in Science shows three doses of the Pfizer-BioNTech COVID-19 vaccine raised antibody levels against the highly transmissible Omicron (B.1.1.529) variant.The study was based on sera from 51 participants, which was challenged with Wuhan, Beta, Delta, or Omicron pseudoviruses.
The participants had received either two or three doses of the Pfizer vaccine. Though neutralizing antibodies are just one measure of vaccine effect and don't demonstrate effectiveness per se, the authors say they can be strongly predictive of the degree of immune protection against symptomatic SARS-CoV-2 infection.Twenty-one days after the primary two-dose series, sera samples had a significant reduction in neutralizing activity against Omicron; after two doses, geometric mean neutralization titers (GMT) against Omicron pseudovirus were 22.8-fold lower than the Wuhan reference pseudovirus, and 20 out of 32 immune sera displayed no detectable neutralizing activity against Omicron.But within 4 weeks of a third dose, Omicron-neutralizing titers had increased 23-fold compared with two doses."Our data show that a third BNT162b2 [Pfizer] dose effectively neutralizes Omicron at a similar order of magnitude as was observed after two doses of BNT162b2 against wild-type SARS-CoV-2," the authors concluded. Jan 18 Science studyFewer racial minorities given monoclonal antibodies to treat COVID-19Analysis of data from 41 healthcare systems participating in the US National Patient-Centered Clinical Research Network shows that monoclonal antibodies (mAbs) were administered to Black, Asian, Hispanic, and other minority-race COVID-19 outpatients at lower rates than