Substantial Neutralization Escape of Omicron Variants – A Recent Study

Substantial Neutralization Escape by SARS-CoV-2 Omicron Variants BQ.1.1 and XBB.1 | NEJM

The study evaluated neutralizing antibody titers in individuals who received the BNT162b2 (Pfizer-BioNTech) mRNA vaccine and booster. After the booster, the neutralizing antibody titers to the BA.5, BF.7, BA.2.75.2, BQ.1.1, and XBB.1 variants were lower compared to the Wild Type WA1/2020 strain.

The findings suggested that the BQ.1.1 and XBB.1 variants, having the lowest titers, have a significantly higher ability to evade neutralizing antibodies compared to the BA.5 variant, even after mRNA boosting (bivalent or monovalent). The neutralizing antibody titers against BQ.1.1 and XBB.1 were dramatically lower than the WA1/2020 strain, indicating the reduced efficacy of current mRNA vaccines against these variants.

Overall, the emergence of multiple SARS-CoV-2 variants with the R346T mutation suggested convergent evolution, and the study highlighted the potential challenges in maintaining vaccine effectiveness against these evolving variants.

NAB-Sure now provides cell-free testing of Neutralizing Antibodies (NAb) against XBB.1.5 and BQ.1.1 variants, in addition to the previously released Wild Type and BA.4/5. NAB-Sure is ultrasensitive and can effectively be run on DBS samples, which makes it convenient for broad testing and can be used for longitudinal testing, population sero-surveillance, or retrospective studies.