Researchers at Karolinska Institutet and Danderyd Hospital have conducted a thorough analysis of the antibody response to various SARS-CoV-2 variants among recipients of the updated COVID-19 vaccine. Surprisingly, the results reveal a robust immune response, particularly against the dominant and highly mutated omicron variants.
The ongoing COMMUNITY study, initiated in the spring of 2020 with regular testing of 2,149 Danderyd Hospital staff members, recently released findings from the autumn phase of the study. The research included 24 participants, predominantly aged over 64, who had received four or five previous vaccine doses. Accepted for publication in The Lancet Infectious Diseases, the article is available before official release on the pre-print server, bioRxiv.
Exclusively targets omicron
Previous iterations of the COVID-19 vaccine encompassed both the initial SARS-CoV-2 variant and omicron, yet they elicited a notably stronger antibody response against the former compared to the latter. With omicron variants now prevailing globally, the emergence of the omicron XBB variant and its sub-variants prompted vaccine development. However, the landscape evolved with the ascent of other variants, notably the highly mutated BA.2.86. Uncertainty loomed over the efficacy of the updated vaccine against these recent strains.
The latest study outcomes dispel some of that uncertainty, revealing a tenfold surge in antibodies conferred by the updated COVID-19 vaccine. This heightened response extends not only to XBB but also encompasses newer and more mutated strains, such as BA.2.86.
Charlotte Thålin, a researcher at Karolinska Institutet and head researcher of the COMMUNITY study, emphasizes the significance of the broad antibody response observed. She notes, “It’s reassuring to observe that the updated vaccine induces such a comprehensive antibody response. Unlike previous updates, which struggled to pivot the response toward omicron and new variants, the efficacy we’re witnessing now is likely attributable to the new vaccine’s focused targeting of omicron, which diverges significantly from the original virus.”
Unexpectedly effective
Ulrika Marking, the first author of the paper and a doctoral student at Karolinska Institutet, highlights the encouraging trend observed: “We’re witnessing a more pronounced increase than anticipated in the neutralizing antibodies against all the newly tested variants. This strongly implies that the updated vaccine offers cross-protection against these variants, reinforcing the recommendation for older individuals and those in high-risk groups for influenza and COVID-19 to receive vaccination.”
The collaborative COMMUNITY study involves contributions from Danderyd Hospital, Karolinska Institutet, the Swedish Public Health Agency, Uppsala University, and SciLifeLab.
It’s worth noting that minor adjustments may occur in the scientific article before its final publication in The Lancet Infectious Diseases.
Source: Karolinska Institutet