Tuesday, July 19, 2022
Although COVID-19 booster vaccinations in adults cause high levels of neutralizing antibodies against the Omicron variant of SARS-CoV-2, antibody levels drop dramatically within 3 months, new clinical trial data shows . The findings, published today in Medicine Reports Unit, are from a study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. The trial was conducted by the NIAID Infectious Diseases Clinical Research Consortium.
In a “mix and match” clinical trial, researchers administered COVID-19 booster vaccines to adults in the United States who had already received a series of primary COVID-19 vaccinations as part of emergency use authorization. Some participants received the same vaccine as their primary series, and others received a different vaccine. Investigators then assessed immune responses over time. The results previously reported in the New England Journal of Medicine showed that all combinations of primary and booster vaccines resulted in increased levels of neutralizing antibodies in recipients.
In the new analysis, the researchers report that nearly all of the vaccine combinations evaluated (see table) elicited high levels of neutralizing antibodies against the Omicron BA.1 subline. However, antibody levels against Omicron were low in the group that received Ad26.COV2.S as both primary and booster vaccines. Additionally, immune responses to Omicron in all groups decreased significantly, with levels of neutralizing antibodies decreasing 2.4- to 5.3-fold three months after the boost. The Omicron BA.2.12.1 and BA.4/BA.5 sublines were respectively 1.5 and 2.5 times less sensitive to neutralization compared to the BA.1 subline, and 7.5 and 12 .4 times less sensitive compared to the ancestral line. Strain D614G. BA.5 is currently the dominant variant in the United States
The authors note that the results are consistent with real-world reports showing waning protection against SARS-CoV-2 infection during the Omicron wave in people who received a series of primary vaccines plus a booster shot. In addition, the immune response to Omicron sublines shows reduced sensitivity to these rapidly emerging subvariants. The data could be used to inform decisions about future vaccine schedule recommendations, including the need to boost variant vaccines.
The NIAID grants supporting this research were UM1AI48372, UM1AI148373, UM1AI148450, UM1AI148452, UM1AI148573, UM1AI148574, UM1AI148575, UM1AI148576, UM1AI148684, and UM1AI148689. NIAID Collaborative Influenza Vaccine Innovation Centers (CIVICs) contract 75N93019C00050 also provided support.
I am Lyke et al. Rapid Decline of Vaccine-Boosted Neutralizing Antibodies to SARS CoV-2 Variant Omicron. Medicine Reports Unit DOI: 10.1016/j.xcrm.2022.100679 (2022).
RL Atmar et al. Homologous and heterologous COVID-19 booster vaccinations. The New England Journal of Medicine DOI: 10.1056/NEJMoa2116414 (2022).
Dr. John H. Beigel, Associate Director of Clinical Research in NIAID’s Division of Microbiology and Infectious Diseases, is available to discuss the study.
To schedule interviews, please contact the News & Science Writing branch of NIAID, (301) 402-1663, firstname.lastname@example.org.
NIAID conducts and supports research—at the NIH, in the United States, and around the world—to study the causes of infectious and immune-mediated diseases and to develop better ways to prevent, diagnose, and treat these diseases. Press releases, fact sheets, and other NIAID-related materials are available on the NIAID website.
About the National Institutes of Health (NIH):The NIH, the country’s medical research agency, comprises 27 institutes and centers and is part of the US Department of Health and Human Services. The NIH is the primary federal agency that conducts and supports basic, clinical, and translational medical research, and studies the causes, treatments, and cures for common and rare diseases. For more information about the NIH and its programs, visit www.nih.gov.
NIH…Transforming Discovery into Health®