New COVID vaccine induces good antibody response against mutated virus variants, study finds

Researchers from Karolinska Institutet and Danderyd Hospital followed recipients of the new updated COVID-19 vaccine and analyzed the antibody response against different variants of SARS-CoV-2. The results show a surprisingly strong response to the now dominant and highly mutated omicron variants.

The ongoing COMMUNITY study, which launched in spring 2020 with regular testing of 2,149 Danderyd Hospital staff, recently released results from this fall’s portion of the study.

Twenty-four participants were registered in this study, the majority of whom were over 64 years old and had already received four or five doses of vaccine. The article has been accepted for publication in the journal Lancet infectious diseasesand is accessible before publication on the pre-print server, bioRxiv.

Target exclusively omicron

Previous COVID-19 vaccine updates included both the original SARS-CoV-2 variant and the omicron. However, they triggered a much stronger antibody response against the first than against the second. Omicron variants are now globally dominant, and the sharp increase in the Omicron XBB variant and its subvariants has prompted the development of vaccines against these strains. However, other variants have since taken over, including the highly mutated BA.2.86, and scientists are unsure whether the new vaccine also protects against these.

The results of this study now show that the updated COVID-19 vaccine yields a 10-fold increase in antibodies not only against XBB, but also against newer, more mutated strains, such as BA.2.86.

“It is good to see that the new updated vaccine induces such a broad antibody response,” says Charlotte Thålin, researcher at Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, MD at Danderyd Hospital and chief researcher of the COMMUNITY study on which the results are based.

“Previous updates failed to shift the response to the omicron and new variants because they were adapted to the original virus. The broad response we are currently seeing is likely because the new vaccine targets only the omicron, which differs greatly from the original virus.”

Surprisingly effective

“We are seeing a stronger increase than we expected in neutralizing antibodies against all the new variants that we had tested,” says the paper’s first author, Ulrika Marking, a doctoral student at Karolinska Institutet, the department of clinical sciences, Hospital Danderyd.

“This strongly suggests that the new vaccine also provides cross-protection against new variants and supports the recommendation that older adults and those in the risk group for influenza and COVID-19 should get vaccinated.”

The COMMUNITY study is being conducted as a collaboration between Danderyd Hospital, Karolinska Institutet, the Swedish Public Health Agency, Uppsala University and SciLifeLab.

Small changes in the scientific article can be made before final publication in Lancet infectious diseases.