Evidence map›Paper›PMID 40006716›Full record

ArticleVaccines2025

Efficacy of Inactivated Bivalent SARS-CoV-2 Vaccines Targeting Ancestral Strain (ERAGEM), Delta, and Omicron Variants.

Busra Kaplan, Shaikh Terkis Islam Pavel, Muhammet Ali Uygut, Merve Tunc, Yesari Eroksuz, Ilhami Celik, Esma Eryilmaz Eren, Gulay Korukluoglu, Ates Kara, Aykut Ozdarendeli and 1 more

Abstract read
In one paragraph

Article in Vaccines, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Busra KaplanVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.ORCID 0000-0002-2029-6270
Shaikh Terkis Islam PavelVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.ORCID 0000-0002-7178-0943
Muhammet Ali UygutVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.ORCID 0000-0002-8794-341X
Merve TuncVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.
Yesari EroksuzDepartment of Pathology, Faculty of Veterinary Medicine, Fırat University, 23100 Elazig, Türkiye.
Ilhami CelikDepartment of Infectious Disease and Clinical Microbiology, University of Health Sciences, 38080 Kayseri, Türkiye.ORCID 0000-0002-2604-3776
Esma Eryilmaz ErenDepartment of Infectious Diseases and Clinical Microbiology, Kayseri City Education and Research Hospital, 38080 Kayseri, Türkiye.
Gulay KorukluogluDepartment of Clinical Microbiology, University of Health Sciences, Ankara Bilkent City Hospital, 06800 Ankara, Türkiye.ORCID 0000-0001-7625-6350
Ates KaraPediatric Infectious Department, Faculty of Medicine, Hacettepe University Hospitals, 06230 Ankara, Türkiye.ORCID 0000-0002-1654-3232
Aykut OzdarendeliVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.
Hazel YetiskinVaccine Research and Development Institute, Erciyes University, 38280 Kayseri, Türkiye.ORCID 0000-0003-0813-791X

Funding

This research was funded by the Council of Higher Education (YÖK) under the Research Universities Support Program (ADEP) (with grand ID 12160 and project code TSAÜ-2022-12160).
6 · The paper itself

Abstract

BACKGROUND/

objectivesThe rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the emergence of variants with enhanced transmissibility and immune evasion, challenging existing vaccines. This study aimed to evaluate the immunogenicity and protective efficacy of inactivated bivalent vaccine formulations incorporating the ancestral SARS-CoV-2 strain (ERAGEM) with either Delta or Omicron (BA.5) variants.

methodsBivalent vaccine formulations were prepared using beta-propiolactone-inactivated SARS-CoV-2 antigens and administered to K18-hACE2 transgenic mice. Following prime and booster immunizations, neutralizing antibody titers and viral loads were assessed through ELISA, microneutralization assays, and quantitative PCR. Mice were challenged with the respective variants, and the survival rates, temperature, and body weight changes were monitored for 21 days.

resultsBoth vaccine formulations elicited significant increases in neutralizing antibody titers post-booster immunization. The ERAGEM + Delta group demonstrated geometric mean titers (GMTs) of 6938.1 and 4935.0 for the ancestral and Delta variants, respectively, while the ERAGEM + Omicron (BA.5) group achieved GMTs of 16,280.7 and 24,215.9 for the ancestral and Omicron (BA.5) variants. Complete survival (100%) was observed in all the vaccinated groups post-challenge, with no detectable viral titers in the lungs and substantial reductions in the nasal turbinate viral loads compared to the unvaccinated controls.

conclusionsThe bivalent inactivated vaccines demonstrated strong immunogenicity and complete protection against severe disease in preclinical models. These findings indicate the potential of bivalent vaccine strategies in addressing antigenic diversity and preparing for future pandemics caused by rapidly evolving pathogens.

Indexed as

bivalent vaccineimmune responseinactivated vaccinepandemic preparednessSARS-CoV-2

Identifiers

PMID40006716
PMCPMC11861512

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.