Author:
Abdoli Asghar,Jamshidi Hamidreza,Taqavian Mohammad,Baghal Mehdi Lari,Jalili Hasan
Abstract
AbstractOmicron variant (B.1.1.529) is able to escape from naturally acquired and vaccine-induced immunity, which mandates updating the current COVID-19 vaccines. Here, we investigated and compared the neutralising antibody induction of the ancestral variant-based BIV1-CovIran vaccine, the Omicron variant-based BIV1-CovIran Plus vaccine, and the novel bivalent vaccine candidate, BBIV1-CovIran, against the Omicron and ancestral Wuhan variants on the rat model. After inactivating the viral particles, the viruses were purified and formulated. Bivalent vaccines were a composition of 2.5 µg (5 µg total) or 5 µg (10 µg total) doses of each ansectral-based and Omicron-based monovalent vaccine. Subsequently, the potency of the monovalent and bivalent vaccines was investigated using the virus neutralisation test (VNT). The group that received three doses of the Omicron-specific vaccine demonstrated neutralisation activity against the Omicron variant with a geometric mean titer of 337.8. However, three doses of the Wuhan variant-specific vaccine could neutralise the Omicron variant at a maximum of 1/32 serum dilution. The neutralisation activity of the Omicron-specific vaccine, when administered as the booster dose after two doses of the Wuhan variant-specific vaccine, was 100% against the Omicron variant and the Wuhan variant at 1/64 and 1/128 serum dilution, respectively. Three doses of 5 µg bivalent vaccine could effectively neutralise both variants at the minimum of 1/128 serum dilution. The 10 µg bivalent vaccine at three doses showed even higher neutralisation titers: the geometric mean of 388 (95% CI 242.2–621.7) against Omicron and 445.7 (95% CI 303.3–655.0) against Wuhan. It is shown that the candidate bivalent and Omicron-specific vaccines could elicit a potent immune response against both Wuhan-Hu-1 and Omicron BA.1 variants.
Funder
Shifa-Pharmed Industrial Group
Publisher
Springer Science and Business Media LLC
Reference36 articles.
1. Collie, S., Champion, J., Moultrie, H., Bekker, L.-G. & Gray, G. Effectiveness of BNT162b2 vaccine against Omicron variant in South Africa. N. Engl. J. Med. 386, 494–496 (2021).
2. Tseng, H. F. et al. Effectiveness of mRNA-1273 against SARS-CoV-2 Omicron and Delta variants. Nat. Med. 28, 1063–1071 (2022).
3. Bok, K., Sitar, S., Graham, B. S. & Mascola, J. R. Accelerated COVID-19 vaccine development: Milestones, lessons, and prospects. Immunity 54, 1636–1651 (2021).
4. World Health Organization. Weekly epidemiological update on COVID-19. (2023).
5. WHO. Interim Statement on COVID-19 vaccines in the context of the circulation of the Omicron SARS-CoV-2 Variant from the WHO Technical Advisory Group on COVID-19 Vaccine Composition (TAG-CO-VAC), accessed 2 February 2022; https://www.who.int/news/item/11-01-2022-interim-statement-on-covid-19-vaccines-in-the-context-of-the-circulation-of-the-omicron-sars-cov-2-variant-from-the-who-technical-advisory-group-on-covid-19-vaccine-composition (2022)