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Review
. 2021 Jun 15:603:120686.
doi: 10.1016/j.ijpharm.2021.120686. Epub 2021 May 6.

Nasal vaccination against SARS-CoV-2: Synergistic or alternative to intramuscular vaccines?

Mattia Tiboni  1 , Luca Casettari  1 , Lisbeth Illum  2
Affiliations
Review

Nasal vaccination against SARS-CoV-2: Synergistic or alternative to intramuscular vaccines?

Mattia Tiboni et al. Int J Pharm. .

Abstract

It is striking that all marketed SARS-CoV-2 vaccines are developed for intramuscular administration designed to produce humoral and cell mediated immune responses, preventing viremia and the COVID-19 syndrome. They have a high degree of efficacy in humans (70-95%) depending on the type of vaccine. However, little protection is provided against viral replication and shedding in the upper airways due to the lack of a local sIgA immune response, indicating a risk of transmission of virus from vaccinated individuals. A range of novel nasal COVID-19 vaccines are in development and preclinical results in non-human primates have shown a promising prevention of replication and shedding of virus due to the induction of mucosal immune response (sIgA) in upper and lower respiratory tracts as well as robust systemic and humoral immune responses. Whether these results will translate to humans remains to be clarified. An IM prime followed by an IN booster vaccination would likely result in a better well-rounded immune response, including prevention (or strong reduction) in viral replication in the upper and lower respiratory tracts.

Keywords: COVID-19; COVID-19 vaccines; Intramuscular COVID-19 vaccines; Intranasal COVID-19 vaccines; SARS-CoV-2; Vaccine immune responses.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

None
Graphical abstract
Fig. 1
Fig. 1
The structure of SARS-CoV-2 virion.
Fig. 2
Fig. 2
Pharyngeal lymphoid tissue of Waldeyer’s ring.
Fig. 3
Fig. 3
Antigen processing pathway of the NALT.
Fig. 4
Fig. 4
Vaccine platforms under development against SARS-CoV-2.
Fig. 5
Fig. 5
Timeline of the main adjuvants used in human vaccines.
See this image and copyright information in PMC

References

    1. Experts With One Big Claim: The Coronavirus Is Airborne - The New York Times [WWW Document]. URL https://www.nytimes.com/2020/07/04/health/239-experts-with-one-big-claim... (accessed 3.16.21).
    1. Aich P., Dwivedy Importance of innate mucosal immunity and the promises it holds. Int. J. Gen. Med. 2011;4:299. doi: 10.2147/ijgm.s17525. - DOI - PMC - PubMed
    1. Allen, A.C., Mills, K.H.G., 2014. Improved pertussis vaccines based on adjuvants that induce cell-mediated immunity. Expert Rev. Vaccines. DOI: 10.1586/14760584.2014.936391. - PubMed
    1. Altimmune Commences Enrollment in Phase 1 Clinical Trial of AdCOVIDTM -- a Needle-Free, Single-Dose Intranasal COVID-19 Vaccine Candidate – Altimmune [WWW Document]. URL https://ir.altimmune.com/news-releases/news-release-details/altimmune-co... (accessed 3.22.21).
    1. Alving, C.R., Peachman, K.K., et al., 2012. Adjuvants for human vaccines. Curr. Opin. Immunol. DOI: DOI: 10.1016/j.coi.2012.03.008. - PMC - PubMed