Ontology highlight
ABSTRACT: Background
Intranasal vaccination may induce protective local and systemic immune responses against respiratory pathogens. A number of intranasal SARS-CoV-2 vaccine candidates have achieved protection in pre-clinical challenge models, including ChAdOx1 nCoV-19 (AZD1222, University of Oxford / AstraZeneca).Methods
We performed a single-centre open-label Phase I clinical trial of intranasal vaccination with ChAdOx1 nCoV-19 in healthy adults, using the existing formulation produced for intramuscular administration. Thirty SARS-CoV-2 vaccine-naïve participants were allocated to receive 5 × 109 viral particles (VP, n=6), 2 × 1010 VP (n=12), or 5 × 1010 VP (n=12). Fourteen received second intranasal doses 28 days later. A further 12 received non-study intramuscular mRNA SARS-CoV-2 vaccination between study days 22 and 46. To investigate intranasal ChAdOx1 nCoV-19 as a booster, six participants who had previously received two intramuscular doses of ChAdOx1 nCoV-19 and six who had received two intramuscular doses of BNT162b2 (Pfizer / BioNTech) were given a single intranasal dose of 5 × 1010 VP of ChAdOx1 nCoV-19. Objectives were to assess safety (primary) and mucosal antibody responses (secondary).Findings
Reactogenicity was mild or moderate. Antigen-specific mucosal antibody responses to intranasal vaccination were detectable in a minority of participants, rarely exceeding levels seen after SARS-CoV-2 infection. Systemic responses to intranasal vaccination were typically weaker than after intramuscular vaccination with ChAdOx1 nCoV-19. Antigen-specific mucosal antibody was detectable in participants who received an intramuscular mRNA vaccine after intranasal vaccination. Seven participants developed symptomatic SARS-CoV-2 infection.Interpretation
This formulation of intranasal ChAdOx1 nCoV-19 showed an acceptable tolerability profile but induced neither a consistent mucosal antibody response nor a strong systemic response.Funding
AstraZeneca.
SUBMITTER: Madhavan M
PROVIDER: S-EPMC9550199 | biostudies-literature | 2022 Nov
REPOSITORIES: biostudies-literature
Madhavan Meera M Ritchie Adam J AJ Aboagye Jeremy J Jenkin Daniel D Provstgaad-Morys Samuel S Tarbet Iona I Woods Danielle D Davies Sophie S Baker Megan M Platt Abigail A Flaxman Amy A Smith Holly H Belij-Rammerstorfer Sandra S Wilkins Deidre D Kelly Elizabeth J EJ Villafana Tonya T Green Justin A JA Poulton Ian I Lambe Teresa T Hill Adrian V S AVS Ewer Katie J KJ Douglas Alexander D AD
EBioMedicine 20221010
<h4>Background</h4>Intranasal vaccination may induce protective local and systemic immune responses against respiratory pathogens. A number of intranasal SARS-CoV-2 vaccine candidates have achieved protection in pre-clinical challenge models, including ChAdOx1 nCoV-19 (AZD1222, University of Oxford / AstraZeneca).<h4>Methods</h4>We performed a single-centre open-label Phase I clinical trial of intranasal vaccination with ChAdOx1 nCoV-19 in healthy adults, using the existing formulation produced ...[more]