Immunogenicity and Safety of a Combined Intramuscular/Intranasal Recombinant Spike Protein COVID-19 Vaccine (RCP) in Healthy Adults Aged 18 to 55 Years Old: A Randomized, Double-Blind, Placebo-Controlled, Phase I Trial.
Vaccines (Basel)
; 11(2)2023 Feb 16.
Article
in English
| MEDLINE | ID: covidwho-2240318
ABSTRACT
Objectives:
This study aimed to determine the safety and immunogenicity of a combined intramuscular/intranasal recombinant spike protein COVID-19 vaccine (RCP).Methods:
We conducted a randomized, double-blind, placebo-controlled, phase I trial. Three vaccine strengths were compared with an adjuvant-only preparation. It included two intramuscular and a third intranasal dose. Eligible participants were followed for adverse reactions. Specific IgG, secretory IgA, neutralizing antibodies, and cell-mediated immunity were assessed.Results:
A total of 153 participants were enrolled (13 sentinels, 120 randomized, 20 non-randomized open-labeled for IgA assessment). No related serious adverse event was observed. The geometric mean ratios (GMRs) and 95% CI for serum neutralizing antibodies compared with placebo two weeks after the second injection were 5.82 (1.46-23.13), 11.12 (2.74-45.09), and 20.70 (5.05-84.76) in 5, 10, and 20 µg vaccine groups, respectively. The GMR for anti-RBD IgA in mucosal fluid two weeks after the intranasal dose was 23.27 (21.27-25.45) in the 10 µg vaccine group. The humoral responses were sustained for up to five months. All vaccine strengths indicated a strong T-helper 1 response.Conclusion:
RCP is safe and creates strong and durable humoral and cellular immunity and good mucosal immune response in its 10 µg /200 µL vaccine strengths. Trial registration IRCT20201214049709N1.
Full text:
Available
Collection:
International databases
Database:
MEDLINE
Type of study:
Experimental Studies
/
Randomized controlled trials
Topics:
Vaccines
Language:
English
Year:
2023
Document Type:
Article
Affiliation country:
Vaccines11020455
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