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Randomized Controlled Trial
. 2024 Dec:149:107260.
doi: 10.1016/j.ijid.2024.107260. Epub 2024 Oct 10.

Randomised immunogenicity trial comparing 2019-2020 recombinant and egg-based influenza vaccines among frequently vaccinated healthcare personnel in Israel

Ashley L Fowlkes  1 , Alon Peretz  2 , David Greenberg  3 , Avital Hirsch  4 , Emily T Martin  5 , Min Z Levine  6 , Laura Edwards  7 , Sarah Radke  8 , Adam S Lauring  5 , Jill M Ferdinands  6 , Chao Zhang  6 , Young M Yoo  6 , Jacob Dreiher  3 , Gabriella Newes-Adeyi  7 , Eduardo Azziz-Baumgartner  6 , Alicia M Fry  6 , Arnold S Monto  5 , Ran Balicer  4 , Mark G Thompson  6 , Mark A Katz  4
Affiliations
Randomized Controlled Trial

Randomised immunogenicity trial comparing 2019-2020 recombinant and egg-based influenza vaccines among frequently vaccinated healthcare personnel in Israel

Ashley L Fowlkes et al. Int J Infect Dis. 2024 Dec.

Abstract

Objectives: Trivalent inactivated influenza vaccine effectiveness was low in a prospective cohort of healthcare personnel (HCP) in Israel from 2016 to 2019. We conducted a randomised immunogenicity trial of quadrivalent recombinant influenza vaccine (RIV4) and standard-dose inactivated influenza vaccine (IIV4) among frequently and infrequently vaccinated previous cohort participants.

Methods: From October 2019 to January 2020, we enrolled and randomly allocated HCP from two Israeli hospitals to receive IIV4 or RIV4. Hemagglutination inhibition (HAI) antibody titres against 2019-2020 vaccine reference influenza viruses were compared between vaccine groups using geometric mean titre (GMT) ratios from sera collected one-month post-vaccination and by frequency of vaccination in the past 5 years (>2 vs ≤2).

Results: Among 415 HCP, the GMT ratio comparing RIV4 to IIV4 was 2.0 (95% confidence interval [CI] 1.7-2.7) for A(H1N1)pdm09, 1.6 (95% CI: 1.3-1.9) for A(H3N2), 1.8 (95% CI: 1.4-2.2) for B(Yamagata), and 1.1 (95% CI: 0.9-1.4) for B(Victoria). Similarly, RIV4 elicited higher HAI titres than IIV4 against all 2019-2020 vaccine reference viruses except B(Victoria) among infrequently and frequently vaccinated HCP (lower bound of GMT ratio 95% CIs ≥1.0).

Conclusion: RIV4 had improved immunogenicity for influenza vaccine strains among both infrequent and frequent vaccinees compared to standard-dose IIV4.

Clinical trials registration: NCT04523324.

Keywords: Flublok; Healthcare personnel; Immunogenicity; Influenza vaccine; Recombinant.

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Conflict of interest statement

Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Adam Lauring: Roche steering committee for a clinical trial of Baloxivir; grants/contracts from NIAID, CDC, Burroughs Wellcome Fund, Flu Lab. David Greenberg: Received grants from: Merck Sharp & Dohme and Abbvie, Sanofi unrelated to influenza vaccine; Scientific consultant for Pfizer, Abbvie, Beyond Air, Astra Zeneca, Enox Biopharma, GlaxoSmithKline, and Merck Sharp & Dohme, Beyond Air, Beyond Cancer on subjects unrelated to influenza vaccine; Received honoraria as a speaker from Pfizer, Abbvie, Merck Sharp & Dohme, Sanofi, Astra Zeneka unrelated to the area of this influenza vaccine; Shareholder of Beyond Air, Beyond Cancer. Emily T. Martin: grants/contracts from NIH, Merck, US CDC.

Figures

Figure 1.
Figure 1.
CONSORT diagram of healthcare personnel enrolled in a randomized, controlled immunogenicity trial of quadrivalent recombinant-hemagglutinin and egg-grown influenza vaccines, Israel, 2019-2020. Among 1,577 participants of a previous cohort study, 1,240 healthcare personnel were reached; 656 declined participation, 7 were not eligible due to no longer being employed in the recruiting hospital, not currently working, or pregnant, and 4 consented, but did not complete enrollment.
Figure 2.
Figure 2.
Geometric mean titer ratios comparing humoral antibody responses 1-month post-vaccination with 2019-2020 quadrivalent recombinant and egg-based influenza vaccines among all participants (a), and by frequency of influenza vaccination over the past 5 seasons (b) and vaccination during the prior 2018–2019 season (c). Geometric mean titer ratios were calculated by linear mixed model or generalized estimating equation (GEE for GMT ≥160) after controlling for age, hospital, and immunocompromised status. Frequency of vaccinations were categorized as frequent and infrequent: frequently vaccinated, defined as receiving influenza vaccine in 3–5 of the past 5 seasons, compared with those infrequently vaccinated, defined as receiving influenza vaccine in ≤2 of the past 5 seasons.
See this image and copyright information in PMC

References

    1. Advisory Committee on Immunization Practices, Centers for Disease Control and PreventionImmunization of health-care personnel: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2011;60(RR-7):1–45. - PubMed
    1. Cherian T, Morales KF, Mantel C, Lambach P. Independent Expert Advisory Group for Health Worker Influenza Vaccination. Factors and considerations for establishing and improving seasonal influenza vaccination of health workers: Report from a WHO meeting, January 16-17, Berlin, Germany. Vaccine 2019;37(43):6255–61. - PMC - PubMed
    1. Imai C, Toizumi M, Hall L, Lambert S, Halton K, Merollini K. A systematic review and meta-analysis of the direct epidemiological and economic effects of seasonal influenza vaccination on healthcare workers. PLoS One 2018;13(6):e0198685. - PMC - PubMed
    1. Leung VKY, Carolan LA, Worth LJ, Harper SA, Peck H, Tilmanis D, et al. Influenza vaccination responses: evaluating impact of repeat vaccination among health care workers. Vaccine 2017;35(19):2558–68. - PubMed
    1. Thompson MG, Naleway A, Fry AM, Ball S, Spencer SM, Reynolds S, et al. Effects of repeated annual inactivated influenza vaccination among healthcare personnel on serum hemagglutinin inhibition antibody response to A/Perth/16/2009 (H3N2)-like virus during 2010-11. Vaccine 2016;34(7):981–8. - PMC - PubMed

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