Open AccessNon‐neutralizing antibody responses following A(H1N1)pdm09 influenza vaccination with or without AS03 adjuvant system
Author(s) -
Friel Damien,
Co Mary,
Ollinger Thierry,
Salaun Bruno,
Schuind Anne,
Li Ping,
Walravens Karl,
Ennis Francis A.,
Vaughn David W.
Publication year - 2021
Publication title -
influenza and other respiratory viruses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.743
H-Index - 57
eISSN - 1750-2659
pISSN - 1750-2640
DOI - 10.1111/irv.12780
Subject(s) - adjuvant , vaccination , virology , medicine , antibody response , antibody , neutralizing antibody , immunology , covid-19 , infectious disease (medical specialty) , disease
Background Non‐neutralizing antibodies inducing complement‐dependent lysis (CDL) and antibody‐dependent cell‐mediated cytotoxicity (ADCC) activity may contribute to protection against influenza infection. We investigated CDL and ADCC responses in healthy adults randomized to receive either non‐adjuvanted or AS03‐adjuvanted monovalent A(H1N1)pdm09 vaccine (containing 15 µg/3.75 μg of hemagglutinin, respectively) on a 2‐dose schedule 21 days apart. Methods We conducted an exploratory analysis of a subset of 106 subjects having no prior history of A(H1N1)pdm09 infection or seasonal influenza vaccination enrolled in a previously reported study (NCT00985673). Antibody responses against the homologous A/California/7/2009 (H1N1) vaccine strain and a related A/Brisbane/59/2007 (H1N1) seasonal influenza strain were analyzed up to Day 42. Results Baseline seropositivity determined with hemagglutination inhibition (HI), CDL and ADCC antibody titers against viral strains was high; A/California/7/2009 (HI [40.4‐48.1%]; CDL [34.6‐36.0%]; ADCC [92.1‐92.3%]); A/Brisbane/59/2007 (HI [73.1‐88.9%]; CDL [38.0‐42.0%]; ADCC [86.8‐97.0%]). CDL seropositivity increased following vaccination with both adjuvanted and non‐adjuvanted formulations (A/California/7/2009 [95.9‐100%]; A/Brisbane/59/2007 [75.5‐79.6%]). At Day 21, increases in CDL and ADCC antibody geometric mean titers against both strains were observed for both formulations. After 2 doses of AS03‐adjuvanted vaccine, vaccine responses of 95.8% (≥9‐fold increase from baseline in CDL titers) and 34.3% (≥16‐fold increase from baseline in ADCC titers) were seen against A/California/7/2009; and 22.4% and 42.9%, respectively, against A/Brisbane/59/2007. Vaccine responses after 2 doses of the non‐adjuvanted vaccine were broadly similar. Conclusions Broadly comparable non‐neutralizing immune responses were observed following vaccination with non‐adjuvanted and AS03‐adjuvanted A(H1N1)pdm09 formulations; including activity against a related vaccine strain.