Abstract
BACKGROUND. High-dose influenza vaccine, containing four times more antigen than standard-dose, is recommended for people aged ≥ 65 years, but there is a knowledge gap surrounding its effect in people with HIV (PWH), who remain more vulnerable to serious influenza infections than people without HIV (PWoH) despite virological suppression. The primary goal of this study was to assess whether high-dose improves antibody responses in PWH, with a particular focus on older PWH. METHODS. We conducted a study to assess antibody responses to sequential high- versus standard-dose influenza vaccination in PWH. Young (18-40 years) PWoH (n=55) and PWH (n=37); and older (≥ 60 years) PWoH (n=72) and PWH (n=67) received standard-dose during the 2020-2024 seasons and 123 participants, including 41 older PWH, received high-dose the consecutive season. All PWH were virologically suppressed on ART. Hemagglutination inhibition (HAI) titer and HA-specific IgG were analyzed at 0- to 180-days post-vaccination (dpv); T cell activation-induced responses were assessed by flow cytometry. RESULTS. All groups mounted significant HAI and IgG responses to all vaccine antigens at 28 dpv, after standard- and high-dose vaccination. Responses to A/H1N1 were lower in magnitude and durability in older PWH compared to young PWoH following standard-dose and were not boosted with high-dose, whereas high-dose enhanced A/H3N2 and B/Victoria IgG, and CD4+ T cell responses to all antigens, in older PWH. CONCLUSION. Our data demonstrate partial efficacy of high-dose in augmenting antibody responses of older PWH while highlighting limitations in boosting A/H1N1-specific responses. TRIAL REGISTRATION. ClinicalTrials.gov NCT04487041. FUNDING. NIH grant (5R01AG068110).
Authors
Jonah Kupritz, Sheldon Davis, TianHao Liu, Prabhsimran Singh, Daniel Andrés Díaz–Pachón, Allan Rodriguez, Scott D. Boyd, Rajendra Pahwa, Suresh Pallikkuth, Savita G. Pahwa
