Comparison of SARS-CoV-2 antibody responses following the second dose of BNT162b2 and mRNA-1273 vaccines in people living with HIV-1.

BACKGROUND

People living with human immunodeficiency virus type 1 (PLWH) are at increased risk for severe outcomes following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although SARS-CoV-2 mRNA vaccines have demonstrated strong immunogenicity in general populations, comparative data regarding the humoral immune responses in PLWH remain limited. This study aimed to compare the humoral responses elicited by two widely used mRNA vaccines, BNT162b2 and mRNA-1273, in Japanese PLWH.

METHODS

This observational study investigated 119 PLWH without prior SARS-CoV-2 infection who received two doses of BNT162b2 (n = 91) or mRNA-1273 (n = 28). Anti-SARS-CoV-2 spike antibody titers were measured at three time points: before vaccination and approximately 6 weeks and 24 weeks after the second vaccine dose. Factors associated with the antibody responses were analyzed by multivariate logistic regression.

RESULTS

Both vaccines elicited robust antibody responses in PLWH, with the mRNA-1273 group having significantly higher antibody titers than the BNT162b2 group at 6 and 24 weeks (P < 0.0001). Receipt of mRNA-1273 was independently associated with antibody titers ≥4160 AU/mL at 6 weeks (adjusted odds ratio, 24.1; 95 % confidence interval, 6.26-161) and ≥ 1000 AU/mL at 24 weeks (adjusted odds ratio, 21.7; 95 % confidence interval, 6.72-85.5). Other factors associated with higher antibody titers included younger age, higher CD4+ T cell count, and absence of smoking history. Despite the differences in the antibody levels, no severe COVID-19 infections occurred during the follow-up period.

CONCLUSIONS

BNT162b2 and mRNA-1273 both induce effective humoral responses in PLWH, with mRNA-1273 producing significantly higher and more durable antibody titers. The present findings support vaccine selection strategies tailored to immunocompromised populations and highlight the need for continued monitoring and consideration of booster doses.