Qualitative assessment of anti-SARS-CoV-2 spike protein immunogenicity (QUASI) after COVID-19 vaccination in older people living with HIV.

OBJECTIVES: Effective and safe COVID-19 vaccines have been developed and have resulted in decreased incidence and severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and can decrease secondary transmission. However, there are concerns about dampened immune responses to COVID-19 vaccination among immunocompromised patients, including people living with HIV (PLWH), which may blunt the vaccine's efficacy and durability of protection. This study aimed to assess the qualitative SARS-CoV-2 vaccine immunogenicity among PLWH after vaccination. METHODS: We conducted targeted COVID-19 vaccination (all received BNT162b2 vaccine) of PLWH (aged ≥ 55 years per state guidelines) at Yale New Haven Health System and established a longitudinal survey to assess their qualitative antibody responses at 3 weeks after the first vaccination (and prior to receipt of the second dose of the COVID-19 vaccine) (visit 1) and at 2-3 weeks after the second vaccination (visit 2) but excluded patients with prior COVID-19 infection. Our goal was to assess vaccine-induced immunity in the population we studied. Qualitative immunogenicity testing was performed using Healgen COVID-19 anti-Spike IgG/IgM rapid testing. Poisson regression with robust standard errors was used to determine factors associated with a positive IgG response. RESULTS: At visit 1, 45 of 78 subjects (57.7%) tested positive for SARS-CoV-2 anti-Spike IgG after the first dose of COVID-19 vaccine. Thirty-nine subjects returned for visit 2. Of these, 38 had positive IgG (97.5%), including 20 of 21 subjects (95.2%) with an initial negative anti-Spike IgG. Our bivariate analysis suggested that participants on an antiretroviral regimen containing integrase strand transfer inhibitors [relative risk (RR) = 1.81, 95% confidence interval (CI): 0.92-3.56, p = 0.085] were more likely to seroconvert after the first dose of the COVID-19 vaccine, while those with a CD4 count < 500 cells/µL (RR = 0.59, 95% CI: 0.33-1.05, p = 0.071), and those diagnosed with cancer or another immunosuppressive condition (RR = 0.49, 95% CI: 0.18-1.28, p = 0.15) may have been less likely to seroconvert after the first dose of the COVID-19 vaccine. The direction of these associations was similar in the multivariate model, although none of these findings reached statistical significance (RRintegrase inhibitor  = 1.71, 95% CI: 0.90-3.25, p = 0.10; RRCD4 count  = 0.68, 95% CI: 0.39-1.19, p = 0.18; RRcancer or another immunosuppressive condition  = 0.50, 95% CI: 0.19-1.33, p = 0.16). With regard to immunogenicity, we were able to record very high rates of new seroconversion following the second dose of the COVID-19 vaccine. CONCLUSIONS: Our study suggests that completing a two-dose series of BNT162b2 vaccine is critical for PLWH given suboptimal seroconversion rates after the first dose and subsequent improved seroconversion rates after the second dose.