Antibody response to the third dose of inactivated COVID-19 vaccine in people living with HIV (PLWH): A longitudinal cohort

The immunogenicity induced by the third dose of inactivated coronavirus disease 2019 (COVID-19) vaccines in people living with HIV (PLWH) is unclear, and relevant literature is extremely scarce. It is important to add evidence on the humoral immune response induced by the third dose of inactivated COVID-19 vaccine in PLWH. We collected peripheral venous blood for spike receptor binding domain-protein specific immunoglobulin G (S-RBD-IgG) antibody tests at 28 days after the second dose (T₁ ), 180 days after the second dose (T₂ ) and 35 days after the third dose (T₃ ) of inactivated COVID-19 vaccines in PLWH. The differences in S-RBD-IgG antibody levels and specific seroprevalence among T₁ , T₂ , and T₃ time periods were analyzed, and the effects of age, vaccine brand, and CD4⁺ T cell count on the levels and specific seroprevalence of S-RBD-IgG antibody induced by the third dose in PLWH were examined. The third dose of inactivated COVID-19 vaccines induced strong S-RBD-IgG antibody responses in PLWH. The levels and specific seroprevalence of S-RBD-IgG antibody were significantly higher than those at 28 and 180 days after the second dose and were not affected by vaccine brand or CD4⁺ T cell count. Younger PLWH produced higher levels of S-RBD-IgG antibody. The third dose of inactivated COVID-19 vaccine showed good immunogenicity in PLWH. It is necessary to popularize the third dose in the PLWH population, especially PLWH who do not respond to two doses of inactivated COVID-19 vaccines. Meanwhile, the durability of the protection provided by the third dose in PLWH must be continuously monitored.

IgG Antibody Responses and Immune Persistence of Two Doses of BBIBP-CorV Vaccine or CoronaVac Vaccine in People Living with HIV (PLWH) in Shenzhen, China

The purpose of this study was to preliminarily evaluate the immunogenicity and immune persistence of inactivated SARS-CoV-2 vaccines in PLWH in the real world. We collected blood samples from 132 PLWH aged 18−59 years who were vaccinated with two doses of BBIBP-CorV vaccine (Sinopharm) or CoronaVac vaccine (SinoVac) at 28 ± 7 days and 180 ± 20 days the after second dose, to detect the level of Spike receptor binding domain-protein specific IgG (S-RBD-IgG) by using chemiluminescence. We found that the BBIBP-CorV vaccine or the CoronaVac vaccine induced lower S-RBD-IgG antibody seropositivity rates and levels in PLWH than in healthy controls (HCs). The BBIBP-CorV vaccine or the CoronaVac vaccine induced lower humoral immune responses in PLWH, having lower CD4+T cell counts (<350 cells/μL) compared to PLWH, and having higher CD4+T cell counts (≥350 cells/μL) after a second dose of vaccination. The BBIBP-CorV vaccine or the CoronaVac vaccine induced lower S-RBD-IgG antibody levels in PLWH, having CD4+T cell counts ≥350 cells/μL compared to HCs. No negative effects were observed in terms of the CD4+T cell counts and HIV RNA viral load (VL) of PLWH after vaccination. Ninety-nine PLWH and eighty-three HCs completed a second blood collection for testing; we found a statistically significant decrease in the humoral immune response both in PLWH and HCs from 28 days to 180 days after a second dose of BBIBP-CorV vaccine or CoronaVac vaccine. The S-RBD-IgG antibody induced by the BBIBP-CorV vaccine or the CoronaVac vaccine declined faster in the PLWH population than in the healthy population, and two doses of the BBIBP-CorV vaccine or the CoronaVac vaccine may not be enough to provide PLWH with persistent immunity against SARS-CoV-2. It is necessary for PLWH to be prioritized for a third dose over the healthy population, but the immunogenicity of the third dose of the homologous or heterologous vaccine requires further study.