Antibody response against SARS-CoV-2 spike protein in people with HIV after COVID-19 vaccination

Background: People with HIV (PWH) often have a suboptimal response to vaccines, raising concerns about the efficacy of coronavirus disease 2019 (COVID-19) vaccines in this population. We aimed to evaluate the humoral immune response to the B.1 lineage and Omicron variant in PWH following COVID-19 vaccination. Methods: We conducted a prospective study on 19 PWH who received a two-dose series of the COVID-19 mRNA vaccine and a booster six months later. Participants without HIV infection were included as a healthy control (HC) group. The humoral response to the COVID-19 vaccine (anti-SARS-CoV-2 S IgG levels and ability to block ACE2-S interaction) against both the original B.1 lineage and the Omicron variant was measured by immunoassays. Results: The humoral response in PWH was very strong (GMFR >8) after the second dose and strong (GMFR >4) after the booster dose for both the B.1 lineage and the Omicron variant. We found similar humoral responses to the B.1 lineage and Omicron variant between PWH and HC groups after the second and booster doses (q-value >0.05). The COVID-19 vaccine generated a significantly weaker humoral response against the Omicron variant compared to the B.1 lineage in both groups (q-value <0.05). However, this response improved after the booster dose, although the inhibition of ACE2-S interaction remained weaker in PWH. Conclusions: PWH generated a strong humoral response to the COVID-19 vaccine against both the B.1 lineage and the Omicron variant, similar to individuals without HIV infection. However, our data suggest the need for booster doses to improve immunogenicity and update COVID-19 vaccines for new variants like Omicron.