Immunogenicity of SARS-CoV-2 infection and Ad26.CoV2.S vaccination in people living with HIV

Summary Background People living with HIV (PLWH) have been reported to have an increased risk of more severe COVID-19 disease outcome and an increased risk of death relative to HIV-uninfected individuals. Here we assessed the ability of the Johnson and Johnson Ad26.CoV2.S vaccine to elicit neutralizing antibodies to the Delta variant in PLWH relative to HIV-uninfected individuals. We also compared the neutralization after vaccination to neutralization elicited by SARS-CoV-2 infection only in HIV-uninfected, suppressed HIV PLWH, and PLWH with detectable HIV viremia. Methods We enrolled 26 PLWH and 73 HIV-uninfected participants from the SISONKE phase 3b open label South African clinical trial of the Ad26.CoV2.S vaccine in health care workers (HCW). Enrollment was a median 56 days (range 19-98 days) post-vaccination and PLWH in this group had well controlled HIV infection. We also enrolled unvaccinated participants previously infected with SARS-CoV-2. This group consisted of 34 PLWH and 28 HIV-uninfected individuals. 10 of the 34 (29%) SARS-CoV-2 infected only PLWH had detectable HIV viremia. We used records of a positive SARS-CoV-2 qPCR result, or when a positive result was absent, testing for SARS-CoV-2 nucleocapsid antibodies, to determine which vaccinated participants were SARS-CoV-2 infected prior to vaccination. Neutralization capacity was assessed using participant plasma in a live virus neutralization assay of the Delta SARS-CoV-2 variant currently dominating infections in South Africa. This study was approved by the Biomedical Research Ethics Committee at the University of KwaZulu–Natal (reference BREC/00001275/2020). Findings The majority (68%) of Ad26.CoV2.S vaccinated HCW were found to be previously infected with SARS-CoV-2. In this group, Delta variant neutralization was 9-fold higher compared to the infected only group (GMT=306 versus 36, p Interpretation The neutralization response of the Delta variant following Ad26.CoV2.S vaccination in PLWH with well controlled HIV was not inferior to HIV-uninfected study participants. In SARS-CoV-2 infected and non-vaccinated participants, the presence of HIV infection reduced the neutralization response to SARS-CoV-2 infection, and this effect was strongest in PLWH with detectable HIV viremia Funding South African Medical Research Council, The Bill & Melinda Gates Foundation.