Humoral SARS-CoV-2 vaccine responses are durable in solid organ transplant recipients with and without HIV

Background

Solid organ transplant (SOT) recipients may have a suboptimal humoral immune response to the coronavirus disease 2019 (COVID-19) vaccine, prompting the need for additional doses of vaccine for immunocompromised patients. However, data regarding immune responses to vaccination specifically in SOT recipients with well controlled HIV are lacking.

Methods

We conducted a prospective observational cohort single-center study of SOT recipients with and without HIV-1 who had received two doses of mRNA COVID-19 vaccine and were planning to receive additional doses. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binding and neutralizing antibody responses were measured at several time points after vaccination.

Findings

Of the 122 SOT recipients enrolled, 44 (36%) were people with HIV (PWH). Overall, 65% (50/77) of all SOT recipients were seropositive prior to a third vaccine dose. Seropositive SOT recipients with HIV had comparable anti-spike antibody responses at baseline and over time to those without HIV. In addition, HIV status did not impact neutralizing titers in our SOT cohort. Twenty-seven participants were seronegative at baseline; three (11%) were participants with HIV. In addition, 78% (21/27) of participants seroconverted over the duration of the study; of those who remained seronegative, none had HIV, but all were on an antimetabolites.

Interpretation

HIV status did not impact longitudinal spike-binding antibody titers or neutralizing titers in SOT recipients.

Research in context

Evidence before this study

Solid organ transplant (SOT) recipients may mount poor humoral immune responses to COVID-19 vaccines, prompting the need for additional vaccine doses in this patient population. Additional risk factors for poor immune response in this population have been described and include for example, age or use of certain immunosuppressant therapies. However, humoral responses to COVID-19 vaccine in SOT recipients with HIV have not previously been described.

Added value of this study

We conducted a prospective observational single center study of solid organ transplant recipients with and without HIV and measured SARS-CoV-2 binding and neutralizing antibody responses longitudinally. Our study results demonstrate that HIV status did not appear to be an additional risk factor that affected the durability of spike-antibody titers or neutralizing titers in SOT recipients over time.

Implications of all the available evidence

Well-controlled HIV infection is not an additional risk factor in SOT recipients when assessing responses to COVID-19 vaccine. Future studies should continue to focus on other risk factors, such as type of immunosuppressant therapies and timing of vaccination in relationship to transplant.