ChAdOx1 nCoV-19 Vaccine Safe and Immunogenic in Individuals With HIV

Close-up of a doctor applying the covid-19 vaccine to a senior patient at nursing home during the isolation. Healthcare and medicine concept.
A team of investigators sought to characterize immune responses to vaccination against SARS-CoV-2 in people with HIV.

The ChAdOx1 nCoV-19 vaccine against SARS-CoV-2 was found to be safe and immunogenic in a study of patients diagnosed with HIV published in The Lancet HIV.

Patients aged 18 to 55 years with HIV were enrolled from 2 HIV clinics in London for this single-arm, open-label, vaccination substudy. All participants were required to be on antiviral therapy and have undetectable plasma HIV viral loads of <50 copies per mL as well as CD4 counts of >350 cells per μL. Participants received 2 doses of the vaccine 4 to 6 weeks apart.

A total of 54 participants, all men, completed the vaccine schedule, and no serious adverse events were reported. Self-reported adverse events included mild or moderate pain at the injection site, headache, and fatigue. Less commonly reported adverse events included chills, joint pain, malaise, muscle ache, feverishness, and nausea. There were no differences in frequencies of adverse events in participants with HIV compared with HIV-negative participants.

At day 42 after the prime dose and day 14 after the second dose, anti-spike protein IgG antibodies peaked (median 1440 EUs, interquartile range [IQR] 704–2728; n=50). Anti-spike antibodies were sustained to day 56 (median 941 EUs, IQR 531–1445; n=49). There were no differences in response at day 14 and 28 between patients with or without HIV; however, at days 42 and 56, patients with HIV had significantly higher responses. At day 56 there were no detectable correlations between CD4 counts (P =.93) or age (P =.48) and the magnitude of antibody response.

IFN-γ ELISpot responses peaked at day 14 after the first dose (median 674 spot-forming cells [SFCs] per million peripheral blood mononuclear cells [PBMCs], IQR 341–1223; n=44) and were sustained to day 56 (median 333 SFCs per million PBMCs, IQR 191–564; n=39). Similar results were observed for T-cell proliferation response, and there were no differences in magnitude or persistence of SARS-CoV-2 spike-specific humoral or cellular responses (P >.05 for all analyses) between patients with or without HIV.

Several study limitations of note include that these are preliminary data with results to day 56 only, this was an open-label study without randomization, and the cohort consisted primarily of White European men with high CD4 cell counts and access to long-term antiretroviral therapy.

According to the researchers, “Further studies are needed in people with HIV and other groups whose immune responses to vaccination might be suboptimal.” The researchers add that the findings “are encouraging, and reinforce the message that people living with HIV should be supported to receive vaccination.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies and the research was supported by AstraZeneca. Please see the original reference for a full list of authors’ disclosures. 


Frater J, Ewer KJ, Ogbe A, et al; for the Oxford COVID Vaccine Trial Group. Safety and immunogenicity of the ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 in HIV infection: a single-arm substudy of a phase 2/3 clinical trial. Lancet HIV. Published online June 18, 2021. doi:10.1016/S2352-3018(21)00103-X