AstraZeneca-Oxford Vaccine Protective Against COVID-19 in People With HIV

By David Douglas

July 19, 2021

NEW YORK (Reuters Health) - The AstraZeneca-Oxford COVID-19 vaccine (ChAdOx1 nCoV-19, or AZD1222) is effective in people living with HIV, at least in the short term, according to an open-label substudy within the protocol of a larger phase-2/3 trial.

As Dr. John Frater told Reuters Health by email, "This is the first comprehensive study of immune responses following vaccination against SARS-CoV-2 in people with HIV. It shows there is no significant difference in responses compared to HIV negative controls up to 8 weeks after receiving the vaccine. These data should reassure those with HIV on antiretroviral therapy that they will receive good protection against COVID-19 after vaccination, and reinforces the message that people should be coming forward to get vaccinated."

In a new paper in The Lancet HIV, Dr. Frater of the University of Oxford, in the U.K., and colleagues report that they studied 54 vaccine recipients with a median age of 42.5 years. All were men on antiretroviral therapy (ART) for HIV, with undetectable plasma HIV viral loads and CD4 counts of more than 350 cells per microliter.

The patients were given a prime-boost regimen of ChAdOx1 nCoV-19, with two doses given four to six weeks apart. All outcomes were compared with an HIV-uninfected group from the main study who were of the same age group and dosing strategy. Results were reported until day 56 after prime vaccination.

There were no serious adverse events but there were a number of local and systemic reactions during the first seven days after prime vaccination. These included pain at the injection site (49%), fatigue (47%) and headache (47%). However, the frequencies of these events were similar in the HIV-negative participants.

Antibodies against the SARS-CoV-2 spike protein peaked at day 42 after the prime dose (14 days after the boost dose) and were sustained to day 56.

Compared with HIV-negative participants, there was no difference in responses at days 14 and 28, but these were significantly higher in the HIV-positive cohort at days 42 and 56. No correlation was found between the magnitude of the anti-spike IgG response at day 56 and CD4 cell count or age.

"More data are needed on longer-term responses - which we are currently analysing - and for those with low CD4 T cell counts, but these early results are extremely encouraging for the HIV community," Dr. Frater said.

Dr. Matthew A. Spinelli of the University of California, San Francisco, who wrote an accompanying editorial, told Reuters Health by email, "At this point, with studies ongoing, it is unknown if people living with HIV (PLWH) may have diminished response to SARS-CoV-2 vaccines as has been seen in other immunocompromised populations. The possibility of a lower clinical response among PLWH in the Novavax South African sites and concerns about diminished response following natural infection raise some concerns, although data among PLWH with high CD4 counts and virologic suppression, such as (in the current study) has been reassuring."

He added, "It is possible that individuals with lower CD4 counts or longer time to start antiretrovirals may have diminished responses to SARS-CoV-2 vaccination, although additional data is needed. I am hopeful that for the highly immunogenic vaccines such as the mRNA vaccines, there will be minimal impact on clinical efficacy. The most effective SARS-CoV-2 prevention strategy among PLWH remains SARS-CoV-2 vaccination and I expect more data to be forthcoming soon."

SOURCE: and The Lancet HIV, online June 18, 2021.