How effective is a third dose of COVID-19 mRNA vaccine for people living with HIV?
A recent study published in Nature Communications1 investigated the safety and immunogenicity of a third dose of COVID-19 mRNA vaccine (either Pfizer-BioNTech or Moderna) in people living with HIV (PLWH) who have advanced disease (low CD4 count and/or previous AIDS diagnosis).
The study enrolled 216 PLWH who were on antiretroviral therapy (ART) and had received two doses of a COVID-19 mRNA vaccine at least 12 weeks before. The participants received a third dose of the same or a different mRNA vaccine after a median of 142 days from the second dose. The researchers measured the antibody and cellular responses to the vaccine before and after the third dose, as well as any side effects.
The results showed that the third dose was safe and well tolerated, with mild side effects reported by 68% of the participants. The third dose also induced a strong and higher antibody response than the second dose, especially when a heterologous combination with Moderna as the third shot was used. However, the cellular response remained stable after the third dose.
The researchers concluded that a third dose of COVID-19 mRNA vaccine is useful for PLWH who have severe immune dysregulation and are on suppressive ART. They suggested that a heterologous combination with Moderna as the third shot may offer better protection against variants of concern, such as Omicron, but further studies are needed to confirm this.
1: Vergori A, Cozzi Lepri A, Cicalini S, et al. Immunogenicity to COVID-19 mRNA vaccine third dose in people living with HIV. Nat Commun. 2022;13(1):4922. doi:10.1038/s41467-022-32263-7