The following is a summary of “Coronavirus disease 2019 vaccine efficacy in participants with weakened immune systems from 4 randomized-controlled trials,” published in the April 2024 issue of Infectious Diseases by Sherman et al.

Data on COVID-19 vaccine efficacy (VE) in people with mildly immuno-compromising conditions are limited despite vaccines’ success in preventing severe disease in the general population.

Researchers conducted a retrospective study analyzing the efficacy of the COVID-19 vaccine in people with mildly immuno-compromising conditions.

They used post-hoc analysis of four COVID-19 vaccine trials (Moderna, AstraZeneca Janssen, and Novavax). A tempered immune system (TIS) variable was defined based on medical history and medications to determine VE against symptomatic and severe cases of COVID-19 in TIS vs. non-TIS starting 14 days after completion of the primary series. The same model was used to analyze the participants living with controlled human immunodeficiency.

The results showed only 3,852/30,351 (12.7%) Moderna participants, 3,088/29,868 (10.3%) Novavax participants, 3,549/32,380 (11.0%) AstraZeneca participants and 5,047/43,788 (11.5%) Janssen participants had a TIS. Metabolism and nutritional disorders were the main cofactors in most TIS conditions (73.9%). All participants showed a significantly reduced likelihood of symptomatic and severe COVID-19 with vaccination vs. placebo. The VE did not differ significantly between participants with TIS and NTIS or those with HIV for symptomatic or severe COVID-19 across all trials.

Investigators concluded that mild immunity issues showed no difference in VE against COVID-19 symptoms or severity compared to those without in four vaccine trials. 

Source: academic.oup.com/cid/advance-article-abstract/doi/10.1093/cid/ciae192/7643769