This plain language summary from Future Virology presents the results of two global clinical studies of the Janssen Ad26.COV2.S vaccine against COVID-19. ENSEMBLE study looked at the effectiveness of a single injection of the vaccine. ENSEMBLE2 study looked at the effectiveness of a booster dose of the vaccine given 2 months after the first dose. 

Read the summary here.

The original articles on which this summary is based are:

‘Final analysis of efficacy and safety of single-dose Ad26.COV2.S’ published in the New England Journal of Medicine in 2022. This article is available for free here.

‘Efficacy, safety, and immunogenicity of a booster regimen of Ad26.COV2.S vaccine against COVID-19 (ENSEMBLE2): results of a randomised, double-blind, placebo-controlled, phase 3 trial’ published in The Lancet Infectious Diseases in 2022. This article is available for free here.