Johnson & Johnson Reports 85% Efficacy of Ad26.COV2.S Booster Against Omicron-Driven Hospitalizations in South Africa

Today, Johnson & Johnson announced that the latest data from a Phase 3b clinical trial showed that a homologous booster shot of the investigational single-dose COVID-19 vaccine (Ad26.COV2.S) achieved 85% vaccine efficacy in preventing COVID-19-related hospitalizations. The trial results indicated that in South Africa, where Omicron has become the dominant variant in the pandemic spread, the vaccine booster successfully reduced the risk of healthcare workers being hospitalized due to SARS-CoV-2 infections.

Ad26.COV2.S, developed by Johnson & Johnson, is a COVID-19 vaccine that uses an adenovirus serotype 26 (Ad26) vector to express the SARS-CoV-2 spike protein.

The latest data from this Phase 3 clinical trial (n=227,310) indicate that when participants receive a booster dose 6-9 months after completing the two-dose primary series, vaccine effectiveness increases over time from 63% (95% CI, 31-81%) during days 0-13 to 84% (95% CI, 67-92%) during days 14-27 post-booster, and further to 85% (95% CI, 54-95%) at 1-2 months.

Previous studies found that the Omicron variant was associated with immune escape after prior infection. In other words, even if someone had been previously infected with the coronavirus, the resulting immunity might not be sufficient to fully resist the newly emerged Omicron variant. Researchers pointed out that the increase in CD8-positive T cells induced by booster shots could be key to achieving high levels of effectiveness in preventing severe COVID-19 infections and hospitalizations.

References:

[1] Johnson & Johnson COVID-19 Vaccine Demonstrates 85 Percent Effectiveness against Hospitalization in South Africa when Omicron was Dominant. Retrieved December 30, 2021, from https://www.jnj.com/johnson-johnson-covid-19-vaccine-demonstrates-85-percent-effectiveness-against-hospitalization-in-south-africa-when-omicron-was-dominant

(Original text has been abridged)

▽Follow 【WuXi AppTecGermany】WeChat Official Account