The single-shot Johnson & Johnson vaccine is highly effective in preventing severe Covid-19, including newer variants, according to documents released by the US Food and Drug Administration.
The news came as the regulator was set to convene an independent panel Friday that will likely vote to authorise the vaccine, making it the third available in the country hit hardest by the coronavirus pandemic.
In large clinical trials, the J&J vaccine's efficacy against severe disease was 85.9% in the United States, 81.7% in South Africa, and 87.6% in Brazil.
Overall, among 39,321 participants across all regions, the efficacy against severe Covid-19 was 85.4%, but it fell to 66.1% when including moderate forms of the disease.