Johnson & Johnson’s one-dose COVID-19 vaccine appeared safe and effective in trials, the U.S. Food and Drug Administration said Wednesday, paving the way for its approval for emergency use as soon as this week.

Axar.az reports that the vaccine was 66% effective at preventing moderate to severe COVID-19 in a 44,000 person global trial, the FDA said in documents ahead of a Friday meeting of independent experts who will advise the agency on the emergency authorization.

New data provided by J&J to the FDA showed the vaccine was 64% effective at stopping moderate to severe cases of COVID-19 after 28 days in thousands of trial participants in South Africa where a worrying new variant has swept across the country.

Overall, the vaccine was 100% effective at stopping hospitalization 28 days after vaccination, compared with 85% at 14 days, and there were no COVID-19 deaths among those who received the shot rather than a placebo.