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Single-dose Johnson & Johnson vaccine effective against COVID-19 variants: Data

2:25
Johnson and Johnson set to release date for vaccine authorization
Phill Magakoe/AFP via Getty Images, FILE
ByStephanie Ebbs and Sony Salzman
February 24, 2021, 3:40 PM

Johnson & Johnson and the FDA on Wednesday released respective detailed analysis on the one-shot COVID-19 vaccine, with the FDA announcing the company's data meets the requirements for the emergency use authorization review process.

FDA scientists found that the Johnson & Johnson vaccine was 85% effective at preventing severe illness in clinical trials and 66% effective at preventing COVID-19 cases with any symptoms.

Importantly, the data released shows the vaccine works against all variants. The vaccine was less effective at preventing symptomatic illness in South Africa, where the variant first detected there is dominant, but it was still highly effective at preventing severe disease there.

J&J also released preliminary data indicating the vaccine likely helps prevent asymptomatic infections, and that the Brazil variant doesn't appear to have as much of an impact on vaccine efficacy as the South African variant.

Empty vials that contained a dose of the Johnson & Johnson vaccine against the COVID-19 coronavirus at the Klerksdorp Hospital on Feb. 18, 2021.
Phill Magakoe/AFP via Getty Images, FILE

If authorized, J&J expects said they would have 4 million doses available to ship immediately, 20 million doses by March, and 100 million doses by the end of June. The Johnson & Johnson vaccine would be authorized for adults over 18.

When combined with the supply of Pfizer and Moderna vaccines, which both require two doses, the U.S. is expected to have enough vaccine for 130 million adults by the end of March.

The vaccine won't be authorized until Friday or later. First, there will be a public hearing Friday, in which the FDA's independent advisory committee will give an authorization recommendation for or against. The FDA could then make its decision as early as Friday evening.

"Although we are cautious not to prejudge the outcome of the ongoing FDA review process, we believe that our single dose vaccine will be a critical tool for fighting this global pandemic," Richard Nettles, vide president of medical affairs for Jannsen Pharmaceutical Companies testified in a congressional hearing this week.

The FDA found no serious safety concerns with mild side effects like pain at the site of injection, headache, or fatigue. About 9% of volunteers who received the vaccine had a fever.

The data released Wednesday is a more detailed version of what the company previously outlined in a press release.

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