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Photo: WPA Pool / Getty Images

AstraZeneca said Wednesday that a primary analysis of its Phase 3 trial data confirmed its coronavirus vaccine's "safety" with a 76% efficacy rate against symptomatic COVID.

Flashback: The company reported on Monday that a U.S. trial found its vaccine 79% effective, but faced backlash after NIAID said Tuesday it may have included information that provided an "incomplete view of the efficacy data" in its U.S. results.

Our thought bubble, via Axios' Caitlin Owens: A 3 percentage point difference in efficacy isn't much, but the public relations damage to the vaccine brought on by the last few days may be hard to undo.

By the numbers: Updated results include data from 190 symptomatic cases, 50 more than the cases studied in the dataset released Monday.

The new analysis also found:

  • 100% efficacy against severe or critical disease and hospitalization.
  • 85% efficacy against symptomatic COVID-19 in participants ages 65 years and up, a jump from a previously reported 80%.

What to watch: The Food and Drug Administration must go over the data AstraZeneca submits.

The big picture: AstraZeneca already faced controversy after more than a dozen countries suspended use of its vaccine in mid-March due to reports of blood clots in some people who had gotten the shot.

  • A European Union agency later said there is "no indication" the vaccine causes blood clots.

Go deeper

Updated Mar 23, 2021 - Health

NIAID: AstraZeneca "may have included outdated information" on COVID vaccine

A healthcare worker holds a vial of AstraZeneca's COVID-19 vaccine at the Pentland Medical Practice in Currie, Scotland, in January. Photo: Russell Cheyne - WPA Pool/Getty Images

NIAID said early Tuesday it's "concerned" that AstraZeneca "may have included outdated information" from a trial of its COVID-19 vaccine that "may have provided an incomplete view of the efficacy data."

Why it matters: The statement comes after the company announced the vaccine it developed with the University of Oxford was found to be 79% effective at preventing symptomatic COVID-19 and 100% effective against severe disease and hospitalization in a Phase III trial.

Mar 24, 2021 - Health

Why the credibility of AstraZeneca's vaccine data matters

Illustration: Aïda Amer/Axios

The world desperately needs to be able to believe in AstraZeneca’s coronavirus vaccine, and the never-ending confusion over its clinical data isn’t helping.

The big picture: The extraordinary public dispute between the company and independent experts risks undermining patients' trust, experts said, even if the vaccine turns out to work well.