March 23 (UPI) -- Federal health officials expressed concern early Tuesday over AstraZeneca's inclusion of "outdated information" in the efficacy results of its COVID-19 vaccine's late-stage U.S. trial.
In a rare statement, the National Institute of Allergy and Infectious Diseases said the information in question "may have provided an incomplete view of the efficacy data" concerning the company's two-dose vaccine regimen.
"We urge the company to work with the [Data and Safety Monitoring Board] to review the efficacy data and ensure the most accurate and up-to-date efficacy data be made public as quickly as possible," the guidance said.
The statement was issued a day after AstraZeneca publicized results of its long-awaited late-stage U.S. trial of vaccine candidate AZD1222 that showed it had a 79% efficacy against symptomatic infection and 100% efficacy against severe disease and hospitalizations.
The company said the vaccine it developed with Oxford University was tested on more than 32,000 volunteers who were given two shots four weeks apart in the United States, Chile and Peru.
The vaccine has come under scrutiny this month as more than a dozen European countries administering the drug temporarily halted its use after a handful of cases of blood clotting were reported in patients who had received the jab. An investigation by the European drug regulator last week found no correlation and most of the countries said they would restart using the drug.
AstraZeneca said Monday an independent data-monitoring board conducted a review in the late-stage U.S. trial for the blood clotting issues and found no concerns.
It added that it would apply for emergency use authorization from the Food and Drug Administration.
More than 80 countries have authorized use of the AstraZeneca vaccine, according to COVID-19 Vaccine Tracker, a website run by professors at Canada's McGill University.
The World Health Organization also authorized it for emergency use last month.