American federal health officials said early Tuesday that results from a U.S. trial of AstraZeneca’s COVID-19 vaccine may have included “outdated information” and that could mean the company provided an incomplete view of efficacy data.
AstraZeneca said in a statement that the data it released Monday included cases up to Feb. 17, as the study rules specified, and that it was continuing to analyse cases that have occurred since then. The company said that a preliminary analysis of data that has continued to roll in was consistent with what it had already reported.
It promised an update within 48 hours. AstraZeneca reported Monday that its COVID-19 vaccine provided strong protection among adults of all ages in a long-anticipated U.S. study, a finding that some experts hoped would help rebuild public confidence in the shot around the world and move it a step closer to clearance in the U.S.
The company in the study of more than 30,000 people reported that the vaccine was found to be 79 per cent effective at preventing symptomatic cases of COVID-19 — including in older adults. There were no severe illnesses or hospitalizations among vaccinated volunteers, compared with five such cases in participants who received dummy shots — a small number, but consistent with findings from Britain and other countries that the vaccine protects against the worst of the disease.
The study’s independent safety monitors found no serious side effects, including no increased risk of rare blood clots like those identified in Europe said AstraZeneca.
But just hours after those encouraging results were reported an unusual statement was issued by the U.S. National Institute of Allergy and Infectious Diseases.
The Data and Safety Monitoring Board “expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data, said the agency.
“We urge the company to work with the DSMB to review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible,” the statement added.
In previous vaccine trials, as is the situation here, cases have continued to accrue, even as companies began to release their data. But the AstraZeneca circumstance is unusual in drawing the concern of the data monitoring board.
Authorisation and guidelines for use of the vaccine in the United States will be determined by the FDA and Centers for Disease Control and Prevention after thorough review of the data by independent advisory committees.
The company has said it aims to file an application with the Food and Drug Administration in the coming weeks, and the government’s outside advisers will then publicly debate the evidence.
