Federal regulators on March 23 said they were “concerned” that drug maker AstraZeneca included “outdated information” in its announcement the previous day that the company’s COVID-19 vaccine was effective.
The federal Data and Safety Monitoring Board shared those concerns with the company as well as with the National Institute of Allergy and Infectious Diseases, and the U.S. Biomedical Advanced Research and Development Authority, according to a statement from NIAID issued early March 23.
“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 agency said.
The NIAID statement does not say what data may have been outdated or how it may have changed the results. The company said March 22 it plans to see U.S. authorization for the vaccine in April.
The statement from NIAID comes a day after AstraZeneca said the interim results of their phase III U.S. study found it was 79% effective against symptomatic COVID-19, 80% effective in people 65 years and older, and 100% effective against severe or critical disease and hospitalization.
Company officials and clinical trial investigators on March 22 also addressed the recent concerns about blood clots, how well the vaccine will perform against variants, and provided a timeline for seeking regulatory approval.
“There are many countries in Europe and throughout the world that have already authorized this. The fact that a United States-run study has confirmed the efficacy and safety of this vaccine, I think is an important contribution to global health in general,” Anthony Fauci, MD, chief medical advisor to President Joe Biden, said during a White House press briefing March 22.
Andy Slavitt, White House senior advisor for the COVID-19 Response Team, had a more tempered reaction.
“It’s important to remind everyone we cannot and will not get ahead of the FDA,” he said. “While we would certainly call today’s news encouraging, it’s the kind of thing we like to see, we have a rigorous process that will come once an EUA is submitted and that will give us more information.”
With 30 million doses at the ready, the company plans to file for FDA emergency use authorization “within weeks,” Menelas Pangalos, executive vice president of biopharmaceuticals research and development at AstraZeneca, said during a media briefing March 22.
Risk of thrombosis addressed
Regarding highly publicized reports of problems with blood clots from the AstraZeneca vaccine, the World Health Organization found the vaccine creates no greater risks, as did the European Medicines Agency
“We’ve had absolute confidence in the efficacy of the vaccine. Seeing this data now I hope gives others increased confidence that this is a very safe and effective vaccine,” Mr. Pangalos said.
“We’re glad this is being investigated really thoroughly,” Magda Sobieszczyk, MD, an infectious disease specialist at Columbia University In New York City, said. “It’s incredibly reassuring that the regulatory agencies have looked at the data thoroughly and there is no enhanced signal above what is seen in the population.”
“There were no concerning signals noted in the U.S. data,” she added.
Regarding the risk of blood clots, “These data are therefore timely in further addressing any safety concerns that could undermine vaccine uptake.” Andrew Garrett, PhD, executive vice president of scientific operations at ICON Clinical Research, agreed.
The vaccine was well-tolerated, the company reported, with no serious adverse events. Temporary pain and tenderness at the injection site, mild-to-moderate headaches, fatigue, chills, fever, muscle aches. and malaise were among the reported reactions.
The phase III interim results show 141 cases of symptomatic COVID-19 in the study of 32,449 adults. “We don’t have the whole breakdown yet . . . these are the high-level results we just got this week,” Mr. Pangalos said. Further information on rates of mild to moderate COVID-19 illness between groups is not yet available, for example.
The company explained that participants were randomly assigned to vaccine or placebo, with twice as many receiving the actual vaccine.
The trial is ongoing, so the FDA will receive information on more than the 141 COVID-19 symptomatic cases when the company submits a full primary analysis to the agency, Mr. Pangalos said.
In the phase III study, patients received two doses 4 weeks apart.
Beyond the U.S. study, the company has additional information, including real-world data from the United Kingdom, that it intends to submit to the FDA. Part of this evidence suggests increased efficacy when a second dose is administered at 3 months