AstraZeneca released updated information on its COVID-19 clinical trial on Wednesday evening. shows an effectiveness rate of 76% instead of the 79% rate it claimed earlier in the week.
On Monday, the company that developed its vaccine in collaboration with scientists from Oxford University, published interim data From a 32,000-person trial conducted in the United States, Chile, and Peru this winter.
But an independent review board These examined the results and said the data was misleading as it only contained information until February 17.
As of February 17, 141 people in the study had received COVID-19, the vast majority in the group that received a saltwater placebo instead of the active vaccine. Among these people, the vaccine was 79% effective in preventing symptoms of COVID-19 and 100% effective in preventing serious illness and hospitalization.
The updated information, which included 190 symptomatic cases, showed only a slightly different picture.
The vaccine prevented 76% of symptomatic illnesses two weeks after the second dose, as well as all serious illness and hospital stays, according to the updated data. According to the new data, it was 85% effective against symptomatic COVID-19 in subjects 65 and older instead of the 80% previously reported.
Eight study participants developed severe COVID-19, all of whom received a salt shot instead of an active vaccine, the company said.
Fourteen more cases of possible or likely infection have yet to be fully investigated, so the numbers may change slightly, the company said.
The AstraZeneca-Oxford vaccine is not yet available in the US. However, employees are expected to use their trial data to apply for approval from the Food and Drug Administration within a few weeks.
The updated numbers show that the vaccine continues to be effective enough to meet the FDA’s standards of effectiveness.
The study also showed that the vaccine is very safe, despite concerns expressed in Europe about a dozen or so rare blood clot cases among the 20 million people vaccinated there. European and UK drug regulators and the World Health Organization have classified the AstraZeneca-Oxford vaccine as safe, but couldn’t completely rule out that the shot played a role in the unusual blood clots.
Regulators will continue to track vaccine recipients to make sure the blood clots are not a problem. None were seen in the US trial.
It’s not clear why AstraZeneca presented dated information to the public as it knew the remaining numbers would have to be a few weeks later, especially because the results were so similar.
Dr. Anthony Fauci, the country’s foremost infectious disease doctor, was asked in a press conference at the White House on Wednesday why the company released the earlier numbers.
He said AstraZeneca-Oxford disagreed with the independent review body, officially known as the Data and Security Oversight Board, on what figures should be released. The National Institutes of Health issued a press release in which the company figures are copied.
“On that basis, since we ourselves – that is, the federal government in the form of the NIH – had published a press release that reflected almost exactly what AZ had done, we published a very brief press release that We urge AZ to contact itself Reaching out to the Data and Safety Monitoring Board again to make sure the data published accurately reflects the actual data, so that’s the whole story, “Fauci said.
At the same press conference, Andy Slavitt, White House senior advisor on COVID response, said the agency was merely trying to be transparent in order to increase public confidence. The Food and Drug Administration’s approval process, which all vaccines must go through, remains very strict, he said.
“So I urge us not to focus on the process of the last few days,” concluded Slavitt, “but rather to focus on the essentials of what happens when these applications for these candidates are submitted to the FDA.”
Contact Karen Weintraub at [email protected]
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