AstraZeneca’s key test results for its COVID-19 vaccine in the United States, Issued by press release On Monday morning, the experts’ expectations were exceeded. But less than a day later, US health officials questioned the results, and the results have not yet been fully announced.
in a Trial The company said it involved more than 32,000 volunteers, of which about two-thirds were vaccinated, and these vaccines are 79% effective in preventing symptomatic COVID-19. This is based on 141 cases of disease that occurred in the trial vaccine and placebo groups. There are no severe cases requiring hospitalization among the vaccinated people, Compared to five in the placebo groupAnthony Fauci, head of the National Institute of Allergy and Infectious Diseases (NIAID), said at a White House press conference on Monday.
“The good news is that different races and ages are equally effective,” Fauci said.
but Early tuesday morning, NIAID issued a very unusual statement that raised some questions about the company’s performance report. The statement stated that the company “may contain outdated information about the trial” and “this may provide an incomplete view of the efficacy data.”
The statement said that late Monday, the Data Security Monitoring Board, a panel of independent medical experts overseeing AstraZeneca’s US trial, notified NIAID and other health officials that it expressed “concern” about the way the results were presented.
On Tuesday morning, AstraZeneca responded to the concerns raised by the independent expert panel. “digital Publish Yesterday was based on a pre-specified interim analysis, and the data deadline is February 17,” the company wrote. “We have reviewed the preliminary assessment of the preliminary analysis and the results are consistent with the interim analysis. We are now completing the verification of statistical analysis. “
The company promised to “work with an independent team immediately” to “share our main analysis with the latest efficacy data,” and said it would release the results within the next two days.
“As a member of the FDA Advisory Committee, I want to view all the data — all the data that has been collected. Any experience in this area. Anything related to this decision,” said Paul Offit, a vaccine expert at the Children’s Hospital of Philadelphia, who is the FDA Member of the Vaccine Advisory Committee. “Because the most important thing we consider about these vaccines is safety. Safety, safety, safety.”
Appear in Good Morning America On Tuesday, Fauci stated that DSMB had written a “quite harsh statement” to AstraZeneca, plagiarizing Fauci, saying that they believed the data in the press release “may actually be a bit misleading.”
“It’s really unfortunate,” Fauci said. “This is indeed the unforced error you said, because the fact is that this is likely to be a very good vaccine.”
Other experts expressed similar concerns about how the company presents its data.
“It’s a good vaccine, but this kind of public relations stuff makes it a bit confusing and complicated. It’s harder for the public to analyze what’s going on. We just want a concise and clear process that is easy to explain,” the University of Florida Biostatistician Natalie Dean told BuzzFeed News. “We really don’t have any details. But on the surface it doesn’t do anyone any good.”
NIAID’s statement caught many scientists by surprise.
“We are in uncharted territory. DSMB usually does not do such things,
And prohibiting federal agencies from making statements of concern
John Moore, a virologist at Weill Cornell Medical College in New York, told BuzzFeed News via email.
The statement by US health officials is just the latest in a series of problems facing AstraZeneca’s COVID-19 vaccine trial.
The results of early trials in the UK and Brazil (conducted by Oxford University, which developed the vaccine) showed that the overall efficacy is about 70%.But scientists are critical of these trials. These trials consist of a series of experimental subgroups. The age range of patients, the dose and the interval between two vaccine injections are different, making It’s hard to explain these numbers.
This also means that the Oxford team has been unable to collect enough data to answer a key question: Can the vaccine protect the elderly who are most vulnerable to COVID-19 from getting sick? This has led some countries, including Germany initially, Delayed approval of vaccine Used for older people.
According to the company’s announcement, the new trial finally has enough data to answer this question. Analysis of the results for people 65 years and older shows that the effectiveness of preventing symptomatic COVID-19 is 80%.
“These findings reconfirm the results previously observed in the AZD1222 trial in all adult populations, but it is exciting to see similar efficacy results in people over 65 for the first time,” University of Rochester School of Medicine Ann Halsey of Co-led the trial. AstraZeneca said in the company’s press release.
Crucially, the new test in the United States and several other countries is a Simpler design Compared to those managed by the Oxford team, there are only two experimental groups. Volunteers either received two doses of the vaccine four weeks apart, or two injections of normal saline as a placebo control.
Moore has been a well-known critic of the Oxford trial. He described to BuzzFeed News last week that the US trial is a “strict agreement” that should produce results that are easier to evaluate.
The company has not released any data other than the results summarized in the press release, but stated that a paper “will be submitted to a peer-reviewed journal for publication.” The results will also serve as the core content of AstraZeneca’s application to the FDA to authorize the vaccine for emergency use in the United States.
“If the vaccine is authorized for emergency use in the U.S., we are preparing to submit these findings to the U.S. Food and Drug Administration and prepare to launch millions of doses of the vaccine in the U.S.,” Mene Pangalos, executive vice president of AstraZeneca Biopharmaceuticals, said in Monday’s news. Said at the press conference. .
These results indicate that AstraZeneca’s two-dose vaccine is more effective in preventing COVID-19 than the single-dose vaccine produced by Johnson & Johnson, which is 66% effective Prevent disease in its main experiment. Neither seems to be as effective as the two-shot vaccines produced by Pfizer/BioNTech and Moderna, the latter being more than 90% effective. All four vaccines seem to provide very strong protection against severe COVID-19.
The new test results were released after the AstraZeneca vaccine safety panic last week, when many European countries temporarily stopped using the vaccine. Rare but serious reports of thrombosis.
The European Medicines Agency then analyzed the data of nearly 20 million vaccinated people and found 18 cases Cerebral Venous Sinus Thrombosis (CVST), which can prevent blood from draining from the brain and cause bleeding, and 7 cases Disseminated intravascular coagulation (DIC), it causes clots in tiny blood vessels throughout the body.Although the agency cannot rule out a link with the vaccine, it says the vaccine’s benefits in preventing COVID-19 Far greater than the risk These are serious but very rare conditions, and it is recommended to resume vaccination.
AstraZeneca stated that no cases of CVST were found in its trial. This is expected, because this is very rare, and only about 21,000 people were vaccinated in the trial.
Even before US health officials issued a statement on Tuesday, some experts were concerned that the troublesome history of vaccines might make them less attractive to the American public than existing alternatives.
“The FDA must make a decision now, but even if this vaccine is approved, it will be difficult to convince the public to accept it,” Moore told BuzzFeed News on Monday. “In this case, perception can become a reality, and public trust may not exist at all now.”
Last week, the The Biden administration announced It will loan millions of doses of AstraZeneca’s pre-made vaccine to Canada and Mexico, where the vaccine has already been approved.
Dan Vergano reported on this story.