On the evening of March 24, AstraZeneca announced Its Covid-19 vaccine is 76 percent effective in preventing symptomatic disease, based on Phase III trials of more than 32,000 participants, mostly in the United States. The results summed up a whirlwind of news about the AstraZeneca vaccine in March.
Currently, the vaccine has been approved for use in the UK and several European Union countries since December. It has not been approved in the US because the Food and Drug Administration (FDA) asked the company to provide results from a large-scale trial, Umair Irfan reported for Sound. Experts expect data to show the vaccine is safe and effective, but are concerned about how AstraZeneca’s recent hurdles could affect its reputation around the world.
“I think the way the ship will be repaired is with FDA supervision,” biostatistician Stephen Evans of the London School of Hygiene & Tropical Medicine told Smriti Mallapaty and Ewen Callaway at Natural. Evans hopes the vaccine will be approved when the FDA can review the raw data.
On March 18, the European Medicines Agency (EMA) completed its review of the AstraZeneca vaccine created in partnership with the University of Oxford, and concluded that it was safe and effective, BBC news report. The EU’s medical regulatory agency has reviewed the safety of the vaccine because, of the roughly 17 million people who got the injection in early March, 37 had unusual blood clots.
More than 20 countries are suspending vaccine use while EMA is reviewing cases, Kai Kupferschmidt and Gretchen Vogel report on Science magazine. Most countries resumed vaccine use after the EMA concluded it was safe, but last week Norway extended the vaccine suspension to April 15, Gwladys Fouche and Terje Solsvik reported to Reuters. Norwegian officials hope more data on the causes of blood clots will be available soon.
On March 22, AstraZeneca released its preliminary results from its Phase III trial, which show slightly higher effectiveness in preventing Covid-19 than the latest results. The results have been long awaited. The FDA asked companies to conduct larger trials to get clearer data than they collected in their first round of testing. In the UK’s first trial, some participants unexpectedly received half the dose from the first injection of the vaccine, and the initial trial did not involve enough people over 65 years of age, reports. Washington Post.
On the morning of March 23, officials at the National Institute of Allergy and Infectious Diseases released a letter from the data and security monitoring board that had examined AstraZeneca’s trial, Andrew Joseph reported for STAT News. The letter stated that AstraZeneca had used old data to achieve its effectiveness figures. That move was unprecedented; Usually, the supervisory board keeps their correspondence with the company secret.
“We just feel we can’t stay still. Because if we stay silent, it’s understandable that we are accused of covering up something. And we definitely don’t want to be in that position, “Anthony Fauci, director of NIAID, told STAT News. “In my mind, this is the company’s own fault.”
AstraZeneca describes preliminary results including data collected up to February 17 as per Natural.
Within 48 hours, AstraZeneca released the revised results with updated data. According to statement, the vaccine has 76 percent effectiveness in reducing symptoms of Covid-19 overall, and 85 percent efficacy in people aged 65 and over. A special review of 32,000 participants in the US trial found no cases of unusual blood clots causing doubt in Europe, per STAT News.
“The benefits of this result will primarily benefit the rest of the world, where confidence in the AstraZeneca vaccine has been eroded,” Evans told New York Time.
AstraZeneca plans to submit data for emergency use authorization in the coming weeks and then the FDA will have additional time to review the data and make its decision.
The AstraZeneca vaccine may not have a big role in vaccinating people in the United States because the three companies that have agreed to supply the vaccine in the country agreed to provide sufficient doses to anyone who wants it this year. But AstraZeneca participates in the COVAX program to deliver doses to low- and middle-income countries without benefit, and FDA approval is the global gold standard for the safety of treatment.
“Ultimately, the FDA looks at data, not press releases,” former FDA chief scientist Jesse Goodman told Sound. “Looking at that data and doing their own analysis is what will determine whether this vaccine gets [emergency use authorization], whether the benefits outweigh the risks. “