AstraZeneca vaccine vials. – CHRISTOF STACHE / AFP
The pharmaceutical giant is trying to reassure. AstraZeneca’s Covid-19 vaccine is 76% effective against symptomatic cases, the Swedish-British laboratory announced Thursday, after an update of its data from a clinical trial in the United States, Peru , and Chile.
The results of the “primary analysis of phase III trials [du vaccin] in the United States have confirmed that [son] effectiveness was consistent “with the data announced Monday, AstraZeneca said in a statement. The laboratory also announced that the effectiveness of its vaccine was 100% in preventing severe cases of Covid-19, a figure similar to that previously announced.
The vaccine still not approved in the United States
AstraZeneca pledged Tuesday to provide recent data within 48 hours to the US regulator overseeing clinical trials, which had criticized potentially “obsolete” data on its anti-Covid vaccine, then announced 79% effective in preventing symptomatic cases.
Used in many countries including the European Union, the vaccine developed by AstraZeneca and the University of Oxford has not yet been approved in the United States, where the authorities had requested more data on phase III trials conducted on American territory.
“Obsolete information”
After the publication of the results of these trials on Monday, the National Institute of Infectious Diseases and Allergies (NIAID), which oversees clinical trials of vaccines in the United States, had expressed its “concern” that the Swedish laboratory British company was able to “use obsolete information” in the course of its tests. This could, according to NIAID, result in “an incomplete estimate of the effectiveness” of the vaccine.
As part of Operation Warp Speed launched in the spring of 2020 by the Trump administration to support the development of a vaccine against Covid-19, an order for 300 million doses had been placed with AstraZeneca – much more than the number initially ordered from Pfizer / BioNTech, Moderna or Johnson & Johnson (100 million each), the three vaccines currently authorized in the United States.
Several countries have suspended the use of AstraZeneca vaccine in recent weeks for fear that it could cause blood clots, sometimes fatal. Last Thursday, the European Medicines Agency (EMA) yet deemed it “safe and effective” and the use of the vaccine resumed in some countries.