COVID-19: AstraZeneca vaccine 79% effective in US trial amid blood clot fears

The Phase III trial of AstraZeneca's COVID-19 vaccine in the United States has demonstrated an efficacy of 79% at preventing symptomatic COVID-19 and 100% against severe disease and hospitalisation. According to a press release issued by AstraZeneca, the efficacy of the vaccine is based on the US Phase III trial, which had 32,449 participants in total. It is important to note that the efficacy of the vaccine was higher, about 80%, in participants aged 65 years or older. AstraZeneca will now seek an emergency use authorisation for its vaccine from the US Food and Drug Administrator (FDA). 

“These results add to the growing body of evidence that shows this vaccine is well tolerated and highly effective against all severities of COVID-19 and across all age groups. We are confident this vaccine can play an important role in protecting millions of people worldwide against this lethal virus. We are preparing to submit these findings to the US Food and Drug Administration and for the rollout of millions of doses across America should the vaccine be granted US Emergency Use Authorization,” Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, said in a statement. 

The US Phase III trial result comes days after several countries in the European Union had temporarily suspended the use of AstraZeneca’s vaccine over reports of blood clots in recipients. The European Medicines Agency (EMA) launched an investigation into the reports of blood clots in people who had been given AstraZeneca’s COVID-19 vaccine. On March 18, EMA concluded that there was no increase in the overall risk of blood clot in recipients of AstraZeneca’s vaccine, reaffirming its safety and efficacy. 

Fourth vaccine authorisation in the US?

If the United States FDA approves AstraZeneca’s vaccine in the coming weeks, it will become the fourth COVID-19 vaccine to receive an emergency use authorization in the country. The United States has already given approval to Pfizer-BioNTech, Moderna, and Johnson & Johnson’s COVID-19 vaccine. The most recent approval came late last month, when the FDA approved J&J’s single-dose vaccine, which is being dubbed revolutionary because of its minimal storage and transportation requirements. 

(Image Credit: PTI/AP)