AstraZeneca reported Monday that its COVID-19 vaccine provided strong protection among adults of all ages in a long-anticipated US study, a finding that could help rebuild public confidence in the shot around the world and move it a step closer to clearance in the US.
In the study of 30,000 people, the vaccine was 79 per cent effective at preventing symptomatic cases of COVID-19 – including in older adults. There were no severe illnesses or hospitalisations among vaccinated volunteers, compared with five such cases in participants who received dummy shots – a small number, but consistent with findings from Britain and other countries that the vaccine protects against the worst of the disease.
AstraZeneca also said the study’s independent safety monitors found no serious side effects, including no increased risk of rare blood clots like those identified in Europe, a scare that led numerous countries to briefly suspend vaccinations last week.
“I do hope it puts to bed any doubts about the vaccine’s efficacy,” Mene Pangalos, AstraZeneca’s biopharmaceuticals research chief, told The Associated Press. “Overall, where the vaccine is being used, it’s been shown to be highly effective. So I hope that the US study now will continue to give the vaccine some momentum and get it used even further around the world.”
The company aims to file an application with the Food and Drug Administration (FDA) in the coming weeks, and the government’s outside advisers will publicly debate the evidence before the agency makes a decision. Pangalos said the vaccine could win emergency authorisation towards the second half of April. If so, the company would deliver 30 million doses immediately and an additional 20 million within the first month.
What that will mean for America’s vaccination plans is unclear. The Biden administration already projects there will be enough doses for all adults by the end of May, thanks to increasing supplies from the makers of the three vaccines already in use in the US – Pfizer, Moderna and Johnson & Johnson.
Federal officials said they didn’t want to prejudge the FDA’s review, but cast the AstraZeneca findings as a victory both for the US supply and the global fight against the virus.
“There are very many countries in Europe and throughout the world who have already authorised this, so the fact that a United States-run study has confirmed the efficacy and the safety of this vaccine, I think, is an important contribution to global health in general,” said Dr Anthony Fauci, the top US infectious disease expert.