AstraZeneca revises vaccine efficacy to 76 per cent after dispute over US study

UK-Swedish drugmaker AstraZeneca on Thursday reasserted effectiveness of its vaccine after recalculating data from the disputed US study, albeit revising its efficacy in preventing symptomatic coronavirus cases down by three percentage points to 76 per cent.

On Monday, AstraZeneca, which has yet to have its vaccine authorised in the United States, had reported 79 per cent efficacy of its drug against symptomatic COVID-19. The same day, the US' Data and Safety Monitoring Board (DSMB) expressed concern that AstraZeneca "may have included outdated information" in the efficacy data.

"Positive high-level results from the primary analysis of the Phase III trial of AZD1222 in the US have confirmed vaccine efficacy consistent with the pre-specified interim analysis announced on Monday 22 March 2021...The primary endpoint, vaccine efficacy at preventing symptomatic COVID-19 was 76 per cent," the company said in a fresh press release.

The fresh analysis included 49 more COVID-19 symptomatic cases that had turned up in the 32,449 US trial participants, pushing the figure to 190. The company also warned that "there are 14 additional possible or probable cases to be adjudicated so the total number of cases and the point estimate may fluctuate slightly."

As for severe COVID-19 cases, the vaccine was confirmed to be 100 percent effective, the pharma giant added.

AstraZeneca has already submitted the results to the DSMB, noting that it "will be the basis for a regulatory submission for Emergency Use Authorisation to the US Food and Drug Administration in the coming weeks." (/Sputnik)

( With inputs from ANI )