A test tube labelled with the Vaccine is seen in front of AstraZeneca logo in this illustration taken, September 9, 2020. (Photo: REUTERS)

The increased response was seen in people who were previously vaccinated with either Vaxzevria or an mRNA vaccine, the drugmaker said, adding that it would submit this data to regulators worldwide given the urgent need for boosters.

AstraZeneca has developed the vaccine with researchers from the University of Oxford, and lab studies last month found a three-dose course of Vaxzevria was effective against the rapidly spreading new variant.

The company said the data adds to the growing evidence that supports a third dose of its vaccine irrespective of the primary vaccination schedule.