Oxford COVID vaccine safe, effective, Indian trials running smoothly: Serum Institute

That said, varied age groups with different dosage forms will result in slight variations and efficacy. "We must be patient and not panic," it added.

SII is conducting clinical trials of AstraZeneca-Oxford's COVID-19 vaccine candidate in India.

"The Indian trials are running smoothly with strict adherence to all the necessary processes and protocols. So far, there are no concerns. However, we are going through the data that is available and will make further statement, if needed," SII said.

Earlier this week, AstraZeneca said an interim analysis of clinical trials of its COVID-19 vaccine in the UK and Brazil showed that it was 70 percent effective on average, becoming the third drugmaker to announce promising results to contain the deadly virus.

The company had also said that the vaccine, developed with the University of Oxford, showed 90 percent efficacy in one dosing regimen when the vaccine was given as a half dose, followed by a full dose at least a month later, while another dosing regimen showed 62 percent efficacy when given as two full doses at least one month apart.

"The combined analysis from both dosing regimens resulted in an average efficacy of 70 percent," it had said.

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