Pfizer, Moderna COVID vaccines got nod before Delta-dominant 2nd wave peak: Krishna Ella

"I am telling you honestly. If Pfizer and Moderna (would) have done a phase-three clinical trial during the second wave, they would not have got the license for the product," Ella said at an event organised by the Technology Development Board (TDB), a body under the Department of Science and Technology.

"When they (Pfizer and Moderna) licensed it, there was (dominance of the) Wuhan strain. So they succeeded in getting 90 per cent efficacy but now the same vaccine is showing a 35 per cent efficacy in Israel," he said.

The Delta variant is known to be more virulent than the earlier strains of SARS-CoV2.

"…and Covaxin is the only one vaccine...there was a delay in the regulatory process and we got stuck in the second wave. And (we were) lucky that in the second wave, we almost got 77 per cent efficacy. But had it been the Wuhan strain and not Delta we would have got 85 per cent efficacy," Ella added.

Covaxin is one of the three vaccines that is being administered in the country.

The drug regulator in the country has given Emergency Use Authorisation (EUA) to Moderna and Johnson and Johnson.