Researchers urge govts to delay Pfizer vaccine's second dose, cite data

Danuta Skowronski and Gaston De Serres said their findings were derived from Pfizer's documents submitted to the US FDA

Two Canada-based researchers on Wednesday urged governments to delay administering the second dose of Pfizer Inc's Covid-19 vaccine, which they said had an efficacy of 92.6 per cent after the first dose, as it was not significantly beneficial in the short term.

Danuta Skowronski and Gaston De Serres said their findings were derived from Pfizer's documents submitted to the US Food and Drug Administration (FDA).

These findings were also similar to the first-dose efficacy of 92.1 per cent reported for Moderna Inc's mRNA-1273 vaccine, Skowronski and De Serres said in their letter published in the New England Journal of