Pfizer vaccine, researchers seek postponement of second dose

The vaccine had an efficiency of 92.6% after taking the first dose, said Danuta Skowronski and Gasston De Serres, based on an analysis of documents presented by drug producer to the American Food and Bars Administration.

Experts say these findings were similar to the efficiency the first dose of the Moderna vaccine of 92.1%.

In his response, the Pfizer company said alternative regimes on the amount of vaccine doses were not yet assessed and that the decision was due to health authorities.

Some countries, facing small amounts of vaccines, are looking at opportunities to change the amount of doses.

But such strategies are seen differently by different experts. Some argue that the emergency presented by the pandemic requires flexibility, while others oppose abandoning clinically tested approaches.

Researchers Skowronski and De Serres warned that it is not safe how long the defence lasts after taking a single dose, but said management of the second dose a month after the first provides little “benefits in the short term”.

Skowronski works for the British Columbia Disease Control Center, while De Serrez at the Kekbek National Institute of Public Health.

In Britain, authorities have said the data supports its decision to switch to a 12-week cycle of doses to doses for Pfizer vaccine. But both Pfizer and her partner BioNTech have warned they have no evidence to support that decision.

Pfizer's vaccine has been authorised to deal with a 21-day margin from dose to dose.

The FDA and the European drug agency suggest the testing interval.