Pfizer to seek US authorisation for a third dose of its Covid-19 vaccine

Company says nother shot within 12 months could dramatically boost immunity

antibodies naturally wane over time, so studies also are under way to tell if and when boosters might be needed. Photograph:  Javier Torres/AFP via Getty

antibodies naturally wane over time, so studies also are under way to tell if and when boosters might be needed. Photograph: Javier Torres/AFP via Getty

 

Pfizer is to seek US authorisation for a third dose of its Covid-19 vaccine, saying that another shot within 12 months could dramatically boost immunity and maybe help ward off the latest variant.

Research from multiple countries shows the Pfizer shot and other widely used vaccines offer strong protection against the highly contagious Delta variant, which is spreading rapidly around the world and now accounts for most new US infections.

Two doses of most vaccines are critical to develop high levels of virus-fighting antibodies against all versions of the coronavirus, not just the Delta variant – and most of the world still is desperate to get those initial protective doses as the pandemic continues to rage.

Total doses distributed to Ireland Total doses administered in Ireland
8,557,330 7,130,149

But antibodies naturally wane over time, so studies also are under way to tell if and when boosters might be needed.

On Thursday, Pfizer’s Dr Mikael Dolsten told The Associated Press that early data from the company’s booster study suggests people’s antibody levels jump five to 10-fold after a third dose, compared to their second dose months earlier.

In August, Pfizer plans to ask the Food and Drug Administration for emergency authorisation of a third dose, he said.

Currently only about 48 per cent of the US population is fully vaccinated – and some parts of the country have far lower immunisation rates, places where the Delta variant is surging. – AP