Pfizer to seek go-ahead for third Covid-19 vaccine dose

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.

Pfizer is to seek 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.

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.

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

In a joint statement, Pfizer and BioNTech said they have seen “encouraging data in the ongoing booster trial of a third dose of the current BNT162b2 vaccine”.

The companies believe a third does “has the potential to preserve the highest levels of protective efficacy against all currently tested variants including Delta.” 

The statement added that the companies are “remaining vigilant and are developing an updated version of the Pfizer-BioNTech Covid-19 vaccine that targets the full spike protein of the Delta variant.” 

The companies said they expect to publish “more definitive data” soon, as well as in a “peer-reviewed journal and plan to submit the data to the FDA [the US Food and Drug Administration], EMA [European Medicines Agency] and other regulatory authorities in the coming weeks”.

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 Ireland, concerns around the Delta variant forced a delay to the reopening of indoor dining until at least July 19.

A further 534 cases of Covid-19 were confirmed here last night.