Britain will expand access to Pfizer's oral antiviral Covid-19 treatment to thousands more people by adding it to a trial to assess how best to use the drug in its highly vaccinated population, the health ministry has said, according to Reuters.

Paxlovid, a combination of Pfizer's new pill with an older antiviral ritonavir, was made available to thousands of people with compromised immune systems in Britain in February.

Now Paxlovid is being added to the Panoramic national study in England, which is making antivirals available to a wide number of patients while collecting data on how the drugs should best be used in a vaccinated adult population.

The Panoramic study is open to adults over age 50, or those aged between 18 and 49 who have underlying health conditions that may put them at higher risk for severe Covid-19.