Pfizer has announced that it has launched a large-scale clinical trial of its anti-Covid pill to test its ability to prevent the risk of infection in the environment of a person infected with the disease.
Several companies, such as Merck and Roche, are working on drugs of this type, called antiretrovirals.
Antiretrovirals work by preventing the virus from reproducing. Their application can be twofold: to allow people who are already infected with the disease not to suffer from serious symptoms, but also to prevent people who came in close contact which an infected person not to develop the disease.
In the case of definitive results, "we believe that this treatment can help to stop the virus very early - before it spreads - potentially preventing the symptomatic cases of the disease in those who have been exposed and stopping the onset of infection in others," said Pfizer's scientific director Mikael Dolsten in a statement.
This approach is "complementary" to Covid vaccines, he added.
This new proposed treatment, called PF-07321332, which was developed in the form of an oral pill with a glass of water will see more than 2,600 volunteers aged 18 and over take part in the 2/3 phase clinical trial announced Pfizer yesterday.
Some will take the pill, which will be given twice a day for 5 to 10 days, and others will take placebo.
The drug has already been tested in dozens of people to prove that it is not dangerous to health.