THINGS TO KNOW

■ The pills are meant for people who are sick with Covid but are not in the hospital.

■ The pills are designed to be taken as soon as possible once a person shows symptoms of having Covid.

■ Merck said the drug cut the risk of hospitalisation or death in half.

■ The 50 per cent efficacy is lower than monoclonal antibodies.

■ Experts said the new antiviral pills will most likely have a bigger overall impact on Covid than the cumbersome antibodies.

■ Merck is planning to seek emergency authorisation from the Food and Drug Administration as soon as possible. Regulators could then authorize the drug before the end of this year, if all goes well.