WASHINGTON: Pfizer said on Friday that a clinical trial of its pill to treat Covid-19 had shown it is highly effective.
The drug called Paxlovid is the second anti-Covid pill after that of Merck, which is actually an influenza medicine rebranded to fight the coronavirus. Pfizer said its medication had been created specifically to fight Covid.
The drug achieved an 89% reduction in risk of hospitalisation or death among adult patients with Covid who are at high risk of progressing to severe illness, the US company said.
The results from the middle- to late-stage clinical trial were so strong that Pfizer will stop recruiting new people for the trial, the company said.
It will submit the data to the Food and Drug Administration as soon as possible as part of its "rolling submission" for Emergency Use Authorisation.
"Today's news is a real game-changer in the global efforts to halt the devastation of this pandemic," said Pfizer CEO Albert Bourla.
"These data suggest that our oral antiviral candidate, if approved or authorised by regulatory authorities, has the potential to save patients’ lives, reduce the severity of Covid-19 infections, and eliminate up to nine out of 10 hospitalisations."
The main analysis of the data looked at numbers from 1,219 adults in North and South America, Europe, Africa and Asia.
Several companies are working on oral antivirals, which would mimic what the drug Tamiflu does for influenza and prevent the disease from progressing to severe.
Pfizer started developing its drug in March 2020.
Britain on Thursday became the first country to approve an anti-Covid pill, as it okayed the use of Merck's antiviral drug called molnupiravir to treat patients suffering from mild to moderate coronavirus.
Pfizer's product is known as a "protease inhibitor" and has been shown in lab testing to jam up the virus' replication machinery. If it works in real life, it will likely only be effective at the early stages of infection.
By the time Covid progresses to a severe disease, the virus has largely stopped replicating and patients suffer from an overactive immune response.
A simple pill to treat the coronavirus has been sought since the start of the pandemic.
Until now, Covid therapeutics such as monoclonal antibodies and remdesivir — a drug made by Gilead and authorised for use in the EU under the name Veklury — have been administered intravenously.
Molnupiravir was initially developed as an inhibitor of influenza and respiratory syncytial virus — two other important acute respiratory infections — by a team at Emory University in Atlanta, Georgia.
Britain, which has been one of the countries hardest hit by the pandemic, announced on Oct 20 that it had ordered 480,000 doses of molnupiravir.