An antiviral pill was found to reduce hospitalisations and deaths by half in patients newly diagnosed with Covid-19, according to results announced on Friday.
If approved, the drug made by the US firm Merck and Ridgeback Biotherapeutics would be the first simple oral medication shown to be effective against Covid-19, which would mark a crucial advance in the fight against the pandemic. Other drugs, such as remdesivir, have been shown to be effective if given early, but all currently approved treatments need to be given as injections or IV infusions.
Merck said it would apply for emergency use authorisation for the drug in the US within the next two weeks and seek approval in several other countries.
The trial tracked 775 adults with mild to moderate Covid, who were considered higher risk for severe disease owing to health problems such as obesity, diabetes or heart disease. Half were given a five-day course of the pill, called molnupiravir. In the placebo group, 53 patients (14%) were hospitalised compared with only 28 (7%) of those who received the drug. There were no deaths in the drug group after that time period compared with eight deaths in the placebo group, according to Merck.
The data from the study was made public in a press release and has not yet been peer-reviewed. However, an independent group of medical experts monitoring the trial recommended stopping it early because the interim results were so encouraging.
“It exceeded what I thought the drug might be able to do in this clinical trial,” said Dean Li, the vice-president of Merck research. “When you see a 50% reduction in hospitalisation or death that’s a substantial clinical impact.”
Only limited information on side-effects was made public in the press release, but the companies said rates were similar between the placebo group and the treated group. An adverse event, or bad outcome, occurred in 35% of those who received molnupiravir and 40% of those who received placebo. Only 1.3% of participants who received the drug discontinued treatment because of an adverse event, compared with 3.4% who discontinued the placebo.
A convenient pill that patients could take when Covid symptoms first appear has long been viewed as a crucial goal in controlling future waves of infection and reducing the ongoing impact of the pandemic.