THE MULTINATIONAL SCIENCE and technology company Merck has said that its experimental Covid-19 pill reduced stays in hospital and deaths by half in people recently infected with the coronavirus.

The company said it would soon ask health officials around the world to authorise its use.

If cleared, Merck’s drug would be the first pill shown to treat Covid-19, a potentially major advance in efforts to fight the pandemic.

Merck and its partner Ridgeback Biotherapeutics said early results showed patients who received the drug, called molnupiravir, within five days of Covid-19 symptoms had about half the rate of stays in hospital and death as patients who received a dummy pill.

The study tracked 775 adults with mild-to-moderate Covid-19 who were considered higher risk for severe disease due to health problems such as obesity, diabetes or heart disease.

Among patients taking molnupiravir, 7.3% were either admitted to hospital or died at the end of 30 days, compared with 14.1% of those getting the dummy pill.

There were no deaths in the drug group after that time period compared with eight deaths in the placebo group, according to Merck.

The results were released by the company and have not been peer reviewed. Merck said it plans to present them at a future medical meeting.

An independent group of medical experts monitoring the trial recommended stopping it early because the interim results were so strong.

“It exceeded what I thought the drug might be able to do in this clinical trial,” said Dr Dean Li, vice president of Merck research. “When you see a 50% reduction in hospitalization or death that’s a substantial clinical impact.”

Side effects were reported by both groups in the Merck trial, but they were slightly more common among the group that received a dummy pill. The company did not specify the problems.

Earlier study results showed the drug did not benefit patients who were already in hospital with severe disease.

Health experts including the US infectious disease expert Dr Anthony Fauci have long called for a convenient pill that patients could take when Covid-19 symptoms first appear. Such medications are seen as key to controlling future waves of infection and reducing the impact of the pandemic.

Merck’s pill works by interfering with an enzyme the coronavirus uses to copy its genetic code and reproduce itself. It has shown similar activity against other viruses.

Several other companies, including Pfizer and Roche, are studying similar drugs that could report results in the coming weeks and months.