The COVID-19 antiviral drug Molnupiravir helps speed up recovery from the virus but does not reduce the hospitalization or death rate in higher-risk vaccinated adults, a new study has found.

Molnupiravir, from Ridgeback Biotherapeutics and Merck & Co. is used to treat mild to moderate COVID-19 and can be taken at home, twice a day for five days, within five days of symptoms onset.

It works by stopping the virus from replicating, keeping levels low in the body, thus reducing its severity.

The study was published in The Lancet on Dec. 22 and has been peer reviewed.

Between Dec. 8, 2021 and April 27, 2022, more than 25,700 eligible participants in the UK aged 50 or older—or 18 or older with relevant comorbidities—who had been unwell with confirmed COVID-19 for five days or less took part in the study, which was conducted when the Omicron variant was dominant.

Half of the participants were randomly assigned to receive an 800 milligram dose of Molnupiravir twice daily for five days and the other half were assigned to receive usual hospital care only.

The mean age of participants was 56.6 years and 94 percent had received at least three doses of a SARS-CoV-2 vaccine.

Doesn't Reduce Hospital Admissions or Death

Researchers conducted a follow-up of the participants either via an online diary or a telephone call within 28 days. They found that hospitalizations or deaths were recorded in 105 (1 percent) of the 12,529 participants who received Molnupiravir, versus 98 hospitalizations or deaths (1 percent) recorded in the 12,525 participants who were given usual care.