The oral Covid-19 drug molnupiravir eliminates the SARS-CoV-2 virus in its active infectious phase by the third day from the start of taking it, reveals a study to be presented at the European Congress of Clinical Microbiology and Infectious Diseases next week.

"Many patients" who received a placebo took up to five days to eliminate it, and in some cases longer, also explains the study released this Thursday by the US pharmaceutical company Merck Sharp & Dohme (MSD), the manufacturer of this drug.

The trial confirmed the drug's superiority over placebo in non-hospitalized adults with mild or moderate Covid-19 and at risk of progression to severe disease if therapy was started within five days of symptom onset, The New England Journal of Medicine revealed.

The World Health Organization had released on March 3 that molnupiravir was on its list of recommended treatments against covid-19, and its emergency use was also approved for countries such as the United States, the United Kingdom, Australia, and Japan. This drug is an antiviral that should be administered quickly after the onset of symptoms and taken for five days to prevent the virus from replicating.

According to data released Thursday, trial participants underwent PCR testing to determine SARS-CoV-2 viral loads from nasopharyngeal swabs collected on days 1 (start), 3, 5 (end of treatment), 10, 15 and 29. By day 3 of treatment, none of the 92 participants taking molnupiravir had detectable active-phase SARS-CoV-2, compared with 21.8% (20 of 96) of participants taking a placebo.

After five days, the patients targeted for treatment remained virus-free, while in the other group it was still detected in 2.2%. Finally, at day ten, none of the participants in both groups were positive for covid-19.

This analysis confirmed previous observations showing that a five-day treatment with molnupiravir, taken twice daily, produces "a faster decline in viral load and a faster elimination of the infectious virus than placebo," MSD maintained in a statement.