When SARS-CoV-2 enters a cell, the virus needs to replicate its RNA genome to form new viruses. Monupiraviris incorporated into the RNA strand and mutates in a random fashion, so the virus then replicates in a mutated fashion, and over time it causes more mutations that eventually kill the virus.
Because mutations accumulate randomly, it is difficult for viruses to evolve resistance to monupavir, meaning the drug is effective against variants of COVID-19. A Phase III trial, conducted in more than 170 test centers around the world. Selected patients needed to have at least one risk factor associated with poor disease outcomes (such as diabetes or heart disease) and received monupiravir or placebo after mild to moderate symptoms were observed. Monupavir reduced risk of hospitalization or death, according to an interim analysis evaluating outcomes in 775 subjects. The trials were conducted in patients with mild symptoms who were not hospitalized.