Lufotrelvir (PF-07304814) is an investigational antiviral compound developed for the treatment of COVID-19. It functions as a prodrug that is metabolized in the body to release an active compound targeting the main protease (Mpro or 3CLpro) of SARS-CoV-2, the virus responsible for COVID-19. By inhibiting this key viral enzyme, the drug prevents the virus from replicating inside infected cells.

The compound was designed for intravenous administration, making it suitable for use in hospitalized patients who are unable to take oral medications. Its development focused on providing a therapeutic option for moderate to severe cases of COVID-19, particularly during the early phases of infection when viral replication is highest.

Although clinical development was discontinued due to strategic portfolio decisions and evolving treatment landscapes, lufotrelvir contributed to research efforts in understanding protease inhibition as a viable antiviral strategy. It also served as a foundation for the development of other antiviral agents within the same class.