Pfizer's updated results for its experimental treatment for Covid-19 showed it cut the risk of hospitalization or death by 89% if given to high-risk adults within a few days of their first symptoms, the company announced in a news release Tuesday.

Pfizer hopes it can eventually offer the pills, under the name Paxlovid, for people to take at home before they get sick enough to go to the hospital. Paxlovid combines a new antiviral drug named nirmatrelvir and an older one called ritonavir.

After a month of follow-up, the study found five hospitalizations and no deaths among 697 people who received the drug within the first three days of symptoms. Among 682 who received placebo, 44 were hospitalized, including 9 who died. All of the adults in this study were unvaccinated.