Pfizer's at-home COVID-19 drug significantly lowered hospitalization and death rates among older adults but couldn't match that efficacy in middle-aged adults, a study of more than 100,000 patients found.
The research, published Aug. 24 in The New England Journal of Medicine, tracked the efficacy of one of the drugs in the Paxlovid cocktail in Israeli adults 40 and older who were at high risk and tested positive for COVID-19 as omicron surged in the first three months of 2022. Previous Paxlovid studies were dated by COVID-19's standards because they happened during past variant surges, such as delta.
With nirmatrelvir — one of the two drugs used in Paxlovid, a five-day regimen authorized at the end of 2021 — no benefit was found among adults between 40 and 64 years old.
Study participants 65 and older who took nirmatrelvir had a lower risk of hospitalization and death from COVID-19 if they were inoculated against SARS-CoV-2, according to the research.
The use of the antiviral treatment seems to be decreasing as Pfizer recently halted its standard-risk clinical trials for Paxlovid and its popularity slows.