A single dose of the broad-spectrum antibiotic azithromycin didn't change the proportion of US COVID-19 patients reporting symptoms by 14 days, finds a randomized, controlled trial published late last week in JAMA.The study, led by University of California at San Francisco (UCSF) researchers, involved assigning 263 non-hospitalized adult COVID-19 patients to either a 1.2-gram dose of oral azithromycin (171) or a placebo (92) from May 2020 to March 2021.Participants, who had tested positive for COVID-19 within the past 7 days, were followed for as many as 21 days to gauge whether the antibiotic would prevent disease progression by 14 days.