(PFE/ENTA/PRDS/etc)—Some_patients_may_need_longer_treatment_course_of Paxlovid, according_to_anecdotal info: https://www.bostonglobe.com/2022/04/21/metro/puzzling-phenomenon-patients-report-rebound-covid-19-symptoms-after-taking-antiviral-paxlovid/ The FDA EUA specifies a 5-day treatment course because that’s what PFE tested in its clinical trials—not because 5 days is necessarily optimal.