%0 Journal Article %T Sofosbuvir Off-label Treatment of Yellow Fever Patients During an Outbreak in Brazil, 2018: A Cohort Study. %A Rezende IM %A Mendonça DC %A Costa TA %A de Oliveria GFG %A Arruda MS %A Gonçalves AP %A Alves PA %A Calzavara-Silva CE %A Martins-Filho OA %A Teixeira-Carvalho A %A Bonjardim CA %A Monath TP %A LaBeaud AD %A Drumond BP %A Pascoal-Xavier MA %A Pereira LS %A Ramalho DB %J Open Forum Infect Dis %V 11 %N 6 %D 2024 Jun %M 38933737 %F 4.423 %R 10.1093/ofid/ofae312 %X We enrolled 21 patients with laboratory-confirmed yellow fever (YF), hospitalized at Eduardo de Menezes Hospital, Brazil, to be treated with sofosbuvir, a drug approved for hepatitis C. Given the absence of specific YF antiviral treatments, the off-label nonrandomized sofosbuvir treatment aimed to address high disease severity and the risk of fatal outcomes. Patients received a daily dose of 400 mg sofosbuvir from 4 to 10 days post-symptom onset. YF viral load (VL) comparisons were made between treated and nontreated patients who either survived or died. The genomic VL for the treated group steadily decreased after day 7 post-symptom onset, suggesting that sofosbuvir might reduce YF VL. This study underscores the urgent need for YF antiviral therapies, advocating for randomized clinical trials to further explore sofosbuvir's role in YF treatment.