We have downgraded the interaction between sofosbuvir and rifabutin from red to yellow, due to the publication of new data in the European Summary of Product Characteristics.
"Coadministration of sofosbuvir with rifabutin decreased sofosbuvir Cmax by 56% and AUC by 24%. GS-331007 Cmax increased by 15% and AUC by 3% (induction of P-gp). No dose adjustment of sofosbuvir is required when concomitantly used with rifabutin."
Sovaldi Summary of Product Characteristics, Gilead Sciences, May 2021.