Kliniske interaktionsstudier med rifampicin (en CYP 3A4 inducer) og ketoconazol (CYP 3A4 hæmmer) viste ingen klinisk relevant ændring i fulvestrant clearance.
Clinical interaction studies with rifampicin (inducer of CYP3A4) and ketoconazole (inhibitor of CYP3A4) showed no clinically relevant change in fulvestrant clearance.