I separate farmakokinetiske interaktionsstudier medførte samtidig administration af ritonavir (potent CYP3A4- hæmmer) eller saquinavir i kombination med en støddosis af ritonavir eller rifampicin (potent CYP3A4- induktor) ingen klinisk signifikante ændringer af enfuvirtids farmakokinetik.
In separate pharmacokinetic interaction studies, co-administration of ritonavir (potent CYP3A4 inhibitor) or saquinavir in combination with a booster dose of ritonavir or rifampicin (potent CYP34A inducer) did not result in clinically significant changes of the pharmacokinetics of enfuvirtide.