Coadministration with Delstrigo has not been studied. Coadministration of doravirine and the sensitive CYP3A4 substrate midazolam decreased midazolam exposure by 18%. Tacrolimus is metabolized by CYP3A4 and a decrease in tacrolimus exposure cannot be excluded. No effect on doravirine or lamivudine is expected, and there was no clinically significant pharmacokinetic interaction when tenofovir-DF (300 mg once daily) was coadministered with tacrolimus (0.05 mg/kg twice daily for 7 days). Monitoring of tacrolimus blood concentrations is recommended as the dose may need to be adjusted.