| Interaction Color Code | Clinical Bottom Line | Clinical Effects | Drug 1 effect | Drug 2 dose | Drug 2 effect | Management | |
|---|---|---|---|---|---|---|---|
| Fostemsavir RFB + RTV 1 | Yellow: Adjust dosing | Adjust dosing to avoid increased levels of rifabutin | Temsavir Cmax increased 50%, AUC increased 66%, Cmin increased 158% |
RFB 150 mg once daily, RTV 100 mg once daily | Not reported |
Use standard dose rifabutin if coadministering with fostemsavir. If using fostemsavir in combination with a ritonavir boosted protease inhibitor, lower rifabutin dose to 150 mg daily. |
