Impact of Rifabutin on the Pharmacokinetics of Elexacaftor/Tezacaftor/Ivacaftor

Trikafta (Elexacaftor \[ELX\], Tezacaftor \[TEZ\], Ivacaftor\[IVA\]) is contraindicated with concomitant use of strong inducers as co-administration of rifampin decreased the area-under-the concentration time curve (AUC) of IVA by 89%, creating a therapeutic challenge to the treatment of non-tuberculosis mycobacteria (NTM) infection in people with cystic fibrosis (CF). While rifabutin also induces CYP3A4 activity, its effects appear to be more moderate when compared with rifampin. Therefore, we hypothesize that rifabutin can be co-administered with an adjusted dose of ELX/TEZ/IVA in patients being treated for NTM pulmonary disease.