Elexacaftor, tezacaftor, and ivacaftor and Nirmatrelvir and ritonavir interaction
Elexacaftor, tezacaftor, and ivacaftor and Nirmatrelvir and ritonavir: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Nirmatrelvir and ritonavir (Paxlovid) label · effective 2026-02-19
…delayed offset of the recently discontinued CYP3A inducer [see Drug Interactions (7.3) ] : • Anticancer drugs: apalutamide, enzalutamide • Anticonvulsant: carbamazepine, phenobarbital, primidone, phenytoin • Antimycobacterials: rifampin, rifapentine • Cystic fibrosis transmembrane conductance regulator potentiators: lumacaftor/ivacaftor • Herbal products: St.
Cystic fibrosis transmembrane conductance regulator potentiators lumacaftor/ivacaftor ↓ nirmatrelvir/ritonavir Co-administration contraindicated due to potential loss of virologic response and possible resistance [see Contraindications (4) ] .
Cystic fibrosis transmembrane conductance regulator potentiators ivacaftor elexacaftor/tezacaftor/ ivacaftor tezacaftor/ivacaftor ↑ ivacaftor ↑ elexacaftor/tezacaftor/ ivacaftor ↑ tezacaftor/ivacaftor Reduce dosage when co-administered with PAXLOVID.
From the Elexacaftor, tezacaftor, and ivacaftor (Trikafta) label · effective 2026-06-22
Concomitant Use with CYP3A Inhibitors Exposure to elexacaftor, tezacaftor and ivacaftor are increased when used concomitantly with strong or moderate CYP3A inhibitors.
Therefore, the dose of TRIKAFTA should be reduced when used concomitantly with moderate or strong CYP3A inhibitors [see Dosage and Administration (2.4) , Drug Interactions (7.1) and Clinical Pharmacology (12.3) ] .
Strong or moderate CYP3A inhibitors: Reduce TRIKAFTA dosage when used concomitantly.
John's wort ( Hypericum perforatum ) Strong or Moderate CYP3A Inhibitors The dosage of TRIKAFTA should be reduced when used concomitantly with strong CYP3A inhibitors [see Dosage and Administration (2.4) and Warnings and Precautions (5.6) ] .
Concomitant use with itraconazole, a strong CYP3A inhibitor, increased elexacaftor AUC by 2.8-fold and tezacaftor AUC by 4.0- to 4.5-fold.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.