What the FDA labels say about taking them together
Ivacaftor/lumacaftor and nirmatrelvir/ritonavir
Nirmatrelvir/ritonavir's FDA label of February 19, 2026 names ivacaftor/lumacaftor in its contraindications section; the ivacaftor/lumacaftor label PlainMeds reads does not name nirmatrelvir/ritonavir. The nirmatrelvir/ritonavir label: “Cystic fibrosis transmembrane conductance regulator potentiators lumacaftor/ivacaftor ↓ nirmatrelvir/ritonavir Co-administration contraindicated due to potential loss of virologic response and possible resistance.”
Check it at the source: the ivacaftor/lumacaftor FDA label on DailyMed (effective March 24, 2026, Vertex Pharmaceuticals Incorporated); the nirmatrelvir/ritonavir FDA label on DailyMed (effective February 19, 2026, Pfizer Laboratories Div Pfizer Inc).
What does the ivacaftor/lumacaftor label say about nirmatrelvir/ritonavir?
Ivacaftor/lumacaftor's label (effective March 24, 2026) does not name nirmatrelvir/ritonavir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (ORKAMBI), Vertex Pharmaceuticals Incorporated, effective March 24, 2026 (SPL set 3fc1c40e-cfac-47a1-9e1a-61ead3570600), via openFDA; the full label on DailyMed
What does the nirmatrelvir/ritonavir label say about ivacaftor/lumacaftor?
Nirmatrelvir/ritonavir label, contraindicationsCystic fibrosis transmembrane conductance regulator potentiators: lumacaftor/ivacaftor
Nirmatrelvir/ritonavir label, drug interactionsCystic 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) ].
Source: FDA drug label (Paxlovid), Pfizer Laboratories Div Pfizer Inc, effective February 19, 2026 (SPL set 8a99d6d6-fd9e-45bb-b1bf-48c7f761232a), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Ivacaftor/lumacaftor | Nirmatrelvir/ritonavir | |
|---|---|---|
| Labeled for | n/a | COVID-19 |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $49.24 per unit 300-100 mg dose pack |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once