Maraviroc and Ritlecitinib: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ritlecitinib
Maraviroc
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased CYP3A substrate exposure and an increased risk of CYP3A substrate-related adverse reactions
Interaction Deep Dive
Concomitant use of sensitive CYP3A substrates with ritlecitinib increases exposure of CYP3A substrates, which may increase the risk of adverse reactions related to these substrates. Consider additional monitoring and dosage adjustments where small concentration changes may lead to serious adverse reactions when used with ritlecitinib. Concomitant use of 200 mg once daily dose of ritlecitinib for 11 days with midazolam (a sensitive CYP3A substrate) increased the AUC and Cmax of midazolam by 2.69-fold and 1.81-fold respectively1.
Why it happens (mechanism)
Inhibition of CYP3A-substrate metabolism by ritlecitinib
Literature reports
1 report — tap to read
a) Concomitant use of 200 mg once daily dose of ritlecitinib for 11 days with midazolam (a sensitive CYP3A substrate) increased the AUC(inf) and Cmax of midazolam by 2.69-fold and 1.81-fold respectively 1.
Common questions
Can I take Maraviroc and Ritlecitinib together?
Increased CYP3A substrate exposure and an increased risk of CYP3A substrate-related adverse reactions Always confirm with your pharmacist or prescriber before making any change.
How serious is the Maraviroc and Ritlecitinib interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Maraviroc or Ritlecitinib need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: LITFULO(TM) oral capsules, ritlecitinib oral capsules. Pfizer Labs (per FDA), New York, NY, 2023. DailyMed
Keep reading about Ritlecitinib
Keep reading about Maraviroc
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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