Maraviroc and Amprenavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Amprenavir
No brand names on recordMaraviroc
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 maraviroc concentrations
Interaction Deep Dive
Maraviroc is a substrate of CYP3A4 and a P-glycoprotein (P-gp) drug transporter. Concomitant administration with a strong CYP3A4 or P-gp transport inhibitor, such as amprenavir, may increase maraviroc concentrations. Although not studied with amprenavir, coadministration of ritonavir-boosted fosamprenavir with maraviroc increased the minimum concentration, AUC, and Cmax of maraviroc. Use caution if maraviroc is given with amprenavir (with or without a strong CYP3A inducer) and adjust the maraviroc dose to 150 mg twice daily. Monitor patients for increased maraviroc adverse events (eg, elevated liver transaminases, dizziness, rash)1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated maraviroc metabolism
Literature reports
1 report — tap to read
a) Concomitant administration of fosamprenavir/ritonavir and maraviroc resulted in increased maraviroc AUC and plasma concentrations. When fosamprenavir 700 mg/ritonavir 100 mg twice daily was administered concurrently with maraviroc 300 mg twice daily in 14 patients, the ratio of maraviroc pharmacokinetic parameters with fosamprenavir/ritonavir to without fosamprenavir/ritonavir was: minimum concentration (Cmin) 4.74 (90% CI, 4.03 to 5.57), AUC 2.49 (90% CI, 2.19 to 2.82), and Cmax 1.52 (90% CI, 1.27 to 1.82). When concomitant administration of fosamprenavir 1400 mg/ritonavir 100 mg once daily was administered with maraviroc 300 mg once daily in 14 patients, the ratio of maraviroc pharmacokinetic parameters with fosamprenavir/ritonavir to without fosamprenavir/ritonavir was: Cmin 1.8 (90% CI, 1.53 to 2.13), AUC 2.26 (90% CI, 1.99 to 2.58), and Cmax 1.45 (90% CI, 1.2 to 1.74) 1.
Common questions
Can I take Maraviroc and Amprenavir together?
Increased maraviroc concentrations Always confirm with your pharmacist or prescriber before making any change.
How serious is the Maraviroc and Amprenavir interaction?
It is rated moderate. Can be significant — usually manageable with 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Maraviroc or Amprenavir 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: SELZENTRY(R) oral tablets, maraviroc oral tablets. ViiV Healthcare (per FDA), Research Triangle Park, NC, 2013. DailyMed
Keep reading about Amprenavir
Keep reading about Maraviroc
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