Mavacamten and Obeticholic Acid: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Mavacamten
Obeticholic Acid
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 mavacamten exposure and an increased risk of mavacamten-related adverse effects
Interaction Deep Dive
Concomitant use of mavacamten with a weak CYP2C19 inhibitor may increase mavacamten exposure and may also increase the risk of adverse effects. Mavacamten AUC was increased by 48% with concomitant use of omeprazole in CYP2C19 normal and rapid metabolizers. In patients on stable therapy with a weak CYP2C19 inhibitor, initiate mavacamten at the usual starting dose of 5 mg orally once daily. In patients treated with mavacamten and initiation with a weak CYP2C19 inhibitor is intended, reduce the mavacamten dose to the next lower daily (mg) dose level (ie, 15 mg to 10 mg; 10 mg to 5 mg; 5 mg to 2.5 mg). Schedule clinical and echocardiographic assessment 4 weeks after inhibitor initiation, and do not up-titrate to the next higher daily (mg) dose level of mavacamten until 12 weeks after inhibitor initiation. In patients on a stable mavacamten dose of 2.5 mg/day, avoid initiation of a concomitant weak CYP2C19 inhibitor (because a lower dose is not available). For short-term use (eg, 1 week), interrupt mavacamten for the duration of treatment with a weak CYP2C19 inhibitor. Mavacamten may be reinitiated at the previous dose immediately on discontinuation of concomitant therapy1.
Why it happens (mechanism)
Inhibition of CYP2C19-mediated metabolism of mavacamten
Literature reports
1 report — tap to read
a) Concomitant use of mavacamten 15 mg with omeprazole (weak CYP2C19 inhibitor) 20 mg once daily increased mavacamten AUC(inf) by 48% with no effect on Cmax in healthy CYP2C19 normal and rapid metabolizers 1.
Common questions
Can I take Mavacamten and Obeticholic Acid together?
Increased mavacamten exposure and an increased risk of mavacamten-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Mavacamten and Obeticholic Acid 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 Mavacamten or Obeticholic Acid 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: CAMZYOS(R) oral capsules, mavacamten oral capsules. Bristol-Myers Squibb Company (per Manufacturer), Princeton, NJ, 2025. DailyMed
Keep reading about Mavacamten
Keep reading about Obeticholic Acid
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