Repotrectinib and Colchicine: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Colchicine
Repotrectinib
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.
You've been prescribed colchicine (for gout or a similar condition) along with repotrectinib (Augtyro), a cancer medicine. Here's what's happening: repotrectinib speeds up an enzyme in your body called CYP3A4, which is the same enzyme that breaks down colchicine. When that enzyme works faster, your body clears colchicine more quickly, so there may be less of it working for you. That means your colchicine might not control your symptoms as well as it normally would.
The good news is your care team can handle this. They may adjust your colchicine dose or watch your response more closely. Please don't change anything on your own, but do let your pharmacist or doctor know you're taking both.
Effect: Repotrectinib is a moderate-to-strong CYP3A4 inducer; colchicine is a CYP3A4 substrate. Concomitant use is expected to increase colchicine metabolism, lowering its exposure (AUC/Cmax) and potentially reducing efficacy.
- Direction: Reduced colchicine effect (induction, not a prodrug scenario).
- Magnitude: No colchicine-specific data; index substrate midazolam showed AUC0-inf down 69% and Cmax down 48%.
- Onset: Unspecified; enzyme induction is typically delayed (days).
- Evidence: Probable. Severity: major.
Management: Avoid concomitant use with narrow-therapeutic-index CYP3A4 substrates where feasible. If unavoidable, the colchicine dose may need to be increased and individualized, with closer monitoring of clinical response.
What happens
Reduced CYP3A4 substrates exposure and reduced efficacy of CYP3A4 substrates
Interaction Deep Dive
Because repotrectinib acts as a CYP3A4 inducer, its coadministration with CYP3A4 substrates that have a narrow therapeutic index should be avoided. When repotrectinib is used together with CYP3A4 substrates, the exposure of those substrates is lowered, and for drugs in which even small concentration reductions can compromise effectiveness, this poses a concern. Should concurrent use be unavoidable, the dose of the CYP3A4 substrate should be raised as needed. Drug interaction studies showed that midazolam (a CYP3A4 substrate) had its AUC (0 to inf) fall by 69% and its Cmax fall by 48% when given with repotrectinib in subjects who had received 160 mg of repotrectinib once daily for 14 days and then 160 mg twice daily for 7 days1.
Why it happens (mechanism)
Induction of CYP3A4-substrate metabolism by repotrectinib
How to manage this interaction
Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. Because repotrectinib can lower how much colchicine stays active in your body, your team is the one to make any changes.
- Your colchicine dose may need to be adjusted and individualized by your care team if the two are used together.
- They may monitor you more closely to see whether your colchicine is still working the way it should.
- Tell your prescriber if your original symptoms (such as gout flares) come back or feel less controlled.
Always check with your pharmacist or doctor before starting, stopping, or changing either medicine.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In the drug interaction studies, midazolam (a CYP3A4 substrate) showed a 69% reduction in AUC (0 to inf) and a 48% reduction in Cmax when used concomitantly in subjects who had previously received 160 mg repotrectinib once daily for 14 days followed by 160 mg twice daily for 7 days 1.
Common questions
Can I take Repotrectinib and Colchicine together?
Repotrectinib can speed up the breakdown of colchicine, making colchicine less effective; keep taking both as prescribed and let your care team adjust the dose or monitor your response. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Repotrectinib and Colchicine 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 is the Repotrectinib and Colchicine interaction managed?
Keep taking both medicines exactly as prescribed unless your care team tells you otherwise. Because repotrectinib can lower how much colchicine stays active in your body, your team is the one to make any changes. Your colchicine dose may need to be adjusted and individualized by your care team if the two are used together. They may monitor you more closely to see whether your colchicine is still w… Management is individual — always follow your own care team's guidance.
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 Repotrectinib or Colchicine 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: AUGTYRO(TM) oral capsules, repotrectinib oral capsules. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2023. DailyMed
Keep reading about Colchicine
Keep reading about Repotrectinib
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