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What the FDA labels say about taking them together

Enzalutamide and rifapentine

Enzalutamide's FDA label (Xtandi) of May 25, 2021 names rifapentine in its drug interactions section; the rifapentine label PlainMeds reads does not name enzalutamide.

Check it at the source: the enzalutamide FDA label on DailyMed (effective July 28, 2026, Astellas Pharma US, Inc.); the rifapentine FDA label on DailyMed (effective February 6, 2026, sanofi-aventis U.S. LLC).

What does the enzalutamide label say about rifapentine?

Xtandi label (Astellas Pharma US, Inc., May 25, 2021), drug interactions

Co-administration of strong CYP3A4 inducers (e.g., carbamazepine, phenobarbital, phenytoin, rifabutin, rifampin, rifapentine) with XTANDI should be avoided if possible.

Source: FDA drug label (Xtandi, NDA213674), Astellas Pharma US, Inc., effective May 25, 2021 (SPL set 381cd215-78c9-4208-8595-7ae7a279b236), via openFDA

Source: FDA drug label (Xtandi), Astellas Pharma US, Inc., effective July 28, 2026 (SPL set b129fdc9-1d8e-425c-a5a9-8a2ed36dfbdf), via openFDA; the full label on DailyMed

What does the rifapentine label say about enzalutamide?

Rifapentine's label (effective February 6, 2026) does not name enzalutamide in these sections. A label lists what its studies and reports found; it is not a complete list.

Source: FDA drug label (Priftin), sanofi-aventis U.S. LLC, effective February 6, 2026 (SPL set 3a64fb70-b85e-43d9-8bcd-7e893f568ae1), 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

0Enzalutamide generic labelers
1Rifapentine generic labelers
EnzalutamideRifapentine
Labeled forProstate cancern/a
Boxed warningNoNo
Pharmacy cost (NADAC)n/a$4.83 per tablet 150 mg tablet
Shortage nowNo current entryResolved

Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)

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