What the FDA labels say about taking them together
Aficamten and rifampin
Aficamten's FDA label of December 16, 2025 names rifampin in its contraindications section; the rifampin label PlainMeds reads does not name aficamten. The aficamten label: “CONTRAINDICATIONS MYQORZO is contraindicated with concomitant use of rifampin.”
Check it at the source: the aficamten FDA label on DailyMed (effective December 16, 2025, Cytokinetics Inc.); the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.).
What does the aficamten label say about rifampin?
Aficamten label, contraindicationsCONTRAINDICATIONS MYQORZO is contraindicated with concomitant use of rifampin [see Warnings and Precautions (5.3) and Drug Interactions (7.1) ].
Aficamten label, drug interactionsCYP Inducers Rifampin Clinical Impact Rifampin is a strong CYP3A inducer, strong CYP2C19 inducer, and moderate CYP2C9 inducer. Coadministration of rifampin decreases aficamten exposure, which may reduce the effectiveness of MYQORZO [see Contraindications (4) and Clinical Pharmacology (12.3) ]. Prevention of Management Concomitant use with rifampin is contraindicated.
Aficamten label, warnings and precautionsConversely, initiation of medications that induce P450 pathways of MYQORZO (e.g., rifampin, moderate-to-strong CYP3A inducers) may lead to decreased blood concentrations of aficamten and potential loss of effectiveness [see Contraindications (4) and Drug Interactions (7.1) ].
Source: FDA drug label (MYQORZO), Cytokinetics Inc., effective December 16, 2025 (SPL set fd778507-1274-4d1a-a659-5431d55c543a), via openFDA; the full label on DailyMed
What does the rifampin label say about aficamten?
Rifampin's label (effective February 11, 2026) does not name aficamten in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (rifampin), Lupin Pharmaceuticals, Inc., effective February 11, 2026 (SPL set b56004f0-f23d-47f6-80c7-39884fccbccc), 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
| Aficamten | Rifampin | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | n/a | $0.679 per capsule 300 mg capsule |
| Shortage now | No current entry | In shortage |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once