What the FDA labels say about taking them together
Cyclophosphamide and pentostatin
Cyclophosphamide's FDA label (Frindovyx) of August 26, 2026 names pentostatin in its drug interactions section, and pentostatin's label names cyclophosphamide too. The cyclophosphamide label: “Toxicity: Increased cardiotoxicity; Drugs: Anthracyclines Cytarabine Pentostatin Radiation therapy of the cardiac region Trastuzumab”
Check it at the source: the cyclophosphamide FDA label on DailyMed (effective January 19, 2026, Amneal Pharmaceuticals LLC); the pentostatin FDA label on DailyMed (effective July 1, 2026, Hospira, Inc.).
What does the cyclophosphamide label say about pentostatin?
Frindovyx label (AVYXA Pharma, LLC, August 26, 2026), drug interactionsACE inhibitors can cause leukopenia. ● Natalizumab ● Paclitaxel: Increased hematotoxicity has been reported when cyclophosphamide was administered after paclitaxel infusion. ● Thiazide diuretics ● Zidovudine Increased cardiotoxicity ● Anthracyclines ● Cytarabine ● Pentostatin ● Radiation therapy of the cardiac region ● Trastuzumab Increased pulmonary toxicity ● Amiodarone ● G-CSF, GM-CSF (granulocyte colony-stimulating factor, granulocyte macrophage colony-stimulating factor) Increased nephrotoxicity ● Amphotericin B ● Indomethacin:
Cyclophosphamide label (Eugia US LLC, April 21, 2025), drug interactionsToxicity: Increased cardiotoxicity; Drugs: Anthracyclines Cytarabine Pentostatin Radiation therapy of the cardiac region Trastuzumab
Source: FDA drug label (Frindovyx, NDA210852), AVYXA Pharma, LLC, effective August 26, 2026 (SPL set 5ad8ea65-4c98-487a-9c8d-df778765ec5e), via openFDA
Source: FDA drug label (Cyclophosphamide, NDA210735), Eugia US LLC, effective April 21, 2025 (SPL set 3c1eb470-0bba-457d-94e3-b9508f0d398a), via openFDA
Source: FDA drug label (Cyclophosphamide), Amneal Pharmaceuticals LLC, effective January 19, 2026 (SPL set 520bfe39-dfd5-4a20-9a37-80078afded0d), via openFDA; the full label on DailyMed
What does the pentostatin label say about cyclophosphamide?
Pentostatin label, drug interactionsAcute pulmonary edema and hypotension, leading to death, have been reported in the literature in patients treated with pentostatin in combination with carmustine, etoposide and high dose cyclophosphamide as part of the ablative regimen for bone marrow transplant.
Source: FDA drug label (Nipent), Hospira, Inc., effective July 1, 2026 (SPL set 674e0e6d-46ed-4868-9196-04019d667716), 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
| Cyclophosphamide | Pentostatin | |
|---|---|---|
| Labeled for | Leukemia, lymphoma and myeloma | Leukemia, lymphoma and myeloma |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $1.67 per capsule 50 mg capsule | n/a |
| 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