Prescription medicine
Denileukin diftitox Brand names: Lymphir; first approved as Ontak
Denileukin diftitox (Lymphir) is a prescription medicine with an FDA approval on record since 1999. No generic is listed in FDA's NDC Directory.
- No generic listed
- Boxed warning
Check it at the source: the denileukin diftitox FDA label on DailyMed (effective January 23, 2025); the BLA 103767 record on Drugs@FDA; every denileukin diftitox label on DailyMed.
Highlights of the record
FDA label of January 23, 2025; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026
CAPILLARY LEAK SYNDROME.
Capillary leak syndrome (CLS), including life-threatening or fatal reactions, can occur in patients receiving LYMPHIR. Monitor patients for signs and symptoms of CLS during treatment. Withhold LYMPHIR until CLS resolves, or permanently discontinue based on severity [see Dosage and Administration ( 2.1 , 2.4 ) and Warnings and Precautions ( 5.1 )]. WARNING: CAPILLARY LEAK SYNDROME See full prescribing information for complete boxed warning. Capillary leak syndrome (CLS), including life-threatening or fatal reactions, can occur in patients receiving LYMPHIR. Monitor patients for signs and symptoms of CLS during treatment. Withhold LYMPHIR until CLS resolves or permanently discontinue based on severity.
Used for
From the label: indications and usageLYMPHIR is indicated for the treatment of adult patients with relapsed or refractory Stage I-III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy.
Forms and strengths
- 2ml
Injection (powder) (lyophilized) for solution.
On the market
- Earliest approval on file
- February 5, 1999 Ontak, Eisai Inc; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- No generic approved
- Labelers listed (NDC)
- 1 of which 0 under generic applications, 1 under brand applications, repackagers included
Supply and safety
- Pharmacy cost (NADAC)
- Not in the survey
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- No recall recorded
- FAERS reports
- 4 through July 30, 2026
What is denileukin diftitox used for?
From the label: indications and usageLYMPHIR is indicated for the treatment of adult patients with relapsed or refractory Stage I-III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy. LYMPHIR is an IL2-receptor-directed cytotoxin indicated for the treatment of adult patients with relapsed or refractory Stage I-III cutaneous T-cell lymphoma (CTCL) after at least one prior systemic therapy.
Conditions named in the indications of denileukin diftitox's FDA labels, with every medicine labeled for each:
FDA pharmacologic class: CD25-directed Cytotoxin.
Source: FDA drug label (LYMPHIR), Citius Pharmaceuticals, Inc., effective January 23, 2025 (SPL set ac3613d7-4304-40e7-a3f5-adb8a8adca5d), via openFDA; the full label on DailyMed
Is there a generic for denileukin diftitox (Lymphir)?
No generic denileukin diftitox is approved (Drugs@FDA, October 8, 2026).
- 1999 earliest approval on file
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do FAERS reports show for denileukin diftitox?
The FDA Adverse Event Reporting System holds 4 reports that list denileukin diftitox among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 1 are coded as a death and 2 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What else is labeled for the same conditions as denileukin diftitox?
36 other medicines are given the same way (intravenous) and in the same FDA class as denileukin diftitox or labeled mainly for the same use (leukemia, lymphoma and myeloma), the same class first. Leukemia, lymphoma and myeloma lists all 98 medicines labeled for it, by any route. The first 8 are below. They are listed as records, not as substitutes: whether one can replace another is a prescriber's decision.
| Medicine | Shared indication | Generic labelers (intravenous) | Pharmacy cost | Shortage |
|---|---|---|---|---|
| Cyclophosphamide | Leukemia, lymphoma and myeloma | 15 labelers | n/a | No current entry |
| Doxorubicin | Leukemia, lymphoma and myeloma | 16 labelers | n/a | No current entry |
| Bortezomib | Leukemia, lymphoma and myeloma | 22 labelers | n/a | No current entry |
| Arsenic trioxide | Leukemia, lymphoma and myeloma | 16 labelers | n/a | A presentation being discontinued |
| Bendamustine | Leukemia, lymphoma and myeloma | 4 labelers | n/a | A presentation being discontinued |
| Nelarabine | Leukemia, lymphoma and myeloma | 12 labelers | n/a | No current entry |
| Idarubicin | Leukemia, lymphoma and myeloma | 2 labelers | n/a | No current entry |
| Clofarabine | Leukemia, lymphoma and myeloma | 9 labelers | n/a | No current entry |
Source: FDA drug labels (indications), NDC Directory, NADAC of October 7, 2026, FDA shortages (October 8, 2026)
What next?
- Denileukin diftitox side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other