Drug reference

denileukin diftitox

Recombinant IL-2–diphtheria toxin fusion protein (antineoplastic)

START

9 mcg/kg/day IV days 1–5 of 21-day cycle (premedicate)

TYPICAL MAX

9 mcg/kg/day on days 1–5 per cycle

STOP IF

Capillary leak (hypotension/oedema), severe infusion reaction, or visual loss

WATCH

Albumin/weight/BP (capillary leak), LFTs, visual symptoms

CDSCO approvedATC L01XX29

Renal dose adjustmenteGFR mL/min/1.73m²

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours

ONSET: 6min · infusion start
PEAK: 1h · end infusion
t½: 1.3h · t½ ~80 min
DURATION: 3w · q21d cycle

EXCRETION

Proteolytic catabolism; not excreted intact

route + CYP

INTERACTIONS

12 major

SEVERE in our sources

PREGNANCY

Can cause fetal harm — avoid; effective contraception required.

FDA category + note

Top interactionssee all 12 →

AdalimumabSevereDatabaseDDInter
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Mechanism

Interleukin-2 fused to diphtheria toxin fragments; binds the IL-2 receptor (CD25) on malignant T cells, is internalised, and the diphtheria-toxin moiety inhibits protein synthesis (ADP-ribosylation of EF-2), causing apoptosis.

Indications

Relapsed/refractory CD25-expressing cutaneous T-cell lymphoma

Dosing

Adult: 9 micrograms/kg/day IV over ≥60 min on days 1–5 of a 21-day cycle (per current relaunched product labelling).
Pediatric: Not established.
Renal adjustment: No specific adjustment (limited data).
Hepatic adjustment: No specific adjustment; monitor LFTs.
Geriatric: Limited data; monitor closely.
Max dose: 9 micrograms/kg/day on days 1–5 per 21-day cycle

Pharmacokinetics

Onset

Antitumour effect over cycles

Peak effect

End of infusion

Duration

21-day cycle (5-day dosing)

Half-life

~70–80 min (distribution); rapid clearance

Bioavailability

IV 100%

Protein binding

Not applicable (fusion protein)

Metabolism

Proteolytic catabolism

Excretion

Catabolised (not renally/hepatically excreted intact)

Contraindications

Severe hypersensitivity to denileukin/diphtheria toxin/IL-2
Caution: pre-existing low albumin (capillary leak risk), cardiac disease

Side effects

Common

Infusion reactionsPyrexia/chillsNauseaFatigueRashTransaminase elevation

Serious

Capillary leak syndrome (hypotension, oedema, hypoalbuminaemia — boxed)
Severe infusion/hypersensitivity reactions (boxed)
Visual loss/colour-vision changes
Thrombotic events
Hepatotoxicity

Pregnancy & lactation

Pregnancy

Can cause fetal harm — avoid; effective contraception required.

Lactation

Avoid breastfeeding during therapy.