Drug reference

Cladribine

Purine nucleoside analogue (antineoplastic / immunomodulator) · Antineoplastic; Immunosuppressant

START

HCL: 0.09 mg/kg/day IV ×7 days. MS: weight-based annual courses

TYPICAL MAX

MS cumulative 3.5 mg/kg over 2 years

STOP IF

Severe infection, prolonged grade 4 lymphopenia, or PML signs

WATCH

Lymphocyte count, infection (incl. PML), LFTs; screen TB/HBV/HIV

CDSCO approvedSchedule HATC L01BB04

Dose laddermg/d

Renal dose adjustmenteGFR mL/min/1.73m²

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours

ONSET: 30min · absorption
PEAK: 1h · Tmax
t½: 10h · t½
DURATION: 1w · course/effect

EXCRETION

Renal — substantial unchanged

route + CYP

INTERACTIONS

12 major

SEVERE in our sources

PREGNANCY

Contraindicated — fetal harm; contraception during and 6 months after.

FDA category + note

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Mechanism

Chlorinated deoxyadenosine analogue resistant to adenosine deaminase; phosphorylated by deoxycytidine kinase to active triphosphate that accumulates in lymphocytes, causing DNA strand breaks and apoptosis — selectively lymphocytotoxic.

Indications

Hairy cell leukaemiaRelapsing multiple sclerosis (oral tablet regimen)Other lymphoproliferative disorders (selected)

Dosing

Adult: Hairy cell leukaemia: 0.09 mg/kg/day continuous IV infusion for 7 days (one course). MS (oral): 3.5 mg/kg total over 2 years (two annual courses of 2 treatment weeks).
Pediatric: Specialist (leukaemia protocols).
Renal adjustment: Reduce dose in renal impairment (MS: not recommended if CrCl <30).
Hepatic adjustment: Caution; MS tablet not recommended in moderate–severe impairment.
Geriatric: Assess organ function; infection risk.
Max dose: HCL: 0.09 mg/kg/day ×7 days/course; MS: 3.5 mg/kg cumulative over 2 y

Pharmacokinetics

Onset

Lymphocyte depletion over days–weeks

Peak effect

End of infusion (IV); ~0.5–1.5 h (oral Tmax)

Duration

Prolonged immunologic effect (months)

Half-life

~10 h (terminal; intracellular effect far longer)

Bioavailability

~40% (oral tablet)

Protein binding

~20%

Metabolism

Intracellular phosphorylation; limited hepatic

Excretion

Renal (substantial unchanged)

Contraindications

Pregnancy / inadequate contraception
Active malignancy (MS indication)
HIV infection (MS indication)
Active chronic infection (TB/hepatitis)
Hypersensitivity

Side effects

Common

LymphopeniaFever/infectionNauseaHeadacheFatigueRash

Serious

Prolonged severe lymphopenia/immunosuppression
Serious/opportunistic infections (incl. PML reported)
Myelosuppression
Secondary malignancy
Hepatotoxicity

Pregnancy & lactation

Pregnancy

Contraindicated — fetal harm; contraception during and 6 months after.

Lactation

Contraindicated during and ~1 week after dosing.