Last reviewed 2026-04-22 · How we verify

Cladribine Tablets

Cladribine is a purine nucleoside analog that inhibits ribonucleotide reductase and gets incorporated into DNA, causing selective depletion of lymphocytes.

Cladribine is a purine nucleoside analog that inhibits ribonucleotide reductase and gets incorporated into DNA, causing selective depletion of lymphocytes. Used for Hairy cell leukemia, Multiple sclerosis (relapsing forms).

At a glance

Mechanism of action

Cladribine is a deoxyadenosine analog that is phosphorylated intracellularly and incorporated into DNA, leading to strand breaks and apoptosis. It preferentially affects lymphocytes due to their high deoxycytidine kinase activity and low 5'-nucleotidase activity, making it useful in hematologic malignancies and autoimmune conditions.

Approved indications

• Hairy cell leukemia
• Multiple sclerosis (relapsing forms)

Common side effects

• Myelosuppression (neutropenia, thrombocytopenia, anemia)
• Infection
• Nausea and vomiting
• Fever
• Fatigue

Key clinical trials

• Cladribine Tablets Level of Response Predictors in Clinical Practice (CLODINA)
• Oral Cladribine B-cell Study
• A Study of Suboptimally Controlled Participants Previously Taking Oral or Infusion DMDs for RMS (MASTER-2)
• Cladribine Tablets After Treatment With Natalizumab (CLADRINA) (PHASE4)
• Traditional Versus Early Aggressive Therapy for Multiple Sclerosis Trial (NA)
• ChariotMS - Cladribine to Halt Deterioration in People With Advanced Multiple Sclerosis (PHASE2, PHASE3)
• Prospective Effectiveness and Safety Study of Cladribine in Participants Who Change First-line DMD Treatments for Multiple Sclerosis (CLAD CROSS)
• Cladribine Tablets: Collaborative Study to Evaluate Impact On Central Nervous System Biomarkers in Multiple Sclerosis (PHASE4)

Primary sources

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