Cladribine

What it is and how it works

Mechanism of Action The mechanism by which cladribine exerts its therapeutic effects in patients with multiple sclerosis has not been fully elucidated but is thought to involve cytotoxic effects on B and T lymphocytes through impairment of DNA synthesis, resulting in depletion of lymphocytes.

Indications

Cladribine tablets are indicated for the treatment of relapsing forms of multiple sclerosis (MS), to include relapsing-remitting disease and active secondary progressive disease in adults. Because of its safety profile, use of cladribine tablets is generally recommended for patients who have had an inadequate response to, or are unable to tolerate, an alternate drug indicated for the treatment of MS [ see Warnings and Precautions ]. Limitations of Use Cladribine tablets are not recommended for use in patients with clinically isolated syndrome (CIS) because of its safety profile [ see Warnings and Precautions ]. Cladribine tablets are purine antimetabolite indicated for the treatment of relapsing form of multiple sclerosis (MS), to include relapsing-remitting disease in adults. Because of its safety profile, use of cladribine tablets are generally recommended for patients who have had an inadequate response to, or are unable to tolerate, an alternate drug indicated for the treatment of MS.

Dosage and administration (summary)

Assessments are required prior to starting each cladribine treatment course. Cumulative dosage of 3.5 mg/kg administered orally and divided into 2 treatment courses (1.75 mg/kg per treatment course). Each treatment course is divided into 2 treatment cycles. Cladribine tablets are a cytotoxic drug. Separate administration from any other oral drug by at least 3 hours. Assessments Prior to Starting Each Cladribine Treatment Course Cancer Screening Follow standard cancer screening guidelines because of the risk of malignancies [ see Boxed Warning and Warnings and Precautions ].

Contraindications

Cladribine tablets are contraindicated: in patients with current malignancy [ see Warnings and Precautions ] . in pregnant women and in females and males of reproductive potential who do not plan to use effective contraception during cladribine tablets dosing and for 6 months after the last dose in each treatment course for females, and 14 weeks for males. May cause fetal harm [ see Warnings and Precautions and Use in Specific Populations (8.1, 8.3 )].

Warnings and precautions

Lymphopenia: Monitor lymphocyte counts before, during and after treatment. Infections: Serious, including life-threatening and fatal infections, have occurred. Screen patients for active and latent infections; delay treatment until infection is fully resolved or controlled. Vaccination of patients seronegative to varicella zoster virus (VZV) is recommended prior to treatment. Vaccination of patients seropositive to VZV with zoster vaccine recombinant, adjuvanted, is recommended prior to or during treatment.

Pregnancy

Pregnancy Risk Summary Cladribine tablets are contraindicated in pregnant women and in females and males of reproductive potential who do not plan to use effective contraception. There are no adequate data on the developmental risk associated with use of cladribine in pregnant women.

Storage and supply

How Supplied Cladribine tablets, 10 mg, are white to off white, round, biconvex tablets debossed with “10” on one side and plain on the other side. Each tablet is packaged in a child-resistant day pack containing one or two tablets in a blister card.

Source: Cladribine (Cladribine) — US FDA prescribing information, 2026-06-08, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.