Cladribine is a chemotherapy medicine. For cancer, it is most often given as an injection into a vein. There is also a tablet form (brand name Mavenclad) used to treat multiple sclerosis (MS), not cancer.
Brand Name(s)
- United States (tablets): Mavenclad (4 Tabs); Mavenclad (5 Tabs); Mavenclad (6 Tabs); Mavenclad (7 Tabs); Mavenclad (8 Tabs); Mavenclad (9 Tabs); Mavenclad (10 Tabs)
- Canada (tablets): Mavenclad
- Injection for cancer: usually given as generic cladribine.
Warning(s)
- Low blood counts: Cladribine can lower your bone marrow function. This raises the risk of infection, bleeding, and anemia. Watch for fever, chills, easy bruising, or unusual tiredness.
- Infections: You may get infections more easily, including shingles. Wash your hands often and avoid close contact with people who are sick. Tell your care team if you have signs of infection or mouth sores.
- Serious brain infection (PML): Rarely, a severe brain problem called PML can happen. Get help right away for confusion, memory problems, vision changes, trouble speaking, balance issues, or weakness on one side.
- Severe skin reactions: Stevens-Johnson syndrome/toxic epidermal necrolysis can occur. Seek care for painful rash, blistering or peeling skin, red or irritated eyes, or mouth sores.
- Bleeding risk: You may bleed more easily. Tell your team if you cough or vomit blood, have black or tarry stools, blood in urine, gum bleeding, or bruises that appear or grow.
- Kidney problems (cancer treatment): This drug can affect the kidneys, and the risk may be higher with other kidney-harming drugs. Report trouble passing urine, blood in urine, big weight gain, or swelling.
- Nerve problems: Serious nerve damage has happened, including long-lasting weakness or paralysis. Tell your doctor about burning, numbness, tingling, or weakness in your arms or legs.
- Tumor lysis syndrome (TLS): In some cancer patients, TLS can happen and can be life-threatening. Call your team for fast or abnormal heartbeat, fainting, muscle cramps or weakness, reduced urine, nausea, vomiting, diarrhea, or not eating.
- Liver and infection screening: Hepatitis (B or C) and tuberculosis have happened. You may be tested before treatment and at certain times later.
- Allergic reactions: Severe allergy can occur. Get emergency help for rash, hives, swelling of face or throat, wheezing, or trouble breathing.
- Vaccines: Some vaccines may not work as well or may raise infection risk while you are on this drug. Ask your care team before getting any vaccines.
- Transfusions: If you have ever received cladribine and you need a blood transfusion, make sure your care team knows.
- Pregnancy and breast-feeding: Cladribine may harm an unborn baby. Tell your doctor if you are pregnant or may become pregnant. Do not breast-feed while taking this drug, and ask how long to avoid breast-feeding after the last dose.
- For tablets used for MS (not cancer): Cladribine tablets may raise the risk of cancer and are not used for people who have cancer. Strict birth control is required during treatment and for a period after the last dose. Your doctor may order tests (such as hepatitis and TB screening, and sometimes MRI) before dosing.
Kind of Cancers It Is Used For (not a complete list)
- Hairy cell leukemia (HCL)
- Sometimes used for other rare blood cancers at a specialists direction
Your care team will decide if cladribine is appropriate for your specific cancer type.
Mechanism of Action
Cladribine is an antimetabolite (a purine nucleoside analog). After it enters cells, it is changed into an active form that builds up in certain white blood cells (lymphocytes). It blocks DNA building and repair, causing the cancer cells to stop dividing and die.
Because it strongly lowers certain immune cells, it can also raise infection risk.
Common Side Effects
- Feeling dizzy, tired, or weak
- Headache
- Muscle or joint pain
- Upset stomach, nausea, vomiting, diarrhea, or decreased appetite
- Irritation, pain, or redness where the injection goes in
- Cold-like symptoms
- Hair thinning or hair loss
Not everyone has these effects. Call your care team if side effects are severe, do not improve, or worry you.
Last reviewed: 2025-12-17
