![[logo] HealthTree Foundation](https://static.healthtree.org/icons/icon_spinner.svg){kind=icon}
![[logo] HealthTree Foundation](https://static.healthtree.org/logo_icon_only.svg){kind=icon}
How it is administered
Cladribine is most commonly given as an intravenous (IV) infusion. For blood cancers, such as Hairy Cell Leukemia (which is similar in some ways to B-cell Prolymphocytic Leukemia), the standard dose is 0.09 mg/kg/day, administered continuously over 24 hours for 7 consecutive days. The medication comes in single-use vials and must be diluted with a specific solution before being infused. It is not mixed with other drugs in the same IV line.
There is also an oral tablet form of cladribine, but this is primarily used for multiple sclerosis and not for blood cancers.
How it works
Cladribine is a type of chemotherapy known as a purine nucleoside analog. It works by interfering with the DNA synthesis and repair processes in certain types of white blood cells, especially lymphocytes and monocytes. Cladribine enters these cells and is converted into an active form that accumulates inside the cell. This buildup damages the cell’s DNA, preventing it from dividing and leading to cell death.
What makes cladribine unique is that it can kill both actively dividing and resting (quiescent) lymphocytes. This broad action helps reduce the number of abnormal white blood cells in blood cancers. The medication is particularly effective in cells with high levels of an enzyme called deoxycytidine kinase, which is common in many blood cancers. By targeting these cells, cladribine helps restore normal blood cell levels and improve symptoms.
Common side effects
- Fatigue (31%)
- Fever (33%)
- Nausea (22%)
- Rash (16%)
- Headache (14%)
- Vomiting (9%)
- Decreased appetite (8%)
- Diarrhea (7%)
- Cough (7%)
- Myalgia (muscle pain, 6%)
- Dizziness (6%)
- Pain (6%)
- Asthenia (weakness, 6%)
- Insomnia (3%)
- Chills (2%)
- Edema (swelling, 2%)
- Administration site reactions (11%)
Blood-related side effects include:
- Neutropenia (low white blood cell count)
- Anemia (low red blood cell count)
- Thrombocytopenia (low platelet count)
Serious infections, including pneumonia and sepsis, have been reported, especially in the first month after treatment.
Who Should take it
Cladribine is FDA-approved for the treatment of active Hairy Cell Leukemia, a rare type of blood cancer. It is used when patients have symptoms such as anemia, low white blood cell counts (neutropenia), low platelet counts (thrombocytopenia), or other disease-related problems.
While cladribine is not specifically approved for B-cell Prolymphocytic Leukemia, it may be considered in certain cases of blood cancers where similar types of abnormal lymphocytes are present, especially if other treatments have not worked. The decision to use cladribine should be made by a hematologist or oncologist familiar with blood cancers.
Who should not take it
Cladribine should not be used in patients who are allergic to cladribine or any of its components. It is also not recommended for people with active infections, as it can further suppress the immune system and increase the risk of serious infections.
Pregnant women should not take cladribine, as it can cause harm to the unborn baby. Women of childbearing age should use effective contraception during treatment. Caution is also advised in patients with significant kidney or liver problems, as the safety of cladribine in these situations has not been fully studied.
Commonly used with
Cladribine is often used as a single agent (monotherapy) for blood cancers like Hairy Cell Leukemia. It is not typically combined with other chemotherapy drugs during the same treatment course due to the risk of increased side effects, especially bone marrow suppression.
Supportive medications, such as antibiotics, antifungals, or antivirals, may be given to help prevent or treat infections during periods of low white blood cell counts.
Commonly tested with
Cladribine has been studied in combination with other chemotherapy agents, especially in clinical trials for blood cancers. In high-risk or relapsed cases, it has been tested with drugs like cyclophosphamide and as part of bone marrow transplant conditioning regimens. However, these combinations are not standard for most patients due to increased risk of toxicity.
Cladribine may also be tested alongside supportive care medications, such as growth factors or transfusions, to manage side effects.
HealthTree Foundation is a qualified 501(c)(3) tax-exempt organization.
Copyright © 2025 HealthTree Foundation. All rights reserved.
Tax ID 45-5354811