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Generic Name: clofarabine (kloe FAR a been)
Brand Names: Clolar

What is Clolar?

Clolar (clofarabine) is a cancer medicine that interferes with the growth and spread of cancer cells in the body.

Clolar is used to treat acute lymphoblastic leukemia (a type of blood cancer) in children and young adults up to 21 years old.

Clolar is usually given after other cancer medicines have been tried without successful treatment.

Important information

Clolar can cause life-threatening side effects including: serious infection, severe skin rash, internal bleeding, and liver or kidney damage.

Call your doctor right away if you have: fever, chills, unusual bleeding or bruising, urination problems, stomach pain or swelling, loss of appetite, bloody diarrhea, coughing up blood, sudden numbness or severe headache, problems with vision or balance, or sudden swelling in your arms, legs and other parts of the body.

Clolar can harm your liver or kidneys. Call your doctor if you have lower back pain, little or no urinating, or blood in your urine.

Before taking this medicine

To make sure Clolar is safe for you, tell your doctor if you have:

  • any type of infection;

  • liver disease; or

  • kidney disease.

Using Clolar during pregnancy could harm the unborn baby. Tell your doctor if you are pregnant or if you become pregnant while using this medicine.

Use birth control to prevent pregnancy while you are receiving Clolar, whether you are a man or a woman. Clolar use by either parent may cause birth defects.

It is not known whether clofarabine passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are receiving Clolar.

How is Clolar given?

Clolar is injected into a vein through an IV. A healthcare provider will give you this injection.

Clolar is usually given daily for 5 days in a row during one or more 1-month treatment cycles. Your doctor will determine how many treatment cycles you will receive and how often.

You may receive other medications to help prevent certain side effects of Clolar.

Clolar can lower blood cells that help your body fight infections and help your blood to clot. Your blood will need to be tested often. Your kidney or liver function may also need to be tested. Your cancer treatments may be delayed based on the results of these tests.

Clolar dosing information

Usual Adult Dose for Acute Lymphoblastic Leukemia:

Less than 22 years:
Initial Dose: 52 mg/m2 by intravenous infusion over 2 hours daily for 5 consecutive days

Treatment cycles are repeated following recovery or return to baseline organ function, approximately every 2 to 6 weeks. Subsequent cycles should begin no sooner than 14 days from day 1 of the previous cycle. Subsequent cycles may be administered when the ANC is greater than or equal to 750/mm3.

Greater than 22 years:
Not approved for use by the FDA.

Usual Pediatric Dose for Acute Lymphoblastic Leukemia:

Less than 1 year:
Not approved for use by the FDA.

Greater than 1 year:
Initial Dose: 52 mg/m2 by intravenous infusion over 2 hours daily for 5 consecutive days

Treatment cycles are repeated following recovery or return to baseline organ function, approximately every 2 to 6 weeks. Subsequent cycles should begin no sooner than 14 days from day 1 of the previous cycle. Subsequent cycles may be administered when the ANC is greater than or equal to 750/mm3.

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Clolar injection.

What happens if I overdose?

Since Clolar is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

What should I avoid while receiving Clolar?

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Clofarabine can pass into body fluids (urine, feces, vomit). For at least 48 hours after you receive a dose, avoid allowing your body fluids to come into contact with your hands or other surfaces. Caregivers should wear rubber gloves while cleaning up a patient's body fluids, handling contaminated trash or laundry or changing diapers. Wash hands before and after removing gloves. Wash soiled clothing and linens separately from other laundry.

Clolar side effects

Get emergency medical help if you have signs of an allergic reaction to Clolar: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

A rare but serious side effect of Clolar is called capillary leak syndrome. Call your doctor right away if you have signs of this condition, which may include: stuffy or runny nose followed by weakness or tired feeling, and sudden swelling in your arms, legs and other parts of the body.

Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody;

  • a light-headed feeling, like you might pass out;

  • pain, redness, numbness, and peeling skin on the palms of your hands or the soles of your feet;

  • signs of infection - fever, chills, cold or flu symptoms, unusual weakness, mouth and throat ulcers, swollen gums, pain when swallowing, pale skin, easy bruising or bleeding (nosebleeds, bleeding gums), skin sores, rapid and shallow breathing, fainting;

  • signs of bleeding inside the body - sudden severe headache, chest pain, coughing up blood or vomit that looks like coffee grounds, rectal bleeding, bloody or tarry stools, sudden numbness or weakness (especially on one side of the body), problems with vision or speech;

  • signs of a liver problem - upper stomach pain, sudden swelling in your mid-section, jaundice (yellowing of the skin or eyes);

  • kidney problems - little or no urination, red or pink urine, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath;

  • severe skin reaction - fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling; or

  • signs of tumor cell breakdown - lower back pain, blood in your urine, little or no urinating; numbness or tingly feeling around your mouth; muscle weakness or tightness; fast or slow heart rate, weak pulse, feeling short of breath; confusion.

Common Clolar side effects may include:

  • fever, chills, flu symptoms, or other signs of infection;

  • stomach pain, nausea, vomiting, loss of appetite, diarrhea;

  • fast heartbeats;

  • nosebleeds, bruising;

  • pain in your arms or legs;

  • headache, feeling tired or anxious;

  • mild itching or skin rash; or

  • flushing (warmth, redness, or tingly feeling).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Clolar?

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Clolar, especially blood pressure medication.

Clolar can harm your liver or kidneys. This effect is increased when you also use other medicines harmful to the liver or kidneys. During your 5-day treatment with Clolar, you may need to avoid using certain medications. Many other drugs (including some over-the-counter medicines) can be harmful to the liver or kidneys, such as:

  • leflunomide, methotrexate, teriflunomide;

  • an antibiotic, antifungal medicine, antiviral medicine, sulfa drug, or tuberculosis medicine;

  • birth control pills or hormone replacement therapy;

  • gout or arthritis medications (including gold injections);

  • HIV/AIDS medications;

  • injectable osteoporosis medicine;

  • medication to prevent organ transplant rejection;

  • medicines to treat a bowel disorder;

  • medicines to treat mental illness;

  • other cancer medications;

  • cholesterol-lowering medications - Crestor, Lipitor, Pravachol, Simcor, Vytorin, Zocor, and others;

  • pain or arthritis medicines - acetaminophen (Tylenol), ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others; or

  • seizure medication - carbamazepine, phenytoin, and others.

This list is not complete. Other drugs may interact with clofarabine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about Clolar.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Clolar only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2018 Cerner Multum, Inc. Version: 6.01.

Date modified: March 02, 2017
Last reviewed: January 30, 2017