How does this medication work? What will it do for me?

Clofarabine belongs to the group of cancer-fighting medications known as antineoplastics. It is used to treat pediatric patients (1 to 21 years old) with acute lymphoblastic leukemia (ALL) that has either been previously treated and has now returned, or is not responding to other medications. Clofarabine causes the death of cancer cells by interfering with the genetic material DNA, which is necessary for reproduction and growth of cells.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Each mL of sterile solution for injection contains 1 mg clofarabine. Nonmedicinal ingredients: sodium chloride and water for injection.

How should I use this medication?

The usual dose of this medication is based on body size. The doctor will calculate the dose based on body surface area, which takes into account a person's height and weight.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Clofarabine is usually injected into a vein through a site on your skin that has been specially prepared for this purpose. Very careful handling of this medication is required. It is always given under the direct supervision of a doctor in a hospital or similar setting with access to sterile equipment for preparation.

This medication is usually given over 2 hours daily for 5 consecutive days, followed by a recovery period of 2 to 6 weeks, before being repeated.

It is important this medication be given exactly as recommended by your doctor. If you miss an appointment to receive clofarabine, contact your doctor as soon as possible to reschedule your appointment.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take clofarabine if you or your child:

  • are allergic to clofarabine or any ingredients of the medication
  • have leukemia cells in the fluid that surrounds the brain and spinal cord
  • have a history of serious liver disease
  • have a history of serious kidney disease
  • have or have had serious heart disease
  • have or have had serious disease of the pancreas
  • have severely reduced liver or kidney function

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • anxiety
  • constipation
  • cough
  • diarrhea
  • fatigue
  • flushing
  • headache
  • loss of appetite
  • mouth sores, sore throat
  • muscle aches
  • nausea
  • pain, redness or blistering of hands and feet
  • sleepiness
  • vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • back pain
  • bone pain
  • changes in blood pressure
  • diarrhea, nausea, vomiting lasting more than 24 hours
  • feeling of being unwell
  • muscle and joint pain
  • rapid heart beat
  • shortness of breath
  • signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
  • signs of bleeding (e.g., bloody nose, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
  • signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)

Seek immediate medical attention if any of the following occur:

  • signs of dehydration (e.g., fainting spells, dizziness, lightheadedness, decreased urination)
  • signs of fluid gathering around the heart (e.g., chest pain, shortness of breath when lying down, painful breathing, fainting, dizziness)
  • signs of infection (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
  • signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
  • signs of severe bleeding (e.g., vomit resembling coffee grounds in texture and color, black tarry stools)
  • signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
  • symptoms of tumour lysis syndrome (e.g., rapid breathing, heartbeat, decreased urine output, dizziness or lightheadedness)
  • symptoms of systemic inflammatory response syndrome (e.g., rapid heartbeat, rapid breathing, difficulty breathing, very high or very low body temperature and low blood pressure)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Anemia: Clofarabine may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired or pale skin, contact your doctor as soon as possible.

Your doctor will do blood tests regularly to monitor the number of specific types of blood cells, including red blood cells, in your blood.

Bleeding: Clofarabine may cause a reduced number of platelets in the blood, which can make it difficult to stop cuts from bleeding. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.

Dehydration: Clofarabine may cause vomiting and diarrhea, just like other cancer medications. In some circumstances, dehydration may develop. Check with your doctor if you experience decreased urine production, fainting spells, lightheadedness or severe dizziness.

Infection: As well as killing cancer cells, clofarabine can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people with contagious infections and areas with lots of people.  Tell your doctor immediately if you notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of specific types of blood cells in your blood.

Kidney function: If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

Clofarabine may reduce liver function and can cause liver failure. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Systemic Inflammatory Response Syndrome: This is a result of the body's natural defenses being over-stimulated, causing a release of cytokines, natural chemicals that work to protect the body. These chemicals cause inflammation throughout the body which can cause serious harm to the liver, kidney and other organs, and may be fatal if not treated quickly. Symptoms of this syndrome include rapid heartbeat, rapid breathing, difficulty breathing, very high or very low body temperature and low blood pressure. If you or your child experiences these symptoms, get immediate medical attention.

Tumour lysis syndrome: When large numbers of cancer cells are destroyed quickly, the body has difficulty getting rid of them. This can lead to a temporary, but possibly deadly set of symptoms referred to as tumour lysis syndrome. Your doctor will prescribe some medications to help your body manage this overload, however symptoms are still possible. If you experience or notice any of the following in your child, contact the doctor immediately. Symptoms of tumour lysis syndrome include: rapid breathing, rapid heartbeat, dizziness or lightheadedness, joint pain or decrease in urination.

Pregnancy: There is a possibility of birth defects if clofarabine is used during pregnancy. Effective birth control should be practiced while using this medication as this medication may harm the baby if used during pregnancy. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if clofarabine passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Adults and seniors: The safety and effectiveness of this medication have not been established for individuals over 21 years of age.

What other drugs could interact with this medication?

There may be an interaction between clofarabine and any of the following:

  • amphoteracin B
  • digoxin
  • clozapine
  • echinacea
  • leflunomide
  • natalizumab
  • pimecrolimus
  • tacrolimus (topical)
  • tofacitinib
  • trastuzumab
  • vaccines
  • warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.