In the U.S.—

• Antineoplastic

Abarelix ( a-ba-REL-iks) is a type of medicine called a gonadotropin-releasing hormone (GnRH) antagonist that lowers the male hormone testosterone in your blood. Testosterone makes most prostate cancers grow. Other ways to treat your prostate cancer are taking other hormone medicines to lower testosterone or surgery to remove your testicles. Abarelix is used when these other ways to treat prostate cancer cannot be used or are refused.

Abarelix is to be given only under the supervision of your doctor. It is to be injected into a muscle and is available in the following dosage form:

Parenteral
• Injection (U.S.)

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For abarelix, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to abarelix or any of its ingredients. Also tell your doctor if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Abarelix is not for use in women.

Children—Studies on this medicine have only been done in adult patients, and there is no specific information comparing the use of abarelix in children with other age groups. Abarelix is not for use in children.

Older adults—This medicine has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are using abarelix, it is especially important that your doctor and pharmacist know if you are taking any of the following:

• Antiarrhythmic medications (medicine for heart conditions), such as
• Amiodarone (e.g., Cordarone)
• Procainamide (e.g., Procan SR, Pronestyl)
• Quinidine (e.g., Quinidex)
• Sotalol (e.g., Betapace)— using these medicines at the same time as abarelix may cause your heart conditions to get worse

• QT prolongation (rare heart condition)—May be worsened by abarelix

It is very important that you read the Patient Information for abarelix before you start getting injections. You will need to sign the last page if you agree with treatment with abarelix. If you have any questions about this ask your doctor.

Abarelix is only prescribed by doctors who are part of Plenaxis PLUS Program (Plenaxis User Safety Program) that is run by the pharmaceutical (drug) company that makes the medicine.

Abarelix is given as an injection (shot) in your buttocks. Your doctor or nurse will give you the injection. It is important that you keep your appointment with your doctor's office when your injection is due.

You must always wait in your doctor's office for at least 30 minutes after getting each abarelix injection (shot). If a serious or life-threatening allergic reaction happens it is usually soon after getting an abarelix injection. Tell your doctor right away if you feel warm, faint or lightheaded or if you have chest tightness, shortness of breath, redness of your skin, or swelling of your face, eyelids, tongue, or throat. These could be signs of an allergic reaction.

Abarelix is only used for treating advanced symptomatic prostate cancer when a patient cannot have or refuses other treatments for prostate cancer

Dosing—

The dose of abarelix will be different for different patients. The following information includes only the average doses of abarelix.

• For parenteral dosage form (injection):
  • For prostate cancer:
    • Adults—100 milligrams (mg) in the muscle (buttock) on Day 1, 15 29 (week 4) and every 4 weeks thereafter.

It is very important that your doctor check you at regular visits. Your doctor will also want to do regular blood tests about every 8 weeks to check your testosterone level to see if abarelix is working for you. If you weigh more than 225 pounds there may be a greater chance that abarelix may stop working. Your doctor may also want to do blood tests to check your liver function before and during treatment with abarelix.

This medicine may cause loss in bone mineral density with extended treatment. Loss in bone mineral density can lead to the thinning of bones (osteoporosis). If you have any questions about this ask your doctor.

This medicine can cause a change in heart rhythm called prolongation of the QTc interval. This condition may change the way your heart beats and can cause fainting and serious side effects in some patients. Contact your doctor right away if you have any of these symptoms or any questions about this.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• Less common
  • Fainting or loss of consciousness;  fast or irregular breathing;  itching;  skin rash;  swelling of eyes or eyelids ;  tightness in chest and/or wheezing;  trouble in breathing 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome.

• More Common
  • Back pain;  bladder pain;  breast enlargement;  breast pain;  bloating or swelling of face, arms, hands, lower legs, or feet ;  bloody or cloudy urine;  body aches or pain;  burning while urinating;  chills;  cough;  decrease in frequency of urination;  decrease in urine volume;  diarrhea;  difficult, burning, or painful urination;  difficulty having a bowel movement (stool);  difficulty in passing urine [dribbling];  dizziness;  ear congestion;  feeling of warmth;  fever;  frequent urge to urinate;  headache;  loss of voice;  lower back or side pain;  nasal congestion;  nausea;  pain;  rapid weight gain;  nipple enlargement;  redness of the face, neck, arms and occasionally upper chest ;  runny nose;  sneezing;  sore throat;  sweating;  tingling of hands or feet;  trouble in holding or releasing urine;  trouble in sleeping;  unusual tiredness or weakness;  unusual weight gain or loss 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.