Bortezomib, commonly known as Velcade®, is currently used to treat people who have multiple myeloma. It can also be used to treat other types of cancer as part of a research trial.
WHAT IS BORTEZOMIB?
Bortezomib is a type of treatment called a proteaseome inhibitor. Proteasomes are a group of enzymes that are found in all of the body's cells. They play an important role in controlling cell function and growth.
HOW DOES BORTEZOMIB WORK?
Bortezomib interferes with the way proteasomes work, which may cause the cancer cells to die and may halt the cancer's growth. Cancer cells are more sensitive to the effects of bortezomib than normal cells.
WHEN IS BORTEZOMIB USED?
Bortezomib can be given alone to treat people who have already been treated with at least one other type of chemotherapy, and who have already had, or are unsuitable for, a bone-marrow transplant and whose myeloma has continued to grow.
It can also be given in combination with chemotherapy, as the first treatment for people with multiple myeloma who are not suited for high-dose chemotherapy with a bone-marrow transplant. It is usually given alongside the chemotherapy drug melphalan and the steroid prednisone.
WHAT DOES BORTEZOMIB LOOK LIKE?
Bortezomib is a transparent, colorless liquid.
HOW IS BORTEZOMIB ADMINISTERED?
Bortezomib is injected into a vein (intravenously) through a thin tube (cannula). It can be given through a central line that is inserted below the skin, passing through a vein located near the collarbone. Alternatively, it can be given through a PICC inserted in a vein in the arm. Bortezomib can also be administered as an injection below the skin (subcutaneously).
When administered on its own, bortezomib is normally given in four doses over a period of three weeks. The doses are given on days 1, 4, 8, and 11, followed by a 10-day rest period. This makes up one cycle of treatment. You can have up to eight cycles of treatment over six months.
When bortezomib is given in combination with melphalan and prednisone, it is given over nine cycles of six weeks. In the first four cycles, bortezomib is given twice weekly. During cycles 5 to 9, it is given once a week. Your doctor, nurse, or pharmacist will explain this to you.
POSSIBLE SIDE EFFECTS OF BORTEZOMIB
Each person reacts differently to a given drug. Some people have very few side effects, while others may develop more. The side effects described here will not affect everyone who is treated with bortezomib.
We outline the most commonly side effects, though we have left out the rarer ones. If you notice you develop any side effects that are not listed here, talk to your doctor or nurse.
NUMBNESS OR TINGLING IN THE HANDS OR FEET
This is caused by the effect of bortezomib on the nerves, and is known as peripheral neuropathy. You may also notice you have difficulty buttoning your clothing or performing complex tasks. Tell your doctor if you notice any changes. It is also important that you tell your doctor if you have pain in your hands or feet, as your dose of bortezomib can be lowered to avoid further problems.
If the symptoms are severe, bortezomib can be withdrawn for a time until your symptoms clear up, at which point your treatment can be resumed at a lower dose.
DIZZINESS WHEN STANDING UP
You may feel dizzy or light-headed if you get up quickly. This is caused by a temporary decrease in your blood pressure. Tell your doctor if you have dizziness or feel nauseous, as you may need additional treatment to help you with this. Drinking lots of fluids and moving about slowly can help.
Feeling tired is a common side effect of bortezomib. It is important that you try to pace yourself and rest as much as you need to. Try to get some light exercise, such as taking short walks. If you feel drowsy, don't drive or operate heavy machinery.
NAUSEA AND VOMITING
Your doctor can prescribe antiemetic drugs, which can prevent or substantially reduce your nausea and vomiting.
If your nausea remains uncontrolled or continues, tell your doctor, as they can prescribe other drugs that could work better. Some antiemetic drugs can cause constipation. Tell your doctor or nurse if this is a problem.
LOSS OF APPETITE
Some people lose their appetite while taking bortezomib. This can be mild and last for a few days. If it doesn't get better, request to see a dietitian or specialist nurse at your hospital. They can give you advice on how to improve your appetite and maintain a healthy weight.
CHANGES IN TASTE
You may notice that food tastes different. The normal taste of food comes back after the treatment has concluded. A dietitian or specialist nurse can give you advice on ways to cope with this side effect.
CONSTIPATION OR DIARRHEA
Bortezomib can cause constipation or diarrhea. Constipation can usually get better by drinking lots of fluids, eating a more fiber-rich diet, and getting some light exercise. If your constipation is severe or lasts for more than three days, tell your doctor, as you may require additional treatment.
Normally, this can be easily controlled with drugs, so tell your doctor if your diarrhea is severe or ongoing. It's important to drink lots of fluids if you have diarrhea.
HIGH TEMPERATURE AND CHILLS
This can happen a few hours after treatment with bortezomib, though it normally doesn't last much longer. Your doctor can prescribe medicines to lessen these effects.
Tell your doctor if you have headaches, as he or she can advise you on what could help you.
RISK OF INFECTION
Bortezomib can reduce your number of white blood cells, which help fight off infection. White blood cells are produced by bone marrow. If your white blood cell count is low, you will be more prone to infection. A low number of white blood cells is called neutropenia.
Contact your doctor or your hospital immediately if:
your temperature rises above 38 ° C
you suddenly feel unwell, even if your temperature is normal.
Bortezomib can increase the risk of developing shingles (herpes zoster virus). You may be given antiviral drugs to help prevent this infection.
BRUISING AND BLEEDING
Bortezomib can reduce the production of platelets, which help the blood to clot. Tell your doctor if you have any unexplained bleeding or bruising, such as nosebleeds, bleeding gums, blood spots, or skin rashes. You may have a platelet transfusion if your platelet count is low.
ANEMIA (LOW RED BLOOD CELLS)
Bortezomib can reduce the number of red blood cells, which transport oxygen throughout the body. A low number of red blood cells is called anemia. This may make you feel tired and short of breath. Tell your doctor or nurse if you have these symptoms. You may need a blood transfusion if the number of red blood cells in your blood is too low.
MUSCLE CRAMPS AND PAINFUL LIMBS
Tell your doctor if you have muscle cramps or painful limbs so that suitable painkillers can be prescribed.
Bortezomib can cause temporary breathlessness. Tell your doctor if you feel you are out of breath or notice changes in the way you breathe.
CHANGES IN THE EYES
Bortezomib can cause soreness in the eyes or blurriness of vision. Tell your doctor if you notice any changes in your vision.
In some people, bortezomib can cause depression, feelings of anxiety, or difficulty sleeping. Talk to your doctor if this happens to you.
It is important that you drink lots of fluids (2-3 liters per day) while taking bortezomib.
ADDITIONAL INFORMATION ON BORTEZOMIB
Bortezomib may affect your ability to drive. Do not drive if you feel dizzy, have blurry vision, or feel excessively tired.
Some drugs, including those bought over the counter in a store or pharmacy, may be harmful to you while you are taking bortezomib. Tell your doctor if you are taking any drugs, including over-the-counter medications, complementary therapies, and herbal medicines.
It is not advisable to become pregnant while taking bortezomib, as the drug can harm developing babies. It is important to use an effective method of contraception while you take this drug and for at least a couple of months afterward. You can talk about this with your doctor.
It is unknown whether bortezomib is present in semen or vaginal fluid. In order to protect your partner, it is safest to avoid having sex or use a barrier contraceptive device for about 48 hours after the chemotherapy.
This treatment may affect your ability to conceive or give birth. It is important that you talk to your doctor before beginning treatment.
There is a potential risk that bortezomib may be present in breast milk, and therefore women are recommended not to breast feed during the treatment and for a few months afterward.