How does it work?
Vidaza injection contains the active ingredient azacitidine, which is a type of chemotherapy medicine used to treat cancer known as a cytotoxic antimetabolite. It is used to treat certain blood disorders in which the bone marrow produces abnormal blood cells.
The bone marrow produces cells called stem cells. These normally develop into the different types of blood cells (white blood cells, red blood cells and platelets) and when these are mature they leave the bone marrow and enter the bloodstream.
In leukaemia the bone marrow produces too many immature white blood cells. These abnormal cells take up space in the bone marrow and result in less room for production of normal healthy blood cells.
In another group of disorders that affect the bone marrow and blood cells, called myelodysplastic syndromes (MDS), the bone marrow doesn’t produce enough normal healthy blood cells. It may also produce too many immature blood cells.
Azacitidine treats these disorders by stopping the abnormal blood cells from multiplying. It does this by inhibiting the production of the cells' genetic material, DNA and RNA. Both DNA and RNA are needed for growth and multiplication of cells. Azacitidine causes a deficiency of DNA and RNA in the abnormal cells, and this causes the cells to grow in an unbalanced way, resulting in the death of the cells.
Unfortunately, azacitidine can also affect normal, healthy cells, particularly those that multiply quickly, such as blood cells and hair cells. The most important side effect is on the bone marrow where blood cells are made. Azacitidine can also temporarily decrease the production of healthy blood cells, leaving people susceptible to infection. Regular blood tests are therefore needed to monitor the levels of blood cells.
In most chemotherapy regimens, doses are administered in courses at various intervals to allow normal cells to recover from the adverse effects of the anticancer medicines between doses. However, during this period, cancer cells will also recover and start to replicate again. Successful treatment depends on the administration of the next course of therapy before the cancer cells reach their previous numbers and the net effect is to decrease the amount of cancer with each successive course.
What is it used for?
Vidaza is used to treat the following conditions in adults for whom treatment with stem cell transplantation is not suitable:
- Chronic myelomonocytic leukaemia (CMML).
- Acute myeloid leukaemia (AML).
- A group of disorders that affect the bone marrow and blood cells called myelodysplastic syndromes (intermediate-2 or high-risk).
How is this treatment given?
- Vidaza injection is given by an injection under the skin (subcutaneously) by a doctor or nurse. It may be given under the skin on your thigh, tummy or upper arm.
- Treatment with Vidaza is given in several cycles of treatment.
- Each cycle involves having one Vidaza injection administered daily for seven days, followed by a 21 day rest period.
- This treatment cycle is usually repeated every four weeks, depending on results of blood tests, usually for at least six treatment cycles.
- This medicine can decrease the number of healthy blood cells in your blood. A low white blood cell count can increase your susceptibility to infections; a low red blood cell count causes anaemia and a low platelet count can cause problems with blood clotting. For this reason, you will need regular blood tests to monitor your blood cells during treatment with this medicine. Tell your doctor immediately if you experience any of the following symptoms during your treatment, as they may indicate problems with your blood cells: unexplained bruising or bleeding, purple spots, black or tarry stools, sore mouth or throat, mouth ulcers, high temperature (fever) or other signs of infection, or suddenly feeling tired, breathless, or generally unwell.
- This medicine can sometimes cause problems with your kidneys. It is important to tell your doctor straight away if you notice that you are passing urine less often than usual, or if you notice any blood in your urine during your treatment.
- This medicine may be harmful to an unborn baby, and for this reason you should use effective contraception to avoid getting pregnant or fathering a child during treatment. You should continue to use contraception to prevent pregnancy for at least three months after treatment with this medicine is stopped, but discuss this with your doctor. Women should consult their doctor immediately if they get pregnant during treatment.
- Your ability to become pregnant or father a child may be affected by this medicine. It is important to discuss fertility with your doctor before starting treatment.
Use with caution in
- Decreased liver function.
- Decreased kidney function.
- People with low numbers of white blood cells in their blood (leucopenia or neutropenia).
- People with low numbers of platelets in their blood (thrombocytopenia).
- People with heart or lung disease, as the manufacturer has not studied the medicine in people with these problems.
Not to be used in
- Advanced liver cancer.
- This medicine is not recommended for children or adolescents under 18 years old, as its safety and effectiveness have not been established in this age group.
This medicine should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- This medicine should not be used in pregnancy, unless considered essential by your doctor due to life-threatening disease, because it may be harmful to a developing baby.
- Women who could get pregnant should use effective contraception to prevent pregnancy, and men should use effective contraception to prevent fathering a child, both during treatment, and for at least three months after treatment is finished. Seek further medical advice from your doctor.
- It is not known if this medicine passes into breast milk. Mothers who need treatment with this medicine should not breastfeed. Seek medical advice from your doctor.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.
Very common (affect more than 1 in 10 people)
- Decrease in the number of healthy white blood cells, red blood cells or platelets in the blood (leukopenia and neutropenia, anaemia and thrombocytopenia) – see warning section above.
- Fever (high temperature).
- Disturbances of the gut such as diarrhoea, vomiting, constipation, nausea, abdominal pain.
- Chest pain.
- Pain in the joints.
- Reaction at site of injection such as redness and pain.
- Skin reactions such as itching and rash.
- Red dots on the skin or bruising due to bleeding under the skin.
- Loss of appetite.
- Shortness of breath.
Common (affect between 1 in 10 and 1 in 100 people)
- Difficulty sleeping (insomnia).
- Feeling confused.
- Infections – including chest infections, urine tract infections and blood infections (sepsis).
- Blocked or runny nose or sinuses.
- Low potassium levels in the blood.
- Feeling weak or generally unwell.
- Changes in blood pressure.
- Sore mouth including sore and bleeding gums, inflammation of the lining of the mouth, cold sores.
- Hair loss.
- Pain in the throat.
- Muscle pain.
- Bleeding, for example from the gums or from piles, or in the gut, eye, skin or brain. Tell your doctor straight away if you notice any new or unusual bleeding, including blood in your urine, during your treatment.
- Kidney failure.
- Weight loss.
- Bruising, hardening, itching, inflammation, rash or discolouration of skin at the injection site.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- Liver failure.
- Allergic reactions.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while being treated with this one, to make sure that the combination is safe.
There may be an increased risk of side effects if this medicine is used in combination with other medicines which can also suppress bone marrow function and affect blood cell counts, for example other chemotherapy medicines, or the antipsychotic clozapine.
Vaccines may be less effective in people receiving chemotherapy. This is because chemotherapy medicines reduce the activity of the immune system and can prevent the body forming adequate antibodies. Live vaccines should be postponed until at least six months after finishing chemotherapy because they may cause infection. Live vaccines include the following: oral polio; rubella; measles, mumps and rubella (MMR); BCG; chickenpox; yellow fever and oral typhoid vaccines.
Other medicines containing the same active ingredient
There are currently no other medicines available in the UK that contain azacitidine as the active ingredient.