Induction treatments for acute myeloid leukemia

Induction is the first phase of treatment given for newly diagnosed acute myeloid leukemia (AML). Induction treatment is also called remission induction therapy. The goal of induction treatment for AML is to clear the blood and bone marrow of leukemia cells (blast cells, or blasts) and bring about a complete remission, or complete response.

This treatment is usually given over one week, but you may be in the hospital for up to 5 weeks waiting for side effects to lessen or go away and for the bone marrow to return to normal function.

Bone marrow samples are taken 2 to 4 weeks after starting induction chemotherapy to see how well the treatment is working. If no leukemia cells are found in the bone marrow, no further treatment will be given for 2 to 4 weeks. Once blood counts are normal, the same marrow tests will be repeated and the doctor will check to see if the leukemia is in remission. Many people get complete remission after one round of induction. If there are still leukemia cells in the bone marrow, more induction therapy (called re-induction) will be given.

Your healthcare team will suggest induction treatments based on your needs and work with you to develop a treatment plan. Induction treatment usually involves chemotherapy and targeted therapy.

Chemotherapy uses anticancer drugs to destroy cancer cells. Chemotherapy is the main treatment used during the induction phase of AML treatment.

Most induction treatments are built around the chemotherapy drug cytarabine (Cytosar). This drug may be combined with other chemotherapy or targeted therapy drugs. Cytarabine and anthracyclines (a type of chemotherapy drug that interferes with DNA in cancer cells, including daunorubicin, idarubicin or mitoxantrone) are usually given in the 7-and-3 protocol. Cytarabine is given continuously for 7 days and then the anthracycline is given daily for 3 days. You will also receive targeted therapy if there are certain genetic mutations.

You may also be given hydroxyurea (Hydrea, Apo-hydroxyurea, Mylan-hydroxyurea) to help lower white blood cell (WBC) counts.

Induction treatment can be divided into categories. Intensive induction is generally used for those under the age of 70. Less intensive induction treatment is used for those over 70, and it often involves low-dose chemotherapy or targeted therapy or both. Some drugs that may be used include:

• hypomethylating agents such as azacitidine (Vidaza) or decitabine (Dacogen, Demylocan, Inqovi)
• low-dose cytarabine
• low-dose cytarabine and venetoclax (Venclexta) or glasdegib (Daurismo)
• hypomethylating agent (azacitidine or decitabine) and venetoclax

If you need a second course of induction treatment to get a complete remission, doctors may use the same or similar drugs given in the first course if there are fewer leukemia cells in the bone marrow than before treatment started. Doctors may use a different chemotherapy combination if there are still a large number of leukemia cells in the bone marrow after the first course of chemotherapy.

Find out more about chemotherapy for AML.

Targeted therapy uses drugs to target specific molecules (such as proteins) on cancer cells or inside them to stop the growth and spread of cancer.

Targeted therapy may be used as part of induction treatment.

• If you have AML with a mutation in the FLT3 gene, you may have targeted therapy drugs such as midostaurin (Rydapt).
• If you have AML with a CD33 protein marker, you may have targeted therapy drugs such as gemtuzumab ozogamicin.

Find out more about targeted therapy for AML.

The central nervous system (CNS) is the brain and spinal cord. If the leukemia has spread to the CNS, treatment may include chemotherapy given directly into the spinal fluid (called intrathecal chemotherapy). The drug used in intrathecal chemotherapy is methotrexate or cytarabine. It is usually given during a lumbar puncture. Find out more about chemotherapy for AML.

Radiation therapy uses high-energy rays or particles to destroy cancer cells. It is sometimes given to the brain and spinal cord along with intrathecal chemotherapy. Find out more about radiation therapy for AML.

Supportive therapy is important during every phase of treatment for AML. It is used to treat the complications that usually happen with treatments for AML and the disease itself.

Supportive therapies given during induction treatment may include:

• antibiotics, antivirals or antifungals to prevent or fight infections
• growth factors to help the bone marrow recover from chemotherapy (chemotherapy can affect the bone marrow so it doesn’t make enough healthy blood cells, which can increase the risk for infection)
• transfusions of red blood cells, platelets, fresh frozen plasma and cryoprecipitate (a product that replaces clotting factors)
• drugs to bring down high levels of some chemicals in the blood that increase when many cancer cells die at the beginning of treatment (called tumour lysis syndrome)
• leukapheresis to remove large numbers of white blood cells from the blood

Find out more about supportive therapy.

Talk to your doctor about clinical trials open to people with AML in Canada. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.