The treatment of acute myeloid leukemia is quite challenging, with various considerations that need to be taken to tailor therapeutics and achieve the best results. In many cases, results can vary widely depending on age, the agents used and the overall health of the patients. Also, the risk of recurrence should be taken into account. Some chemotherapy regimens are associated with a higher risk of recurrence than others. Other drugs need the presence of a certain antigen or “marker” before their administration; the so-called “targeted therapy”. Finally, the treatment of acute promyelocytic leukemia, which is a subtype of acute myeloid leukemia, can vary from the usual regimens.
Treatment options for AML
The mainstay of treatment of acute myeloid leukemia is chemotherapy, it is used as an induction treatment for a few days, followed by consolidation treatment -that may or may not include chemotherapy- to reduce the risk of recurrence.
A) Induction therapy:
The most commonly used chemotherapy for induction is called the “3 and 7 regime”. It includes an intravenous infusion of anthracycline for 3 days in combination with 7 days of cytarabine. Cytarabine acts by preventing DNA from replicating, which is a key step in cell multiplication seen in cancers, while anthracyclines are a group of drugs that act on an enzyme called topoisomerase II which is a key enzyme in DNA replication through preventing the DNA from “winding around itself”. The most commonly used drug in the anthracycline family is daunorubicin. The main drawback of chemotherapy is that it is not suitable for frail patients and optimal body systems are needed to withstand their toxicity. Old and weak patients may have a higher risk of side effects, and all of these drugs are toxic to the bone marrow, especially because high doses may be needed in non-responders.
Other options for induction include targeted therapy as Midostaurin, which targets a certain mutation in cancer cells and acts against multiple enzymes. It proves beneficial when used with the standard chemotherapy during induction. Also, Cladribine is used as a catalyst for cytarabine since it increases the amount of cytarabine intake into cancer cells, increasing its efficacy.