When other cancer medications have failed, healthcare providers may recommend the use of Bosulif. This prescription chemotherapy drug is specifically used to treat a type of leukemia called chronic myelogenous leukemia, which is a slowly progressing cancer. Bosulif is approved only for adults age 18 and older. It works by slowing down the production of abnormal blood cells.
Bosulif® (bosutinib) is a prescription medication approved to treat a certain type of leukemia. It belongs to a group of medicines known as tyrosine kinase inhibitors.
Leukemia is a cancer that starts in the blood-forming tissue, such as the bone marrow, and causes large numbers of abnormal blood cells to be produced. Over time, the abnormal blood cells (also called leukemia cells) build up in the blood and bone marrow and crowd out normal, healthy white blood cells, red blood cells, and platelets. This can cause serious problems, such as infections, anemia, and bleeding.
There are four main types of leukemia, which are categorized based on how quickly the leukemia progresses and the type of blood cells affected. Chronic myelogenous leukemia (CML) is a slowly progressing type of leukemia that mainly affects older adults. In CML, the bone marrow makes too many of a type of white blood cell known as granulocytes (see Types of Leukemia for information about the other types). CML is sometimes called chronic myeloid leukemia or chronic granulocytic leukemia.
Most people with CML have an abnormal chromosome known as the Philadelphia chromosome (abbreviated Ph chromosome). Chromosomes are threadlike structures found in cells that contain DNA. The Philadelphia chromosome occurs when a piece of one chromosome breaks off and trades places with a piece that has broken off from another chromosome.
The Ph chromosome causes the bone marrow to make an enzyme known as tyrosine kinase. Tyrosine kinase, in turn, causes the production of large amounts of abnormal granulocytes. CML associated with the Ph chromosome is called Ph chromosome-positive CML.
CML generally progresses through three phases, or stages. These three stages include:
- Chronic phase
- Accelerated phase
- Blast phase.
Most people are diagnosed in the chronic phase. In this phase, symptoms are usually mild or not present. As the number of leukemia cells increases, the disease moves into the accelerated phase, and eventually the blast phase. In the blast phase, CML is much more aggressive, and symptoms may become significant.
(Click Phases of Chronic Myelogenous Leukemia for more information about the phases of CML.)
Bosulif is approved to treat adults with Ph chromosome-positive CML in the chronic, accelerated, or blast phase who are no longer responding to or cannot tolerate other leukemia medications. It was studied in people who had been previously treated with imatinib (Gleevec®) or imatinib followed by another tyrosine kinase inhibitor, namely dasatinib (Sprycel®) or nilotinib (Tasigna®).