Understanding Ph+ CML in Chronic Phase

Ph+ CML in chronic phase

Even if you've been living with Ph+ CML for a while, it's still helpful to understand the biology behind the disease and what's happening in your body.

What causes Ph+ CML?

Ph+ CML is caused by an abnormal fusion gene called BCR-ABL1. It is the result of pieces of 2 chromosomes in the body trading places.

Here’s a brief overview:

  • Each cell in the human body has 23 pairs of chromosomes
  • In Ph+ CML, pieces from chromosomes 9 and 22 break off and swap places
  • This can create a new abnormal chromosome known as the Philadelphia (Ph) chromosome
  • The Ph chromosome creates the abnormal BCR-ABL1 fusion gene
  • This abnormal gene then produces an abnormal protein called BCR-ABL

How does Ph+ CML affect the body?

Ph+ CML affects your bone marrow and your blood. Your bone marrow is a sponge-like tissue in the center of most of your bones.

Here’s what happens in the bone marrow:

  • The BCR-ABL protein sends a signal to the bone marrow
  • The bone marrow starts creating too many immature white blood cells (commonly referred to as blast cells)
  • These cells, which your doctor may call leukemic cells, grow abnormally and do not become healthy white blood cells
  • The leukemic cells start to grow and divide and build up, crowding out red blood cells and platelets in the bone marrow

Here’s what happens in the bloodstream:

  • As the bone marrow becomes overcrowded with leukemic cells, these cells move into the bloodstream
  • Over time, the leukemic cells crowd out healthy red blood cells, white blood cells, and platelets
  • This can lead to serious health problems, including, but not limited to, a greater risk of infections, as well as anemia, bruising easily, and bleeding that takes longer to stop 

Doctors categorize the disease in phases instead of stages

While many types of cancer are categorized into stages, doctors assign 1 of 3 phases to Ph+ CML:

  • Chronic phase: The first phase of Ph+ CML, when the number of white blood cells is higher than normal. Most adults are diagnosed in chronic phase
  • Accelerated phase: The second phase of Ph+ CML, in which the number of immature white blood cells in the blood and bone marrow may increase rapidly
  • Blast phase: The third and final phase of Ph+ CML. This phase has the highest number of immature blood cells in the blood and bone marrow

Learn about SCEMBLIX as a treatment option

By being your own advocate, you can work closely with your doctor to determine whether SCEMBLIX® (asciminib) tablets is right for you.

SCEMBLIX is a prescription medicine used to treat adults with:

  • Philadelphia chromosome–positive chronic myeloid leukemia (Ph+ CML) in chronic phase (CP), previously treated with two or more tyrosine kinase inhibitors (TKIs). Learn More
    • The effectiveness of SCEMBLIX in patients previously treated with 2 or more TKIs is based on a study that measured major molecular response (MMR) rates. No clinical information is available to show if these patients treated with SCEMBLIX live longer or if their symptoms improve. Ongoing studies exist to find out how SCEMBLIX works over a longer period of time.
  • Ph+ CML in CP with the T315I mutation. Learn More

It is not known if SCEMBLIX is safe and effective in children.