A trial of ponatinib for chronic myeloid leukaemia or Philadelphia positive acute lymphoblastic leukaemia (PACE)

This trial looked at a drug called ponatinib for chronic myeloid leukaemia (CML) or some types of acute lymphoblastic leukaemia (ALL). It is for people whose leukaemia had not responded to, or had got worse while having, other treatments.

Most people with CML, and some people with ALL, have a change (mutation) to a gene in their leukaemia cells. Doctors call this Philadelphia chromosome positive. It affects a protein called BCR-ABL1 which tells the body to make too many white blood cells.

Certain drugs called tyrosine kinase inhibitors (TKIs) can block the BCR-ABL1 protein. But sometimes these drugs don’t work very well, or they stop working (the leukaemia becomes resistant to them).

In this trial, researchers looked at a new TKI drug called ponatinib. The people taking part have already had other TKIs such as imatinib, nilotinib (Tasigna), dasatinib (Sprycel), or bosutinib but their leukaemia was not responding. Some people taking part had a genetic change in their leukaemia cells, called T315I, which makes them resistant to all other TKIs. The aim of this trial was to see if ponatinib helped people with CML or Philadelphia positive ALL who are in one of the following situations

• Their leukaemia was resistant to other TKI drugs

• They could not take other TKI drugs because of bad side effects

• They had the T315I gene change in their leukaemia cells