In a nutshell
This study aimed to investigate the effectiveness and safety of ponatinib (Iclusig) for patients with chronic phase chronic myelogenous leukemia.
This study concluded that ponatinib is safe and effective in this group of patients.
Some background
The Philadelphia chromosome (BCR-ABL1) is found in almost all patients with chronic myeloid leukemia (CML). BCR-ABL1 is an oncogenic gene (cancer causing). Ponatinib is a targeted therapy, targeting BCR-ABL1. It is thought that it may be useful in patients with chronic phase CML (CP-CML).
It was unknown if ponatinib would be safe and effective for patients with CP-CML who had received prior treatment.
Methods & findings
This study involved 267 patients with Philadelphia chromosome positive CP-CML. Patients received 45mg once daily of ponatinib. Patients were then followed for an average of 56.8 months.
60% of patients achieved a major cytogenic response (MCyR). An MCyR is when the levels of Philadelphia chromosomes in blood and bone marrow decrease. 40% of patients achieved a major molecular response (MMR) while 24% achieved a molecular response (MR). MR measures the level of BCR-ABL1 gene in leukemia cells. In those that achieved MCyR, there was an 82% chance of maintaining MCyR for 5 years.
Dose reductions were carried out to decrease the risk of arterial occlusive events. Arterial occlusive events are those caused by narrowing of arteries. More than 90% of patients who had MCyR or MMR maintained a response to ponatinib 40 months after dose reductions.
The estimated 5-year overall survival (time from treatment until death from any cause) was 73%. The most common treatment related side effects were a rash in 47%, abdominal pain in 46%, thrombocytopenia (low platelet count) in 46%, headache in 43%, dry skin in 42% and constipation in 41%.
The cumulative incidence of arterial occlusive events in CP-CML patients increased over time to 31%. Exposure-adjusted incidence of new arterial occlusive events did not increase over time.
The bottom line
This study concluded that ponatinib was safe and effective in patients with CP-CML, regardless of dose reductions.
The fine print
This study was funded by ARIAD Pharmaceuticals, the manufacturers of ponatinib.
Published By :
Blood
Date :
Mar 22, 2018
