Dasatinib in early chronic-phase chronic myeloid leukemia

The current study explored the use of dasatinib as an initial treatment for early chronic phase chronic myeloid leukemia (CML). The authors concluded that dasatinib was a safe and effective first-line treatment.

The standard first-line treatment for CML is imatinib (Gleevac). Imatinib is a tyrosine kinase inhibitor (TKI). TKIs block a protein involved in cancer cell growth and spread. Imatinib leads to a complete cytogenic response (CCyR, a disappearance of the Philadelphia chromosome, the cause of CML) in 82% of patients. Some patients, however, do not reach or stay in CCyR.

Dasatinib is another TKI. It has been shown to lead to CCyR in roughly 50% of patients after imatinib failure. It is not clear whether it is effective as a first-line treatment.

The current study explored the use of dasatinib in patients with early chronic phase CML. 62 patients were randomly assigned to treatement with 100 mg of dasatinib once per day or 50 mg twice per day. Patients were treated until disease progression or until they experienced severe negative side effects. Patients were followed for an average of 24 months. 50 patients were included in the final analysis.

98% of patients achieved CCyR. 94% achieved CCyR by 6 months of treatment. 82% of patients achieved a major molecular response (no sign of the abnormal BCR-ABL gene, part of the Philadelphia chromosome). All patients were alive after 24 months. There was no significant differences between the treatment groups.

21% of patients experienced a serious decrease in neutrophils (type of white blood cell). 10% experienced a serious decrease in platelets (cells involved in blood clotting). Less severe side effects included muscle and joint pain, fatigue, rash, headache, and diarrhea. 48% of patients experienced treatment interruptions. The most common reasons were fluid buildup in the chest, shortness of breath, and headache.

This study concluded that dasatinib was a safe and effective first–line treatment for early chronic stage CML.