Targeted chronic myeloid leukemia therapy: seeking a cure

Area of Science:

• Hematology
• Oncology
• Molecular Biology

Background:

• Chronic Myeloid Leukemia (CML) is a hematopoietic stem cell cancer driven by the BCR-ABL fusion protein.
• CML progresses from an indolent chronic phase (CP) to accelerated (AP) and blast phases (BP) with poor prognosis.
• Allogeneic bone marrow transplant (BMT) is curative but associated with high treatment-related mortality.

Purpose of the Study:

• To review the evolution of CML therapy.
• To discuss pre-imatinib and imatinib-based treatment strategies.
• To examine clinical efficacy and mechanisms of imatinib resistance.

Main Methods:

• Review of historical and contemporary CML treatment modalities.
• Analysis of clinical trial data for imatinib efficacy.
• Discussion of BCR-ABL tyrosine kinase inhibition and resistance mechanisms.

Main Results:

• Cytoreductive chemotherapy and interferon (IFN) showed limited efficacy and significant toxicity.
• Imatinib targets the BCR-ABL tyrosine kinase, achieving high complete hematologic response (CHR) rates (>90%) in CP-CML.
• Imatinib demonstrates low toxicity in CP-CML, with manageable side effects.

Conclusions:

• Imatinib is the standard of care for most CP-CML patients, with >90% 5-year survival rates.
• Allogeneic BMT remains an option for refractory or intolerant patients.
• Imatinib resistance, often due to BCR-ABL mutations, necessitates the development of next-generation inhibitors.