Imatinib mesylate in chronic myeloid leukemia: frontline treatment and long-term outcomes

SUMMARY

The tyrosine kinase inhibitor Imatinib Mesylate has dramatically improved the clinical outcome of chronic myeloid leukemia (CML) patients in the chronic phase of the disease, generating unprecedented rates of complete hematologic and cytogenetic responses and sustained reductions in BCR-ABL transcripts. Here, we present an overview on the efficacy and safety of Imatinib and describe the most important clinical studies employing this drug for the frontline treatment of chronic phase CML. We also discuss recent reports describing the long-term outcome of patients receiving Imatinib for their disease. The imminent availability of generic forms of Imatinib coupled with the approval of expensive second-generation tyrosine kinase inhibitors underlines an unmet need for early molecular parameters that may distinguish CML patients likely to benefit from the drug from those that should receive alternative forms of treatment.

KEYWORDS:

• Chronic myeloid leukemia
• BCR-ABL
• Imatinib Mesylate
• CML therapy
• tyrosine kinase inhibitors
• unmet medical needs

Financial and competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Key issues

• The introduction of the drug imatinib mesylate has dramatically improved the clinical outcome of chronic myeloid leukemia (CML) patients.

• Frontline imatinib therapy has generated unprecedented rates of complete hematologic and cytogenetic responses and sustained reductions in BCR-ABL transcripts.

• The achievement of profound deep molecular responses raised the interest in exploring the option of IM-therapy discontinuation in those patients who gained a sustained complete molecular remission.

• The imminent availability of generic forms of imatinib coupled with the approval of expensive second-generation tyrosine kinase inhibitors (2G-TKIs) highlights an unmet need for early molecular parameters that may distinguish CML patients likely to benefit from the drug from those that should receive alternative forms of treatment.

• Presently, no guidelines or recommendations address this pivotal therapeutic issue.