According to updated results from a Phase III clinical trial, Tasigna® (nilotinib) continues to be more effective than Gleevec® (imatinib) for the initial treatment of adult patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia (Ph+ CML) in chronic phase. These results were published in Lancet Oncology.
Each year in the United States, approximately 5,000 people are diagnosed with chronic myeloid leukemia (CML). Most cases of CML are characterized by a chromosomal abnormality—the Philadelphia chromosome—in which genetic material is exchanged between chromosome 9 and chromosome 22. This exchange brings together two genes: BCR and ABL. The combination of these two genes into the single BCR-ABL gene results in the production of a protein that contributes to uncontrolled cell growth.
Recognition of the pivotal role of the BCR-ABL protein in CML led to the development of Gleevec® (imatinib), which blocks the activity of this protein. Gleevec produced high rates of remission among patients with chronic-phase CML and dramatically changed the treatment of this disease. Newer drugs that target the BCR-ABL protein include Tasigna and Sprycel® (dasatinib).
To compare Tasigna with Gleevec, researchers conducted the Phase III ENESTnd trial (Evaluating Nilotinib Efficacy and Safety in Clinical Trials of Newly Diagnosed Ph+ CML patients). The study enrolled 846 adult patients with newly diagnosed, Ph+ CML in chronic phase. Patients were assigned to be treated with Tasigna 300 mg twice daily, Tasigna 400 mg twice daily, or Gleevec 400 mg once daily. Patients have now been followed for at least 24 months.
- A major molecular response was achieved by 71% of patients taking Tasigna 300 mg twice daily, 67% of patients taking Tasigna 400 mg twice daily, and 44% of patients taking Gleevec 400 mg once daily.
- Patients treated with Tasigna were less likely than patients treated with Gleevec to progress to advanced stages of CML.
- Two-year overall survival was similar in the three study groups.
The results of this study continue to suggest that Tasigna is more effective than Gleevec for the initial treatment of adult patients with Ph+ CML in chronic phase.
Reference: Kantarjian HM, Hochhaus A, Saglio G et al. Nilotinib versus imatinib for the treatment of patients with newly diagnosed chronic phase, Philadelphia chromosome-positive, chronic myeloid leukaemia: 24-month minimum follow-up of the phase 3 randomised ENESTnd trial. Lancet Oncology. 2011;12:841-51.