Treatment outcome of 100 chronic myeloid leukemia patients using nilotinib as the 2nd line therapy

Abstract

Background: Nilotinib is a potent and selective BCR-ABL inhibitor approved for use in patients with newly diagnosed chronic myeloid leukemia (CML) in chronic phase (CML-CP) and in patients with CML-CP and accelerated phase (CML-AP) who are resistant to or intolerant of imatinib. Patients with imatinib-resistant CML, nilotinib treatment resulted in a significant proportion of patients achieving hematologic and cytogenetic responses in all phases of CML. Objectives: The aim of the present study was to assess the treatment outcomes in term of the molecular response rate of CML patients using Nilotinib as the second-line therapy after failure of imatinib therapy. Patients and Methods: A prospective study conducted between December 2014 and December 2016 in Baghdad Teaching Hospital and National Centre of hematology. A total of 100 patients, who were on nilotinib therapy as the second-line therapy, were enrolled in this study. The molecular response was assessed using real-time quantitative polymerase chain reaction (RQ-PCR). Major molecular response (MMR) was defined as the BCR-ABL1 of <0.1% by RQ-PCR. Results: The median age was 39 years, 59 were female and 41 were male. Fifty-three patients were classified as high-risk group, and 47 patients were as low risk. The BCR-ABL transcription level had a significant reduction from baseline at 3 months (P = 0.035) and the reduction from 3 months to 6 months was also statistically significant (P < 0.001). Comparing the patients who achieved MMR versus NO MMR, there was a significant association between low European Treatment and Outcome Study score and achieving MMR. An estimated 24 months overall survival (OS) is 95%. Conclusion: This study concluded that nilotinib is an effective therapeutic option for patients with CML-CP-resistant to imatinib therapy. Nilotinib treatment resulted in a high-OS rate and was well tolerated.