Similar outcome of patients with chronic myeloid leukemia treated with imatinib in or out of clinical trials

Abstract

Introduction: Outcomes of CML-CP patients treated in clinical trials are frequently perceived to be not representative of those treated outside of clinical trials.

Patients and methods: We investigated the outcomes of patients receiving imatinib outside of a clinical trial (off protocol) or in a clinical trial (on protocol) for CML-CP.

Results: We identified 65 patients treated with imatinib off protocol and 71 patients treated on protocol with standard-dose imatinib. The overall complete cytogenetic response (CCyR) rate was 83% for patients treated on and off protocol. CCyR rates 12 months after initiation of imatinib were not statistically different (61% vs. 66%, respectively; P = .15). Patients treated off protocol had similar rates of overall major molecular response (72% vs. 73%) compared with the patients treated on protocol. The 5-year event-free survival rates were 84% and 86% for off and on protocol patients, respectively. There was also no significant difference in 5-year transformation free survival (94% vs. 96%) and overall survival (96% vs. 90%).

Conclusion: These results suggest that patients with CML treated outside of a clinical trial might have the same excellent outcome as those treated in a clinical trial provided they are followed with the same rigor.

Keywords: CML; Imatinib; Outside of a clinical trial; Prognosis; TKI.