Second generation tyrosine kinase-inhibitors (TKI) have been claimed to represent now the first-choice therapy for chronic myeloid leukemia (CML). Indeed, they generally induce faster and deeper molecular responses compared to imatinib that, however, is equally effective in at least 50% of patients. Moreover, some recent reports have questioned the long term safety of dasatinib and nilotinib. Therefore, upfront imatinib with early shift to second generation TKI for patients with slow/incomplete response might be as effective as front-line second generation TKI, with a possibly better safety profile. We retrospectively evaluated 91 chronic phase CML patients (median follow-up 57 months, median age 61 years), treated front-line with standard-dose imatinib and early therapy modifications (at 3-12 months) in case of unsatisfactory response or intolerance. Thirty-three patients (24 with unsatisfactory response, 9 intolerant) changed therapy, either by increasing imatinib dose (11/91) or by switching to second generation TKI (22 directly, 4 after high-dose imatinib). Globally, our strategy led to complete cytogenetic response (CCyR) in 98% of the patients, major molecular response (MMR) in 88% and molecular response 4 logs (MR(4.0) ) in 62%. Three patients in CCyR (3%), 2 of them in MMR too, suddenly progressed to blastic phase. At the last follow-up nine patients had died, seven of CML-unrelated causes and two only of CML progression. These results suggest that our strategy could be as effective as front line second generation TKI, with most of patients still receiving imatinib, a drug of better known long-term side effects and lower cost.
Copyright © 2013 Wiley Periodicals, Inc.