Adherence to treatment with imatinib in chronic myeloid leukemia: a study of the first decade of responses obtained at a Brazilian hospital

Abstract

ObjectiveThe aim of this study was to identify the reasons for failure in adherence to imatinib mesylate treatment in chronic myeloid leukemia. MethodsA retrospective review was performed of 100 non-electronic records of patients with Ph+ chronic myeloid leukemia treated with imatinib mesylate. The study period was from January 2001 to January2011. Data were analyzed by Chi-Square and Correspondence analysis using the Statistical Analysis System software package. ResultsAt the beginning of treatment 41% of patients were in advanced stages of the disease. The unavailability of the drug (44.8%) and myelotoxicity (25.7%) were the most frequent reasons for interruption. The adherence rate was < 90% in 47% of the cases. The low adherence influenced the cytogenetic response (p-value = 0.020) and molecular response (p-value = 0.001). Very high adherence (> 95%) induced complete cytogenetic response, major cytogenetic response and major molecular response. ConclusionThe population of this study obtained lower-than-expected therapeutic responses compared to other studies.