Adverse events associated with escalating imatinib versus switching to dasatinib in patients with chronic myelegenous leukemia

7092 Background: After initial therapy with imatinib, some chronic myelegenous leukemia (CML) patients may require dose escalation or switching to another BCR/ABL kinase inhibitor to achieve the desired response. This study compared adverse events associated with either escalation of imatinib or switching to dasatinib. Methods: Two large administrative claims databases were combined (MarketScan and Ingenix Impact) to extract deidentified information on 17,382 patients diagnosed with CML (ICD-9 code: 205.1) from January 1999 to March 2008. 474 patients (dose escalators) had their dose of imatinib increased at some point to >400 mg/day but were never given dasatinib, while 175 patients were switched to dasatinib with or without dose escalation of imatinib (switchers). Patients were followed from the index date to treatment discontinuation or end of eligibility. Cox proportional-hazard models were used to compare the risk of common adverse events (AEs) associated with escalation or switching to dasatinib, co...