High-dose (HD) imatinib in patients (pts) with previously untreated chronic myeloid leukemia (CML) in early chronic phase (CP): preliminary results of a multicenter community based trial

6518 Background: A recent single center study suggests that using HD imatinib (800 mg/day) results in significant molecular responses for many patients. We therefore initiated a multicenter community-based single-arm phase II trial of HD imatinib in pts with early CP CML. Methods: Pts were ≥18 years (yrs), in early CP (≤6 months from diagnosis), without prior therapy except for ≤1 month of imatinib or hydroxyurea, and with normal organ function. Pts received imatinib 400 mg twice daily and dose was adjusted for grade ≥3 toxicity; filgrastim was encouraged for pts with grade ≥2 neutropenia. Results: To date, 36 pts have been enrolled in 20 institutions with a median follow-up of 5 months (mos) (0.5–9 mos). The median age is 51 yrs (28–76 yrs). Nineteen patients (53%) had hemoglobin 450 x109/L. According to the Sokal classification, 14 (39 %), 18 (50%), and 3(8%) were in the low, intermediate and high-risk groups, respectively. Twenty seven pts have had a molecular analy...