Efficacy and safety of flumatinib in the treatment of newly diagnosed chronic myeloid leukemia in the chronic phase: A real-world single-center retrospective study, with a focus on premature drug discontinuation

Purpose: To assess the real -world efficacy and safety of flumatinib as first -line and post -line treatments for chronic myeloid leukemia in the chronic phase (CML-CP). Results: Among 141 patients receiving flumatinib as first -line and post -line treatment, the 12 -month major molecular response (MMR) rates were 69.4% and 67.6%, respectively. The median time to response was 6 and 10.5 months, respectively. In post -line treatment, the early molecular response (EMR) of flumatinib as secondline is significantly superior to that of third -line treatment (3 -month EMR rate: 79.2% vs. 39.3%, P <0.001; 3month MMR rate: 45.8% vs. 21.4%, P =0.033). Contrastively, patients who switched to flumatinib due to intolerance had significantly higher MMR rates at 3, 6, and 12 months compared to patients who switched due to inadequate response (60.6% vs. 24.2%, P =0.003; 66.7% vs. 36.0%, P =0.027; 84.2% vs. 50.0%, P =0.038). Premature drug discontinuation was observed in 28.4% of the patients. Grades 3 -4 hematologic adverse events (AEs) were identified as independent risk factors for premature drug discontinuation. Patients who discontinued treatment and those who previously received only imatinib therapy had a poorer molecular response and failurefree survival. Conclusions: Flumatinib demonstrates favorable efficacy and safety. Treatment discontinuation can result in a poorer molecular response and long-term prognosis.