‘Faster and Deeper Responses’ With Dasatinib vs Imatinib in Chronic-Phase CML Patients
Dasatinib (Sprycel) resulted in “faster and deeper responses” compared to imatinib (Gleevec) among patients with newly diagnosed chronic-phase chronic myeloid leukemia (CML), according to a 3-year follow-up of the randomized phase III DASISION (Dasatinib vs Imatinib Safety In Treatment-Naive CML patients) trial. Deeper responses at 3, 6, and 12 months were associated with better 3-year progression-free and overall survival, Jabbour et al reported in Blood.
Patients eligible for the trial were adults with newly diagnosed Philadelphia chromosome–positive, chronic-phase CML who had adequate organ function and no other serious medical conditions, the investigators explained. Patients were randomly assigned to receive 100 mg of dasatinib (n = 259) or 400 mg of imatinib (n = 260) once daily. Dose escalations were permitted up to 140 mg for dasatinib and 600 to 800 mg for imatinib.
“Median time to complete cytogenetic response was 3 vs 6 months with dasatinib vs imatinib,” the researchers wrote. Higher response rates were observed at 1 year for patients with dasatinib compared with imatinib and were maintained at 3 years.
Treatment Well Tolerated in Both Groups
Treatment was well tolerated in both the dasatinib and imatinib groups, and most adverse events occurred in the first year. “With the exception of pleural effusion, all of the most common (≥ 10%, any grade) drug-related nonhematologic [adverse events] were either lower with dasatinib or comparable between arms,” the investigators noted. “Infection (drug-related and not drug-related) occurred in 33% of patients receiving dasatinib and 25% of patients receiving imatinib by 36 months.”
Patients receiving dasatinib had higher rates of thrombocytopenia (19% vs 11% with imatinib). Rates for neutropenia were 24% with dasatinib vs 21% for imatinib, and for anemia, 12% vs 9%.
“Except for grade 3/4 hypophosphatemia (dasatinib, 7%; imatinib, 28%), other types of grade 3/4 biochemical abnormalities occurred in ≤ 3% of patients and with a similar frequency in the dasatinib and imatinib arms,” the authors added.
“The achievement of an early molecular response was predictive of improved [progression-free and overall survival], supporting new milestones for optimal response in patients with early [chronic-phase CML] treated with tyrosine kinase inhibitors,” the investigators concluded.
Hagop M. Kantarjian, MD, of The University of Texas MD Anderson Cancer Center, Houston, is the corresponding author for the Blood article.
The study was sponsored by Bristol-Myers Squibb. For full disclosures of the study authors, visit bloodjournal.hematologylibrary.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
