Frontline combination of dasatinib and low-intensity chemotherapy in adults with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia

BackgroundStudies on dasatinib-based low-intensity induction regimens and post-remission strategies are limited in China. Therefore, we conducted a single-center phase 2 trial in newly diagnosed adult patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) to establish the efficacy and safety of this treatment approach.Research design and methodsPatients received one month of dasatinib plus low-intensity chemotherapy and two months of dasatinib monotherapy for induction, followed by a single course of high-dose methotrexate for consolidation. Subsequently, they underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) or tyrosine kinase inhibitor (TKI)-based treatment for maintenance therapy between October 2015 and August 2022.ResultsTwenty-two patients were enrolled. Median age was 45 years (range, 20-71). The rates of major and complete molecular responses in the third month were 18.2% and 40.9% respectively. With a median follow-up of 15 months (range, 5-89), the estimated 3-year disease-free survival (DFS) and overall survival (OS) were 52.4% and 73.2%, respectively. The TKI-based cohort had a significantly poorer DFS (p = 0.014) and OS (p = 0.008) than the allo-HSCT cohort.ConclusionsOur results suggest that dasatinib-based low-intensity chemotherapy is safe and effective as an induction strategy in the Chinese population. Allo-HSCT plays a crucial role in the long-term outcomes of patients with Ph+ ALL.Clinical trial registrationThe trial was registered at ClinicalTrials.gov as NCT02690922.