Dasatinib plus prednisone as induction and consolidation for adults with Ph‐positive acute lymphoblastic leukaemia: A single‐arm, multicentre, phase 2 trial

Summary To reducing chemotherapy‐related toxicity, the chemo‐free regimens become a new trend of Ph + ALL treatment. Therefore, we conducted a phase 2 trial of dasatinib plus prednisone, as induction (Course I) and early consolidation (Courses II and III) treating newly diagnosed Ph + ALL. The trial was registered at www.chictr.org.cn , ChiCTR2000038053. Forty‐one patients were enrolled from 15 hospitals. The complete remission (CR) was 95% (39/41), including two elderly induction deaths. By the end of Course III, 25.6% (10/39) of patients achieved a complete molecular response. With a median follow‐up of 15.4 months, 2‐year disease‐free survival (DFS) were 100% and 33% for patients who receiving haematopoietic stem cell transplantation (HSCT) at CR1 and receiving chemotherapy alone respectively. When censored at time of HSCT, 2‐year DFS were 51% and 45% for young and elderly patients ( p = 0.987). 2‐year overall survival were 45%, 86% and 100% for patients without HSCT, receiving HSCT after relapse and receiving HSCT at CR1 respectively. A total of 12 patients had marrow recurrences and one had CNS relapse, with 38% occurred early (between Courses I and III). IKZF1 gene deletion was shown to be associated with relapse ( p = 0.019). This chemo‐free induction and early consolidation regimen was efficacious and well‐tolerated in de novo Ph + ALL. Allogeneic HSCT conferred definite survival advantage after chemo‐free induction.