Remission from B-Cell ALL with Chemo-Free Induction Therapy

Tyrosine kinase inhibitors (TKI) targeting BCR-ABL are an integral component of initial therapy for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). Investigators from the multicenter, phase 2 D-ALBA trial reported long-term outcomes for 63 patients (age range, 24–82; median, 54) treated with the TKI dasatinib plus the CD19/CD3 T-cell–engaging bispecific monoclonal antibody blinatumomab. Patients received 12-week cycles of corticosteroids for 7 days, dasatinib (140 mg/day) plus corticosteroids for 23 days, and dasatinib alone for 54 days. Daily dasatinib was continued during consolidation with 2 or more cycles of blinatumomab. Central nervous system prophylaxis was administered via lumbar puncture at multiple time points. Serial minimal residual disease was analyzed in bone marrow by reverse transcriptase-polymerase chain reaction.

The complete remission rate was 98%. The molecular response rate was 60% following cycle 2 of blinatumomab (previously reported; N Engl J Med 2020; 383:1613) and increased to 93% at 12 months. At a median follow-up of 53 months, disease-free survival (DFS) was 75.8%, and overall survival was 80.7%. DFS was significantly lower in patients without molecular response at the end of induction and in those with the IKZF₁^plus mutation. Of 29 patients treated with ongoing TKI therapy but not cytotoxic chemotherapy or stem cell transplantation, 28 remained in complete hematologic remission at a median 48 months' follow-up.