Chemotherapy-free induction and consolidation first-line treatment with dasatinib and blinatumomab is associated with a high incidence of molecular response and survival in adults with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL), according to a study published in the Oct. 22 issue of the New England Journal of Medicine.
Robin Foà, M.D., from Sapienza University of Rome, and colleagues conducted a single-group phase 2 trial of first-line therapy in newly diagnosed Ph-positive ALL. Sixty-three adults received dasatinib plus glucocorticoids followed by two cycles of blinatumomab.
The researchers found that 98 percent of patients had complete remission. Twenty-nine percent of the patients had a molecular response at the end of dasatinib induction (day 85), and this increased to 60 percent after two cycles of blinatumomab; a further increase in the percentage of patients with a molecular response occurred after additional blinatumomab cycles. Overall survival was 95 percent and disease-free survival was 88 percent at a median follow-up of 18 months. Patients who had an IKZF1 deletion plus additional genetic aberrations had lower disease-free survival. In six patients who had increased minimal residual disease during induction therapy, ABL1 mutations were detected; all were cleared by blinatumomab. There were six relapses and 21 adverse events of grade 3 or higher. Twenty-four patients received a stem cell allograft and one death was associated with transplantation.
“This combination was associated with high incidences of complete hematologic response and molecular response and with impressive survival at 18 months,” the authors write.