Brief Summary: The goal of this prospective, multicenter, open observational study is to assess the efficacy and safety of the treatment for acute lymphoblastic leukemia Ph' positive adult patients with approved combinations of chemotherapy and tyrosine kinase inhibitor (TKI). Efficay refers to the rate of Complete Molecular Response (BCR::ABL1/ABL1 ratio 0.01%) in eah treatment arm. Safety refers to measurement of i) Adverse events (AEs) and serious adverse events (SAEs) according to standard clinical and laboratory tests (hematology and chemistry, physical examination, vital sign measurements, and diagnostic tests), ii) incidence and degree of cytopenias and iii) incidence and degree of infections. Low-dose chemotherapy will be given together with the TKI imatinib to patients of all ages as induction to remission phase. Consolidation treatment will continue with low-dose chemotherapy with imatinib if the patient fullfills both criteria: to show a measurable residual disease (MRD) value lower than 0,01% at 3 month of therapy, and not showing IKZF1plus genetics Those patients have any of these 2 conditions will be considered high-risk patients and will recieve consolidation treatment intensification with low-dose chemotherapy plus ponatinib as TKI and allogeneic stem cell transplantation (allo SCT). The remaining patients (standard-risk) will receive maintenance chemotherapy together with imatinib or ponatinib and will not be submitted to alloSCT.

Detailed Description: The goal of this prospective, multicenter, open observational study is to assess the efficacy and safety of the treatment for acute lymphoblastic leukemia Ph' positive adult patients with approved combinations of chemotherapy and tyrosine kinase inhibitor (TKI). Efficay refers to the rate of Complete Molecular Response (BCR::ABL1/ABL1 ratio 0.01%) in each treatment arm. Safety refers to measurement of i) Adverse events (AEs) and serious adverse events (SAEs) according to standard clinical and laboratory tests (hematology and chemistry, physical examination, vital sign measurements, and diagnostic tests), ii) incidence and degree of cytopenias and iii) incidence and degree of infections. Low-dose chemotherapy induction phase with vincristine (dose 1.5 mg/m2 at days 1, 8, 15 and 22), dexamethasone (dose 40 mg days 1-2, 8-9,15-16 and 22-23) will be given together with the TKI imatinib (dose 600 mg from day to consolidation start) to all patients of all ages as induction to remission phase. Consolidation treatment will continue with low-dose chemotherapy with methotrexate (dose 1000 mg/m2 on day 1 with 24h infusion) and arabinoside of cytarabine (dose 1000 mg/m2/ days 1, 3 and 5 with 2h infusion) with imatinib (dose 600 mg per day) if the patient fullfills both criteria: i) to show a measurable residual disease (MRD) value \<0,01% at 3 month of therapy, and ii) not showing IKZF1plus genetics. Those patients having any of these 2 conditions will be considered high-risk patients and will recieve consolidation treatment intensification with low-dose chemotherapy (same as described above) plus ponatinib (dose 30 mg per day) as TKI and allogeneic stem cell transplantation (alloSCT) followed by maintenance chemotherapy with mercaptopurine (dose 50 mg/m2 on days 1 to 28) and methotrexate (dose 20 mg/m2 on days 1, 8, 15 and 22) together with imatinib (dose 600 mg per day) or ponatinib (15 mg per day) up to 5 years. The remaining patients (standard-risk) will receive maintenance chemotherapy (as described above) together with imatinib (dose 600 mg per day) or ponatinib (15 mg per day) up to 5 years and will not be submitted to alloSCT.