Outcomes and prognostic factors of adults with refractory or relapsed T-cell acute lymphoblastic leukemia included in measurable residual disease-oriented trials.

Despite high complete remission (CR) rates with frontline therapy, relapses are frequent in adults with T-cell acute lymphoblastic leukemia (T-ALL) with limited salvage options. We analyzed the outcomes and prognostic factors for CR to salvage therapy and overall survival (OS) of patients with R/R T-ALL included in two prospective measurable residual disease-oriented trials. Seventy-five patients (70 relapsed, 5 refractory) were identified. Relapses occurred in bone marrow, isolated or combined in 50 patients, and in the central nervous system (CNS; isolated or combined) in 20. Second CR was attained in 30/75 patients (40%). Treatment with FLAG-Ida and isolated CNS relapse were independently associated with a higher CR rate after first salvage therapy. The median OS was 6.2 (95% confidence interval [CI], 3.9-8.6) months, with a 4-year OS probability of 18% (95% CI, 9%-27%). No differences in survival were observed according to the treatment with hematopoietic stem cell transplantation in patients in CR after first salvage therapy. Multivariable analysis showed a ≥12-month interval between first CR and relapse, CR after first salvage therapy and isolated CNS relapse as favorable prognostic factors for OS with hazard ratios (HR) (95% CI) of 1.931 (1.109-3.362), 2.958 (1.640-5.334), and 2.976 (1.157-7.655), respectively. This study confirms the poor outcomes of adults with R/R T-ALL among whom FLAG-Ida was the best of the rescue therapies evaluated. Late relapse, CR after first rescue therapy and isolated CNS relapse showed prognostic impact on survival. More effective rescue therapies are needed in adults with R/R T-ALL.

Chemotherapy or allogeneic transplantation in high-risk Philadelphia chromosome-negative adult lymphoblastic leukemia.

The need for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in adults with Philadelphia chromosome-negative (Ph-) acute lymphoblastic leukemia (ALL) with high-risk (HR) features and adequate measurable residual disease (MRD) clearance remains unclear. The aim of the ALL-HR-11 trial was to evaluate the outcomes of HR Ph- adult ALL patients following chemotherapy or allo-HSCT administered based on end-induction and consolidation MRD levels. Patients aged 15 to 60 years with HR-ALL in complete response (CR) and MRD levels (centrally assessed by 8-color flow cytometry) <0.1% after induction and <0.01% after early consolidation were assigned to receive delayed consolidation and maintenance therapy up to 2 years in CR. The remaining patients were allocated to allo-HSCT. CR was attained in 315/348 patients (91%), with MRD <0.1% after induction in 220/289 patients (76%). By intention-to-treat, 218 patients were assigned to chemotherapy and 106 to allo-HSCT. The 5-year (±95% confidence interval) cumulative incidence of relapse (CIR), overall survival (OS), and event-free survival probabilities for the whole series were 43% ± 7%, 49% ± 7%, and 40% ± 6%, respectively, with CIR and OS rates of 45% ± 8% and 59% ± 9% for patients assigned to chemotherapy and of 40% ± 12% and 38% ± 11% for those assigned to allo-HSCT, respectively. Our results show that avoiding allo-HSCT does not hamper the outcomes of HR Ph- adult ALL patients up to 60 years with adequate MRD response after induction and consolidation. Better postremission alternative therapies are especially needed for patients with poor MRD clearance. This trial was registered at www.clinicaltrials.gov as # NCT01540812.

Efficacy and safety of native versus pegylated Escherichia coli asparaginase for treatment of adults with high-risk, Philadelphia chromosome-negative acute lymphoblastic leukemia.

Native or pegylated (PEG) asparaginase (ASP) are commonly used in treatment of acute lymphoblastic leukemia (ALL), but have been scarcely compared in the same trial in adult patients. Native vs. PEG-ASP administered according to availability in each center were prospectively evaluated in adults with high-risk ALL. Ninety-one patients received native ASP and 35 PEG-ASP in induction. No significant differences were observed in complete remission, minimal residual disease levels after induction and after consolidation, disease-free survival, and overall survival. No significant differences in grades 3-4 toxicity were observed in the induction period, although a trend for higher hepatic toxicity was observed in patients receiving PEG-ASP. In this trial the type of ASP did not influence patient response and outcome.

Feasibility and results of subtype-oriented protocols in older adults and fit elderly patients with acute lymphoblastic leukemia: Results of three prospective parallel trials from the PETHEMA group.

BACKGROUND AND OBJECTIVE: The prognosis of acute lymphoblastic leukemia (ALL) is poor in older adults and elderly patients, and subtype-oriented prospective trials are scarce in these patients. We present the results of three prospective parallel subtype-oriented protocols in fit patients older than 55 years. PATIENTS AND METHODS: In 2008, three prospective phase II trials in patients older than 55 years were activated: ALLOLD07 for Philadephia (Ph) chromosome-negative ALL, ALLOPH07 for Ph-positive ALL, and BURKIMAB08 for mature B-ALL. Early death (ED), complete remission (CR), disease-free survival (DFS), overall survival (OS) and toxicity were analyzed. RESULTS: 56, 53 and 21 patients from the ALLOLD07, ALLOPH07 and BURKIMAB08 trials, respectively, were evaluable. CR was 74%, 87% and 70%, with an ED rate of 13%, 11% and 15%, respectively. The medians of DFS were 8 and 38 months for ALLOLD07 and ALLOPH07 protocols, not being achieved in the BURKIMAB08 trial (p=0.001), and the median OS was 12, 37 and 25 months, respectively (p=0.030). Neutropenia, thrombocytopenia and infections were less frequent in the ALLOPH07 trial vs. ALLOLD07 and BURKIMAB trials, and renal toxicity and mucositis were more frequent in the BURKIMAB08 trial vs. the ALLOLD07 and ALLOPH07 trials. ECOG score and WBC count had prognostic significance for OS in ALLOPH07 and BURKIMAB08 trials, whereas no prognostic factors were identified in ALLOLD07 protocol. CONCLUSION: Subtype-oriented treatment had an impact in the outcome of older adults with ALL. The poorest outcome was observed in Ph-negative non-Mature B-cell ALL patients, for whom improvements in therapy are clearly needed.