FLORENCE: a randomized, double-blind, phase III pivotal study of febuxostat versus allopurinol for the prevention of tumor lysis syndrome (TLS) in patients with hematologic malignancies at intermediate to high TLS risk.

BACKGROUND: Serum uric acid (sUA) control is of key relevance in tumor lysis syndrome (TLS) prevention as it correlates with both TLS and renal event risk. We sought to determine whether febuxostat fixed dose achieves a better sUA control than allopurinol while preserving renal function in TLS prevention. PATIENTS AND METHODS: Patients with hematologic malignancies at intermediate to high TLS risk grade were randomized to receive febuxostat or allopurinol, starting 2 days before induction chemotherapy, for 7-9 days. Study treatment was blinded, whereas daily dose (low/standard/high containing allopurinol 200/300/600 mg, respectively, or fixed febuxostat 120 mg) depended on the investigator's choice. The co-primary end points, sUA area under curve (AUC sUA1-8) and serum creatinine change, were assessed from baseline to day 8 and analyzed through analysis of covariance with two-sided overall significance level of 5%. Secondary end points included treatment responder rate, laboratory and clinical TLS incidence and safety. RESULTS: A total of 346 patients (82.1% intermediate TLS risk; 82.7% assigned to standard dose) were randomized. Mean AUC sUA1-8 was 514.0 ± 225.71 versus 708.0 ± 234.42 mgxh/dl (P < 0.0001) in favor of febuxostat. Mean serum creatinine change was -0.83 ± 26.98% and -4.92 ± 16.70% for febuxostat and allopurinol, respectively (P = 0.0903). No differences among secondary efficacy end points were detected. Drug-related adverse events occurred in 6.4% of patients in both arms. CONCLUSION: In the largest adult trial carried out in TLS prevention, febuxostat achieved a significant superior sUA control with one fixed dose in comparison to allopurinol with comparable renal function preservation and safety profile. CLINICAL TRIAL REGISTRATION: NCT01724528.

3q21 and 3q26 cytogenetic abnormalities in acute myeloblastic leukemia: biological and clinical features.

BACKGROUND AND OBJECTIVE: Acute myeloblastic leukemia (AML) with features of myelodysplastic syndrome (MDS) and abnormalities of megakaryocytopoiesis is often characterized by cytogenetic aberrations of the 3q21 and 3q26 bands involving inv(3)(q21q26) and (3;3)(q21;q26). These aberrations have been described in all FAB subtypes with the exception of M3, and in MDS and in megakaryoblastic crisis of chronic myeloid leukemia. We reviewed the biological and clinical features of 10 cases of AML with inv(3)(q21q26) and t(3;3)(q21;q26). DESIGN AND METHODS: Four hundred and sixteen patients with AML were studied in our Institute by cytogenetic analysis and 10 (2.4%) showed inv(3)(q21q26) (7 patients) or t(3;3)(q21;q26) (3 patients): 7 males, 3 females; median age, 43.5 yrs. We also used RT-PCR to investigate the pattern of expression of the EVI-1 gene in 5 patients. RESULTS: Additional chromosomal changes were demonstrated in 6 patients. In 5/10 cases a preceding MDS had been observed. A possible occupational exposure was established in 2 patients (a farmer and an histologist employing organic solvents) and another patient had a therapy-related leukemia. AML subtype was M1 in 9 patients and M2 in 1. A variable excess of micromegakaryocytes was observed in all the patients. In 5 patients the platelet count was normal or increased (median number: 172. 5x10(9)/L; range 55-440). Expression of EVI-1 gene was present in all the 5 patients studied. The clinical course and outcome was extremely poor: 9/10 patients were resistant and 1 patient showed a partial remission after induction therapy. Of the 9 patients resistant to the first line chemotherapy, 7 were also resistant to the second line chemotherapy. Three patients obtained a morphologic complete remission after third line chemotherapy (duration 1, 3 and 6 months); 2 of them were submitted to autologous bone marrow transplantation, but relapsed after 1 and 3 months. The median overall survival was 5.5 months. INTERPRETATION AND CONCLUSIONS: Our findings evidence a strong correlation between 3q21q26 chromosomal aberrations, abnormalities of megakaryocytopoiesis and lack of response to conventional chemotherapy and support the diagnostic and prognostic relevance of chromosome characterization in the classification of AML.