Azacitidine in Patients with Acute Myeloid Leukemia: Assessing the Potential Negative Impact of Elevated Baseline White Blood Cell Count on Outcome

Background Recent phase III data indicate that azacitidine (AZA) is active, and well tolerated, in patients with acute myeloid leukemia (AML) and baseline white blood cell (WBC) counts of Methods In this retrospective study of the Austrian AZA Registry (N=346), we assessed outcomes in patients with WHO-AML who received ≥1 dose of AZA, according to baseline WBC count. Patients were divided according to WBC Results A comparison of baseline characteristics between the two groups revealed significantly higher levels of serum lactate dehydrogenase (LDH), peripheral blood (PB) and bone marrow (BM) blasts in patients with WBC ≥15G/L vs those with WBC In the 1st line setting, overall response rate (ORR) was similar in the WBC In contrast, in the ≥2nd line setting, ORR was significantly higher in the WBC Different baseline factors appeared to significantly impact OS in the 0% and LDH >225IU/L negatively affected OS, irrespective of treatment line. Adverse cytogenetics reached statistical significance for the whole 3, primarily in the AZA 1st line setting. Conclusions Previous retrospective studies have suggested that WBC ≥15G/L has a negative impact on OS in AML patients treated with AZA.2,3 This report is the first to describe the impact of WBC ( 1. Dombret H, et al. Oral presentation at EHA 2014. Abstract LB-2433 2. Thepot S, et al. Am J Hematol 2014;89:410–6 3. van der Helm LH, et al. Leuk Res 2013;37:877–82 4. Cheson BD, et al. J Clin Oncol 2003;21:4642–9 5. Cheson BD, et al. Blood 2006;108:419–25 Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Pleyer: Celgene: Consultancy, Honoraria; AOP Orphan Pharmaceuticals: Honoraria; Novartis: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria. Off Label Use: Vidaza (azacitidine) is indicated for the treatment of adult AML patients who are not eligible for haematopoietic stem cell transplantation with 20–30 % blasts and multi-lineage dysplasia, according to WHO classification. This cohort also includes AML-patients with >30% bone marrow blasts.. Burgstaller:AOP Orphan Pharmaceuticals: Honoraria; Novartis: Honoraria; Mundipharma: Honoraria; Celgene: Consultancy. Stauder:Ratiopharm: Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Novartis: Research Funding. Girschikofsky:Pfizer: Honoraria, Research Funding; Mundipharm: Consultancy, Honoraria. Pfeilstöcker:Janssen-Cilag: Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Lang:Celgene: Consultancy. Sperr:Phadia: Research Funding; Novartis: Honoraria; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Valent:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Greil:Amgen: Honoraria, Research Funding; Eisai: Honoraria; Mundipharma: Honoraria, Research Funding; Merck: Honoraria; Janssen-Cilag: Honoraria; Genentech: Honoraria, Research Funding; Novartis: Honoraria; Astra-Zeneca: Honoraria; Boehringer-Ingelheim: Honoraria; Pfizer: Honoraria, Research Funding; Roche: Honoraria; Sanofi Aventis: Honoraria; GSK: Research Funding; Ratiopharm: Research Funding; Celgene: Consultancy, Research Funding; Cephalon: Consultancy, Honoraria, Research Funding; Bristol-Myers-Squibb: Consultancy, Honoraria.