Report on Response and Overall Survival of 128 Unselected, Consecutive AML Patients From the Austrian Azacitidine Registry (AAR) of the AGMT-Study Group

Abstract 4266

Twelve participating centers in Austria included 257 unselected, consecutive patients with MDS, CMML or AML, who received azacitidine (AZA) between 02/2007 and 07/2011, in the nationwide Austrian Azacitidine Registry (AAR) of the AGMT-study group. This registry was approved by the national Ethics Committee and includes 128 patients with AML of all FAB-subtypes, as well as de novo AML (39%), t-AML, MDS-AML and post-CMPD-AML.

This registry comprises a large number of patients with >30% bone marrow blasts (83/128) (currently off-label indication for AZA), as well as myeloproliferative AML (35/128), as defined by presence of >10.000 WBC/μ l at diagnosis. The AAR includes a high proportion of very old AML patients (median age 73a, 20% 75–79a, 24% >80a). Although the PS was generally low (22% ECOG-0, 47% ECOG-1), AML patients suffered from coronary artery disease (n=29), renal insufficiency (n=26), diabetes mellitus (n=21), a prior/concomitant solid tumor (n=17), COPD (n=14) and/or mild liver disease (n=13), respectively. Only 40% of all AML-patients included were treatment-naïve, whereas the rest was pretreated with G-CSF (12%), ESA (9%), ICT (3%) revlimid or thalidomide (6%), other agents (11%) and/or intensive chemotherapy (47%), respectively. Thus, this registry more accurately reflects a real-life treatment scenario, than most clinical trials that have strict inclusion/exclusion criteria.

In the 93 patients in whom pre-AZA cytogenetics were performed, 56.9%, 25.8% and 17.2% could be grouped into IPSS good, intermediate and poor risk categories, respectively. Of these, 43 patients had MDS-specific cytogenetic aberrations (5q-, +8, -7, -7q, -Y and -20q). Most AZA-cycles were applied s.c. (89%), whereas 11% were applied i.v. Median and mean number of AZA-cycles was 4.0 and 5.6 (range 1–24), respectively. 60% of patients predominantly received the FDA-approved d1-7 schedule, whereas the non-approved alternative schedules 5-2-2, d1-5 and ‘others’ were most often given in 17%, 16% and 7% of patients, respectively. The FDA-approved target dose (75mg/m² over 7 days) was achieved in 58% of all cycles and in 61% of patients, respectively.

Longitudinal repetitive analysis of serum GOT, GPT, bilirubin and creatinine over up to 24 cycles shows no relevant variation or worsening tendency of these parameters during treatment with AZA, including patients with reduced baseline renal and/or hepatic function.

Reasons for termination of treatment were death for any reason (26%), disease progression or relapse (27%), no response (6%), toxicity (7%), recurrent infectious complications (2%) and other reasons (23%). Adverse events will be presented in detail (number, grade, duration, hospitalization rate, effects on AZA (dose reductions/treatment pause/termination)).

Any kind of hematologic improvement (HI) was noted in 38% of patients. When looking at each lineage separately, 21/128 had HI-ery, 23/128 HI-PLT and 24/128 HI-neutrophils. 35/85 patients who were RBC-TD and 19/55 patients who were PLT-TD prior to AZA-treatment achieved transfusion independence (TI). In patients, in whom (repetitive) bone marrow analyses were performed for response evaluation (n= 56), the following best marrow responses were observed: CR (19.6%), marrow CR (7.1%), PR (33.9%), SD (30.4%) and primary PD (8.9%). At the time of writing, 35 patients had received ≤2 cycles. This number largely accounts for the patients in whom no bone marrow response evaluation was performed. The OR rate observed prior to 07/2011 was 38% (CR + marrow CR + PR + HI). When limiting response analysis to patients who received ≥2 AZA cycles, which is required for achievement of hematologic response by the IWG-criteria, ORR was 57%.

The median OS was 9.5mo (95%CI 8.15–10.9). In univariate analyses, ECOG >=2 (p=.0026), circulating blasts (9.3 vs. 24.8mo; p=.0014), IPSS poor risk cytogenetics (p=.0037) and failure to achieve any HI (8.6 vs. 22.4mo; p=.0001), significantly negatively impacted OS. Prior treatment with G-CSF and/or ESA, age >80a, WBC >10G/l, BM blasts >30%, LDH >225U/l, number of cytopenic lineages as well as RBC-TD and/or PLT-TD at baseline, did not significantly impact OS (p>0.05) (detailed statistics will be presented).

In conclusion, in this population of partly heavily pretreated very old patients with AML, AZA was well tolerated and yielded substantial clinical and hematological benefit, irrelevant of baseline BM blast or PB WBC count.