DP080 | LOW INCIDENCE OF FUNGAL INFECTIONS IN NEWLY DIAGNOSED AML PATIENTS TREATED WITH AZACITIDINE AND VENETOCLAX IN THE ABSENCE OF POSACONAZOLE PROPHYLAXIS. A SINGLE-CENTER EXPERIENCE.

Venetoclax combined with azacitidine has become the SOC for elderly/unfit ND-AML pts, yielding unprecedented efficacy with a manageable toxicity profile. Although recommended during the first cycles, the role of antifungal prophylaxis in this scenario is not well defined; moreover, the conduit regarding antibacterial prophylaxis is heterogeneous. We report the outcomes with a focus on infectious events of 85 pts with ND-AML treated at our institution with AZA-VEN from 2020 to 2025.Overall, 521 cycles were administered; median cycle n° per pt was 6 (1-33). Forty-seven out of 85 pts (55%) received cycle 1 as inpatients. Levofloxacin prophylaxis was applied for all outpatients in case of ANC <500/mm3. G-CSF was used in all patients in complete remission (CR) if ANC <500/mm3. Only 6/85 pts (7%) received posaconazole prophylaxis, during the first cycle exclusively. CCR rate was 50.6%. Overall, 33/85 pts (38.8%) experienced an infectious event (G>2: 24/85, 28%; G5: 2/85, 2.3%). Twenty-three bacterial events were observed (G-negative sepsis, n=9; pneumoniae, n=4; G-positive sepsis, n=2; dental abscess, n=2; UTI, n=1; necrotizing enterocolitis, n=1; other, n=4) mostly during cycle 1, 18/23 were G3-4, 2 were fatal and both occurred in refractory pts.None of the bacterial events was sustained by MDROs.Fungal infections occurred in 3 pts (proven, n=1; probable, n=2), with Aspergillus as the only involved pathogen, were all graded G3 and occurred in pts with uncontrolled disease not receiving posaconazole prophylaxis. Eighteen viral events were observed. Sars-Cov-2 was the most frequently involved pathogen (n=11), but infections were paucisymptomatic and none was fatal.VZV reactivation occurred in 2 pts. Other infections were sustained by respiratory viruses and were mild. FUO were experienced by 18 pts, mostly during cycle 1 (n=14) and were mostly deemed to be related to cytolysis or paraneoplastic phenomena. Hospitalization during cycle 1 was associated with a higher incidence of infections (29.7% inpatients; 21% outpatients, P=NS), likely because of patient selection. The only factor with a borderline significant association with a higher incidence of infectious events was failure to achieve CR (CCR pts, 16%; refractory pts, 35%; p=0.0722). Overall, our data highlight a relatively low rate of infectious events in elderly/unfit, ND-AML pts treated with AZA-VEN; in particular, the incidence of fungal infections was low despite the omission of antifungal prophylaxis.