Inpatient outcomes of blinatumomab use: A national inpatient sample analysis.

e19021 Background: Blinatumomab, a bispecific (CD3/CD19) T-cell engager, is indicated for the treatment of acute lymphoblastic leukemia (ALL). The initial portion of each cycle is administered in the inpatient setting for close monitoring for cytokine release syndrome and neurotoxicity. Real world data are lacking on the cost of hospitalization, length of stay (LOS), and mortality in inpatients treated with blinatumomab. The goal of this study was to analyze the clinical outcomes of inpatient blinatumomab administration utilizing a national database. Methods: The ICD-10 diagnosis and procedure codes were used to identify Blinatumomab admissions and related complications from the 2018 version of the Nationwide Inpatient Sample (NIS) database from the Healthcare Cost and Utilization Project (HCUP). Weighted analysis was used to calculate national estimates. Logistic regression analyses were used to examine predictors of hospital outcomes (in-hospital mortality, length of stay, and cost), with p < 0.05 considered statistically significant. Data were analyzed using SAS v9.4 (SAS Institute, Cary, NC). Results: A total of 228 patients received inpatient blinatumomab in this cohort. Median age was 46 years old (IQR 26.8, 63.0) and 59.2% were males, 50.4% were white, and 47.4% had private insurance. The majority of patients received care at an urban teaching (96.1%) or large hospital (76.3%). The most relevant inpatient complications during hospitalization included hypotension (7.5%), pneumonia (6.1%), sepsis (9.2%), seizure (2.2%), neutropenia (6.1%), thrombocytopenia (14.0), tumor lysis syndrome (3.9%), and acute kidney injury (9.6%). Median LOS was 9.0 days (IQR 3.0-16.2) and median hospitalization charge was $114,936 USD (IQR 51,984.2-240,557.5). On multivariate regression analysis, dialysis (OR 1.67, 95% CI 1.05-2.65), blood product transfusion (OR 1.5, 95% CI 1.14-1.97), sepsis (OR 2.63, 95% CI 1.86-3.73), neutropenia (OR 1.86, 95% CI 1.23-2.81), and pancreatitis (OR 1.46, 95% CI 1.11-1.91) were all associated with longer LOS. Dialysis (OR 1.83, 95% CI 1.29-2.6), transfusions (OR 1.52, 95% CI 1.01-2.28), sepsis (OR 1.87, 95% CI 1.20-2.91) and neutropenia (OR 1.84, 95% 1.04-3.24) significantly increased the cost of hospitalization. Conclusions: In this cross-sectional study of a large national cohort of patients receiving inpatient blinatumomab, multiple blinatumomab associated toxicities led to increased LOS and cost of hospitalization.