Incidence of infections, cardiac events, neurological toxicity and cytokine response syndrome (CRS) in patients treated with chimeric antigen receptor (CAR) T cell therapy: A 3-year nationwide analysis.

7018 Background: CAR-T cell therapy represents a notable advancement in treating relapsed/refractory (R/R) hematological malignancies. Adverse events include CRS, infections, and neurological and cardiac complications. While there are reports from major academic institutions on the adverse effects of CAR-T therapy, we used data from the National Inpatient Sample (NIS) to gather national estimates of complications related to CAR-T therapy. Methods: A retrospective study was conducted to analyze patients who underwent CAR-T cell therapy by utilizing appropriate ICD-10-PCS procedure codes (XW033C3, XW043C3, XW23346, XW24346, XW23376, and XW24376) from NIS 2019 to 2021. Data regarding infections, toxic encephalopathy (a surrogate for neurological toxicity), and adverse cardiac events were extracted using relevant ICD-10-CM diagnostic codes. Patients experiencing various grades of CRS were identified through specific ICD-10 codes available in 2021 (Grades 1-5: D89.831-D89.835). Results: This study analyzed 6515 patients who underwent CAR-T cell therapy from January 2019 to December 2021. Among them, 60.7% were male. 74.6% were Caucasian, 11.7% were Asian and 6.7% were African American. 49.8% of patients had private insurance, 36.2% had Medicare, and 8.6% had Medicaid. 6.8% of patients were diagnosed with pneumonia, while sepsis occurred in 7.4% of patients and 3% experienced septic shock. 19.4% of patients experienced cardiac arrhythmias, and major cardiovascular events were recorded in 4.7% of the cohort. Acute myocardial infarction and stroke were documented in 0.6 and 1.2% of patients, respectively. Toxic encephalopathy was reported in 19.7% of patients. Among 2235 patients identified to have received CAR-T in 2021, 59.7% developed CRS. Grade 1 and grade 2 CRS were reported in 32% and 21% of patients, respectively, while grade 3 and grade 4 reactions were noted in 4.7% and 2% of patients, with no cases of grade 5 identified. The mean total cost of hospitalization was 308,364$, and the mean length of hospital stay was 19.5 days. The overall in-hospital mortality rate was 3.4%. Conclusions: Our study describes real-world outcomes from a large dataset of CAR-T patients. Infections pose a significant challenge with CAR-T therapy, highlighting the importance of early detection and timely antimicrobial treatment. CRS is common, with a 60% incidence, similar to previous clinical trials (55%). Immediate management is crucial for addressing CRS toxicity. Adverse neurological and cardiovascular incidents are often reported, emphasizing the need for meticulous monitoring and coordinating multidisciplinary care plans. The financial burdens also bear mentioning: CAR-T therapy costs significantly higher than autologous stem cell transplants. Further studies to address these issues are warranted.