OBJECTIVES: CAR-T cell therapy is an emerging and potentially life-saving final treatment option for patients with treatment-resistant acute lymphocytic leukemia (ALL). However, this therapy does not come without consequences: patients who undergo CAR-T are at risk of major health complications. To identify the risk of complications of CAR-T, this study investigates differences in biochemical lab data among patients treated with CAR-T from those treated with standard chemotherapy.

METHODS: This retrospective cohort study, conducted for the period of 01/01/2021 through 12/31/2022, leveraged Komodo’s Healthcare Map, a claims database that encompasses medical, laboratory, and pharmaceutical encounters of over 330 million patients in the US. These cohorts included patients of all ages and genders with a diagnosis of ALL during the study period (using ICD-10CM codes) and a history of chemotherapy or CAR-T (using NDC, HCPCS, CPT, and ICD10PCS codes). Lab values for bilirubin (mg/dL), hematocrit (percent), and hemoglobin (g/dL) were recorded for each cohort.

RESULTS: 7,789 patients with lab data were diagnosed with ALL within the study period. 46% were treated with chemotherapy and 1.46% with CAR-T. The average levels of bilirubin, hematocrit, and hemoglobin were compared for each treatment cohort with those of all patients with ALL, the baseline cohort. Chemotherapy patients had bilirubin levels that were, on average, 0.41 mg/dL higher than the baseline cohort, hematocrit levels that were 0.77 percentage points lower, and hematocrit levels that were 0.25 g/dL lower. Conversely, bilirubin levels in CAR-T patients were, on average, 1.34 mg/dL higher than the baseline cohort, hematocrit levels that were 1.81 percentage points lower, and hematocrit levels that were 0.62 g/dL lower. All observed differences were statistically significant.

CONCLUSIONS: The magnitude of hematologic differences in ALL patients treated with CAR-T therapy was larger than those treated with chemotherapy. These differences in risk must be considered by patients undergoing such treatments, and their providers.