Abstract 28: Identification of multisite real-world patient cohorts to enable immunotherapy utilization and safety assessment
Authors: Del Vecchio Fitz Catherine , Eldridge Elizabeth , Antonopoulos Alyssa , Petrone Paula , Caldwell Will , Corbett Ed , Flaster Amy , Rimmasch Holly , Albayrak Adem , Sanders Dale , Mahmood Sadiqa , Stupka Elia 
Published: August 2020

Abstract
Currently, five classes of Immunotherapy (IT) agents are available for over 20 cancer types, including a powerful new class utilizing T cells genetically engineered to express a chimeric antigen receptor (CAR-T). Additional classes include bi-specific T-cell engagers (BiTEs), immune checkpoint inhibitors (ICIs), cancer vaccines, and oncolytic viruses. Despite promising antitumor activity, significant immune-related adverse events (irAE) have been reported. The most common CAR-T toxicity is cytokine release syndrome (CRS), and management typically includes supportive care and immunosuppression with corticosteroids or the IL-6 inhibitor tocilizumab. Documented CRS and tocilizumab use outside of CAR-T is rare, but recent evidence suggests that tocilizumab is emerging for management of other steroid-refractory irAE. Given the rapid evolution of this field, there remains a need to understand the utilization of IT and the pathophysiology of irAE in real-world settings. To identify cohorts of interest, a retrospective, multicenter review was conducted using Health Catalyst’s extended real-world data database, Touchstone, which includes &gt;300 sources of data and over 70 multipayer and geographically diverse provider clients. Cohorts were selected from representative provider networks, including large and specialty academic medical centers (AMCs), integrated delivery networks, accountable care organizations, and community hospitals in the US. A total of 10 clients’ de-identified electronic medical records were searched for presence of cancer-associated diagnosis codes. The cohort was then restricted by the presence of medication order or administration of any IT-class drug, and among these, first administration of tocilizumab within 21 days. Across ten provider networks containing data for ~5.6 million cancer patients, 9,029 patients were identified: CAR-T, 116 patients (0-102); BiTEs, 112 patients (0-64); ICIs, 8,402 patients (0-4520); cancer vaccines, 182 patients (0-143); and oncolytic viruses, 217 patients (0-214). As expected, CAR-T administration was limited to approved treatment centers. Among the other classes, an average of 26% of identified patients were from the community setting. Additionally, of the 116 patients receiving CAR-T therapy, 75 patients (64.7%) were administered tocilizumab within 21 days. Evidence of tocilizumab use outside of CAR-T irAE was also identified, occurring in 21 patients (0.3%) receiving another class of IT within AMCs, and did not occur at other provider types. Together this analysis identified several real-world IT patient cohorts comprising diverse populations from a range of provider types, with corresponding access to rich patient-level clinical, molecular, and financial real-world data (RWD) elements. Immediate downstream applications will involve developing integrated methods for the real-time identification of patients who may be at risk for adverse events and standardization of toxicity management guidelines.
Citation Format: Catherine Del Vecchio Fitz, Elizabeth Eldridge, Alyssa Antonopoulos, Paula Petrone, Will Caldwell, Ed Corbett, Amy Flaster, Holly Rimmasch, Adem Albayrak, Dale Sanders, Sadiqa Mahmood, Elia Stupka. Identification of multisite real-world patient cohorts to enable immunotherapy utilization and safety assessment [abstract]. In: Proceedings of the AACR Special Conference on Advancing Precision Medicine Drug Development: Incorporation of Real-World Data and Other Novel Strategies; Jan 9-12, 2020; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(12_Suppl_1):Abstract nr 28.