Real-world evidence of cancer immunotherapy (CIT) combination treatment in first-line (1L) extensive-stage small cell lung cancer (ES-SCLC).

Abstract

8561 Background: Atezolizumab plus chemotherapy was the first CIT combination regimen approved for 1L treatment of ES-SCLC in 2019. This study investigated patient characteristics and treatment patterns for patients with ES-SCLC receiving this regimen in the real-world community oncology setting. Methods: This was a retrospective study including adult patients diagnosed with ES-SCLC between 01-Oct-2018 (after IMpower 133 publication in NEJM Sep-2018) and 31-Dec-2019, with follow-up through 31-March-2020 using The US Oncology Network electronic health records data. Descriptive analyses of patient characteristics and treatment patterns were conducted, with Kaplan-Meier (K-M) methods used to assess time to treatment discontinuation (TTD) and time to next treatment/death (TTNT). Results: Of the 408 patients included in this study, 267 (71.4%) received atezo+carboplatin+etoposide (Atezo+Chemo), 80 (21.4%) received carboplatin+etoposide (Chemo only) and the rest received other regimens. The Atezo+Chemo patients in the real-world cohort compared with the IMpower 133 trial (n = 201) were older (median age 68 vs. 64 years) and included fewer males (45% vs. 64%), fewer white race (73% vs. 81%), more patients with brain metastases at baseline (23% vs. 9%), and more patients with worse ECOG (2/3) performance-status score (24% vs. 0%). The median follow-up, TTD, and TTNT in months (mo) for the real-world cohort are presented in the table alongside the best comparable measures reported for the trial. Conclusions: Most patients in this real-world ES-SCLC cohort received the Atezo+Chemo regimen in the 1L setting. While the follow-up was much shorter and patients had worse baseline characteristics (age, brain metastases, ECOG) in the real-world setting compared to the IMpower 133 trial, the real-world median TTD in this descriptive analysis was found to be in line with the median duration of treatment in the trial. Further research with longer follow-up comparing the real-world effectiveness of the CIT and chemo regimens is needed.[Table: see text]