(196) Real World Comparison of the Efficacy and Safety of Atezolizumab versus Durvalumab in Extensive Stage Small Cell Lung Cancer

Poster Abstract: Background
Small Cell Lung Cancer (SCLC) is an aggressive disease associated with high relapse rates and limited treatment options. Current standard of care treatment for extensive stage disease includes combination chemotherapy plus immunotherapy. Programmed death ligand-1 (PD-L1) targeted immune checkpoint inhibitors are preferred first-line treatments with both atezolizumab and durvalumab being comparable options. Although both medications are listed as front-line options in clinical guidelines, there have been no head-to-head trials comparing durvalumab to atezolizumab. Therefore, it is unknown if either agent is superior with regards to efficacy or toxicity.
Objectives
To assess differences in overall survival between atezolizumab and durvalumab in the treatment of extensive-stage small cell lung cancer. Secondary outcomes include to determine differences in progression free survival, immune related adverse events, ability to be rechallenged with immunotherapy, hospital admissions due to immunotherapy, and to identify any patient populations that may response better to immunotherapy.
Methods
This retrospective, single center chart review study identified patients presenting to Moffitt Cancer Center between October 1st, 2018 to May 31st, 2023 receiving either atezolizumab or durvalumab for extensive-stage small cell lung cancer.
Results
- Pending
Conclusions
- Pending

References (must also be included in final poster): 1. Saida Y, Watanabe S, Kikuchi T. Extensive-stage small-cell lung cancer: current landscape and future prospects. Onco Targets Ther 2023 Aug 2;16:657-671.
2. Gazdar AF, Bunn PA, Minna JD. Small-cell lung cancer: what we know, what we need to know and the path forward. Nat Rev Cancer 2017 Dec;17(12):725-737.
3. Zugazagoitia Z, Paz-Ares L. Extensive-stage small-cell lung cancer: first-line and second-line treatment options. J Clin Oncol 2022 Feb 20;40(6):671-680.
4. Melosky BL, Leighl NB, Dawe D, et al. Canadian consensus recommendations on the management of extensive-stage small-cell lung cancer. Curr Oncol 2023 Jul;30(7):6289-6315.
5. National Comprehensive Cancer Network. (2023). Non-Small Cell Lung Cancer (version 3.2023). https://www.nccn.org/professionals/physician_gls/pdf/nscl.pdf.
6. Mathieu L, Shah S, Pai-Scherf L, et al. FDA approval summary: atezolizumab and durvalumab in combination with plantium-based chemotherapy in extensive stage small cell lung cancer. The Oncologist May 2021;26(5):433-438.
7. Horn L, Mansfield AS, Szczęsna A, et al. First-line atezolizumab plus chemotherapy in extensive-stage small-cell lung cancer. N Engl J Med 2018(379):2220-2229.
8. Paz-Ares L, Dvorkin M, Chen Y, et al. Durvalumab plus platinum–etoposide versus platinum–etoposide in first-line treatment of extensive-stage small-cell lung cancer (CASPIAN): A randomised, controlled, open-label, phase 3 trial. Lancet 2019;394(10212):1929-1939.
9. Chen J, Wang J, Xu H. Comparison of atezolizumab, durvalumab, pembrolizumab, and nivolumab as first-line treatment in patients with extensive stage small cell lung cancer. A systemic review and network meta-analysis. Medicine 2021;100:15(e25180).
10. Zou Y, Ren X, Zhang H, et al. Efficacy and safety of durvalumab + chemotherapy vs. atezolizumab + chemotherapy in the treatment of small-cell lung cancer: a retrospective comparative cohort study. J Thorac Dis. Jun 30 2023;15(6):3339-33349.