(B-188) Safety and Effectiveness of Cemiplimab in Combination with Platinum-Doublet Chemotherapy by Demographic Characteristics in First-Line Treatment of Advanced Non-Small Cell Lung Cancer: An Ongoing Real World Evidence Study

Background: The Food and Drug Administration (FDA) has issued guidance urging sponsors to encourage inclusion of underrepresented populations in clinical trials. Non-interventional studies employing real-world (RW) data may be used to evaluate the safety and effectiveness of medicines in populations not well represented in trials. This study seeks to contextualize findings of the EMPOWER-Lung 3 trial for advanced non-small lung cancer (aNSCLC) using RW data in the US for underrepresented populations. Study design, enrollment progress, and patient demographics to date are presented here.

Objectives: This observational study (NCT06269133) will assess the RW safety and effectiveness of first-line (1L) treatment of aNSCLC with cemiplimab in combination with platinum-doublet chemotherapy in underrepresented populations (older patients [≥75 years of age], females, and racial and ethnic minorities) in the US.

Methods: Adult aNSCLC patients without EGFR, ALK and ROS1 aberrations who initiated 1L cemiplimab plus platinum-doublet chemotherapy were identified from two oncology electronic health record (EHR)-based US databases: Flatiron Health ([FH] 11/08/22-02/29/24) and ConcertAI ([CAI] 11/08/22-12/31/23). RW safety endpoints to be assessed are the incidence and severity of any and multiple treatment-emergent immune-mediated adverse events (imAE) and infusion-related reactions. RW effectiveness endpoints to be evaluated include response rate, duration of response, progression-free survival, and overall survival. Patient outcomes will be reported at the end of study enrollment (12/31/26). The sample size target for the study is approximately ≥400 patients.

Results: A total of 340 patients from FH and 123 from CAI met eligibility criteria to date. Across both datasets, most patients are aged < 75 years (71% and 88%) and are male (56% and 57%). Race information is missing for 13% of patients in FH and 1.6% in CAI, while ethnicity is missing for 24% and 21% of patients, respectively. In FH, 85% of patients are White, 11% Black, 2.4% other races, and 1.4% Asian, with 98% being non-Hispanic. In CAI, 85% of patients are White, 9.9% are Black, 4.1% other races, and 0.8% were Asian, with 99% identified as non-Hispanic.

Conclusions: In this study, patients were generally young and male. RW patients treated with cemiplimab primarily consisted of White patients, with smaller proportions of Black patients, other races, and Asian patients. There is also limited representation of Hispanic individuals. These findings are consistent with prior estimates using SEER data on newly diagnosed NSCLC patients. As the study progresses, it is anticipated that uptake in patient subgroups will grow as the adoption of treatment rises over time.