CemiplimAb-rwlc Survivorship and Epidemiology (CASE): A prospective study of the safety and efficacy of cemiplimab in patients (pts) with advanced cutaneous squamous cell carcinoma (CSCC) in a real-world setting

Cemiplimab is the first programmed cell death-1 inhibitor approved for the treatment of pts with locally advanced or metastatic CSCC who are not candidates for curative surgery or curative radiation. Here, we describe demographics, effectiveness, and safety results of cemiplimab in a general population of pts with advanced CSCC enrolled in the CASE study (NCT03836105). CASE is a real-world study evaluating the effectiveness, safety, disease evolution, survivorship, and quality of life of pts with advanced CSCC treated in 43 US academic and community centres. Pts had received cemiplimab 350 mg intravenously every 3 weeks per standard of care. Prospective data are captured using an electronic case report form and include demographics, disease characteristics, efficacy, and quality-of-life data. Investigator assessment of objective response rate (ORR), survival, and safety was conducted. Data collected between June 2019 and October 2021 are presented. Recruitment is ongoing. As of 1 Oct 2021, 188 pts were enrolled in the CASE study. Median age was 76.0 years (range, 33.0–98.0), 76.9% were male, 90.9% were White, and 36 (19.1%) were considered immunocompromised or immunosuppressed (IC/IS). Median duration of cemiplimab exposure for all pts was 22.1 weeks (quartile [Q] 1–Q3, 9.1–46.4; range, 0–117). Efficacy was evaluated in pts enrolled before Cycle 3 (n=164), when a clear treatment outcome could be established. ORR for the overall population was 42.1% (95% confidence interval [CI], 34.4–50.0) and for the IC/IS population (n=27) was 44.4% (95% CI, 25.5–64.7). Eight (4.3%) pts experienced a treatment-related serious adverse event and 47 (25.3%) experienced a treatment-related immune-related adverse event. Cemiplimab was generally well tolerated in IC/IS pts. In total, 95 (48.2%) pts discontinued treatment. At this timepoint, the safety, tolerability, and effectiveness of cemiplimab in this real-world study of pts with advanced CSCC were consistent with results observed in the registration clinical trial (NCT02383212, NCT02760498).