Checkpoint inhibition in immunosuppressed or immunocompromised patients with advanced cutaneous squamous cell carcinoma (CSCC): Data from prospective CemiplimAb-rwlc Survivorship and Epidemiology (C.A.S.E.) study.

Abstract

9547 Background: Immunosuppressed and/or immunocompromised patients are at increased risk for solid tumors and cutaneous malignancies. Limited data exist on the safety and effectiveness of immune checkpoint inhibitors (ICIs) in these patients because they are frequently excluded from clinical trials. Here, we describe the safety and effectiveness results from the initial cohort of immunosuppressed and/or immunocompromised patients with advanced CSCC enrolled in the C.A.S.E. study (NCT03836105). Methods: C.A.S.E. is a prospective, real-world, multi-center, longitudinal study evaluating the effectiveness, safety, quality of life, and survivorship in patients with advanced CSCC treated with cemiplimab. Patients received cemiplimab 350 mg intravenously every 3 weeks per routine standard of care. Patient demographics, disease characteristics, immunosuppression, and relevant medical history were collected. Immunosuppressive regimens varied amongst patients. Investigator assessment of objective response rate (ORR), safety, and tolerability was conducted. Data from 26 immunosuppressed and/or immunocompromised patients with advanced CSCC treated with cemiplimab are presented. Recruitment is ongoing. Results: As of November 17, 2020, 121 patients were enrolled in the C.A.S.E. study, of which 26 patients (median age: 74 years [IQR: 71-84]; 85% male; 89% Caucasian) were designated as immunocompromised or immunosuppressed due to a history of solid organ transplant (n = 6), autoimmune disorder (n = 11), or hematologic malignancy (n = 9). Median duration of cemiplimab exposure was 14 months (IQR: 9.1–42, range: 0, 67). Among 19 immunocompromised or immunosuppressed patients who enrolled in C.A.S.E. prior to their third dose of cemiplimab, ORR per investigator assessment was 47% (95% CI: 24–71); 1 (5%) patient had complete response; 8 (42%) had partial response. One patient had a treatment-related serious adverse reaction of organ transplant rejection. One (3.8%) patient discontinued treatment due to increased alanine aminotransferase (not treatment-related). Immune-related AEs (irAEs) occurred in 23% of patients. No treatment-related AEs led to death. Conclusions: The safety, tolerability, and effectiveness of cemiplimab in this initial cohort of immunosuppressed and/or immunocompromised patients with advanced CSCC appear to be consistent with those observed in clinical trials that excluded these patients. Further follow-up and additional data would add to our general understanding of safety and effectiveness of anti-PD1 therapy in immunocompromised and/or immunosuppressed patient populations overall. Clinical trial information: NCT03836105.