Abstract
Immune checkpoint inhibitors (ICI) target the PD-1/PD-L1 and CTLA-4 pathways and allows the immune system to deliver antitumor effects. However, it is also associated with well-documented immune-related cutaneous adverse events (ircAEs), affecting up to 70-90% of patients on ICI. In this study, we describe the characteristics of and patient outcomes with ICI-associated steroid-refractory or steroid-dependent ircAEs treated with dupilumab. Patients with ircAEs treated with dupilumab between March 28, 2017, and October 1, 2021, at Memorial Sloan Kettering Cancer Center were included in this retrospective study, which assessed the rate of clinical response of the ircAE to dupilumab and any associated adverse events (AEs). Laboratory values were compared before and after dupilumab. All available biopsies of the ircAEs were reviewed by a dermatopathologist. Thirty-four of 39 patients (87%, 95% CI: 73% to 96%) responded to dupilumab. Among these 34 responders, 15 (44.1%) were complete responders with total ircAE resolution and 19 (55.9%) were partial responders with significant clinical improvement or reduction in severity. Only 1 patient (2.6%) discontinued therapy due to AEs, specifically, injection site reaction. Average eosinophil counts decreased by 0.2 K/mcL (p=0.0086). Relative eosinophils decreased by a mean of 2.6% (p=0.0152). Total serum immunoglobulin E levels decreased by an average of 372.1 kU/L (p=0.0728). The most common primary inflammatory patterns identified on histopathological examination were spongiotic dermatitis (n=13, 33.3%) and interface dermatitis (n=5, 12.8%). Dupilumab is a promising option for steroid-refractory or steroid-dependent immune-related cutaneous adverse events, particularly those that are eczematous, maculopapular, or pruritic. Among this cohort, dupilumab was well-tolerated with a high overall response rate. Nonetheless, prospective, randomized, controlled trials are warranted to confirm these observations and confirm its long-term safety.