Oncologic outcomes following biologic therapy for immune-related cutaneous adverse events.

12156 Background: Biologic agents are increasingly used to treat immune-related cutaneous adverse events (ircAEs). However, limited data exist regarding immune checkpoint inhibitor (ICI) rechallenge and ICI efficacy following biologic therapy for ircAE management. Methods: We conducted a retrospective cohort study of patients enrolled under U01AR077511-01 (PIs Leung, Kern, Lacouture) treated with ICIs who developed dermatologist-confirmed grade ≥2 ircAEs. Demographics, ircAE treatments, and dermatologic and oncologic outcomes were collected via chart review and compared using t-tests and chi-square tests. Results: We identified 159 patients who developed grade ≥2 ircAEs, including 80 treated with biologic agents. Mean age was 66.8 years; 40% were female, 79% White, and 78% had stage IV disease. The most common tumor types were kidney (20%), lung (16%), and melanoma (12%). Common ICI regimens included ICI monotherapy (46%), ICI–ICI combination (21%), and ICI+chemotherapy (19%). Pruritus (23%), maculopapular rash (21%), and eczema (19%) were the most common ircAEs. Most patients received topical steroids (88%), while systemic steroids were used sparsely (13%). Biologics were used in ~50% of patients; the most common agents were dupilumab (43%), omalizumab (33%), and ustekinumab (11%). Median biologic duration was 16 weeks, with 25% receiving therapy for >40 weeks. ICI rechallenge occurred in 60% of biologic-treated versus 67% of non-biologic patients (p=0.35). Rechallenge rates were 67% vs 65% for grade 2 (p=0.85) and 44% vs 74% for grade 3 ircAEs (p=0.05) (biologic vs non-biologic, respectively). Antitumor outcomes were similar between biologics and non-biologic groups: 31% vs 28% achieved partial/complete response, 43% had stable disease, and 26% vs 29% had progressive disease, respectively. Conclusions: In this oncodermatology-managed cohort, ircAEs were primarily treated with topical corticosteroids and targeted biologics, with infrequent systemic steroid use. Biologic therapy enabled ICI rechallenge in most patients, and oncologic outcomes were comparable to those not receiving biologics. Overall, these findings support biologics as a steroid-sparing option for moderate-to-severe ircAEs that may allow continued immunotherapy without apparent loss of antitumor efficacy, warranting prospective validation. Clinical characteristics. Variable Overall n=159 No Biologics n=79 Biologics n=80 Age at ICI (mean) 66.8 64.3 69.4 Tumor Types Kidney/Lung/Melanoma (%) 20/16/12 22/17/9 18/15/15 Line of treatment 1L/2L/2+L (%) 52/25/23 49/27/24 54/24/22 ircAEs: Pruritus/MPR/Eczema/Others (%) 23/21/19/37 22/33/17/28 25/9/21/45 ircAE Grade 2/Grade 3 (%) 74/26 76/24 71/29 Dupilumab/Omalizumab/Ustekinumab/Others (%) 33/33/11/23 N/A 33/33/11/23 Systemic Steroids - Yes (%) 13 8 18 ICI Rechallenge - Yes (%) 64 67 60 Response CR-PR/SD/PD (%) 30/43/27 31/43/26 28/43/29