3049 Background: Owing to its high efficacy and tolerability, brentuximab vedotin (BV) is increasingly being favored over other aggressive systemic therapies for the treatment of various CD30+ Hodgkin and non-Hodgkin lymphomas, including peripheral T-cell lymphoma and cutaneous T-cell lymphomas. Dermatologic adverse events (dAE) are one of the most common toxicities associated with BV but data regarding their characteristics including correlation to dose, time to occurrence, and management is scarce. We aim to describe the clinical and pathologic characteristics of dAEs associated with BV, their relationship with administered dose regimen, and available management strategies. Methods: An IRB-approved retrospective analysis was conducted for all patients who had received at least one cycle of BV from Memorial Sloan Kettering Cancer Center in 2009-2020. Logistic regression, χ2, student’s t-test were performed for univariate analyses. Kaplan-Meier survival and multivariate Cox proportional hazard model evaluated dAE occurrence stratified by 5 major dose regimens (single cycle, 1.2mg q1w, 1.2mg q2w, 1.2mg q3w, 1.8mg q3w). Results: Of 611 patients, 201 experienced dAE with median time-to-event of 24 days and 29% experiencing > 1 dAEs. Rash was the most common (62%; 142/230), followed by alopecia (20%) and xerosis (13%). For rash, 50% reported involvement of only the extremities and/or acral sites compared to 25% who had generalized rash. Of those reported (111), 68 patients had grade 1 dAE (61%), 38 grade 2 (34%), and 5 grade 3 (5%)-all grade 3 were rash (maculopapular/morbilliform). 14 cases (7%) resulted in treatment interruptions and 6 in discontinuations due to dAEs (3%). Pathology were often nonspecific consistent with a hypersensitivity reaction: spongiotic/psoriasiform dermatitis with perivascular lymphocytic infiltrates . Patients undergoing weekly regimen were at a statistically and clinically significantly higher risk of dAE during the first 100 days of BV treatment (p = 0.001). Between the two most frequently administered dose regimens (1.8mg vs. 1.2mg, q3w), the higher dose carried 105% higher risk for dAE (HR: 2.047, p = 0.053). Those who had received a single cycle of BV had the lowest risk compared to all other regimen (1/42, p = 0.001). Topical and/or systemic steroids were most frequently prescribed (43%) with 12% of patients requiring systemic steroids. Other treatments varied ranging from antihistamines to moisturizers. Conclusions: Understanding of the detailed characteristics, management strategies, dose-dependent effects associated with BV is critical to provide clinical guidance for primary providers and minimize treatment interruptions or discontinuations. The results overall suggest that the risk for dAEs is dose-dependent with those undergoing frequent dosing regimens having a greater risk, although most dAEs remain mild or low-grade.