Project Summary: Immune checkpoint inhibitors (ICIs), widely used in cancer treatment, are associated with the development of inflammatory and autoimmune conditions, referred to as immune-related adverse events (irAEs), affecting up to 40-60% of those treated. IrAEs result in additional patient morbidity, decreased quality of life, treatment stoppage, and increased mortality. Furthermore, outcomes in minoritized populations often tend to be worse. Identifying individuals at poorest irAE outcome risk, and the underlying reasons, is critical for pretherapy counseling, tailoring supportive care interventions, and potentially treating with alternate anticancer regimens. Factors known to influence the development of irAEs include increased age, female gender, pre- existing autoimmune disease, ICI targets, genetic factors (HLA-DRB), and pretherapy eosinophil and B cell levels. However, there is limited understanding on the interplay of biologic factors, along with allostatic load and social determinants of health (SDoH), in irAE immunobiology and patient outcomes, and little data on interventions to mitigate irAE impact in minoritized and/or low socioeconomic status (SES) populations. Cutaneous irAEs (ircAEs) provide a unique platform for irAE studies: they are the most common irAEs, are often a precursor to other-organ-specific irAEs, and skin tissue is accessible for study. Thus, I CARE will focus on ircAEs. I CARE will use biologic specimens from the U01 AR077511 (Identification of Pathways to Mitigate Immune- Related Adverse Events with Cancer Immunotherapy; PIs: Leung, Lacouture, Kern) patient cohort, to be diversified with additional enrollees, to further describe the immunobiology of ircAEs (Aim 1), and the association of SDoH, allostatic load, and symptom severity (Aim 2). These data will then be used to inform the implementation of an intensive patient navigation/side effects management intervention, to be tested in a 2-arm pilot randomized controlled trial (versus usual and customary care), for its impact at 6 months on ICI continuation (primary outcome); side effect occurrence, severity, and management; quality of life; and biological changes (secondary outcomes) in a cohort of minoritized and/or low SES cancer patients receiving ICIs (Aim 3). The I CARE study personnel will work with the U54 Linguistic & Cultural Responsiveness Shared Resource and Community Outreach and Research Engagement cores to facilitate participant engagement Relevance: Immune checkpoint inhibitors are immunotherapy drugs that treat various types of cancer, but up to half of patients have adverse events from taking these drugs, with the result that they discontinue the drug early, and may have worse quality of life or even shorter life expectancy. This study investigates whether these adverse events are more likely to happen in patients from minoritized or poorer populations due to increased life stress – and if so, what are the specific factors involved, to address t...