Introduction Immune checkpoint inhibitors (ICIs) have become the standard of care in many cancer types. As the number of patients receiving ICIs for various cancers continues to expand, patients and practitioners should be aware of potentially severe immune-related adverse events (irAEs). Despite reports of the incidence of grade 3/4 toxicities, the proportion of patients whose symptoms were clinically severe enough to warrant hospitalization for adverse event management is unknown. Methods This single center, retrospective, observational study was designed to determine the impact of irAEs on patients and the hospital. Patients who started ICIs from May 2016 through May 2019 for melanoma or lung cancer were included. The primary outcome was incidence of hospitalization for irAE. Secondary outcomes included median length of hospitalization, time to onset of irAE, rates of hospitalization for irAE per each checkpoint inhibitor regimen, organ system affected, progression free survival, and overall survival. Results Of 384 patients with melanoma or lung cancer, 27 (7%) were hospitalized at our institution for an irAE. The most common irAE leading to hospitalization was colitis for patients with melanoma and pneumonitis for patients with lung cancer. The median length of stay across all hospitalizations was 10 days. Twenty-five patients required the use of corticosteroids while hospitalized, while eight of these patients required second line irAE treatment. For the total patient population, 34.7% experienced a grade 1/2 irAE and 13.1% experienced a grade 3/4 irAE. Conclusion Our cohort of patients experienced similar rates irAEs as reported in clinical trials and published reports.

e15148 Background: Immune-related adverse events (irAEs) due to immune checkpoint inhibitors (ICIs) are caused by non-specific immune system activation and develop in 30-70% of patients. The goal of this study is to examine the association of race with the development of irAEs secondary to ICIs as autoimmune diseases generally exhibit racial differences. Methods: A retrospective chart review was done using University of Louisville pharmacy database. Patients with solid cancers who received ICIs between Jan 2016 to June 2019 were included. IrAEs were identified through the review of electronic medical records. Descriptive analysis evaluated the incidence and severity of irAEs. Multivariable logistic regression was used to calculate standardized incidence of irAEs among Whites and African Americans. Results: A total of 476 patients were included in this study. The mean age was 61 years, 57% were males and 89.7% were whites. A majority of patients had melanoma (50%). The remainder of the dataset included lung (33.4%), gastrointestinal (7.4%), head & neck (4.8%), breast (2.5%) and genitourinary (1.9%) cancers. ICIs included single agent anti-PD-1 (74.8%), single agent anti-PD-L1 (9.4%), combination anti-CTLA-4 with anti-PD-1 (7.1%). Some patients were also treated with > 1 ICI as subsequent therapy (8.6%). Overall, the rate of irAEs was 44.3% with 33.8% grade 1-2 and 12.4% grade 3-4 irAEs. There was no difference in development of any grade irAEs in Whites as compared to African Americans after adjusting for age, sex, cancer type and ICIs (44.3% vs 44.2%; OR: 0.99, 95% CI: 0.50 – 1.97; p = 0.99). There was also no difference in development of grade 3-4 irAEs in whites as compared to African Americans (12.8% vs 14.5%; OR: 1.16, 95% CI: 0.43 – 3.12; p = 0.75). Conclusions: In this study, we found no racial difference in the development of irAEs between Whites and African Americans. This is in contrast to general autoimmune diseases which exhibit racial differences with higher prevalence among African Americans compared to Whites. We will continue to accrue patients to this study as larger sample size is needed to confirm these findings.

Background Patients who undergo splenectomy are at increased risk of infection caused by encapsulated bacteria. The Advisory Committee on Immunization Practices recommends a series of vaccinations for asplenic patients, the first of which are generally completed prior to hospital discharge in the setting of trauma. However, studies suggest that trauma patients receive booster vaccinations at a suboptimal rate. The aim of this study was to evaluate the impact of an inpatient, pharmacist-led post-splenectomy counseling service on patient understanding and patient-reported revaccination follow-up rate. Methods Patients who underwent splenectomy due to trauma between October 2017 and February 2019 were surveyed via telephone questionnaire at least eight weeks after initial vaccination. Responses were compared to historical data which was collected prior to the service implementation. The primary outcome was patient reported follow-up vaccination rate. Secondary outcomes included patient awareness of vaccine requirements and need for rehospitalization. Results A total of 67 patients met inclusion criteria, of whom 31 (46%) were successfully contacted by phone. After implementation of the post-splenectomy counseling service, 14 patients (45.2%) reported receiving second doses of pneumococcal and meningococcal vaccines, compared to 6 patients (6.3%) in the pre-implementation cohort ( p = 0.000001). Twenty-eight patients (90%) of the patients in the post-implementation cohort acknowledged awareness of the need for additional vaccines, whereas 44 (46%) of patients in the pre-implementation cohort acknowledged awareness ( p = 0.000043). Conclusion A post-splenectomy counseling service led to improved rates of patient reported adherence to booster vaccines, as well as increased awareness for need to revaccinate.