Ty, MD2, Yinghong Wang, MD, PhD1 1 MD Anderson Cancer Center, Houston, TX, USA; 2Georgetown University, Washington, DC, USA Correspondence: Yinghong Wang ([email protected]) Journal for ImmunoTherapy of Cancer 2018, 6(Suppl 1):P538 Background CYP26 web immune checkpoint inhibitor (ICPI), which is an efficacious treatment for sophisticated malignancies, is normally restricted by immune mediated diarrhea and Macrophage migration inhibitory factor (MIF) Inhibitor Purity & Documentation colitis (IMDC). Steroids and infliximab are usually made use of to treat extreme IMDC given its immune mediated mechanism. These agents induce systemic immunosuppression with its associated morbidity. Additionally, systemic immunosuppression could possibly hamper the effect of ICPI. Hence, we aimed to assess clinical outcomes of vedolizumab (a gut-targeted anti-integrin agent) as an option treatment for IMDC. Techniques This can be a retrospective multicenter case series of adult individuals who had IMDC and received vedolizumab from 12/2016 through 4/2018 from MD Anderson Cancer Center and Medstar-Georgetown University. All patients had IMDC that’s refractory to steroids and/or infliximab. Outcomes Twenty-eight patients were incorporated; 20 males (71), 25 Caucasians (89) having a mean age of 63 years (Table 1). One of the most popular malignancy was melanoma in 7 patients (25). Eight sufferers (29) received anti-cytotoxic T- lymphocyte associated antigen-4 (CTLA-4), 12 (43) programmed death protein-1 or its ligand (PD-1/L-1) and eight (29) mixture therapy. Median time from ICPI to IMDC onset was 10 weeks (IQR 1-70). Fifteen patients (54) had grade 2 and 13 (46) had grade 3 or 4 IMDC. Diagnostic evaluations for IMDC are shown in (Table 2). The median reduction in fecal calprotectin values was 347 for vedolizumab initiation 14 days of IMDC onset and 197 for 14 days (Figure 1). Mucosal ulceration was present in eight patients (29), whereas nonulcerative inflammation was present 13 (46). All of our individuals had capabilities of active histological inflammation; 14 (50) had concurrent capabilities of chronicity, and ten (36) had options of microscopic colitis. The treatment and outcomes of IMDC are shown in (Table three). Imply duration of steroid remedy was 96 days (SD 74). Seven patients received infliximab as well as steroids and had been refractory to it. Median variety of vedolizumab infusions was 3 (IQR 1- four). Imply duration of follow-up was 15 months. Twenty 4 individuals (86) achieved and sustained clinical remission. Repeat endoscopic evaluation was performed in 17 individuals. Endoscopic remission was attained in 7 (54) in the 13 individuals who had abnormal endoscopic findings initially with 5/ 17 (29) individuals reaching histological remission as well. (Table 4) lists the characteristics of sufferers who had clinical remission. In our cohort, 1 patient developed skin rash and 1 had joint pain. Conclusions Vedolizumab might be an suitable therapy for steroid refractory IMDC, with favorable outcomes and great security profile. Ethics Approval This retrospective, single-center study was approved by the Institutional Critique Board in the University of Texas MD Anderson Cancer Center (IRB No. PA18-0472). Consent This study was granted waiver for consent.Fig. 1 (abstract P537). Kaplan-Meier overall survival curve stratified by immune checkpoint inhibitor (ICPI)-induced diarrhea/colitis statusFig. 2 (abstract P537). Kaplan-Meier progression-free survival curve stratified by immune checkpoint inhibitor (ICPI)-induced diarrhea/colitis statusFig. three (abstract P537). Kaplan-Meier overall survival curve stratified.