Association Of Efficacy Of Anti-Pd-1 Immunotherapy In Patients With Advanced Cancer With Immune-Related Adverse Events (Iraes)

e14064 Background: Cancer immune therapy has shown benefit in many cancer types, although it may initiate autoimmune-related disorders in some patients. We have attempted to establish whether the incidence of irAEs after the use of nivolumab or pembrolizumab in advanced malignancies is associated with anti-PD-1 treatment efficacy. Methods: We retrospectively reviewed all clinical records of patients treated with single-agent nivolumab or pembrolizumab for advanced cancer from january 2016 until september 2018. IrAEs were identified clinically and graded as per the CTCAE v.4.0. Efficacy was evaluated with objective response rate (ORR, iRECIST criteria), progression-free survival (PFS) and overall survival (OS). Uni and multivariate tests were performed to determine the association between irAEs and ORR, PFS or OS. Results: We identified 110 patients. Primary diagnoses were lung cancer (n = 78), melanoma (n = 10), head and neck carcinoma (n = 7), renal carcinoma (n = 5), Hodgkin's lymphoma (n = 3), urothelial carcinoma (n = 3) and gallbladder adenocarcinoma, hepatocellular carcinoma, gastric adenocarcinoma and Merkel cell carcinoma (n = 1 each). IrAEs were observed in 40 patients (36.4%). The most frequent irAEs were hypothyroidism (n = 15), nephritis (n = 5) and hyperthyroidism (n = 4). Objective response was observed in 45 patients (40.9%), median PFS was 5 months (0.5-32 months) and median overall survival was 24.5 months (3-110 months). Thirty-three of the 40 patients with irAEs had objective response (82.5%) in contrast with 12 of the 70 cases without irAEs (17%) (OR 22.78, 95% CI 5.9-87.0, P < 0.000001). PFS in patients with irAEs was 10 months and 3 months in those without irAEs (HR 2.4, P = 0.004). OS in patients with irAEs was 32 months and 22 in those without irAEs, without statistically significant differences. Conclusions: In advanced cancer treated with nivolumab or pembrolizumab, patients who developed irAEs showed a significantly improved efficacy (ORR of 82.5% and PFS of 10 months) over patients without irAEs (ORR of 17% and PFS of 3 months).