Effect of concurrent beta-blocker use in patients receiving immune checkpoint inhibitors for advanced solid tumors.

Abstract

e15068 Background: Stress-induced adrenergic signaling suppresses the immune system. In animal model systems, pharmacological beta-blockade stimulated CD8+ T-cell activity, and further, it improved clinical activity of immune checkpoint inhibitors (ICI) in inhibiting tumor growth. Herein, we investigate the effect of beta blockers (BB) on clinical outcomes of patients receiving ICI in advanced solid tumors. Methods: We retrospectively evaluated patients with solid tumors treated with at least 2 doses of ICI at our institution from December 2010 to April 2017. The primary outcome was disease control rate (DCR), as defined by radiographic complete response, partial response, or stable disease, by RECIST 1.1 criteria. The primary predictor was use of BB (β1-selective BB vs. no BB; non-selective BB vs no BB). The primary predictive variable was analyzed using multivariate logistic regression model controlling for several parameters including patient demographics, co-morbidities, ECOG performance status, and tumor type and location of metastases. All tests were two-sided at the significant level of 0.05. Results: We identified 298 evaluable patients with median age of 66.5 (31-95). Of these patients, 200 (67%) did not use BB, 75 (25%) used β1-selective BB, and 23 (8%) used non-selective BB. In multivariate analysis, use of β1-selective BB was significantly associated with improved DCR compared to no BB (ORR 2.43, 95% CI 1.31-4.51, P = 0.005), while use of non-selective BB was not associated with improved DCR (ORR 1.71, 95% CI 0.65-1.47, P = 0.27). Conclusions: The concurrent use of BB may enhance the clinical activity of ICI, particularly β1-selective BB. Our findings warrant further investigation to understand the interaction of β1- and β2-adrenergic signaling and antitumor immune activity, and potentially explore a combination strategy of ICI and BB.