LAUSR

104Background: BMS-986156 is a fully human IgG1 agonist mAb that binds GITR and promotes T effector cell activation and possible reduction/inactivation of T regulatory cells. Preclinical data show enhanced antitumor T-cell activity with anti-GITR + anti–programmed death-1 (PD-1). Here we describe preliminary dose escalation data from a phase I/IIa study of BMS-986156 ± nivolumab (anti–PD-1 mAb) in pts with advanced solid tumors (NCT02598960). Methods: During dose escalation, pts received BMS-986156 (10–800 mg) or BMS-986156 (30–800 mg) + nivolumab (240 mg) every 2 weeks. Objectives included safety (primary), immunogenicity, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy. Results: As of Dec 12, 2016, 66 pts were treated with BMS-986156 (n = 29) or BMS-986156 + nivolumab (n = 37).No dose-limiting toxicities (DLTs) were reported during dose escalation. The most common treatment-related adverse events reported with BMS-986156/BMS-986156 + nivolumab included pyrexia (21%/30%), chills (10%/16%), and...