Journal of Clinical Oncology | 2019
Exploratory evaluation of baseline tumor biomarkers and their association with response and survival in patients with previously treated advanced gastric cancer treated with andecaliximab combined with nivolumab versus nivolumab.
Abstract
148Background: Andecaliximab (ADX) is a monoclonal antibody that inhibits matrix metalloproteinase 9 (MMP9). Preclinical studies suggest that MMP9 inhibition relieves immune suppression and promotes T cell infiltration to potentiate checkpoint blockade. In the phase 2 study combining ADX with nivolumab (N) versus N monotherapy (NCT02864381), addition of ADX to N did not improve objective response rate, progression-free survival (PFS), or overall survival (OS). Methods: Archival tumor samples were collected from all patients (n = 141). CD8 and PD-L1 (28-8 DAKO) were assessed by immunohistochemistry. CD8+ cell density was measured in the tumor area. PD-L1 was prospectively scored by a pathologist for tumor cell (TC) and associated immune cell (IC) positivity. IFNg, Teffector (Teff), and activated CD8+ T cell (ActT) gene signatures were assessed by RNA sequencing. Due to a small number of responders, treatment arms were combined to evaluate response. Cox proportional hazards models were used for survival ana...