LAUSR

614 Background: Axitinib (axi) is approved for 2nd-line treatment of aRCC. In AXIS trial, median progression-free survival (PFS) was significantly longer in axi- vs sorafenib (sor)-treated pts (hazard ratio [HR] 0.67, 95% CI 0.54–0.81, P<0.0001). Association between mRNA/miRNA expression and clinical outcomes in a subset of axi- or sor-treated pts from AXIS was assessed. Methods: mRNA/miRNA analyses were performed on archival tumor samples. Expression was summarized for responders (complete and partial response) vs non-responders (stable and progressive disease), and for maximum percent tumor change. PFS and overall survival (OS) were analyzed by Kaplan-Meier. Results: Pt characteristics were similar between axi (n=34) and sor (n=33) arms. Association with outcomes is shown in the Table. A correlation was observed for CD68 protein and mRNA expression in axi-treated pts (R=0.4774 P=0.0043 and R=0.3985 P=0.0196, respectively). Both CXCR4 and TLR3 showed differences between treatment arms and association with PFS. TNFSF10