Aims: RAINBOW, a global, placebo-controlled, double-blind, phase III trial, demonstrated significant improvements in overall survival (OS), progression-free survival (PFS), and response rates (ORR) in advanced gastric or GEJ adenocarcinoma patients receiving ramucirumab (RAM), a human IgG1 VEGF receptor 2 targeted antibody, plus paclitaxel (PTX). We present the pre-planned subgroup analysis of Western patients (Region 1). Methods: Pts received RAM (8 mg/kg IV q2w) or placebo (PL) plus PTX (80 mg/m2 d1, 8, 15 of a 4 week cycle) until disease progression, unacceptable toxicity, or until other discontinuation criteria were met. Eligible pts had ECOG PS ≤ 1; and adequate organ function. Randomization was stratified by geographic region (Region 1: Europe, Israel, Australia, and United States, Region 2: Argentina, Brazil, Chile, and Mexico, and Region 3: Asia), time to progression after first dose of first line therapy, and disease measurability. OS and PFS were compared between treatment arms using a stratified log-rank test. ORR was analyzed using a CMH test. Results: Of the 665 randomized patients, 398 (RAM+PTX: 198; PTX: 200) were Western patients. Baseline characteristics were generally balanced between arms. The OS Hazard Ratio (HR) was 0.726 (95% CI 0.580, 0.909; p = 0.0050). Median OS was 8.57m for RAM+PTX and 5.91m for PTX. The HR for PFS was 0.631 (95% CI 0.506, 0.786; p <0.0001). Median PFS was 4.24m and 2.83m. Grade ≥ 3 adverse events (AEs) occurring in >5% of patients on RAM+PTX were: neutropenia, hypertension, leukopenia, fatigue, asthenia, anemia, abdominal pain, and general physical health deterioration. Conclusions: In the Western population of the RAINBOW study, the significant benefits observed in OS, PFS, and ORR were consistent with those in the overall ITT population. The adverse event profile was similar to the overall population.