O2-1-2A multicenter retrospective study of Paclitaxel vs. Paclitaxel plus Ramucirumab for advanced gastric cancer patients

Abstract Background Ramucirumab (RAM) conferred survival benefit in patients with advanced gastric cancer (AGC) in the RAINBOW trial (HR 0.807, 95% CI: 0.678-0.962, p = 0.017). However, in the Japanese subpopulation, adding RAM showed modest overall survival (OS) benefit compared with patients in Western country (HR 0.88 vs. 0.73). The objective of this retrospective study was to clarify additional benefit of RAM in clinical practice for Japanese patients. Method We reviewed medical records of AGC patients who were treated with Paclitaxel (PTX) or PTX+RAM between Jan 2014 and Dec 2016 as second-line treatment in 9 Japanese institutions, excluding patients with prior use of taxane or RAM. Result A total of 154 patients were included (63 in PTX and 91 in PTX+RAM). Patient characteristics of PTX vs. PTX+RAM groups were: age (median) 64 vs. 64, male 67% vs. 75%, PS (0/1/2) 27/63/10% vs. 30/67/3%, disease status (metastatic/recurrent) 75/25% vs. 63/37%, histology (intestinal/diffuse/other) 24/57/19% vs. 31/44/25%, number of metastatic sites (0-2/≥3) 75/25% vs. 70/30%, ascites (+/-) 54/46% vs. 50/50%, and platinum combined with fluoropyrimidine in the first line (oxaliplatin/cisplatin) 16/84% vs. 37/63%. The median OS in the PTX vs. PTX+RAM groups were 7.0 vs. 9.3 months (HR 0.73, 95% CI: 0.52-1.04, p = 0.083). The median PFS were 3.2 vs. 4.1 months (HR 0.66, 95% CI: 0.47-0.93, p = 0.016). Among 39/55 patients who had measurable lesions, response rate and disease control rate were 18% vs. 35% and 56% vs. 76%, respectively. The proportion of patients receiving subsequent treatment was 57% in PTX group and 59% in PTX+RAM group. Grade 3 or more adverse events were observed more frequently in PTX+RAM group, including neutropenia (55% vs. 21%) and leucopenia (31% vs. 19%) than PTX group. Conclusion Although this study was retrospective investigation with small sample size, adding RAM to PTX conferred clinically meaningful efficacy and safety in clinical practice for Japanese patients.