Background: It is unclear whether prior treatment with ramucirumab (RAM) or RAM plus paclitaxel (PAC), standard second-line treatments for metastatic gastric or gastroesophageal junction cancer (mGC/GEJC), can influence outcomes with third-line chemotherapy in this patient (pt) population (pop). In the phase 3 TAGS trial, FTD/TPI showed a survival benefit vs placebo (PBO) in pts with mGC/GEJC who had received ≥2 prior chemotherapy regimens. Post hoc analyses were performed to assess the impact of prior RAM, PAC or RAM+PAC treatment on the efficacy and safety of FTD/TPI in TAGS. Methods: Pts in the TAGS trial were categorized into 5 subgroups based on prior treatment received as follows: A) RAM (alone or combined with other agents), B) no RAM, C) PAC (but no RAM), D) RAM+PAC (sequentially or in combination) and E) neither PAC nor RAM. While subgroups A and B were prespecified, all other subgroups were identified post hoc. Efficacy (overall survival [OS] and progression-free survival [PFS]) and safety were assessed in these subgroups. Results: In the overall pop (N=507), 33% had received prior RAM (alone/combined); 30% prior RAM+PAC; 27% prior PAC but no RAM; and 40% had received neither PAC nor RAM. As only 3% of all pts received prior RAM but no PAC, that subgroup was not considered in this analysis. FTD/TPI treatment was consistently associated with benefits in OS and PFS vs placebo across all pt subgroups (Table). Among pts randomized to FTD/TPI, OS benefit was similar between pts who received RAM+PAC vs those who received neither (HR, 1.15; 95% CI, 0.84–1.58) and between pts who received PAC (but no RAM) vs those who received neither (HR, 0.91; 95% CI, 0.66–1.25). The FTD/TPI safety profile was consistent across all subgroups, with similar overall incidences of grade ≥3 adverse events (AEs). Minor variations in hematologic toxicities were noted (Table). Conclusions: In the phase 3 TAGS trial, FTD/TPI treatment in the third or later line provided efficacy benefits vs PBO and demonstrated a consistent safety profile in pts with mGC/GEJC regardless of prior treatments. Clinical trial information: NCT02500043

^aSlightly different source parameters accounted for minor variations in pt numbers.

Taiho Oncology, Inc.