Trifluridine/tipiracil in patients with metastatic gastroesophageal junction cancer: a subgroup analysis from the phase 3 TAGS study

BACKGROUND: Patients with advanced gastroesophageal junction cancer (GEJC) have poor survival outcomes, and GEJC-specific data from trials evaluating agents in gastric cancers (GCs) as a whole are lacking. Trifluridine/tipiracil (FTD/TPI) was approved for previously treated metastatic GC or GEJC (mGC/mGEJC) based on results of the phase 3 TAGS trial. Subgroup analyses by primary tumor type (GC or GEJC) in TAGS are reported here. METHODS: Pa tients with mGC/mGEJC treated with ≥ 2 prior chemotherapy regimens were randomized (2:1) to receive FTD/TPI or placebo, plus best supportive care. A pre-planned sub-analysis was performed to evaluate efficacy and safety outcomes by primary tumor type (GEJC or GC). RESULTS: Of 507 randomized patients, 145 (29%) had GEJC and 360 (71%) had GC as the primary disease site. Baseline characteristics were generally similar between the GEJC and GC subgroups, except that more patients in the GEJC subgroup had received ≥ 3 prior regimens (72 vs. 59% in the GC subgroup). Survival benefit with FTD/TPI was observed in both subgroups. The overall survival hazard ratio for FTD/TPI vs placebo was 0.75 (95% CI 0.50–1.11) and 0.67 (95% CI 0.52–0.87) in the GEJC and GC subgroups, respectively. Grade ≥ 3 adverse events of any cause were reported in 75 (77%) and 192 (81%) FTD/TPI-treated patients in the GEJC and GC subgroups, respectively. No new safety concerns were noted with FTD/TPI. CONCLUSION: As in patients with GC, FTD/TPI showed an efficacy benefit in patients with GEJC in the TAGS trial, along with demonstrating a manageable safety profile. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10120-021-01156-x.