Tislelizumab plus chemotherapy as first-line treatment for recurrent or metastatic nasopharyngeal cancer: A multicenter phase 3 trial (RATIONALE-309)

Checkpoint inhibitors are effective in recurrent/metastatic nasopharyngeal cancer (R/M NPC). RATIONALE-309 (NCT03924986) randomized 263 treatment-naive R/M NPC patients to tislelizumab or placebo every 3 weeks (Q3W), plus chemotherapy (Q3W for 4-6 cycles). At interim analysis, progression-free survival (PFS) was significantly longer with tislelizumab-chemotherapy versus placebo-chemotherapy (hazard ratio: 0.52; 95% confidence interval: 0.38, 0.73; p < 0.0001). PFS benefit for tislelizumab-chemotherapy versus placebo-chemotherapy was observed regardless of programmed death-ligand 1 expression. PFS after next line of treatment and overall survival showed favorable trends for tislelizumab-chemotherapy versus placebo-chemotherapy. The safety profile was similar between arms. Gene expression profiling (GEP) identified immunologically "hot" tumors, and showed an activated dendritic cell (DC) signature was associated with tislelizumab-chemotherapy PFS benefit. Our results support that tislelizumab-chemotherapy should be considered as first-line treatment for R/M NPC, and GEP and activated DC signature results may help identify patients who might benefit most from immunochemotherapy treatment. VIDEO ABSTRACT.