Cisplatin-sparing toripalimab plus chemoradiotherapy feasible in advanced NPC

Incorporating toripalimab into induction chemotherapy and radiotherapy without concurrent cisplatin appears to be efficacious and associated with low toxicity in patients with locoregionally advanced nasopharyngeal cancer (NPC), according to a phase III trial.

Conducted at 13 hospitals in China, the trial included 532 patients (median age 47 years, 25.2 percent female) with T4N1M0 or T1-4N2-3M0 NPC. These patients were randomly assigned to receive toripalimab with gemcitabine-cisplatin induction chemotherapy and concurrent cisplatin-radiotherapy (100 mg/m² triweekly for 2 cycles) (standard therapy group, n=266) or the same regimen without concurrent cisplatin (cisplatin–sparing group, n=266). The 17 cycles of toripalimab (240 mg triweekly) were spread out across the induction, radiotherapy, and adjuvant phases as 3, 3, and 11 cycles, respectively.

A total of 400 patients (75.2 percent) completed the trial per protocol.

Coprimary endpoints were failure-free survival (noninferiority margin 8 percent) and incidence of all-grade vomiting (superiority design). Secondary endpoints included overall survival, locoregional recurrence-free survival, distant metastasis–free survival, safety, tumour response, quality of life, and tolerability.

Over a median follow-up of 37 months, the 3-year failure-free survival rate was 88.3 percent in the cisplatin–sparing group vs 87.6 percent in the standard therapy group, with the difference establishing the noninferiority of the concurrent cisplatin–sparing regimen (p=0.002 for noninferiority; stratified hazard ratio, 0.92, 95 percent confidence interval [CI], 0.66–1.79).

Moreover, the incidence of all-grade vomiting was significantly lower in the cisplatin-sparing group than in the standard therapy group (26.2 percent vs 59.8 percent; p<0.001).

Patients in the cisplatin–sparing group reported better quality of life (participation rate, 87.5 percent) and tolerability (participation rate, 94.7 percent) in terms of gastrointestinal, functional, and global health status as compared with those in the standard therapy group.