Five-Year Outcome of Camrelizumab Plus Chemotherapy in Recurrent or Metastatic Nasopharyngeal Carcinoma: A Secondary Analysis of the CAPTAIN-1st Randomized Clinical Trial.

[IMPORTANCE] Programmed cell death 1 protein (PD-1) or programmed cell death 1 ligand 1 inhibitors plus chemotherapy is the current standard first-line treatment of recurrent or metastatic nasopharyngeal carcinoma (RM-NPC). However, the long-term survival benefits at the 5-year benchmark remain uncertain.

[OBJECTIVE] To determine whether adding camrelizumab to chemotherapy significantly improved 5-year overall survival (OS) as first-line treatment for RM-NPC, compared with chemotherapy alone.

[DESIGN, SETTING, AND PARTICIPANTS] The CAPTAIN-1st trial was a randomized, double-blind, phase 3 trial conducted at 28 hospitals in China. Between November 13, 2018, and November 29, 2019, patients with treatment-naive RM-NPC were enrolled. This secondary analysis of the CAPTAIN-1st trial was prespecified. Data analysis was conducted on June 1, 2025.

[INTERVENTIONS] Patients were randomized (1:1) to receive camrelizumab or placebo in combination with gemcitabine and cisplatin for 4 to 6 cycles, followed by maintenance therapy with camrelizumab or placebo until disease progression, unacceptable toxic effects, or completion of 2 years of treatment.

[MAIN OUTCOME] The primary end point, progression-free survival per independent review committee, has been reported previously. Herein, the secondary end point of OS is reported as prespecified in the protocol.

[RESULTS] Among 263 randomized patients (134 in randomized to camrelizumab, 129 to placebo), baseline characteristics were generally balanced between groups, except for age. The mean (SD) age was 49 (11.25) years, and 218 patients (82.9%) were male individuals, 45 (17.1%) were female individuals. With a median survival follow-up of 63.5 (95% CI, 61.2-64.6) months for the camrelizumab group and 63.0 (95% CI, 60.8-64.6) months for the placebo group, 85 (63.4%) and 95 (73.6%) deaths occurred, respectively. Median OS was 34.5 months (95% CI, 29.4-45.7) with camrelizumab vs 26.6 months (95% CI, 19.8-33.5) with placebo (hazard ratio [HR], 0.74; 95% CI, 0.55-0.99; 2-sided P = .047). After adjusting for age imbalance, the HR was 0.65 (95% CI, 0.48-0.89; P = .01). The 5-year OS rates were 37.8% vs 24.2%, reflecting an absolute difference of 13.6% (95% CI, 2.4%-24.8%; P = .02) in favor of camrelizumab. The OS benefits were generally consistent across subgroups. In the camrelizumab group, patients who achieved rapid clearance of Epstein-Barr virus (EBV) DNA had significantly longer OS compared with those without EBV DNA clearance (HR, 0.32; 95% CI, 0.18-0.58; P < .001).

[CONCLUSIONS AND RELEVANCE] In this secondary analysis of a randomized clinical trial, the addition of camrelizumab to chemotherapy produced statistically significant and clinically meaningful 5-year OS benefits compared with chemotherapy alone in the first-line treatment of RM-NPC. These findings provided the first 5-year evidence supporting the benefit of PD-1-based chemoimmunotherapy in this setting.

[TRIAL REGISTRATION] ClinicalTrials.gov Identifier: NCT03707509.