Initial Insights From JUPITER-02 - Toripalimab Efficacy in R/M NPC

The JUPITER-02 trial was a randomized phase 3 study designed to evaluate the addition of PD-1 blockade to standard chemotherapy in patients with recurrent or metastatic nasopharyngeal carcinoma R/M NPC, primarily those with EBV-driven disease. The trial enrolled 289 patients and randomized randomly assigned them 1:1 to receive either a combination of gemcitabine (1 g/m²) and cisplatin (80 mg/m²) with a PD-1 inhibitor, or chemotherapy alone. Patients in the experimental arm received up to six 6cycles of chemotherapy along with and the immunotherapy agent, followed by maintenance immunotherapy. The control arm received chemotherapy plus placebo followed by placebo maintenance.

The primary endpointend point was progression-free survival (PFS), and the results were striking. The median PFS was 21.4 months in the immunotherapy group compared to with 8.2 months in the control arm, corresponding to a hazard ratio an HR of 0.52. This represents a substantial improvement in disease control. Although cross-trial comparisons should be made cautiously, these results stood out relative to prior studies of other PD-1 agents, which had reported shorter PFS durations when combined with chemotherapy.

Biomarker analyses provided further insight. Patients with lower circulating EBV DNA levels at baseline had better outcomes overall, regardless of treatment arm. However, those with higher EBV levels seemed to benefit more significantly from the addition of immunotherapy, suggesting a possible link between viral burden and response. Additionally, PD-L1 positivity—defined as expression on tumor or immune cells—was common among enrolled patients (~approximately 83%). Patients with PD-L1–positive disease had improved outcomes, but the benefit of adding immunotherapy was observed across PD-L1 subgroups. In those with higher PD-L1 expression, the hazard ratio HR for survival improved further, suggesting enhanced responsiveness in this subset.