Abstract
BACKGROUND: Toripalimab, combined with gemcitabine and cisplatin, has been approved as the first-line treatment for recurrent or metastatic nasopharyngeal carcinoma (RM-NPC), representing a significant milestone as the first FDA-approved innovative therapy for this condition. Despite this achievement, there's a lack of data on the cost-effectiveness of toripalimab for RM-NPC patients in the American context. METHODS: To assess the cost-effectiveness of toripalimab plus chemotherapy versus chemotherapy alone, a 3-state partitioned survival model was constructed. The study involved participants with characteristics matching those in the JUPITER-02 trial. Cost and utility inputs were collected from literature. Main outcomes measured were quality-adjusted life year (QALY), and incremental cost-effectiveness ratio (ICER). Univariate and probabilistic sensitivity analyses, subgroup analyses, and scenario analyses were conducted to verify the robustness of results. RESULTS: The study found that the toripalimab regimen resulted in 4.390 QALYs at a cost of $361,813, while the chemotherapy-only regimen yielded 1.685 QALYs at a cost of $161,632. This translates to an ICER of $74,004/QALY, below the willingness-to-pay threshold of $150,000/QALY. Sensitivity analyses indicated that utility values, discount rate, and the price of toripalimab significantly impact INMB. With an 87.10% probability of being cost-effective at a $150,000/QALY threshold, the probabilistic sensitivity analysis supports toripalimab plus chemotherapy as a viable option. Scenario analysis showed that toripalimab remains cost-effective unless its price increases by 125%. Additionally, a simulated 15-year study period increases the ICER to $88,026/QALY. Subgroup analysis revealed ICERs of $76,538/QALY for PD-L1 positive and $70,158/QALY for PD-L1 negative groups. CONCLUSIONS: Toripalimab in combination with chemotherapy is likely to be a cost-effective alternative to standard chemotherapy for American patients with RM-NPC. This evidence can guide clinical and reimbursement decision-making in treating RM-NPC patients.