Cost-efficiency and budget-neutral expanded access modeling of the novel PD-1 inhibitor toripalimab versus pembrolizumab in recurrent or metastatic nasopharyngeal carcinoma.

Aims: To estimate, in the setting of recurrent or metastatic nasopharyngeal carcinoma (R/M NPC) for an assumed 1,207 incident US cases in 2024, (1) the cost-efficiency of a toripalimab-gemcitabine-cisplatin regimen compared to a similar pembrolizumab regimen; and (2) the budget-neutral expanded access to additional toripalimab cycles and regimens afforded by the accrued savings. Methods: Simulation modeling utilizing two cost inputs (wholesale acquisition cost (WAC) at market entry and an ex ante toripalimab price point of 80% of pembrolizumab average sales price (ASP)) and drug administration costs over one and two years of treatment with treatment rates ranging from 45% to 90%. In the absence of trial data for pembrolizumab-gemcitabine-cisplatin in R/M NPC, it is assumed that such regimen would be comparable to toripalimab-gemcitabine-cisplatin in efficacy and safety. Results: In the models utilizing the WAC, toripalimab saves $2,223 per patient per cycle and $40,014 over 1 year of treatment ($77,805 over 2 years). Extrapolated to the 1,207-patient panel, estimated 1-year savings range from $21,733,702 (45% treatment rate) to $43,467,404 (90% rate). Reallocating these savings permits budget-neutral expanded access to an additional 2,359 (45% rate) to 4,717 (90% rate) toripalimab maintenance cycles or to an additional 126 (45% rate) to 252 (90%) full 1-year toripalimab regimens with all agents. Two-year savings range from $42,259,976 (45% rate) to $84,519,952 (90% rate). Reallocating these efficiencies provides expanded access ranging from an additional 4,586 (45% rate) to 9,172 (90% rate) toripalimab cycles or to an additional 128 to 257 full 2-year toripalimab regimens. The ex ante ASP model showed similar results. Conclusion: This simulation demonstrates that treatment with toripalimab generates savings that enable budget-neutral funding for up to an additional 252 regimens with toripalimab-gemcitabine-cisplatin for one full year, the equivalent of approximately 21% of the 2024 incident cases of R/M NPC in the US.