Comparative cost-effectiveness of tislelizumab plus chemotherapy versus standard chemotherapy in first-line treatment for extensive-stage small cell lung cancer: perspectives from the U.S. and Chinese healthcare systems

Abstract Background Tislelizumab combined with chemotherapy has shown significant clinical benefits in improving overall survival compared to chemotherapy alone for patients with extensive-stage small-cell lung cancer (ES-SCLC). Aim This study aimed to evaluate its cost-effectiveness for both US and Chinese ES-SCLC patient populations. Method We conducted an economic evaluation using a Markov state-transition model, reflecting the perspectives of US and Chinese healthcare payers. Baseline patient characteristics and essential clinical data were obtained from the RATIONALE-312 trial. The costs and utilities were derived from open-access databases and published literature. The primary outcomes measured included quality-adjusted life years (QALYs), incremental cost-effectiveness ratio (ICER), incremental net health benefit (INHB), and incremental net monetary benefit (INMB). Uncertainties in the model were addressed by probabilistic sensitivity analysis (PSA) and one-way sensitivity analysis (OWSA). Results In the base-case analysis, the addition of tislelizumab to chemotherapy provided an incremental gain of 0.27 QALYs at an additional cost of $8,352.18, resulting in an ICER of $31,136.52 per QALY. Although below the willingness-to-pay (WTP) threshold of China of $38,042.49 per QALY, the cost-effectiveness was marginal, with an INHB of 0.05 QALYs and an INMB of $1,852.49. In the US, despite a slightly higher effectiveness gain of 0.29 QALYs, the increased cost of $45,157.35 resulted in an unfavorable ICER of $157,117.67 per QALY, exceeding the US WTP threshold of $150,000.00. PSA showed probabilities of cost-effectiveness of tislelizumab plus chemotherapy at 92.52% in China and 44.07% in the US. Conclusions Tislelizumab with chemotherapy may be a cost-effective first-line treatment option for ES-SCLC in China but not the US, highlighting significant geographical disparities in healthcare economics.