27P Concurrent chemoradiotherapy and immunotherapy for locally advanced cervical cancer: A cost-effectiveness analysis based on the KEYNOTE-A18 trial

Immunotherapy administration can improve chemoradiotherapy (CCRT) efficacy in newly diagnosed, high-risk, locally advanced cervical cancer (LACC). Given the importance of balancing the costs of innovative therapeutics against their efficacy, this study was developed to assess the cost-effectiveness from the perspective of payers in America, Europe, and Asia. The main survival and other relevant parameters of 1,060 LACC patients from the KEYNOTE-A18 trial were collected to establish a lifetime three-state Markov model to evaluate the cost and effectiveness of pembrolizumab-CCRT and CCRT. Primary outcome measures included total cost, life-years (LYs), quality-adjusted LYs (QALYs), incremental cost-effectiveness ratio (ICER), incremental net monetary benefit (INMB), and incremental net health benefits (INHB) at countries' traditional willingness-to-pay (WTP) thresholds. Model stability was also examined through sensitivity analyses. The USA, Italy, and China are selected as representative countries for each of the three continents, assuming that their WTP thresholds were $150,000, $43,749, and $37,766 per QALY. The increased efficacy and costs of pembrolizumab-CCRT versus CCRT were 2.52 QALYs (3.11 LYs) and $346,479, 2.30 QALYs (2.81 LYs) and $236,776, 1.79 QALYs (2.12 LYs) and $29,027, calculating the ICER for the three countries as $137,500/QALY ($111,499/LY), $102,758/QALY ($84,192/LY), and $16,217/QALY ($13,726/LY), respectively. The respective INHBs were 0.21 QALY, -3.11 QALY, and 1.02 QALY, and pembrolizumab-CCRT was exhibited cost-effectiveness opportunities of 62.68%, 12.53%, and 75.23% at the selected WTP threshold, respectively. At current prices, pembrolizumab-CCRT represents a cost-effective alternative for patients with LACC in the USA and China, but not in Italy.