Aims: Pembrolizumab has demonstrated significantly prolonged disease-free survival and overall survival (OS) among adult patients post-nephrectomy who have an intermediate-high risk, high-risk, or M1 stage with no evidence of disease (M1 NED) renal cell carcinoma (RCC) with clear cell component. The aim of this study was to evaluate the cost-effectiveness of pembrolizumab for patients with RCC post-nephrectomy versus observation in Switzerland.
Materials and methods: A previously published Markov model was adapted for the Swiss setting to estimate the cost-effectiveness of adjuvant pembrolizumab versus observation from the Swiss statutory health insurance perspective. Transition probabilities between model states were estimated using survival curves from KEYNOTE-564 (data cut-off: 14 June 2021). Outcomes included costs (2022 Swiss francs [CHF]), quality-adjusted life-years (QALYs), and life-years (LYs), measured over a lifetime horizon. Costs included drug acquisition and administration for adjuvant and subsequent therapy. Both costs and effectiveness were discounted at 3.0% annually. Cost-effectiveness was evaluated at a hypothetical willingness-to-pay (WTP) threshold of CHF 100,000. Sensitivity was assessed through scenario analyses as well as deterministic and probabilistic sensitivity analyses.
Results: Over a lifetime horizon, the total incremental cost for pembrolizumab versus observation was CHF 59,089, providing incremental gains of 0.90 QALYs (1.07 LYs); the incremental cost-effectiveness ratio was CHF 65,299/QALY. Pembrolizumab was deemed cost-effective versus observation, with a 69.9% probability of cost-effectiveness.
Limitations: A more recent interim analysis data cut from KEYNOTE-564 with median follow up of 57.2 months has since been published; however, these were not available at the time of analysis. It would likely have minimal impact on transition probabilities from disease-free, and the current approach remains conservative for predicting OS for pembrolizumab.
Conclusions: As an adjuvant treatment of RCC post-nephrectomy, pembrolizumab was found to be cost-effective versus observation in Switzerland at a WTP threshold of CHF 100,000/QALY. Policy makers should consider pembrolizumab as an adjuvant treatment for patients with RCC post-nephrectomy when making decisions regarding resource allocation.
Keywords: H; H5; H51; I; I1; I10; Pembrolizumab; adjuvant therapy; economic evaluation; immunotherapy; kidney cancer.