Cost-Effectiveness Analysis of Contemporary Advanced Prostate Cancer Management: A Markov Model for the Canadian Context

OBJECTIVES: Recently, there has been a proliferation of treatments for the management of prostate cancer (PCa), including numerous second-generation anti-androgens (SGAAs). Despite improving patient outcomes, SGAA use typically leads to resistance and prevents effective rechallenges. Consequently, the optimal timing of SGAA use is an open question. Although there are health economic analyses of novel PCa treatments for specific patient states, there is a lack of analogous dynamic analyses. Our paper aims to fill this gap.

METHODS: We developed a Monte Carlo Markov model to simulate the management of advanced PCa to end-of-life. We modeled patients who begin in metastatic and non-metastatic hormone-sensitive PCa (mHSPC and nmHSPC), with risk stratification for mHSPC, progressing to metastatic and non-metastatic castration-resistant PCa (mCRPC and nmCRPC). Using current Canadian guidelines, we simulated all admissible treatment sequences over these states over a 15-year horizon and compared outcomes for each sequence.

RESULTS: We find and report the best treatment sequences over a 15-year horizon for a variety of health outcomes as well as net health benefits (NHB), expressed as quality-adjusted life years (QALYs) minus costs for a range of willingness to pay (WTP) values. Early SGAA use delivers the best health outcomes for all patients and the best NHB for mHSPC-starting patients at moderate to high WTP (NHB gain: 0.93–1.5 QALYs at C$100k–150k WTP). However, early SGAA use is comparable to late SGAA use and no SGAA use for nmHSPC-starting patients at all WTP (NHB gain: -0.27–0.18 QALYs at C$50–150k WTP) and mHSPC-starting patients at low WTP (NHB gain: 0.09–0.32 QALYs at C$50k).

CONCLUSIONS: We conclude that from health and health-economic perspectives, there is a wide range of treatment strategies which deliver near-best average patient outcomes. Broadly, SGAAs are more effective during early stages of PCa, but not using SGAAs is near-optimal for nmHSPC patients and/or cost-constrained payers.