Cost-effectiveness of abiraterone versus docetaxel in the treatment of metastatic hormone naïve prostate cancer

Purpose: Prostate cancer is the second leading cause of cancer death in men in the US. Since 2015, landmark studies have demonstrated improved survival outcomes with the use of docetaxel (DCT) or abiraterone (AA) in addition to androgen deprivation therapy (ADT) in the metastatic hormone-naïve setting. These treatment strategies have not been prospectively compared but have similar overall survival benefits despite differing mechanisms of action, toxicity, and cost. We performed a cost-effectiveness analysis to provide insight into the value of AA vs. DCT in the first-line treatment of metastatic prostate cancer. Materials and Methods: We developed Markov models by using a US-payer perspective and a 3-year time horizon to estimate costs (2018 US$) and progression-free quality-adjusted life years (PF-QALYs) for ADT alone, DCT, and AA. Health states were defined as initial state, treatment states according to experience of an adverse event, and progressed disease/death. State transition probabilities were derived from rates for drug discontinuation, frequency of adverse events, disease progression, and death from the randomized phase III trials ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) and LATITUDE. Univariate and probabilistic sensitivity analyses were conducted to evaluate model uncertainty. Results: DCT resulted in an increase of 0.32 PF-QALYs and $16,100 in cost and AA resulted in an increase of 0.52 PF-QALYs and $215,800 in cost compared to ADT alone. The incremental cost-effectiveness ratio for DCT vs. ADT was $50,500/PF-QALY and for AA vs. DCT was $1,010,000/PF-QALY. Probabilistic sensitivity analysis demonstrated that at a willingness-to-pay threshold of $150,000/PF-QALY AA was highly unlikely to be cost-effective. Conclusion: DCT is substantially more cost-effective than AA in the treatment of metastatic hormone naïve prostate cancer.