Cost-effectiveness of Pembrolizumab in Second-line Advanced Bladder Cancer

Background: Immune-modulating drugs have recently been introduced to the second-line setting of advanced bladder cancer. Pembrolizumab increases overall survival and is associated with less toxicity compared with chemotherapy in this setting based on the Keynote 045 study. The high cost of immunotherapy necessitates an assessment of its value by considering both efficacy and cost. Objective: To estimate the cost-effectiveness of pembrolizumab for the second-line treatment of advanced bladder cancer from the perspective of payers in multiple countries. Design, setting, and participants: We developed a Markov model to compare the cost and effectiveness of pembrolizumab with those of chemotherapy in the second-line treatment of advanced bladder cancer based on the Keynote 045 study. Drug costs were acquired for the United States (US), United Kingdom (UK), Canada, and Australia. All costs were converted from local currency to US dollars at the exchange rates in September 2017. Outcome measurements and statistical analysis: Health outcomes were measured in quality-adjusted life-years (QALYs). Results and limitations: Pembrolizumab generated a gain of 0.36–0.37 QALYs compared with chemotherapy. Our analysis established the following incremental cost-effectiveness ratios (ICERs) for pembrolizumab versus chemotherapy in second-line advanced bladder cancer treatment: US $122 557/QALY; UK $91 995/QALY; Canada $90 099/QALY; and Australia $99 966/QALY. The willingness-to-pay (WTP) thresholds per QALY are considered to be around 100 000–150 000 US dollars for the US, 20 000–50 000 pounds for the UK (US$25 000–65 000), 20 000–100 000 CAD for Canada (US$16 000–80 000), and 40 000–75 000 AUD for Australia (US$32 000–60 000). Conclusions: Cost-effectiveness and WTP thresholds vary between countries. Compared with the other countries examined, US drug prices were found to be the highest, leading to the highest ICER. With standard WTP thresholds, pembrolizumab may be considered cost-effective in the US but not in the other countries examined. Patient summary: This article assessed the cost-effectiveness of pembrolizumab for the treatment of patients with metastatic bladder cancer who had previously failed one treatment regimen. It would cost $122 557 in the United States, $91 995 in the United Kingdom, $90 099 in Canada, and $99 966 in Australia to gain one quality-adjusted life-year with pembrolizumab versus chemotherapy in these patients, which may be considered cost-effective only in the United States because of the differences in willingness-to-pay thresholds. Incremental cost-effectiveness ratios established for pembrolizumab versus chemotherapy in second-line advanced bladder cancer were: United States, $122 557/ quality-adjusted life-year (QALY); United Kingdom, $91 995/QALY; Canada, $90 099/QALY; and Australia $99 966/QALY. Variation in willingness-to-pay thresholds between these countries allows pembrolizumab to be considered cost-effective only in the United States.