Analysis of the cost-effectiveness of zoledronic acid for the prevention of skeletal-related events in patients with prostate cancer and bone metastases: A comparison across four European countries.

Abstract

4679 Background: Zoledronic acid (ZOL) is the only bisphosphonate indicated for the prevention of skeletal related events (SREs) in patients with bone metastases secondary to prostate cancer. This analysis estimates and compares the cost-effectiveness of ZOL versus placebo (PBO) for this indication across 4 countries: France (FR), Germany (DE), Portugal (PT), and the Netherlands (NL). Methods: The incremental costs and quality-adjusted life years (QALY) associated with ZOL therapy versus PBO were estimated using a literature-based decision analytic model based on data from a randomized trial (4 mg ZOL [n = 214] versus PBO [n = 208] for 15 months). The model included assumptions about SREs, mortality, drug and administration costs, SRE costs, reduced quality of life because of SREs and bone pain, and therapy duration. The costs of SREs were estimated using primarily Diagnosis Related Group (DRG) tariff information (supplemented with published literature) in FR and DE, and using published data reporting retrospective medical record review cost analysis in NL and PT. Results: Over 15 months, the cumulative number of SREs projected was 0.83 for ZOL patients versus 1.66 for PBO patients. ZOL reduced SRE costs by €2,659 to €4,005, depending on the country. The greatest SRE costs savings were estimated to occur in NL, followed by PT, DE, and FR. Including drug costs, ZOL reduced total costs by €62 in PT and €301 in NL, but increased costs by €562 in DE and €1,022 in FR vs. PBO. However, ZOL also increased quality-adjusted survival by 0.03566 QALY per patient, resulting in an incremental cost per QALY gained versus PBO of €15,770 in DE and €28,648 in FR. In all countries the cost-effectiveness ratio with ZOL treatment was favorable and substantially below the internationally accepted €50,000/QALY threshold value. Costs and QALYs were saved with ZOL in PT and NL. Conclusions: In patients with bone metastasis secondary to prostate cancer, ZOL is shown to be economically attractive. The cost-effectiveness ratio for ZOL is below standard cost-effectiveness thresholds observed by most healthcare systems. In PT and NL, ZOL is also cost saving versus PBO. Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Novartis Novartis Novartis Novartis