Cost-savings from fracture prevention with zoledronate in randomised controlled trials

Zoledronate prevented fractures in four large trials in cohorts that varied from low to high risk of fracture. Cost-effectiveness analyses are important tools used in funding and regulatory decisions about pharmaceutical agents, and zoledronate generally has appeared to be cost-effective. We used a simple approach to compare zoledronate costs with the savings from fractures prevented to complement previous cost-effectiveness analyses. 18-month costs of major osteoporotic fractures were obtained from published data from 7 US sites in the ICUROS study, costs of zoledronate medication from Medicare, and infusion costs estimated empirically. We applied these costs to data on major osteoporotic fracture from the four trials. We repeated these analyses using 12-month costs from 11 international ICUROS sites. In the trials with high-risk and intermediate-high risk cohorts, the cost-savings from major osteoporotic fractures prevented were approximately US $500,000/1000 patients/3y. In the low-intermediate-risk trial, they were $660,000/1000/6y, and in the low-risk trial, $240,000/1000/10y. When the international fracture cost data were used, these savings approximately doubled. In all four trials, the total costs of zoledronate were substantially less than the savings from fractures prevented, with annual savings ranging from $11-$88/patient/year in low-risk to high-risk patients. The cost-neutral zoledronate cost (maximum infusion cost plus medication cost) ranged from $160-$175 using the US fracture cost data, and was about $350 using international cost data. In summary, in four trials with cohorts at various risk of fracture ranging from low to high risk, zoledronate produced substantial nett savings because the costs of fractures prevented out-weighed total zoledronate costs.