Zoledronic acid : a review of its use in the management of bone metastases of malignancy.

Zoledronic acid (Zometa), a third-generation amino-bisphosphonate, has been approved in the US, the EU and many other countries worldwide for the prevention of skeletal-related events in patients with bone metastases of malignancy. In several well designed trials, zoledronic acid 4 mg administered as a 15-minute infusion every 3-4 weeks was effective in reducing the occurrence of skeletal complications in patients with bone metastases secondary to multiple myeloma, breast cancer or prostate cancer. Zoledronic acid was as effective as pamidronic acid in reducing the occurrence of skeletal complications in patients with multiple myeloma or breast cancer. In patients with solid tumours other than breast or prostate cancer, zoledronic acid did not show significant clinical benefit over placebo in terms of the primary endpoint; however, some benefit of therapy in terms of secondary endpoints was observed with zoledronic acid relative to placebo. Its efficacy in a broad range of tumours and short infusion time (15 minutes) are an advantage over other available bisphosphonates. Modelled pharmacoeconomic analyses in patients with breast cancer suggested that zoledronic acid therapy is cost effective relative to no therapy with regard to the cost per quality-adjusted life-year (QALY) gained; however, results were mixed when zoledronic acid was compared with other commonly used bisphosphonates. Zoledronic acid is generally well tolerated; the risk of osteonecrosis of the jaw may be minimized by adhering to recommendations regarding dental therapy. Additional efficacy and economic data are required to definitively position zoledronic acid with respect to other bisphosphonates. Nevertheless, available clinical data indicate that zoledronic acid is an effective treatment option for the management of bone metastases of malignancy.