Zoledronic acid versus pamidronate: Cost minimisation in bone metastasis

The objective of this study was to evaluate the economic and organisational consequences of the substitution of pamidronate with zoledronic acid in the adjunct treatment of bone metastasis in patients with breast cancer and multiple myeloma in a European context. A cost minimisation analysis was carried out. Clinical data were extracted from clinical trials of pamidronate versus zoledronic acid. Resource consumption and cost data were collected at different Spanish oncology infusion sites. While the acquisition cost of zoledronic acid is higher compared with pamidronate, zoledronic acid is superior to pamidronate for the treatment of hypercalcaemia of malignancy and in avoiding palliative radiotherapy. Moreover, it is at least as effective as 90 mg pamidronate in reducing skeletal complications in patients with bone lesions from myeloma or breast cancer. It therefore reduced nurse monitoring, occupation of infusion chairs and radiotherapy sessions, implying savings in health care resources. The net of these expenses in switching from pamidronate to zoledronic acid would produce an additional cost of €134.92 per patient per year, which is equivalent to 5.1% of the current drug cost of a treatment with pamidronate. Savings due to the shorter infusion time and the better outcomes of zoledronic acid in avoiding palliative radiotherapy can almost completely compensate its higher acquisition cost compared with pamidronate.