In the AZURE trial , an open-label , international , multicentre , randomised , controlled , parallel-group phase 3 trial , women ( age 18 years ) with stage II or III breast cancer were randomly assigned ( 1:1 ) by a central automated 24-h computer-generated telephone minimisation system ( balanced for number of involved axillary lymph nodes , tumour stage , oestrogen receptor status , type and timing of systemic therapy , menopausal status , statin use , and treatment centre ) to receive standard adjuvant systemic treatment alone ( control group ) or with 4 mg intravenous zoledronic acid every 3-4 weeks for six doses , then every 3 months for eight doses , followed by every 6 months for five doses , for a total of 5 years of treatment .