IBIS II bone sub-study

31 January 2011



To evaluate the impact of anastrozole on bone health and whether the bone treatment drug risedronate can prevent loss of bone density women participating in the IBIS II.

Scientific Title

IBIS II Bone Sub-Protocol. A randomised, double-blind trial to assess the effects on bone mineral density and bone biomarkers of anastrozole when used to prevent breast cancer in postmenopausal women.


Aromatase inhibitors prevent breast cancer in postmenopausal women at high risk of the disease but are associated with accelerated bone loss. The IBIS II bone sub-study assesses the effectiveness of oral drug risedronate for prevention of reduction in bone mineral density after three years of follow-up in a subset of patients in the IBIS-II trial.