RISEDRONATE SODIUM IS A PYRIDINYL BISPHOSPHONATE THAT BINDS TO BONE HYDROXYAPATITE AND INHIBITS OSTEOCLAST-MEDIATED BONE RESORPTION. THE BONE TURNOVER IS REDUCED WHILE THE OSTEOBLAST ACTIVITY AND BONE MINERALISATION ARE PRESERVED. IN PRECLINICAL STUDIES RISEDRONATE SODIUM DEMONSTRATED POTENT ANTI-OSTEOCLAST AND ANTIRESORPTIVE ACTIVITY, AND DOSE DEPENDENTLY INCREASED BONE MASS AND BIOMECHANICAL SKELETAL STRENGTH.