A third-generation heterocyclic nitrogen-containing bisphosphonate that inhibits the prenylation of GTPases critical to the signaling events related to osteoclast-mediated bone resorption; has a high affinity for hydroxyapatite (Ki = 3.47 μM) and binds directly to mineralized bone where it decreases bone resorption by inhibiting osteoclast proliferation and inducing osteoclast apoptosis.