Fortnightly Review: The therapeutic use of bisphosphonates

Abstract

Bisphosphonates are characterised by two carbon-phosphorus bonds, the carbon atom replacing the oxygen in the P-O-P (phosphorus-oxygen- phosphorus) bond of pyrophosphate (fig 1) and the P-C-P (phosphorus carbon-phosphorus) bond conferring resistance to chemical and enzymatic hydrolysis. Different substitutions on the carbon atom have created several different bisphosphonates, each with its own individual pharmacological properties. The first bisphosphonate to be used therapeutically was etidronate, and subsequently many others have been developed. In order of increasing potency of antiresorptive activity the main bisphosphonates are etidronate, tiludronate, clodronate, pamidronate, alendronate, and risendronate.