A new class of drugs appears to be on the way to biting the dust. Bisphosphonates are prescribed to strengthen bone tissue. Chemically, they are made up of two groups of phosphates (phosphorus combined with oxygen) linked to carbon with two side chains. Fosamax and Actonel, perhaps the best known ones, are taken orally to prevent or treat osteoporosis. Other bisphosphonates, like Areida and Zometa, are given intravenously, usually for cancer patients and those suffering from a chronic bone disorder called Paget’s disease, to aggressively treat bone deterioration.

While we might imagine bone as a very solid, enduring structure, it is actually constantly in a state of flux: it is regenerated with new cells while old one are removed. Osteoclasts are a type of bone cell that perform this latter task and bisphosphonates work by blocking their function.