Bone-targeted therapy in metastatic prostate cancer: osteoclast inhibitors and bone-seeking radiopharmaceuticals

Metastatic prostate cancer has a tropism for bone and often spares soft tissues. Drugs that target the bone have a unique niche in metastatic prostate cancer. A variety of pharmaceutical agents have been investigated in this disease with endpoints including pain, skeletal related events, and overall survival. Herein we focus on two broad classes: osteoclast inhibitors, such as bisphosphonates and antibodies to receptor activator of nuclear factor-κβ ligand; and bone-seeking radiopharmaceuticals, such as strontium-89 chloride, samarium-153 lexidronam, and radium-223 chloride. Pertinent clinical trials as well as currently ongoing trials will be reviewed.