Cathepsin K (CTSK) and Bone Resorption

Abstract An imbalance in bone formation and bone resorption results in the bone loss that characterizes osteoporosis. An absolute or relative increase in bone resorption by osteoclasts can significantly contribute to this bone loss. Cathepsin K is a lysosomal protease responsible for bone degradation by osteoclasts. Pharmacological use of cathepsin K inhibitors such as odanacatib for osteoporosis has shown benefit, though the clinical development of these agents had to be discontinued due to potential adverse events. Preclinical and clinical studies on cathepsin K and its inhibitors have shown the potential for an adjuvant antiresorptive agent, and continue to guide future research.