ONO 5334 is a novel cathepsin K inhibitor. Inhibited bone resorption in human osteoclast and reduced calcium level increased by PTHrP in thyroparathyroidectomized rat and decreased serum and urine C-telopeptide of type I collagen level in monkey. Values in postmenopausal patient with osteoporosis, increases lumbar spine, total hip and femoral neck bone minerals. Molecular Formula: C21H34N4O4S Molecular Weight: 438.58