Odanacatib is a potent, selective, and neutral cathepsin K inhibitor, an enzyme involved in bone resorption. Merck & Co was developing odanacatib, a once-weekly, oral Odanacatib, for the treatment of postmenopausal osteoporosis and osteoporosis in men. Merck & Co. has discontinued development of its cathepsin K inhibitor odanacatib, citing an increased risk of cardiovascular events for the osteoporosis drug.