Daily subcutaneous injection of teriparatide : the progress and current issues

Daily subcutaneous injection of teriparatide, which consists of 34 amino acids of N-terminal of parathyroid hormone, has been investigated as a therapy for osteoporosis. It has been used since 2010 in Japan. Since teriparatide markedly stimulates bone formation, its daily injection increases bone volume mainly at the cancellous bone and significantly reduces vertebral and non-vertebral fracture risk. Because of the limitation (2 years) of the use in the life span, sequential treatment following teriparatide is needed. When combined with an antiresorptive agent, teriparatide showed additive increase in bone mineral density. However, it remains uncertain which agent is the best for the combination and what schedule is the most effective. Since teriparatide reduces back pain and stimulates bone repair, it is suitable for patients with back pain or with severe osteoporosis.