Anabolic therapy for osteoporosis

Until recently, calcium supplementation with vitamin D and hormone replacement therapy were the mainstays of treating osteoporosis associated with the menopause. Hormone replacement therapy, indeed, was (and is) effective in preventing fracture, but is no longer to be considered to be a primary indication for this purpose. Thus, while continuing with calcium and vitamin D, drug therapy now consists of the antiresorptive agents: raloxifene, calcitonin, and the bisphosphonates. These drugs reduce bone turnover, and do prevent fractures, but are limited to halting further deterioration of skeletal microarchitecture. The newest agent against osteoporosis is teriparatide, an amino terminal fragment parathyroid hormone containing 34 amino acids. PTH(1-34), or teriparatide, exhibits many of the classical actions of the whole molecule. It is anabolic with respect to bone when used according to well-defined protocols. Bone microarchitecture is restored with increases in cortical thickness and in connectivity. This paper describes the activities as known at present of the bisphosphonates and of teriparatide and reviews studies of their use alone and in combination with each other.