[Large clinical trials for osteoporosis]

The prevention and treatment of osteoporosis are now a necessary goal because of the aging of the population and the social and economic costs of fracture complications. The publication of guidelines by registration agencies during the last 10 years has provided precise rules for evaluating new drugs designed for the prevention and treatment of postmenopausal osteoporosis. The benefit of combination treatment with calcium and vitamin D in osteoporotic patients has clearly been proven, especially among the oldest patients, but results of prospective studies designed for the prevention of fracture risk are conflicting. In the Fracture Intervention Trial (FIT), treatment with alendronate 10 mg/day reduces the risk of vertebral fracture by 48% and increases bone mineral density (BMD) in patients with vertebral fractures. In the Vertebral Efficacy with Risedronate Therapy Multi-National (VERT-MN) and VERT-NA (North America) studies, treatment with risedronate 5 mg/day reduces the risk of vertebral fracture by 49% and 41%, respectively. Risedronate 5 mg daly for 3 years leads to an increase in BMD. The Prevent Recurrence Of Osteoporotic Fractures (PROOF) study has shown a significant decrease in the risk of vertebral fracture in patients treated with calcitonin 200 IU. However, numerous criticisms of the methodology of this study design have been identified. Selective estrogen receptor modulators could act as agonists or antagonists of estrogens, depending on the target tissue. In the Multiple Outcomes of Raloxifene Evaluation (MORE) study, treatment with raloxifene reduces the risk of vertebral fracture by 50% in patients without prevalent vertebral fracture and by 30% in patients with prevalent vertebral fracture. PTH treatment leads to an increase in BMD and reduces the risk of vertebral fracture by 65%. Strontium ranelate has a novel mechanism of action (stimulation of bone synthesis and decrease in bone resorption), and administration of 2 g daily has a proven positive effect, leading to an increase in bone mass among women with osteoporosis. This effect was especially evident in the Spinal Osteoporosis Therapeutic Intervention phase III (SOTI) study, in which a significant decrease in the incidence of vertebral fracture of 41% over 3 years has been shown. Thus, effective therapeutic strategies now enable improved treatment of postmenopausal osteoporosis. However, this condition is still poorly diagnosed and not all patients are correctly treated. Preventing the occurrence of the first fracture should remain the prime concern.