Risedronate: a clinical review.

BACKGROUND: Risedronate sodium has recently been approved for the prevention and treatment of postmenopausal and corticosteroid-induced osteoporosis.
METHODS: Studies of risedronate were obtained from the MEDLINE database (1966 to the present) of references using risedronate, risedronic acid, osteoporosis, and human subject as keywords. Additional references were sought from the reference lists of the articles obtained.
RESULTS: Nine randomized controlled trials and 7 other clinical trials were obtained. In postmenopausal women with normal bone density, risedronate increases lumbar spine bone density and preserves femoral neck density. In postmenopausal women with prior vertebral fracture, risedronate decreases new vertebral and nonvertebral fracture incidence. In patients who experienced breast cancer and who have chemotherapy-induced menopause, risedronate preserves bone. Risedronate prevents vertebral bone loss in patients beginning long-term corticosteroid therapy. Risedronate decreases pagetic bone pain and induces radiological improvement in pagetic lesions. Risedronate induces normalization of biochemical abnormalities and may be more effective than etidronate disodium for Paget disease. Only one study, a trial in patients with postmenopausal osteoporosis using a low dose (2.5 mg) of risedronate, did not have a positive result. Adverse effects in patients with postmenopausal osteoporosis, breast cancer, and Paget disease and in those taking corticosteroids are similar to those of patients taking placebo, and do not include notable upper gastrointestinal tract adverse event rates or serious adverse events.
CONCLUSIONS: Risedronate prevents postmenopausal bone loss, decreases fracture in those with established postmenopausal osteoporosis, effectively treats Paget disease, and prevents corticosteroid-induced bone loss. Long-term toxic effects and efficacy, particularly fracture end point data, are unknown. Also undefined are optimal duration of therapy, potential for use in combination with other agents, and direct comparison with other bisphosphonates used for osteoporosis.