Alendronate - An update of its use in osteoporosis

Alendronate (alendronic acid) is a nitrogen-containing bisphosphonate which binds to bone surfaces and inhibits bone resorption by osteoclasts. Oral alendronate 5 or 10 mg/day produces sustained increases in bone minera l density (BMD) in postmenopausal women with or without osteoporosis, in me n with primary osteoporosis and in both men and women with or without osteo porosis receiving systemic corticosteroid therapy. Histomorphometric analys es have found that alendronate does not appear to impair bone quality. Alen dronate reduced the risk of radiographic vertebral fracture, clinical verte bral fracture or hip fracture by 47 to 56% in postmenopausal women who had greater than or equal to1 existing vertebral fracture and in those with no existing vertebral fractures but who had osteoporosis. In a number of compa rative trials in postmenopausal women with osteoporosis. alendronate 10 mg/ day was found to be more effective at inducing sustained increases in BMD t han intranasal calcitonin, and at least as effective as conjugated estrogen s and raloxifene, Alendronate 70mg administered once weekly and 35mg twice weekly are as effective at increasing BMD as 10 mg/day in this patient grou p. In clinical trials, alendronate was generally well tolerated when taken as recommended. Adverse events tended to be transient and associated with the upper GI tract. most commonly including abdominal pain, nausea, dyspepsia, acid regurgitation and musculoskeletal pain. No statistically significant d ifferences between alendronate 10 mg/day and placebo have been found in the incidence of upper GI adverse events in large clinical trials, However, po stmarketing surveillance reported a low incidence of adverse events related to the oesophagus, Specific instructions aimed at reducing the risk of upp er GI adverse events have been provided by the manufacturer. Conclusions: Alendronate is effective and generally well tolerated in the t reatment of women or men with primary (including postmenopausal) or cortico steroid-induced osteoporosis and in the prevention of osteoporosis in postm enopausal women. The drug has been associated with upper GI tract adverse e vents, although the extent to which alendronate is responsible for these ev ents has not been clearly established. Alendronate should be considered a t reatment of choice in postmenopausal women with osteoporosis. Alendronate i s also a suitable treatment option for primary osteoporosis in men and for corticosteroid-induced osteoporosis in both men and women.