Alendronate in the treatment of Paget's disease of bone

This review reports the results of 2 recently completed long-term, randomis ed, double-blind, multicentre, controlled studies in which men and women wi th moderate to severe Paget's disease received oral alendronate 40 mg daily for 6 months. One study, conducted in the United States, compared the effe cts of alendronate 60 mg/day (n = 41) with those of oral etidronate 400 mg/ day (n = 47); the other, conducted in the United Kingdom, Australia, and Ne w Zealand, compared the effects of alendronate (n = 27) with those of place bo (n = 28). in both studies, alendronate significantly reduced serum conce ntrations of alkaline phosphatase by more than 70%, which was significant i n comparison with baseline (P < 0.001) and the comparator regimens (P < 0.0 01). Response to treatment (i.e. a > 60% decrease in or normalisation of se rum alkaline phosphatase) was seen in more than three-quarters of patients treated with alendronate in both trials, compared with less than one-third of patients treated with etidronate and no patients treated with placebo. R adiologic scores, reflecting the status of osteolytic lesions, improved in a greater proportion of patients receiving alendronate than in those receiv ing etidronate or placebo. Histomorphometric analysis performed at 6 months showed that bone formed during alendronate treatment was of normal qualify , without evidence of impaired mineralisation or other abnormalities. Alend ronate was well tolerated with an adverse event profile comparable with tho se of etidronate and placebo. These studies therefore showed that 6 months of treatment with oral alendronate suppresses disease activity in patients with Paget's disease of bone, with beneficial effects on biochemical, radio logic, and histomorphometric indices superior to those of etidronate and pl acebo.