Effects of ipriflavone on bone mass and calcium metabolism in postmenopausal osteoporosis.

Recently it has been demonstrated that ipriflavone (IP), an isoflavone derivative, is able to increase bone mass in patients with established postmenopausal osteoporosis (PMO). Here we present a preliminary report of a 2-year multicenter, double-blind, placebo-controlled clinical study performed in order to evaluate the efficacy and tolerability of IP in PMO. A large number of patients with PMO, referred to 12 Italian centers, was randomly divided into 2 groups and treated with oral IP (600 mg/day) or placebo (Pl). All patients received an oral Ca supplement (1 g/day). One hundred and twenty six patients completed 1 year of the study. Bone mineral density (BMD) of the distal radius, measured by DPA, serum osteocalcin (BGP), and urinary hydroxyproline excretion (HOP/Cr), were measured before and after 12 months. After 12 months, a significant increase in BMD was observed in the IP-treated group (P < 0.05). IP determined a reduction of HOP/Cr, while in Pl-treated patients a significant increase of this index, as well as of BGP, was observed. After 12 months the difference between the two groups resulted significant (P < 0.05) for BGP. The drug was well tolerated and the patients' compliance to the oral treatment resulted excellent. The results of this study indicate that IP is able to increase bone mass in patients with PMO.