Effect of an intermittent weekly dose of human parathyroid hormone (1-34) on osteoporosis: A randomized double-masked prospective study using three dose levels

To test the effect of amino-terminal peptide 134 of human parathyroid hormo ne (hPTH (1-34)) as a possible bone anabolic agent in the treatment of oste oporosis, weekly subcutaneous injection of 50 units (L group), 100 units (M group) or 200 units (H group) of hPTH (1-34) was started in 220 patients w ith osteoporosis at 71 institutions randomly divided into three groups in a double-masked system. Lumbar spine bone mineral density (BMD) by dual-ener gy X-ray absorptiometry (DXA) increased by 0.6%, 3.6% and 8.1% after 48 wee ks in groups L, M and H respectively, responses in groups M and H being sig nificantly higher than in L (p <0.05, Mann-Whitney U-test). Since the coeff icient of variation for lumbar spine measurement stayed at 1-2.5%, increase s of 3.6% and 8.1% appeared significant. Metacarpal BMD and cortical thickn ess measured by radiogrammetry did not change significantly. Serum calcium decreased in each group and serum phosphorus decreased in groups M and H. U rinary calcium/creatinine decreased at the 12th week in group H and at the 24th and 48th weeks in groups M and L. Serum 25(OH) vitamin D and 1,25(OH)( 2) vitamin D decreased in each group at the 48th week (p <0.05). Serum bone -type alkaline phosphatase was increased at the fourth week in groups H and M and decreased at the 48th week in group H. Urinary hydroxyproline, pyrid inoline and deoxypyridinoline declined significantly in each group. Backach e improved in 30-40% of each group. No serious adverse effects were found d uring the test period. Intermittent weekly injection of hPTH (1-34) increas ed lumbar BMD in osteoporosis, suggesting usefulness in the treatment of os teoporosis.