Effects of Teriparatide in the Treatment of Postmenopausal Women With Osteoporosis

Inclusion Criteria: * Ambulatory, postmenopausal women. * A minimum of either one moderate or two mild atraumatic vertebral fractures, and a minimum of seven evaluable nonfractured vertebrae. * Hip BMD or lumbar spine BMD measurement at least 1.0 standard deviation (SD) below the average bone mass for young, healthy women (T-score) only in patients with fewer than two moderate fractures or in patients previously treated with therapeutic doses of bisphosphonates or fluorides * Normal or clinically nonsignificant abnormal laboratory values (serum calcium, PTH(1-84), \& urine calcium must be within normal limits at baseline; 25-hydroxyvitamin D must be between the lower limit of normal \& 3 times the upper limit of normal at baseline). Exclusion Criteria: * Fractures in areas of bone affected by diseases other than osteoporosis (for example, cancer or Paget's disease). * Satisfactory baseline thoracic and lumbar spinal x-ray views cannot be obtained as determined by the centralized x-ray quality assurance center (for example, severe scoliosis or kyphosis). * Current or recent (within 1 year prior to randomization) metabolic bone disorders other than postmenopausal osteoporosis, such as Paget's disease, renal osteodystrophy, osteomalacia, or any secondary causes of osteoporosis * Current or recent (within 1 year prior to randomization) disease which affects bone metabolism, such as hypoparathyroidism, hyperparathyroidism, or hyperthyroidism. * Currently suspected carcinoma or history of carcinoma in the 5 years prior to randomization. * Nephrolithiasis or urolithiasis in the 2 years prior to randomization. * Current or recent (within 1 year prior to randomization) sprue, inflammatory bowel disease, or malabsorption syndrome, or any indication of poor intestinal absorption of calcium, such as the combination of a low urinary calcium excretion and an elevated serum intact parathyroid hormone level. * Poor medical or psychiatric risk for treatment with an investigational drug, in the opinion of the investigator. * Treatment with androgens or other anabolic steroids in the 6 months prior to randomization. * Treatment with calcitonins in the 2 months prior to randomization. * Treatment with estrogen * Treatment with progestins in the 3 calendar months prior to randomization, or for more than 2 months in the 12 calendar months prior to randomization. * Treatment with corticosteroids. * Treatment with fluorides in the 6 months prior to randomization or for more than 60 days in the 24 months prior to randomization. * Treatment with oral bisphosphonates in the 3 months prior to randomization or for more than 60 days in the 24 months prior to randomization; treatment with intravenous bisphosphonates in the 24 months prior to randomization. * Treatment with vitamin D \>50,000 IU/week, or with any dose of calcitriol, analogs, or agonists in the 6 months prior to randomization. The 25-hydroxyvitamin D laboratory value at randomization must be between the lower limit of normal and three times the upper limit of normal. * Treatment with coumarins and indandione derivatives in the 3 months prior to randomization; treatment with heparins \>10,000 U/day for more than 30 days in the 6 months prior to randomization. * Treatment with calcium- or aluminum-containing antacids * Treatment with any other drug known to affect bone metabolism in the 6 months prior to randomization. * Treatment with any investigational drug during the month prior to the calcium and vitamin D run-in phase. Treatment with investigational drugs in certain therapeutic classes during the month prior to the calcium \& vitamin D run-in phase.