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Background: There is a medical need for therapies that improve hip fracture healing. Teriparatide (Forteo(®)/ Forsteo(®), recombinant human parathyroid hormone) is a bone anabolic drug that is approved for treatment of osteoporosis and glucocorticoid-induced osteoporosis in men and postmenopausal women at high fracture risk. Preclinical and preliminary clinical data also suggest that teriparatide may enhance bone healing.Questions/purposes: We wished to test the hypotheses that treatment with teriparatide versus placebo would improve femoral neck fracture healing after internal fixation as measured by (1) frequency of revision surgery, (2) radiographic fracture healing, and (3) other outcomes including pain control, gait speed, and safety.Methods: We initiated two separate, but identically designed, clinical trials to meet FDA requirements to provide substantial evidence to support approval of a new indication. The two prospective, randomized double-blind, placebo-controlled Phase III studies were designed to evaluate the effect of subcutaneous teriparatide (20 μg/day) for 6 months versus placebo on fracture healing at 24 months. The trials were conducted concurrently with a planned enrollment of 1220 patients per trial. However, enrollment was stopped owing to very slow patient accrual, and an a priori decision was made to pool the results of those studies for statistical analyses before study completion; pooling was specified in both protocols. Randomization was stratified by fixation (sliding hip screw or multiple cancellous screws) and fracture type (displaced or nondisplaced). An independent Central Adjudication Committee reviewed revision surgical procedures and radiographs. A total of 159 patients were randomized in the two trials (81 placebo, 78 teriparatide). The combined program had very low power to detect the originally expected treatment effect but had approximately 80% power to detect a larger difference of 12% between treatment groups for risk of revision surgery.Results: The proportion of patients undergoing revision surgery at 12 months was 14% (11 of 81) in the placebo group versus 17% (13 of 78) in the teriparatide group. Central Adjudication Committee review excluded two of these patients treated with placebo from the primary analysis. After exclusions, the proportion of patients who did not undergo revision surgery at 12 months (primary endpoint) was not different between the study and placebo groups, at 88% in the placebo group (90% CI, 0.79-0.93) versus 84% in the teriparatide group (90% CI, 0.75-0.90; p = 0.743). There also were no differences between groups in the proportion of patients achieving radiographic fracture healing at 12 months (75% [61 of 81] placebo versus 73% [57 of 78] teriparatide; odds ratio, 0.89; 90% CI, 0.46-1.72; p = 0.692) or in measures of pain control (such as pain during ambulation, 92% [55 of 62] placebo versus 91% [52 of 57] teriparatide; odds ratio, 0.91; 90% CI, 0.25-3.37; p = 0.681). The frequency of patients reporting adverse events was 49% [40 of 81] in the placebo group versus 45% [35 of 78] in the teriparatide group (p = 0.634) during the 6-month treatment period.Conclusions: The small sample size limited this study's power to detect potential differences, and the results are exploratory. With the patients available, teriparatide did not decrease the risk of revision surgery, improve radiographic signs of fracture healing, or decrease pain compared with the placebo. The adverse event data observed were consistent with the teriparatide safety profile. Functional and health outcome data from the studies may help improve our understanding of patients recovering from femoral neck fractures. Further large controlled studies are required to determine the effect of teriparatide on fracture healing.Level Of Evidence: Level II, prospective study. [ABSTRACT FROM AUTHOR]

Background: Vertebral fractures increase the risk of new vertebral fractures; however, we are not aware of any study addressing the risk of new vertebral fractures adjacent to existing vertebral fractures. Therefore, we sought to determine the influence of the number and severity of prevalent (preexisting) vertebral fractures on the risk of new adjacent vertebral fractures and to determine whether teriparatide (rhPTH [recombinant human parathyroid hormone] [1-34]) or raloxifene treatment reduces the incidence of adjacent vertebral fractures in postmenopausal women with osteoporosis.Methods: Data from the Fracture Prevention Trial and the Multiple Outcomes of Raloxifene Evaluation trial were analyzed to determine the incidences of new adjacent and new nonadjacent vertebral fractures in the placebo groups and the effect of treatment with raloxifene and teriparatide on the incidence of new adjacent vertebral fractures as compared with that of new nonadjacent vertebral fractures.Results: Of 1226 untreated postmenopausal women with one or more prevalent vertebral fractures at baseline, 196 (16.0%) had a total of 292 new vertebral fractures during the two-year follow-up period, with 108 (8.8%) of the 1226 women having at least one new fracture adjacent to a prevalent fracture. Of the 292 new vertebral fractures, 136 (47%) were adjacent to a previously existing vertebral fracture. The risk of a new adjacent vertebral fracture was 2.5-fold higher than the risk of a new nonadjacent vertebral fracture (4.03% compared with 1.59%). The incidence of new adjacent vertebral fractures increased with both the number and the severity of prevalent vertebral fractures. Teriparatide reduced the risk of any new, new adjacent, and new nonadjacent vertebral fractures by 72%, 75%, and 70%, respectively, compared with the rates in the placebo group. Similarly, compared with the placebo, raloxifene treatment reduced the risk of any new vertebral fracture, new adjacent vertebral fracture, and new nonadjacent vertebral fracture by 54%, 54%, and 53%, respectively.Conclusions: In untreated postmenopausal women with osteoporosis, nearly half of the incident vertebral fractures occur adjacent to an existing vertebral fracture. Both teriparatide and raloxifene can significantly reduce the occurrence of new adjacent and nonadjacent vertebral fractures. [ABSTRACT FROM AUTHOR]

Osteoporosis increases fracture risk, especially in metaphyseal bone. Fractures seriously impair function and quality of life and incur large direct and indirect costs. Although the prevention of fractures is certainly the option, a fast and uneventful healing process is optimal when fractures do occur. Many new therapeutic strategies have been developed to accelerate fracture-healing or to diminish the complication rate during the course of fracture-healing. However, widely accepted guidelines are needed to demonstrate the positive or negative interactions of bioactive substances, drugs, and other agents that are being used to promote fracture-healing. For each study design, the primary study goal should be indicated. Outcome variables should include both objective and subjective parameters. The guidelines should be harmonized between European and American regulatory authorities to ensure comparability of results of studies and to foster global harmonization of regulatory requirements. [ABSTRACT FROM AUTHOR]

Background: Recombinant human parathyroid hormone (PTH [1-34]; teriparatide) is a new treatment for postmenopausal osteoporosis that can be systemically administered for the primary purpose of increasing bone formation. Because several studies have described the enhancement of fracture-healing and osteointegration in animals after use of PTH, we sought to critically analyze this skeletal effect.Methods: Two hundred and seventy male Sprague-Dawley rats underwent standard, closed femoral fractures and were divided into three groups that were administered daily subcutaneous injections of 5 or 30 mug/kg of PTH (1-34) or vehicle (control). The dosing was administered for up to thirty-five days. Groups were further divided into three subgroups and were killed on day 21, 35, or 84 after the fracture. The bones were subjected to mechanical torsion testing, histomorphometric analysis, or microquantitative computed tomography.Results: By day 21, calluses from the group treated with 30 mug of PTH showed significant increases over the controls with respect to torsional strength, stiffness, bone mineral content, bone mineral density, and cartilage volume. By day 35, both groups treated with PTH showed significant increases in bone mineral content and density and total osseous tissue volume, and they demonstrated significant decreases in void space and cartilage volume (p < 0.05). Torsional strength was significantly increased at this time-point in the group treated with 30 mug of PTH (p < 0.05). While dosing was discontinued on day 35, analyses performed after eighty-four days in the group treated with 30 mug of PTH showed sustained increases over the controls with respect to torsional strength and bone mineral density. No change was noted in osteoclast density at the time-points measured, suggesting that treatment with PTH enhanced bone formation but did not induce bone resorption.Conclusions: These data show that daily systemic administration of PTH (1-34) enhances fracture-healing by increasing bone mineral content and density and strength, and it produces a sustained anabolic effect throughout the remodeling phase of fracture-healing. [ABSTRACT FROM AUTHOR]