Effects of intravenous zoledronic acid plus subcutaneous teriparatide [rhPTH(1-34)] in postmenopausal osteoporosis

Intermittent Parathyroid Hormone Accelerates Stress Fracture Healing More Effectively Following Cessation of Bisphosphonate Treatment

Parathyroid hormone (PTH) and bisphosphonates (BPs), including alendronate (ALN), have opposing effects on bone dynamics. The extent to which PTH remains effective in the treatment of stress fracture (SFx) in the presence of an ongoing BP treatment has not been tested. SFx was induced in 150 female Wistar rats, divided into five equal groups (n = 30). All rats were pretreated with ALN (1 μg/kg^-1/day^-1) for 14 days prior to SFx induction, followed by ALN cessation or continuation for the duration of the experiment; this was combined with daily PTH (8 μg/100 g^-1/day^-1) on SFx induction for 14 days, followed by cessation or continuation of ALN after SFx induction or an equivalent vehicle as a control. Ulnas were examined 2 weeks or 6 weeks following SFx. Two toluidine blue- and two tartrate-resistant acid phosphatase-stained sections were examined for histomorphometric analysis using Osteomeasure software. There was a significant interaction between the effects of time and treatment type on the woven bone width and apposition rate, as well as an improvement in the woven bone architecture. However, woven bone variables remained unaffected by the cessation or continuation of ALN. Cessation of ALN increased osteoclast number when compared with the ALN-PTH continuation group (p = 0.006), and vehicle (p = 0.024) after 2 weeks. There was a significant interaction between the effects of time and treatment type on the number of osteoclasts per unit BMU area and length. The number of osteoclasts per unit BMU area and length was significantly greater in ALN cessation groups. It was concluded that intermittent short-duration iPTH treatment effectively increased remodeling of SFx with a concurrent BP treatment, provided that BP was ceased at the time of SFx. Our results could help develop shorter iPTH treatment protocols for the clinical management of SFxs and guide clinical decision-making to cease BP treatment in cases of SFx. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Treatment of postmenopausal osteoporosis with bone-forming and antiresorptive treatments: Combined and sequential approaches

Efficient therapies are available for the treatment of osteoporosis. Bisphosphonates and denosumab are the most commonly used antiresorptive therapies. Despite differences in the increase in bone mineral density seen with these drugs, the reductions in fracture risk are similar; 50-70%, 20%, and 40% for vertebral, non-vertebral and hip fractures, respectively. The bone-forming treatments; teriparatide and abaloparatide increase bone mineral density more than the antiresorptives and the reductions in fracture risk are 85% and 40-50% for vertebral and non-vertebral fractures, respectively, compared to placebo. The VERO study demonstrated a >50% reduction in vertebral and clinical fractures in women treated with teriparatide compared to risedronate. The dual-action treatment; romosozumab leads to more pronounced increases in BMD than other treatment modalities and reduces the risk of vertebral and clinical fractures by 73% and 36% compared to placebo after 12 months and the sequential treatment regime; romosozumab for 12 months followed by alendronate reduced the risk of vertebral, non-vertebral and hip fractures by 48%, 20% and 38%, respectively compared to alendronate after 2-3 years. The evidence for combination therapy targeting both resorption and formation is limited as only short-term studies with BMD as the endpoint have been performed. All bone-forming and dual-action treatments increase BMD and reduce the fracture risk, however, the effect wears off with time and treatment is therefore only temporary and should be followed by antiresorptive treatment with a bisphosphonate or denosumab. The sequence of treatment matters as the BMD response to teriparatide is reduced in patients previously treated with bisphosphonates; however, based on the findings of the VERO trial, the anti-fracture efficacy of bone-forming treatment in comparison with risedronate seems to be preserved after bisphosphonate therapy. The DATA study suggested that transitioning from denosumab to teriparatide is problematic due to the increase in bone resorption occurring after stopping denosumab. Studies have shown further improvements in BMD when transitioning from oral bisphosphonates to zoledronic acid or denosumab. Management of osteoporosis will in many patients include a long-term treatment plan. This will often include sequential therapy which in severe cases preferably should start with bone-forming followed by antiresorptive treatment. The severity of osteoporosis, reaching a treatment goal, and responding to treatment failure are important factors determining the treatment sequence in the individual patient.

High fracture risk patients with glucocorticoid-induced osteoporosis should get an anabolic treatment first

Long-term glucocorticoid (GC) therapy induces glucocorticoid-induced osteoporosis (GIOP) and its associated fractures. Most specialty organizations recommend bisphosphonates as first-line therapies based only on bone mineral density efficacy data. Effective treatment of GIOP based on head-to-head trials with fracture endpoint has not yet been established. The pathophysiologic mechanisms of GIOP that lead to the detrimental effects on bone are not yet fully elucidated. Although GCs in an early and transitory period promote osteoclastic activity, in the current paper, we outline why GIOP is in fact a disease of the bone formation and then provide the rationale for the use of bone-forming agents as first-line therapy for patients with high fracture risk in GIOP.

Bisphosphonates and parathyroid hormone analogs for improving bone quality in spinal fusion: State of evidence

Spinal fusion is among the most commonly performed surgical procedures for elderly patients with spinal disorders - including degenerative disc disease with spondylolisthesis, deformities, and trauma. With the large increase in the aging population and the prevalence of osteoporosis, the number of elderly osteoporotic patients needing spinal fusion has risen dramatically. Due to reduced bone quality, postoperative complications such as implant failures, fractures, post-junctional kyphosis, and pseudarthrosis are more commonly seen after spinal fusion in osteoporotic patients. Therefore, pharmacologic treatment strategies to improve bone quality are commonly pursued in osteoporotic cases before conducting spinal fusions. The two most commonly used pharmacotherapeutics are bisphosphonates and parathyroid hormone (PTH) analogs. Evidence indicates that using bisphosphonates and PTH analogs, alone or in combination, in osteoporotic patients undergoing spinal fusion, decreases complication rates and improves clinical outcomes. Further studies are needed to develop guidelines for the administration of bisphosphonates and PTH analogs in osteoporotic spinal fusion patients in terms of treatment duration, potential benefits of sequential use, and the selection of either therapeutic agents based on patient characteristics.

Zoledronate

Zoledronate is the most potent and most long-acting bisphosphonate in clinical use, and is administered as an intravenous infusion. Its major uses are in osteoporosis, Paget's disease, and in myeloma and cancers to reduce adverse skeletal related events (SREs). In benign disease, it is a first- or second-line treatment for osteoporosis, achieving anti-fracture efficacy comparable to that of the RANKL blocker, denosumab, over 3 years, and it reduces fracture risk in osteopenic older women. It is the preferred treatment for Paget's disease, achieving higher rates of remissions which are much more prolonged than with any other agent. Some trials have suggested that it reduces mortality, cardiovascular disease and cancer, but these findings are not consistent across all studies. It is nephrotoxic, so should not be given to those with significant renal impairment, and, like other potent anti-resorptive agents, can cause hypocalcemia in patients with severe vitamin D deficiency, which should be corrected before administration. Its most common adverse effect is the acute phase response, seen in 30-40% of patients after their first dose, and much less commonly subsequently. Clinical trials in osteoporosis have not demonstrated increases in osteonecrosis of the jaw or in atypical femoral fractures. Observational databases are currently inadequate to determine whether these problems are increased in zoledronate users. Now available as a generic, zoledronate is a cost-effective agent for fracture prevention and for management of Paget's disease, but wider provision of infusion facilities is important to increase patient access. There is a need to further explore its potential for reducing cancer, cardiovascular disease and mortality, since these effects could be substantially more important than its skeletal actions.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS/AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS-2020 UPDATE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPGs). Methods: Recommendations are based on diligent reviews of the clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2020 updated guideline contains 52 recommendations: 21 Grade A (40%), 24 Grade B (46%), 7 Grade C (14%), and no Grade D (0%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 368 citations: 123 (33.5%) evidence level (EL) 1 (highest), 132 (36%) EL 2 (intermediate), 20 (5.5%) EL 3 (weak), and 93 (25%) EL 4 (lowest). New or updated topics in this CPG include: clarification of the diagnosis of osteoporosis, stratification of the patient according to high-risk and very-high-risk features, a new dual-action therapy option, and transitions from therapeutic options. Conclusion: This guideline is a practical tool for endocrinologists, physicians in general, regulatory bodies, health-related organizations, and interested laypersons regarding the diagnosis, evaluation, and treatment of post-menopausal osteoporosis. Abbreviations: 25(OH)D = 25-hydroxyvitamin D; AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AFF = atypical femoral fracture; ASBMR = American Society for Bone and Mineral Research; BEL = best evidence level; BMD = bone mineral density; BTM = bone turnover marker; CI = confidence interval; CPG = clinical practice guideline; CTX = C-terminal telopeptide type-I collagen; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = U.S. Food and Drug Administration; FRAX® = Fracture Risk Assessment Tool; GI = gastrointestinal; HORIZON = Health Outcomes and Reduced Incidence with Zoledronic acid ONce yearly Pivotal Fracture Trial (zoledronic acid and zoledronate are equivalent terms); ISCD = International Society for Clinical Densitometry; IU = international units; IV = intravenous; LSC = least significant change; NOF = National Osteoporosis Foundation; ONJ = osteonecrosis of the jaw; PINP = serum amino-terminal propeptide of type-I collagen; PTH = parathyroid hormone; R = recommendation; ROI = region of interest; RR = relative risk; SD = standard deviation; TBS = trabecular bone score; VFA = vertebral fracture assessment; WHO = World Health Organization.

Denosumab, raloxifene, romosozumab and teriparatide to prevent osteoporotic fragility fractures: a systematic review and economic evaluation

BACKGROUND

Fragility fractures are fractures that result from mechanical forces that would not ordinarily result in fracture.

OBJECTIVES

The objectives were to evaluate the clinical effectiveness, safety and cost-effectiveness of non-bisphosphonates {denosumab [Prolia®; Amgen Inc., Thousand Oaks, CA, USA], raloxifene [Evista®; Daiichi Sankyo Company, Ltd, Tokyo, Japan], romosozumab [Evenity®; Union Chimique Belge (UCB) S.A. (Brussels, Belgium) and Amgen Inc.] and teriparatide [Forsteo®; Eli Lilly and Company, Indianapolis, IN, USA]}, compared with each other, bisphosphonates or no treatment, for the prevention of fragility fracture.

DATA SOURCES

For the clinical effectiveness review, nine electronic databases (including MEDLINE, EMBASE and the World Health Organization International Clinical Trials Registry Platform) were searched up to July 2018.

REVIEW METHODS

A systematic review and network meta-analysis of fracture and femoral neck bone mineral density were conducted. A review of published economic analyses was undertaken and a model previously used to evaluate bisphosphonates was adapted. Discrete event simulation was used to estimate lifetime costs and quality-adjusted life-years for a simulated cohort of patients with heterogeneous characteristics. This was done for each non-bisphosphonate treatment, a strategy of no treatment, and the five bisphosphonate treatments previously evaluated. The model was populated with effectiveness evidence from the systematic review and network meta-analysis. All other parameters were estimated from published sources. An NHS and Personal Social Services perspective was taken, and costs and benefits were discounted at 3.5% per annum. Fracture risk was estimated from patient characteristics using the QFracture® (QFracture-2012 open source revision 38, Clinrisk Ltd, Leeds, UK) and FRAX® (web version 3.9, University of Sheffield, Sheffield, UK) tools. The relationship between fracture risk and incremental net monetary benefit was estimated using non-parametric regression. A probabilistic sensitivity analysis and scenario analyses were used to assess uncertainty.

RESULTS

Fifty-two randomised controlled trials of non-bisphosphonates were included in the clinical effectiveness systematic review and an additional 51 randomised controlled trials of bisphosphonates were included in the network meta-analysis. All treatments had beneficial effects compared with placebo for vertebral, non-vertebral and hip fractures, with hazard ratios varying from 0.23 to 0.94, depending on treatment and fracture type. The effects on vertebral fractures and the percentage change in bone mineral density were statistically significant for all treatments. The rate of serious adverse events varied across trials (0-33%), with most between-group differences not being statistically significant for comparisons with placebo/no active treatment, non-bisphosphonates or bisphosphonates. The incremental cost-effectiveness ratios were > £20,000 per quality-adjusted life-year for all non-bisphosphonate interventions compared with no treatment across the range of QFracture and FRAX scores expected in the population eligible for fracture risk assessment. The incremental cost-effectiveness ratio for denosumab may fall below £30,000 per quality-adjusted life-year at very high levels of risk or for high-risk patients with specific characteristics. Raloxifene was dominated by no treatment (resulted in fewer quality-adjusted life-years) in most risk categories.

LIMITATIONS

The incremental cost-effectiveness ratios are uncertain for very high-risk patients.

CONCLUSIONS

Non-bisphosphonates are effective in preventing fragility fractures, but the incremental cost-effectiveness ratios are generally greater than the commonly applied threshold of £20,000-30,000 per quality-adjusted life-year.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42018107651.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 29. See the NIHR Journals Library website for further project information.

Comparison between teriparatide and bisphosphonates for improving bone mineral density in postmenopausal osteoporosis patients: A meta-analysis

BACKGROUND

We performed a systematic review and meta-analysis of the efficacy and safety of teriparatide and bisphosphonates in managing postmenopausal osteoporosis.

METHODS

PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure were searched for relevant randomized controlled trials that were published before April 2018 and compared teriparatide and bisphosphonates in treating postmenopausal osteoporosis. Stata 12.0 was used for the meta-analysis. The pooled risk ratio (RR) or weighted mean difference and 95% confidence interval (CI) were calculated using a fixed effects or random effects meta-analysis.

RESULTS

A total of 14 randomized controlled trials were included in this meta-analysis. The teriparatide group was associated with a lower total occurrence of vertebral fractures (RR = 0.55, 95% CI: 0.40-0.77; P = .001) and nonvertebral fractures (RR = 0.65, 95% CI: 0.46-0.90; P = .009) than the bisphosphonate group. Moreover, compared with the bisphosphonate group, the teriparatide group had improved bone mineral density at the lumbar spine and femoral neck at the final follow-up (P < .05). There was no significant difference between the teriparatide and bisphosphonate groups in terms of complications (RR = 1.05, 95% CI: 0.90, 1.22, P = .516).

CONCLUSIONS

Teriparatide significantly reduced the occurrence of vertebral and nonvertebral fractures in osteoporosis patients. More studies should focus on the quality of life of patients using these 2 drugs.

Overview of treatment approaches to osteoporosis

Efficient therapies are available for the treatment of osteoporosis. Anti-resorptive therapies, including bisphosphonates and denosumab, increase bone mineral density (BMD) and reduce the risk of fractures by 20-70%. Bone-forming or dual-action treatments stimulate bone formation and increase BMD more than the anti-resorptive therapies. Two studies have demonstrated that these treatments are superior to anti-resorptives in preventing fractures in patients with severe osteoporosis. Bone-forming or dual-action treatments should be followed by anti-resorptive treatment to maintain the fracture risk reduction. The BMD gains seen with bone-forming and dual-action treatments are greater in treatment-naïve patients compared to patients pretreated with anti-resorptive treatments. However, the antifracture efficacy seems to be preserved. Treatment failure will often lead to switch of treatment from orally to parentally administrated anti-resorptives treatment or from anti-resorptive to bone-forming or dual-action treatment. Osteoporosis is a chronic condition and therefore needs a long-term management plan with a personalized approach to treatment. LINKED ARTICLES: This article is part of a themed issue on The molecular pharmacology of bone and cancer-related bone diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.9/issuetoc.

No evidence for alteration in early secondary mineralization by either alendronate, teriparatide or combination of both in transiliac bone biopsy samples from postmenopausal osteoporotic patients

The influence of treatment with alendronate (ALN), teriparatide (TPTD) or concurrent treatment with both on the human bone matrix mineralization has not yet been fully elucidated. For this purpose we analyzed quadruple fluorochrome labelled transiliac bone biopsy samples (n = 66) from postmenopausal osteoporotic women with prior and ongoing ALN (ALN-Rx arm) or without ALN (Rx-Naïve arm) after 7 months treatment with cyclic or daily TPTD or without TPTD using quantitative backscattered electron imaging and confocal scanning laser microscopy. Additionally to the bone mineralization density distribution (BMDD) of entire cancellous and cortical compartments, we measured the mineralization kinetics, i.e. the calcium concentration between the younger (Ca_DL2) and older double labels (Ca_DL1), and in interstitial bone (Ca_int) in a subset of the biopsy cohort.

We found the BMDD from the patients with prior and ongoing ALN generally shifted to higher calcium concentrations compared to those without ALN (average degree of mineralization in cancellous bone Cn.CaMean + 3.1%, p<0.001). The typical BMDD changes expected by cyclic or daily TPTD treatment due to the increased bone turnover/formation, e.g. an increase in low mineralized bone area were not observed. Additionally, we found no influence of treatment with ALN or TPTD or combination thereof on Ca_DL2, Ca_DL1, or Ca_int. Pooling the information from all groups, Ca_DL1 was +5.9% (p<0.001) higher compared to Ca_DL2, corresponding to a mineralization rate of 0.18 wt% Ca per week during the early secondary mineralization process.

Our data suggest that the patients in the ALN-Rx arm had more highly mineralized bone matrix than those without ALN due to their lower bone turnover. The reason for the unexpected BMDD findings in the TPTD treated remain unknown and cannot be attributed to altered mineralization kinetics as no differences in the time course of early secondary mineralization were observed between the treatment groups.

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Quadruple fluorescence labeling provided analysis of early secondary bone mineralization rate in osteoporotic patients.

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Alendronate, teriparatide or combination of both had no influence on early secondary bone mineralization in patients.

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The early secondary mineralization rate (increase in mineral content with time) was found to be 0.18 wt% Ca per week.

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Patients in the ALN-Rx arm had higher average bone matrix mineralization than the patients in the Rx-naïve arm.

Emerging therapeutic targets for osteoporosis

Introduction: Osteoporosis is a chronic, skeletal disorder characterized by compromised bone strength and increased fracture risk; it affects 50% of women and 20% of men. In the past two decades, there have been substantial improvements in the pharmacotherapy of osteoporosis which have yielded potent inhibitors of bone resorption or stimulators of bone formation.Areas covered: This review discusses newly identified targets and pathways and conceptual approaches to the prevention of multiple age-related disorders. Furthermore, it summarizes existing therapeutic strategies for osteoporosis.Expert opinion: Our enhanced understanding of bone biology and the reciprocal interactions between bone and other tissues have allowed the identification of new targets that may facilitate the development of novel drugs. These drugs will hopefully achieve the uncoupling of bone formation from resorption and possibly exert a dual anabolic and antiresorptive effect on bone. Alas, limitations regarding adherence, efficacy on nonvertebral fracture prevention and the long-term adverse events still exist for currently available therapeutics. Moreover, the efficacy of most agents is limited by the tight coupling of osteoblasts and osteoclasts; hence the reduction of bone resorption invariably reduces bone formation, and vice versa. This field is very much 'a work in progress.'

Standard Versus Cyclic Teriparatide and Denosumab Treatment for Osteoporosis: A Randomized Trial

In the absence of an intervening antiresorptive agent, cyclic administration of teriparatide does not increase bone mineral density (BMD) more than standard daily therapy. Because denosumab is a potent antiresorptive agent with a rapid off-effect, we hypothesized that it might be the optimal agent to help maximize bone gains with cyclic teriparatide. In this 3-year protocol, 70 postmenopausal women with osteoporosis were randomized to 18 months of teriparatide followed by 18 months of denosumab (standard) or three separate 12-month cycles of 6 months of teriparatide followed by 6 months of denosumab (cyclic). BMD (dual-energy X-ray absorptiometry [DXA]) measurements of lumbar spine (LS), total hip (TH), femoral neck (FN), and 1/3 radius (RAD) were performed every 6 months and total body bone mineral (TBBM) at 18 and 36 months. Baseline descriptive characteristics did not differ between groups except for a minimal difference in LS BMD but not T-score (mean age 65 years, mean LS T-score - 2.7). In the standard group, BMD increments at 36 months were: LS 16%, TH 4%, FN 3%, and TBBM 4.8% (all p < 0.001 versus baseline). In the cyclic group, 36-month BMD increments were similar: LS 12%, TH 4%, FN 4%, and TBBM 4.1% (all p < 0.001 versus baseline). At 36 months, the LS BMD increase with standard was slightly larger than with cyclic (p = 0.04), but at 18 months, in the cyclic group, there was no decline in RAD or TBBM (p = 0.007 and < 0.001, respectively, versus standard). Although the cyclic regimen did not improve BMD compared with standard at 36 months, there appeared to be a benefit at 18 months, especially in the highly cortical skeletal sites. This could be clinically relevant in patients at high imminent risk of fracture, particularly at nonvertebral sites. © 2019 American Society for Bone and Mineral Research. © 2019 American Society for Bone and Mineral Research.

The crisis of inadequate treatment in osteoporosis

The number of fractures related to osteoporosis is expected to increase dramatically in the next few decades because of an increase in the number of elderly patients at high risk of falls and fractures. Developments in the diagnosis and treatment of osteoporosis might change our strategies for management of patients with osteoporosis: the imminent risk of fracture concept, the issue of how to correctly sequence treatment, the potential effectiveness of screening, and goal-directed treatment strategies. Despite advances, few patients receive appropriate treatment for osteoporosis, even after a fracture. The crisis in the treatment of osteoporosis is related to several factors, including the fears and beliefs that patients and physicians have about the adverse effects of treatments. Strategies to address this crisis pose a considerable challenge; nonetheless, prevention of fragility fractures is within our reach. To that end, careful selection of patients at high risk of fracture, selection of the best therapeutic strategy, and accurate communication about fracture risk and bone fragility must be improved.

Combination and sequential treatment in women with postmenopausal osteoporosis

Introduction: Since postmenopausal osteoporosis is a chronic, potentially disabling condition requiring long-term treatment, the physician is expected to decide the optimal treatment strategy, e.g. how to use the available osteoanabolic and antiresorptive agents, sequentially or in combination, in the most effective and safe way, based on personalized patient care.Areas covered: Herein, the authors outline clinical data regarding the efficacy and safety of various sequential treatment strategies. More specifically, they compare the efficacy of osteoanabolic agents when they precede or follow antiresorptive treatment, as well as the efficacy of antiresorptives following other antiresorptives. Finally, the authors quote and discuss available evidence regarding the efficacy and safety of the co-administration of osteoanabolics and antiresorptives in comparison with monotherapies.Expert opinion: Initiation with an osteoanabolic agent followed by an antiresorptive seems to be the optimal treatment sequence, at least in patients with severe osteoporosis. Osteoanabolic treatment following antiresorptives seems to lead in more modest responses in bone mineral density (BMD) and bone turnover markers. Combination therapy with teriparatide and denosumab or zoledronate has achieved higher BMD gains compared to each agent alone; however, due to the high cost, combination therapy is rarely compensated. On the contrary, the combination of teriparatide with alendronate results in smaller BMD increases than TPTD monotherapy.

Pharmacological Therapy of Osteoporosis: What's New?

Osteoporosis and fragility fractures are relevant health issues because of their impact in terms of morbidity, mortality, and socioeconomic burden. Despite this alarming scenario, both underdiagnosis and undertreatment are common features of osteoporotic patients, particularly those who have already sustained a fragility fracture. Pharmacotherapy of osteoporosis is the main treatment option for these patients because of strong evidence about the efficacy of available drugs targeting bone metabolism. However, several issues can interfere with the effectiveness of anti-osteoporotic drugs in clinical practice, such as lack of awareness of both healthcare providers and patients, poor adherence to therapy, and safety in long-term treatment. Therefore, new therapeutic strategies have been proposed to overcome these problems, such as sequential therapy or emerging molecules mainly targeting the stimulation of bone formation. In particular, abaloparatide has been demonstrated to reduce major nonvertebral fracture risk compared with both placebo and teriparatide, although the European Medicines Agency (EMA) refused the marketing authorization because the benefits of this drug did not outweigh its risks. On the other side, EMA has recently approved romosozumab, a monoclonal antibody directed against sclerostin and the only available therapeutic option targeting Wnt signaling, as both bone-forming and antiresorptive intervention to treat osteoporosis and fragility fractures.

Reduced Bone Modeling and Unbalanced Bone Remodeling: Targets for Antiresorptive and Anabolic Therapy

Bone loss during advancing age is the net result of reduced modeling-based bone formation upon the outer (periosteal) envelope and unbalanced remodeling by basic multicellular units (BMUs) upon the three (intracortical, endocortical, and trabecular) components of the inner (endosteal) bone envelope. Each BMU deposits less bone than resorbed, reducing total bone volume and deteriorating the microstructure of the diminished residual bone volume.Antiresorptive agents like bisphosphonates reduce, but do not abolish, the rate of bone remodeling - fewer BMUs remodel, "turn over," the volume of bone. Residual unbalanced remodeling continues to slowly reduce total bone volume and deteriorate bone microstructure. By contrast, denosumab virtually abolishes remodeling so the decrease in bone volume and the deterioration in microstructure cease. The less remodeled matrix remains, leaving more time to complete the slow process of secondary mineralization which reduces the heterogeneity of matrix mineralization and allows it to become glycosylated, changes that may make the smaller and microstructurally deteriorated bone volume more brittle. Neither class of antiresorptive restores bone volume or its microstructure, despite increases in bone mineral density misleadingly suggesting otherwise. Nevertheless, these agents reduce vertebral and hip fractures by 50-60% but only reduce nonvertebral fractures by 20-30%.Restoring bone volume, microstructure, and material composition, "curing" bone fragility, may be partly achieved using anabolic therapy. Teriparatide, and probably abaloparatide, produce mainly remodeling-based bone formation by acting on BMUs existing in their resorption, reversal, or formation phase at the time of treatment and by promoting bone formation in newly initiated BMUs. Romosozumab produces modeling-based bone formation almost exclusively and decreases the surface extent of bone resorption. All three anabolic agents reduce vertebral fracture risk relative to untreated controls; parathyroid hormone 1-34 and romosozumab reduce vertebral fracture risk more greatly than risedronate or alendronate, respectively. Evidence for nonvertebral or hip fracture risk reduction relative to untreated or antiresorptive-treated controls is lacking or inconsistent. Only one study suggests sequential romosozumab followed by alendronate reduces vertebral, nonvertebral, and hip fracture risk compared to continuous alendronate alone. Whether combined antiresorptive and anabolic therapy result in superior fracture risk reduction than monotherapy is untested.

Update on the safety and efficacy of teriparatide in the treatment of osteoporosis

Following the completion of the Fracture Prevention Trial, teriparatide was approved by the United States Food and Drug Administration and the European Medicine Agency as the first therapeutic anabolic agent for the treatment of postmenopausal women with severe osteoporosis. It subsequently received additional approval for the treatment of osteoporosis in men, and for the treatment of osteoporosis associated with glucocorticoid therapy in men and women at risk of fracture. In this review, we summarize the most important data concerning PTH 1-34 therapy before 2016 in the treatment of osteoporosis, and report some outstanding results published in the last 2 years. New data on safety will also discussed, together with the state of art of nonclassical utilization. Finally, in view of the recent approval of biosimilars, possible future landscapes are discussed.

Andrographolide stimulates osteoblastogenesis and bone formation by inhibiting nuclear factor kappa-Β signaling both in vivo and in vitro

Osteoporosis is a bone disease that is associated with a decrease in bone mineral density, deterioration of bone microarchitecture and increased fracture risk. Currently, available treatments mainly focus on either inhibiting osteoclast function, such as administration of bisphosphonate, calcitonin, oestrogen, selective oestrogen receptor modulator and so on, or stimulating osteoblasts, such as parathyroid hormone, to improve bone mass and skeletal microarchitecture. However, there is no option that is completely satisfactory because of the limitations of monotherapy with either class. Thus, it is highly appealing to investigate novel drugs with both antiresorptive and osteoanabolic activities that have the potential to be more beneficial than monotherapy because of the different mechanism of action. As has been proven in previous study that andrographolide (AP), as a key herbal medicine, could suppress osteoclast formation and function both in vivo and in vitro. The purpose of this present study was to identify the effect of AP on osteoblast differentiation and oestrogen deficiency-induced osteoporosis. It was concluded that AP significantly reduced oestrogen deficiency-induced bone loss in vivo. Furthermore, it was proved that tumor necrosis factor alpha severely impaired bone morphogenetic protein-2 (BMP-2)-induced osteoblast differentiation, and this inhibition could be greatly attenuated by AP. This was further supported by the fact that AP significantly increases the expression of osteoblast-specific markers, including runt-related transcription factor-2, osteocalcin and osteopontin. In addition, molecular analysis revealed that AP greatly ceased tumor necrosis factor alpha-mediated stimulation of nuclear factor kappa-Β activity, whereas overexpression of the nuclear factor kappa-Β subunit p65 reversed the stimulatory effects of AP on osteoblast differentiation. Thus, combined with previous study, AP was demonstrated to be a novel agent with both antiresorptive and osteoanabolic activities and had the potential to be developed as an antiosteoporosis alternative.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

This study provides strong evidence for the identification that AP has both antiresorptive and osteoanabolic activities and thus has great potential to be developed as a novel antiosteoporosis agent.

Combination denosumab and high dose teriparatide for postmenopausal osteoporosis (DATA-HD): a randomised, controlled phase 4 trial

BACKGROUND

In the Denosumab and Teriparatide Administration (DATA) study, we showed that denosumab fully inhibits teriparatide-induced bone resorption while allowing for continued teriparatide-induced bone formation, resulting in larger increases in hip and spine bone mineral density (BMD) than with either drug alone. We aimed to assess whether administration of denosumab with high dose teriparatide would stimulate larger increases in bone mass than those observed in the DATA study.

METHODS

DATA-HD was an open-label, randomised, controlled phase 4 trial done at Massachusetts General Hospital. Eligible women were postmenopausal women (at least 36 months since last menses or since hysterectomy with a follicle-stimulating hormone concentration of ≥40 U/L) with osteoporosis. Participants were randomly assigned (1:1) to receive teriparatide 20 μg (standard dose) or 40 μg (high dose) daily via subcutaneous injection for 9 months. At 3 months, both groups were started on denosumab 60 mg every 6 months via subcutaneous injection for 12 months. Areal BMD (aBMD) was measured at 0, 3, 9, and 15 months. Treatment was given open label, but outcome assessors were masked. The primary endpoint was percentage change from baseline in spine areal BMD (aBMD) at 15 months. Women who completed at least one study visit after baseline were included in the modified intention-to-treat analysis. Safety was assessed in all randomly assigned participants. This study is registered with ClinicalTrials.gov, number NCT02176382.

FINDINGS

Between Oct 15, 2014, and June 10, 2016, 269 women were assessed for eligibility. 76 participants were randomly assigned to 20 μg teriparatide (n=39) or 40 μg teriparatide (n=37), of whom 69 completed at least one post-baseline visit. At 15 months, mean spine aBMD had increased to a significantly greater extent in the 40 μg group (17·5% [SD 6·0] increase) than the 20 μg group (9·5% [3·2]; difference 8·1%, 95% CI 5·5 to 10·6, p<0·0001). Mean femoral neck aBMD had also increased to a greater extent in the 40 μg group (6·8% [SD 4·1] increase) than the 20 μg group (4·3% [3·7]; difference 2·5%, 0·5 to 4·5, p=0·04), as did mean total hip aBMD (40 μg group, 6·1% [3·4] increase; 20 μg group, 3·9% [2·9] increase; difference 2·2%, 0·6 to 3·8, p<0·0001). 30 (77%) of 39 participants in the 20 μg group and 29 (78%) of 37 participants in the 40 μg group had an adverse event, and seven (18%) and two (5%) patients had serious adverse events. The most frequent adverse events were joint pain (15 [38%]), muscle cramp (15 [38%]), and fatigue (12 [31%]) in the 20 μg group group and fatigue (14 [38%]), nausea (16 [43%]), and joint pain (17 [46%]) in the 40 μg group. No deaths were reported.

INTERPRETATION

Combined treatment with teriparatide 40 μg and denosumab increases spine and hip BMD more than standard combination therapy. This large and rapid increase in bone mass suggest that this high dose regimen might provide a method of restoring skeletal integrity in patients with osteoporosis.

FUNDING

National Institutes of Health and the Dart Foundation.

New Frontiers in Osteoporosis Therapy

Current osteoporosis medications reduce fractures significantly but have rare and serious adverse effects (osteonecrosis of the jaw, atypical femoral fractures) that may limit their safety for long-term use. Insights from basic bone biology and genetic disorders have led to recent advances in therapeutics for osteoporosis. New approaches now in clinical use include the antisclerostin monoclonal antibody romosozumab, as well as the parathyroid hormone-related peptide analog abaloparatide. Clinical trial data show significant antifracture benefits with recently approved romosozumab. Studies using abaloparatide build on our longstanding experience with teriparatide and the importance of consolidating the bone mineral density gains achieved from an anabolic agent by following it with an antiresorptive. Combination and sequential treatments using osteoporosis medications with different mechanisms of action have also been tested with promising results. On the horizon is the potential for cell-based therapies (e.g., mesenchymal stem cells) and drugs that target the elimination of senescent cells in the bone microenvironment.

CaMKK2 Signaling in Metabolism and Skeletal Disease: a New Axis with Therapeutic Potential

PURPOSE OF REVIEW

Age and metabolic disorders result in the accumulation of advanced glycation endproducts (AGEs), oxidative stress, and inflammation, which cumulatively cause a decline in skeletal health. Bone becomes increasingly vulnerable to fractures and its regenerative capacity diminishes under such conditions. With a rapidly aging population in the USA and the global increase in diabetes, efficacious, multi-dimensional therapies that can treat or prevent skeletal diseases associated with metabolic dysfunction and inflammatory disorders are acutely needed.

RECENT FINDINGS

Ca²⁺/calmodulin-dependent protein kinase kinase 2 (CaMKK2) is a key regulator of nutrient intake, glucose metabolism, insulin production, and adipogenesis. Recent studies suggest a pivotal role for CaMKK2 in bone metabolism, fracture healing, and inflammation. Aside from rekindling previous concepts of CaMKK2 as a potent regulator of whole-body energy homeostasis, this review emphasizes CaMKK2 as a potential therapeutic target to treat skeletal diseases that underlie metabolic conditions and inflammation.

Urinary N-Telopeptide Can Predict Pseudarthrosis After Anterior Cervical Decompression and Fusion: A Prospective Study

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

To examine preoperative urinary cross-linked n-telopeptide (uNTx) and assess for association with fusion rates in patients undergoing single and multi-level anterior cervical decompression and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

Although high rates of fusion have been reported for ACDF, the risk of pseudarthrosis remains substantial. An established marker of bone turnover, uNTx may prove useful as a predictor of fusion.

METHODS

Patients undergoing primary ACDF with allograft/plating technique from 2015 to 2017 by a single surgeon were consecutively enrolled and preoperative uNTx was collected. Patients undergoing revision, with creatinine >1.2, and with improperly-collected uNTx were excluded. Demographics, laboratory values, and fusion status were assessed at 6 months, 1 year, and 2 years postoperatively.

RESULTS

Of the 97 patients enrolled, 69 met inclusion criteria. Of included cases, 41%, 33%, 18%, and 8% underwent 1-, 2-, 3-, and 4-level ACDF, respectively. Overall, fusion rates were 37.3%, 70.9%, and 95.3% at 6 months, 1 year, and 2 years, respectively. uNTx was higher in the fusion group (31.1 vs. 22.2, P = 0.001) at 6 months and 1 year (30.0 vs. 21.0, P = 0.006), with no difference at 2 years. No differences were identified in the proportion of smokers, immunomodulatory agents, corpectomies, or fusion levels between groups. Multivariate regression analysis demonstrated that uNTx is an independent predictor of fusion (odds ratio, OR, 1.124, P = 0.003). Both groups experienced improvements in NDI and VAS neck pain at 6 months with no significant differences noted between groups. Of 16 patients with pseudarthrosis at 1 year, 2 underwent posterior cervical fusion for symptoms.

CONCLUSION

Preoperative uNTx was greater in patients with successful ACDF fusion compared with patients with pseudarthrosis at 6 months and 1 year. A negative correlation was found between preoperative uNTx and motion on dynamic imaging. These results suggest that uNTx could serve to identify patients at risk for pseudarthrosis after ACDF.

LEVEL OF EVIDENCE

3.

Molecular-Based Treatment Strategies for Osteoporosis: A Literature Review

Osteoporosis is an unavoidable public health problem in an aging or aged society. Anti-resorptive agents (calcitonin, estrogen, and selective estrogen-receptor modulators, bisphosphonates, anti-receptor activator of nuclear factor κB ligand antibody along with calcium and vitamin D supplementations) and anabolic agents (parathyroid hormone and related peptide analogs, sclerostin inhibitors) have major roles in current treatment regimens and are used alone or in combination based on the pathological condition. Recent advancements in the molecular understanding of bone metabolism and in bioengineering will open the door to future treatment paradigms for osteoporosis, including antibody agents, stem cells, and gene therapies. This review provides an overview of the molecular mechanisms, clinical evidence, and potential adverse effects of drugs that are currently used or under development for the treatment of osteoporosis to aid clinicians in deciding how to select the best treatment option.

Osteoanabolic and dual action drugs

Teriparatide (TPTD) and abaloparatide (ABL) are the only osteoanabolic drugs available, at this time, for treatment of osteoporosis. TPTD is a 34-amino acid fragment that is identical in its primary sequence to the 34 amino acids of full-length human parathyroid hormone [hPTH(1-84)]. ABL is identical to parathyroid hormone-related peptide (PTHrP) through the first 22 residues with significantly different amino acids inserted thereafter, between residues 22 and 34. The osteoanabolic actions of PTH are due directly to its effects on cells of the osteoblast lineage and indirectly by stimulating IGF-I synthesis and suppressing sclerostin and associated enhancement of Wnt signalling. Both TPTD and ABL are ligands that bind to and activate the PTH receptor type 1 (PTHR1) receptor but they appear to do so differently: ABL favours the transient, more anabolic configuration of the receptor. Both TPTD and ABL reduce the risk of vertebral fractures and non-vertebral fractures. Both drugs are administered for a maximum of 24 months, and should be followed by an antiresorptive agent to maintain gains in bone mineral density (BMD). Romosozumab, a monoclonal antibody that binds to and inhibits sclerostin, appears to have dual actions by stimulating bone formation and reducing bone resorption. In the pivotal clinical trial, romosozumab, administered as a 210 mg monthly subcutaneous dose, significantly reduced new vertebral fractures and in a subsequent study reduced both vertebral and non-vertebral fractures.

Teriparatide versus bisphosphonates for treatment of postmenopausal osteoporosis: A meta-analysis

OBJECTIVE

This meta-analysis aims to compare the efficacy of teriparatide and bisphosphonates for reducing vertebral fracture risk and bone mineral density (BMD) in lumbar spine and femoral neck in postmenopausal women with osteoporosis.

METHODS

We searched the literature, via PubMed, Embase, Cochrane Library, Web of Science and Google database to screen citations from inception to April 2018 for inclusion in this study. Only randomized controlled trials that compared teriparatide and bisphosphonates for reducing vertebral fracture risk in postmenopausal women with osteoporosis were included. Stata 12.0 was used for meta-analysis.

RESULTS

Our meta-analysis results indicated that, compared with bisphosphonates, teriparatide was associated with a reduction of the vertebral fracture risk (risk ratio (RR) = 0.57, 95% confidence interval (CI): 0.35, 0.93, P = 0.024). Furthermore, teriparatide therapy increased the mean percent change in BMD in lumbar spine of 6 months, 12 months and 18 months than bisphosphonates with statistically significant (P < 0.05). And, teriparatide has only beneficial in increasing the mean percent change in BMD in femoral neck of 18 months (P < 0.05). There was no significant difference between teriparatide and bisphosphonates in terms of the adverse events (AEs, RR = 1.09, 95% CI 0.89, 1.33, P = 0.424).

CONCLUSIONS

Teriparatide is an effective agent in reducing the risk of vertebral fracture in postmenopausal women with osteoporosis. Furthermore, teriparatide can increase the BMD in lumbar spine and femoral neck in long-terms duration.

Effects of teriparatide on hip and upper limb fractures in patients with osteoporosis: A systematic review and meta-analysis

In randomized clinical trials (RCTs) with teriparatide, the number of patients with incident hip fractures was small and insufficiently powered to show statistically significant differences between groups. We, therefore, conducted a systematic review and meta-analysis of the efficacy of teriparatide in the reduction of hip and upper limb fractures in women and men with osteoporosis. A comprehensive search of databases until 22 November 2017 was conducted for RCTs of at least 6-month duration that reported non-spine fractures (hip, humerus, forearm, wrist), either as an efficacy or safety endpoint. Only RCTs that included patients with the approved treatment indications and dose for use of teriparatide were included; trials with off-label use of teriparatide were excluded. Two independent reviewers performed study selection and data extraction. Statistical procedures included Peto's method and Mantel-Haenszel with empirical correction, as most of the RCTs reported zero events in at least one of the treatment arms. Study results are expressed as odds ratios (OR) with 95% confidence intervals (CI). Publication bias and heterogeneity were evaluated with standard statistical tests. Twenty-three RCTs were included, 19 with an active-controlled arm (representing 64.9% of the patients included in the control group) and 11 double-blind, representing data on 8644 subjects, 3893 of them treated with teriparatide. Mean age (SD) was 67.0 (4.5) years, median treatment duration 18 months (range: 6 to 24 months). A total of 34 incident hip, 31 humerus, 31 forearm, and 62 wrist fractures were included. Meta-analysis results showed an OR (95% CI) for hip fractures of 0.44 (0.22-0.87; p = 0.019) in patients treated with teriparatide compared with controls. The effects on the risk of humerus [1.02 (0.50-2.08)], forearm [0.53 (0.26-1.08)] and wrist fractures [1.21 (0.72-2.04)] were not statistically significant (p > 0.05). This meta-analysis provides evidence of efficacy of teriparatide in reducing hip fractures by 56% in patients with osteoporosis.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY CLINICAL PRACTICE GUIDELINES FOR THE DIAGNOSIS AND TREATMENT OF POSTMENOPAUSAL OSTEOPOROSIS - 2016

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists AFF = atypical femur fracture ASBMR = American Society for Bone and Mineral Research BEL = best evidence level BMD = bone mineral density BTM = bone turnover marker CBC = complete blood count CI = confidence interval DXA = dual-energy X-ray absorptiometry EL = evidence level FDA = U.S. Food and Drug Administration FLEX = Fracture Intervention Trial (FIT) Long-term Extension FRAX_® = Fracture Risk Assessment Tool GFR = glomerular filtration rate GI = gastrointestinal HORIZON = Health Outcomes and Reduced Incidence with Zoledronic Acid Once Yearly IOF = International Osteoporosis Foundation ISCD = International Society for Clinical Densitometry IU = international units IV = intravenous LSC = least significant change NBHA = National Bone Health Alliance NOF = National Osteoporosis Foundation 25(OH)D = 25-hydroxy vitamin D ONJ = osteonecrosis of the jaw PINP = serum carboxy-terminal propeptide of type I collagen PTH = parathyroid hormone R = recommendation RANK = receptor activator of nuclear factor kappa-B RANKL = receptor activator of nuclear factor kappa-B ligand RCT = randomized controlled trial RR = relative risk S-CTX = serum C-terminal telopeptide SQ = subcutaneous VFA = vertebral fracture assessment WHO = World Health Organization.

Combination therapy with parathyroid hormone analogs and antiresorptive agents for osteoporosis: a systematic review and meta-analysis of randomized controlled trials

Combination therapy with parathyroid hormone (PTH) analogs and antiresorptive agents may be more effective than monotherapy for the treatment of osteoporosis. This study aimed to estimate the effectiveness and safety of this combination therapy for osteoporosis. MEDLINE, EMBASE, and Cochrane Library were searched from inception to May 1, 2018, including randomized controlled trials (RCTs) with a duration of at least 6 months on adults with osteoporosis treated with combination therapy versus monotherapy. Outcomes included fractures, bone mineral density (BMD) changes, and adverse events. A meta-analysis was performed using a random-effect model, to estimate risk ratios (RRs) for fractures, and mean differences (MDs) for BMD changes. A total of 19 RCTs and 2177 patients were included. Compared with monotherapy, combination therapy had an advantage of 36% (RR, 0.64; 95% confidence interval (CI), 0.42-0.98) regarding fracture risk reduction. It also appears to improve lumbar spine BMD by 4.06% (95%CI = 2.60-5.53) and total hip BMD by 1.89% (95%CI = 1.25-2.53). No RCT reported an increased risk of serious adverse events. Among patients with osteoporosis, combination therapy was superior to monotherapy regarding improvement of the lumbar spine and total hip BMD, without risk of serious adverse events. Combination therapy also had an advantage over monotherapy on fracture risk reduction. However, owing to the limited sample size, additional larger studies are required to confirm this benefit.

Treatment of Osteoporosis, with a Focus on 2 Monoclonal Antibodies

Osteoporosis is a common skeletal disease characterized by bone loss and subsequent increased risk of fragility fractures. Recent advances in our mechanistic understanding of molecular communications among osteoblasts, osteoclasts, and osteocytes give insight into the important roles of the canonical Wnt/β-catenin pathway and the RANK/RANKL/OPG pathway in the process of bone remodeling. Due to the translation of the canonical Wnt/β-catenin pathway and the RANK/RANKL/OPG pathway in the regulation of osteoblasts and osteoclasts, new targets have been studied in recent years, such as sclerostin and receptor activator of NF-κB ligand (RANKL). In this review, we first introduce the signaling pathways involved in interactions among osteoblasts, osteoclasts, and osteocytes. Next, we describe clinical trials of denosumab and romosozumab, which are monoclonal antibodies that target RANKL and sclerostin, respectively. We analyze the efficacy of these drugs and provide a profile for the management of osteoporosis.

Osteoporosis in postmenopausal women in this decade: a bibliometric assessment of current research and future hotspots

Postmenopausal osteoporosis (PMOP) has already become a major public health problem. However, there was no bibliometric analysis estimating the evolutionary process of PMOP research.

PURPOSE

This study aimed to assess its scientific activity.

METHODS

Publications on PMOP were retrieved from Science Citation Index-Expanded (SCI-E) of the Web of Science (WoS) from 2008 to 2018. VOSviewer software was used for data mining and visualization. The quantity of papers, number of citations, citation frequency per year, and H-index were assessed and compared among different countries, institutes, and researchers.

RESULTS

A total of 11,142 papers were included and were cited 184,416 times. The USA contributed the most papers (3162), the most citations (83,270 times), and the highest H-index (115). Canada ranked first for the number of papers per million populations and per trillion GDP. Seven of the top ten funding agencies were industries. The key words were stratified into four clusters: cluster 1 ("basic research"), cluster 2 ("diagnosis"), cluster 3 ("treatment"), and cluster 4 ("others"). Average appearing years (AAY) of key words in cluster 1 were the largest compared to those in clusters 2 and 3. For hotspots, "miRNA" showed a relatively latest AAY of 2017.63, followed by "abaloparatide" and "adipokine".

CONCLUSION

We concluded that the USA and Europe were the most productive regions on PMOP, with a high prevalence of articles supported by pharmaceutical companies. Key word focus gradually shifted from "diagnosis" to "treatment" and then to precision medicine orientated "basic research". It is recommended to pay attention to potential research hotspots, such as "miRNA," "abaloparatide," and "adipokine".

Combined teriparatide and denosumab therapy accelerates spinal fusion following posterior lumbar interbody fusion

INTRODUCTION

Previous studies reported that teriparatide (recombinant human parathyroid hormone) accelerated spinal fusion following posterior lumbar inter-body fusion surgery, and combination therapy using teriparatide and denosumab increased bone marrow density more than teriparatide alone. The purpose of this study is to evaluate the influence of combination therapy with teriparaide and denosumab on spinal fusion after posterior lumbar interbody fusion.

MATERIALS AND METHODS

Sixteen osteoporotic patients with lumbar canal stenosis were randomly divided into two treatment groups, a teriparatide group (n=8; 20μg of teriparatide daily alone, administered from a month before surgery to 12 months after surgery) and a combination group (n=8; 20μg of teriparatide administered daily from a month before surgery to 12 months after surgery with 60mg denosumab every 6 months, administered at 2 and 8 months following surgery). All patients underwent posterior lumbar interbody fusion with local bone grafts. At 3, 6, 9, and 12 months following surgery, bone mineral density at the femoral neck was measured, and biochemical markers were obtained for bone turnover for all cases. Clinical findings were quantified using the Japanese Orthopedic Association scores before surgery, and at 6 and 12 months following surgery. Fusion rates were measured using computed tomography images before surgery, and 6 and 12 months following surgery.

RESULTS

Alkaline phosphatase in the teriparatide group increased more than in the combination group at 3 months following surgery (p<0.05). Femoral neck BMD increased more in the combination group than in the teriparatide group at 12 months following surgery. The combination group achieved higher fusion rates than the teriparatide group at 6 months following surgery.

CONCLUSIONS

Combination therapy with teriparatide and denosumab increased bone mineral density more than teriparatide alone, and accelerated spinal fusion following posterior lumbar interbody fusion.

Advances and Unmet Needs in the Therapeutics of Bone Fragility

The prevalence of fragility fractures increases as longevity increases the proportion of the elderly in the community. Until recently, the majority of studies have targeted women with osteoporosis defined as a bone mineral density (BMD) T score of < -2.5 SD, despite evidence that the population burden of fractures arises from women with osteopenia. Antiresorptive agents reduce vertebral and hip fracture risk by ~50 percent during 3 years but efficacy against non-vertebral fractures, 80% of all fractures in the community, is reported in few studies, and of those, the risk reduction is only 20-30%. Recent advances in the use of antiresorptives and anabolic agents has addressed some of these unmet needs. Zoledronic acid is now reported to reduce vertebral and non-vertebral fractures rates in women with osteopenia. Studies using teriparatide demonstrate better vertebral and clinical (symptomatic vertebral and non-vertebral) antifracture efficacy than risedronate. Abaloparatide, a peptide sharing amino acid sequences with teriparatide, reduces vertebral and non-vertebral fractures. Romosozumab, a monoclonal antibody suppressing sclerostin, reduces vertebral and non-vertebral fractures within a year of starting treatment, and does so more greatly than alendronate. Some recent studies signal undesirable effects of therapy but provide essential cautionary insights into long term management. Cessation of denosumab is associated with a rapid increase in bone remodeling and the uncommon but clinically important observation of increased multiple vertebral fractures suggesting the need to start alternative anti-resorptive therapy around the time of stopping denosumab. Antiresorptives like bisphosphonates and denosumab suppress remodeling but not completely. Antifracture efficacy may be limited, in part, as a consequence of continued unsuppressed remodeling, particularly in cortical bone. Bisphosphonates may not distribute in deeper cortical bone, so unbalanced intracortical remodeling continues to cause microstructural deterioration. In addition, suppressed remodeling may compromise the material composition by increasing matrix mineral density and glycosylation of collagen. As antiresorptive agents do not restore microstructural deterioration existing at the time of starting treatment, under some circumstances, anabolic therapy may be more appropriate first line treatment. Combining antiresorptive and anabolic therapy is an alternative but whether anti-fracture efficacy is greater than that achieved by either treatment alone is not known.

Treatment of Osteoporosis: Unmet Needs and Emerging Solutions

Efficient therapies are available for the treatment of osteoporosis, however, there are still unmet needs. Anti-resorptive therapies only increase bone mineral density to a certain extent and reduce the risk of non-vertebral fractures by 20%, only one anabolic option is available in most parts of the world-the effect of which levels off over time, and the evidence for combination therapy targeting both resorption and formation is limited. In addition, identification and treatment of patients with high and imminent fracture risk following a recent fracture and long-term adherence to treatment are 2 other very prominent challenges to the management of osteoporosis. The current review will focus on emerging osteoporosis treatments and optimized use of the existing treatments that may help overcome the currently unmet needs in the management of osteoporosis.

Osteoanabolic Agents for Osteoporosis

Medications for osteoporosis are classified as either antiresorptive or anabolic. Whereas antiresorptive agents prevent bone resorption, anabolic agents promote new bone formation. Anabolics should be considered in individuals with severe osteoporosis, failure of alternative osteoporosis agents, intolerability or contraindications to other osteoporosis agents, and glucocorticoid-induced osteoporosis. There are currently two approved anabolic therapies, teriparatide and abaloparatide, and a third anabolic agent, romozosumab, is under review by the US Food and Drug Administration. Teriparatide and abaloparatide are administered as daily subcutaneous injections and have been shown to reduce vertebral and nonvertebral fractures significantly. The most common side effects are headache and nausea, but teriparatide and abaloparatide are generally well tolerated. The sequence of administration of anabolic therapy is important. Benefits of anabolics are attenuated in individuals with prior antiresorptive exposure; however, antiresorptive agents administered after anabolics consolidate bone mineral density gains.

THERAPY OF ENDOCRINE DISEASE: Denosumab vs bisphosphonates for the treatment of postmenopausal osteoporosis

The most widely used medications for the treatment of osteoporosis are currently bisphosphonates (BPs) and denosumab (Dmab). Both are antiresorptives, thus targeting the osteoclast and inhibiting bone resorption. Dmab achieves greater suppression of bone turnover and greater increases of bone mineral density (BMD) at all skeletal sites, both in naïve and pretreated patients. No superiority on fracture risk reduction has been documented so far. In long-term administration, BPs reach a plateau in BMD response after 2-3 years, especially at the hip, while BMD increases progressively for as long as Dmab is administered. Both BPs and Dmab are generally considered safe, although they have been correlated to rare adverse events, such as osteonecrosis of the jaw and atypical femoral fractures. Dmab should be preferred in patients with impaired renal function. BPs are embedded in the bone, from which they are slowly released during bone remodeling, therefore continuing to act for years after their discontinuation. In contrast, Dmab discontinuation fully and rapidly reverses its effects on bone markers and BMD and increases the risk for fractures; therefore, Dmab discontinuation should be discouraged, especially in previously treatment-naïve patients, regardless of the conventional fracture risk. In case of discontinuation, other treatment, mainly BPs, should immediately follow, although the optimal sequential treatment strategy is yet to be defined. Combination of teriparatide with Dmab or zoledronic acid, but not alendronate, provides increased BMD gains at all sites. In conclusion, both BPs and Dmab are safe and efficient therapeutic options although their particularities should be carefully considered in an individual basis.

A Review of Osteoporosis in the Older Adult: An Update

Osteoporosis in the elderly population is common. It results in more than 1.5 million fractures per year in the United States. The goal of managing osteoporosis is to prevent fractures. In men, osteoporosis is underrecognized and undertreated. More men than women die every year as a consequence of hip fractures. Bisphosphonates are the first-line treatment of men and women. In the past several years, advances in bone biology have resulted in major therapeutic advances. A review of diagnosis and treatment of osteoporosis is described.

Efficacy and Safety of Zoledronic Acid for Treatment of Postmenopausal Osteoporosis: A Meta-Analysis of Randomized Controlled Trials

We conducted a meta-analysis based on eligible studies to assess the efficacy and safety of zoledronic acid treatment for postmenopausal women with osteoporosis. PubMed, Web of Science, and Embase were searched for eligible studies that assessed the efficacy of zoledronic acid in the prevention of fractures among postmenopausal women with osteoporosis. The primary outcomes were new vertebral fracture, nonvertebral fracture, and hip fracture. Secondary outcomes were bone mineral density (BMD) and safety outcomes. A fixed-effect or random-effect model was used to pool the estimates according to the heterogeneity among the included studies. Eight randomized controlled trials, involving 13,335 patients, were included in this meta-analysis. Pooled results showed that treatment with zoledronic acid significantly reduced the incidences of nonvertebral fractures, vertebral fractures, and hip fractures, as compared with placebo. Zoledronic acid was also associated with significant improvement in BMD at lumbar spine, total hip, femoral neck, and trochanter. However, the incidence of any adverse events was higher in the zoledronic acid group than that in the control group, and serious adverse events were comparable between the 2 groups. This meta-analysis indicated that zoledronic acid could significantly reduce the fracture risk and increase BMD in postmenopausal women with osteoporosis. Furthermore, it would not result in serious adverse events. Zoledronic acid could be used as an effective and well-tolerated treatment for postmenopausal women with osteoporosis.

Osteoporosis in chronic liver disease

Osteoporosis is a frequent complication in patients with chronic liver disease, especially in end-stages and in chronic cholestasis, in addition to non-alcoholic fatty liver disease, haemochromatosis and alcoholism. Mechanisms underlying osteoporosis are poorly understood, but osteoporosis mainly results from low bone formation. In this setting, sclerostin, a key regulator of the Wnt/β-catenin signalling pathway which regulates bone formation, in addition to the effects of the retained substances of cholestasis such as bilirubin and bile acids on osteoblastic cells, may influence the decreased bone formation in chronic cholestasis. Similarly, the damaging effects of iron and alcohol on osteoblastic cells may partially explain bone disease in haemochromatosis and alcoholism. A role for proinflammatory cytokines has been proposed in different conditions. Increased bone resorption may occur in cholestatic women with advanced disease. Low vitamin D, poor nutrition and hypogonadism, may be contributing factors to the full picture of bone disorders in chronic liver disease.

Combination therapy of anabolic agents and bisphosphonates on bone mineral density in patients with osteoporosis: a meta-analysis of randomised controlled trials

OBJECTIVE

We aimed to determine whether the concomitant combination therapy of anabolic agents and bisphosphonates produces more effects on bone mineral density (BMD) than anabolic agents alone in patients with osteoporosis.

METHODS

We searched MEDLINE, EMBASE and the Cochrane Library for publications from 1 January 1980 to 1 August 2016 to identify all the randomised controlled trials (RCTs) and quasi-RCTs. The primary outcome was the mean per cent changes in BMD at the lumbar spine, the total hip and the femoral neck with an optimal period of treatment (6 to 12 months). The secondary outcome was the mean per cent changes in BMD at the same sites with the full period of recommendation (18 to 24 months). A random-effects model was used to estimate the standardised mean differences (SMDs) and the 95% CIs.

RESULTS

Seven studies, with 747 patients, were included. With the optimal period, the concomitant combination therapy demonstrated a significant advantage over a monotherapy in BMD improvement at the total hip (SMD 0.42; 95% CI 0.26 to 0.58) and the femoral neck (SMD 0.30; 95% CI 0.14 to 0.46), but not for the spine BMD (SMD 0.13; 95% CI -0.17 to 0.43). With the full period, the concomitant combination therapy did not improve the BMD at the lumbar spine (SMD -0.06; 95% CI -0.71 to 0.59), the total hip (SMD 0.05; 95% CI -0.71 to 0.82) and the femoral neck (SMD -0.32; 95% CI -1.15 to 0.50).

CONCLUSIONS

Compared with anabolic monotherapy, the concomitant combination therapy of anabolic agents and bisphosphonates significantly improved the BMD at the total hip and femoral neck with a shorter term (6 to 12 months) and produced similar benefits on BMD for the longer term (18 to 24 months). Also, the effect of concomitant combination therapy might be affected by the dose of anabolic agents.

PROSPERO REGISTRATION NUMBER

CRD42016041335.

Osteogenesis imperfecta - A clinical update

Osteogenesis imperfecta (OI) is the most common inherited form of bone fragility and includes a heterogenous group of genetic disorders which most commonly result from defects associated with type 1 collagen. 85%-90% of cases are inherited in an autosomal dominant manner and are caused by mutations in the COL1A1 and COL1A2 genes, leading to quantitative or qualitative defects in type 1 collagen. In the last decade, defects in several other proteins involved in the normal processing of type 1 collagen have been described. Recent advances in genetics have called for reconsideration of the classification of OI, however, most recent classifications align with the classic clinical classification by Sillence. The hallmark of the disease is bone fragility but other tissues are also affected. Intravenous bisphosphonates (BPs) are the most widely used intervention, having significant favorable effects regarding areal bone mineral density (BMD) and vertebral reshaping following fractures in growing children. BPs have a modest effect in long bone fracture incidence, their effects in adults with OI concerns only BMD, while there are reports of subtrochanteric fractures resembling atypical femoral fractures. Other therapies showing promising results include denosumab, teriparatide, sclerostin inhibition, combination therapy with antiresorptive and anabolic drugs and TGF-β inhibition. Gene targeting approaches are under evaluation. More research is needed to delineate the best therapeutic approach in this heterogeneous disease.

Optimizing Sequential and Combined Anabolic and Antiresorptive Osteoporosis Therapy

As osteoporosis therapy options have expanded, and clinical guidelines have begun to embrace the concept of limited treatment courses and “drug holidays,” the choices that physicians must make when initiating, electing to continue, or switching therapies have become more complex. As a result, one of the fundamental issues that must be carefully considered is whether, when, and in what sequence anabolic therapies should be utilized. This review evaluates the current evidence supporting the optimal sequence for the use of anabolic and antiresorptive drugs and assesses the expanding number of clinical trials favoring the initial use of anabolic therapy followed by an antiresorptive agent. This review also explores the evidence suggesting that the effectiveness of anabolic medications are diminished when used in patients that have been previously treated with specific antiresorptive drugs for prolonged periods. Finally, the recent advances in designing combination antiresorptive/anabolic treatment approaches are detailed, with a focus on combined denosumab/teriparatide regimens, which appear to provide the most substantial and clinically relevant skeletal benefits to patients with established osteoporosis. © 2018 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

MANAGEMENT OF ENDOCRINE DISEASE: Novel anabolic treatments for osteoporosis

Skeletal anabolic agents enhance bone formation, which is determined by the number and function of osteoblasts. Signals that influence the differentiation and function of cells of the osteoblast lineage play a role in the mechanism of action of anabolic agents in the skeleton. Wnts induce the differentiation of mesenchymal stem cells toward osteoblasts, and insulin-like growth factor I (IGF-I) enhances the function of mature osteoblasts. The activity of Wnt and IGF-I is controlled by proteins that bind to the growth factor or to its receptors. Sclerostin is a Wnt antagonist that binds to Wnt co-receptors and prevents Wnt signal activation. Teriparatide, a 1-34 amino terminal fragment of parathyroid hormone (PTH), and abaloparatide, a modified 1-34 amino terminal fragment of PTH-related peptide (PTHrp), induce IGF-I, increase bone mineral density (BMD), reduce the incidence of vertebral and non-vertebral fractures and are approved for the treatment of postmenopausal osteoporosis. Romosozumab, a humanized anti-sclerostin antibody, increases bone formation, decreases bone resorption, increases BMD and reduces the incidence of vertebral fractures. An increased incidence of cardiovascular events has been associated with romosozumab, which is yet to be approved for the treatment of osteoporosis. In conclusion, cell and molecular studies have formed the foundation for the development of new anabolic therapies for osteoporosis with proven efficacy on the incidence of new fractures.

Effects of teriparatide and risedronate on new fractures in post-menopausal women with severe osteoporosis (VERO): a multicentre, double-blind, double-dummy, randomised controlled trial

BACKGROUND

No clinical trials have compared osteoporosis drugs with incident fractures as the primary outcome. We compared the anti-fracture efficacy of teriparatide with risedronate in patients with severe osteoporosis.

METHODS

In this double-blind, double-dummy trial, we enrolled post-menopausal women with at least two moderate or one severe vertebral fracture and a bone mineral density T score of less than or equal to -1·50. Participants were randomly assigned to receive 20 μg of teriparatide once daily plus oral weekly placebo or 35 mg of oral risedronate once weekly plus daily injections of placebo for 24 months. The primary outcome was new radiographic vertebral fractures. Secondary, gated outcomes included new and worsened radiographic vertebral fractures, clinical fractures (a composite of non-vertebral and symptomatic vertebral), and non-vertebral fractures. This study is registered with ClinicalTrials.gov (NCT01709110) and EudraCT (2012-000123-41).

FINDINGS

We enrolled 680 patients in each group. At 24 months, new vertebral fractures occurred in 28 (5·4%) of 680 patients in the teriparatide group and 64 (12·0%) of 680 patients in the risedronate group (risk ratio 0·44, 95% CI 0·29-0·68; p<0·0001). Clinical fractures occurred in 30 (4·8%) of 680 patients in the teriparatide group compared with 61 (9·8%) of 680 in the risedronate group (hazard ratio 0·48, 95% CI 0·32-0·74; p=0·0009). Non-vertebral fragility fractures occurred in 25 (4·0%) patients in the teriparatide group and 38 (6·1%) in the risedronate group (hazard ratio 0·66; 95% CI 0·39-1·10; p=0·10).

INTERPRETATION

Among post-menopausal women with severe osteoporosis, the risk of new vertebral and clinical fractures is significantly lower in patients receiving teriparatide than in those receiving risedronate.

FUNDING

Lilly.

The effect of once-yearly zoledronic acid on hip structural and biomechanical properties derived using computed tomography (CT) in Japanese women with osteoporosis

The effects of zoledronic acid on hip structural and biomechanical properties were evaluated in Japanese patients with osteoporosis by computed tomography (CT). The subjects included in this study were a subset of female subjects (zoledronic acid group, 49 subjects; placebo group, 53 subjects) in the phase 3 trial (ZONE study) who were available for multi-detector row CT (MDCT) scanning. Eligible subjects were those diagnosed with primary osteoporosis based on the Diagnostic Criteria for Primary Osteoporosis (2000) by the Japanese Society for Bone and Mineral Research and who had between one and four fractured vertebrae located between the fourth thoracic vertebra and the fourth lumbar vertebra. The subjects received a once-yearly intravenous infusion of zoledronic acid 5mg or placebo for two years. CT data were obtained at baseline and at 12 and 24months later and analyzed under blinded conditions. The results demonstrated that once-yearly intravenous infusion of zoledronic acid improved volumetric bone mineral density (vBMD), cortical bone geometry parameters, and CT-derived biomechanical parameters at the femoral neck, intertrochanteric region, and shaft; particularly at the intertrochanteric region, significant improvements in cortical bone geometry parameters and CT-derived biomechanical parameters, compared with those in the placebo group, were detectable early, at 12months. The present data suggest that zoledronic acid has a possibility to reduce the risk of hip fractures in Japanese patients with osteoporosis.