Anti-sclerostin antibody therapy prevents post-ischemic osteonecrosis bone collapse via interleukin-6 association

Osteonecrosis of the femoral head (ONFH) is a debilitating condition characterized by subchondral bone necrosis, which frequently culminates in joint destruction. Although total hip arthroplasty is conventionally practiced to remediate ONFH, for patients under the age of 60, the outcomes can be suboptimal. Chronic inflammation, particularly that mediated by interleukin-6 (IL-6), has been conjectured to be a potential mechanism underlying the etiology of ONFH. This study aimed at exploring the interplay between IL-6, the canonical Wnt signaling pathway, and ONFH to provide insights for potential therapeutic interventions. Human ONFH specimens depicted an elevation in β-catenin expression in the transitional layer, while IL-6 levels were pronounced in the same region. Subsequently, mouse models of ischemic osteonecrosis were treated with an anti-sclerostin antibody to assess its effects on bone metabolism and cellular processes. Histological analysis revealed that the administration of anti-sclerostin antibodies effectuated early recovery from bone necrosis, reduced empty lacunae, and suppressed IL-6 expression. The treatment evidently initiated the activation of the Wnt/β-catenin signaling pathway, presenting a potential mechanism associated with IL-6-mediated inflammation. Furthermore, the antibody upregulated osteoblast formation, downregulated osteoclast formation, and increased bone volume. Micro-CT imaging demonstrated increased bone volume, prevented epiphyseal deformity, and improved compression strength. Therefore, this study yields significant findings, indicating the potency of anti-sclerostin antibodies in effectively modulating the Wnt/β-catenin pathway, associating with IL-6 expression, and preventing post-ONFH bone collapse. Additionally, this preclinical investigation in mouse models offers an avenue for prospective research on potential therapeutic interventions against human ONFH.

Effect of romosozumab in premenopausal women with severe osteoporosis and anorexia nervosa

Objectives

This study aims to investigate the effects of romosozumab on bone mineral density (BMD) and bone metabolism.

Methods

In this retrospective case series, romosozumab was administered to 5 premenopausal female patients with osteoporosis and anorexia nervosa with fragility fractures. BMD and bone turnover marker changes were investigated at 6 months and 1 year after administering romosozumab.

Results

BMD increased and high-turnover bone metabolism decreased 6 months and 1 year after administering romosozumab.

Conclusions

Romosozumab is useful for treating osteoporosis in patients with anorexia nervosa.

Therapeutic Use of Anti-Sclerostin Antibody in the Treatment of Multiple Myeloma: A Systematic Review

Multiple myeloma is a malignant cancerous condition that is characterized by abnormal plasma cell production and can lead to bone destruction due to increased osteoclastic activity and decreased osteoblastic activity. Many therapeutic therapies are used to treat diseases, such as chemotherapy and radiotherapy. In recent years, anti-sclerostin antibody treatment has been under investigation for its effect on the multiple myeloma. The present study was conducted to assess the effective therapeutic use of anti-sclerostin antibody in the treatment of multiple myeloma. The literature search was conducted using PubMed, Google Scholar, ScienceDirect, and PubMed Central using the following MeSH terms: "multiple myeloma", "anti-sclerostin antibody", "ubiquitin-proteasome pathway", "proteasome inhibitor", "Wnt pathway". A total of 348 articles were screened. Twenty-five out of 348 were full-text articles assessed for eligibility, and four articles were used in this systematic review. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for the reporting of this systematic review. A total of four randomized control trials (RCT) were included and used in this systematic review. The anti-sclerostin antibodies were various other drugs, and it was found that the anti-sclerostin antibody was effective in preventing autoantibody formation, decreasing bone destruction, and increasing trabecular bone. Anti-sclerostin antibody was found to be effective in decreasing bone destruction by reducing osteoclastic activity and increasing osteoblastic activity associated with multiple myeloma.

[A breakthrough in the management of postmenopausal osteoporosis with very high fracture risk : romosozumab (Evenity®), a humanized monoclonal anti-sclerostin antibody]

Romosozumab (Evenity®) is a humanized monoclonal anti-sclerostin antibody. It represents a major breakthrough in the treatment of osteoporosis: while most treatments inhibit bone resorption, romosozumab has a dual effect, by increasing bone formation and reducing bone resorption. It is reimbursed in postmenopausal osteoporosis in patients with very high fracture risk (i.e. after a recent major fracture, occurring within two years). Its ideal use, in the therapeutic sequence for post-menopausal women, is as first line treatment in case of a recent major fracture. It is contraindicated in case of hypocalcemia and personal history of stroke or myocardial infarction.

Effect of the duration of previous osteoporosis treatment on the effect of romosozumab treatment

The effect of romosozumab is affected by previous osteoporosis treatment. Here we showed that the duration of the previous treatment just before romosozumab affects the therapeutic effect of romosozumab. Using denosumab and oral bisphosphonates for more than 1 year attenuates the effect of romosozumab.

INTRODUCTION

As an anti-sclerostin antibody, romosozumab suppresses bone resorption and stimulates bone formation. We investigated whether the effectiveness of 12 months of romosozumab treatment depended on the duration of previous treatment with teriparatide, denosumab, or oral bisphosphonates.

METHODS

In total, 259 osteoporosis patients received subcutaneous injections of romosozumab (210 mg) every 4 weeks during 2019 and 2020. This study was designed as a pre-post comparison. The end points were the percent changes of bone mineral density (BMD) after 12 months of romosozumab treatment. The patients were divided into seven groups depending on the type and duration of previous treatment before starting romosozumab as follows: non-previous treatment group, change from teriparatide used for 1 year or less/more than 1 year, change from denosumab used for 1 year or less/more than 1 year, and change from oral bisphosphonates used for 1 year or less/more than 1 year.

RESULTS

The effects of previous treatment with teriparatide on the effectiveness of 12-month romosozumab did not clearly depend on the duration of treatment (p > 0.05). In contrast, the effects of previous treatments with denosumab or oral bisphosphonates on the effectiveness of 12-month romosozumab depended on the previous treatment duration, which was reflected by the differences in percent change of the spine BMD (both p < 0.05), however, there were no significant differences in the percent change of the total hip BMD (both p > 0.05).

CONCLUSION

The duration of the previous treatment affected the effectiveness of romosozumab. Using denosumab and oral bisphosphonate for more than 1 year attenuated the effect of romosozumab.

Early clinical effects, safety, and predictors of the effects of romosozumab treatment in osteoporosis patients: one-year study

Romosozumab is an effective treatment for spine osteoporosis because it reduces the incidence of new fractures and significantly increases the percent change in the spine BMD at 12 months. The percent change in the spine BMD is higher in patients not previously treated with other anti-osteoporosis medications.

INTRODUCTION

Romosozumab appeared as a new osteoporosis medication in Japan in 2019. It is an anti-sclerostin antibody, which increases bone formation and suppresses bone resorption. The aim of our study was to elucidate the clinical effects, safety, and predictors of the effects of one-year romosozumab treatment.

METHODS

This study was an observational study designed as a pre-post study in 262 patients. Romosozumab (210 mg) was administered subcutaneously once every 4 weeks during 12 months. We focused on incidence of new fractures, safety, bone mineral density (BMD) at the spine and total hip, and bone metabolism markers.

RESULTS

There were five cases of new fractures during one-year romosozumab treatment. There were no fatal adverse events. Percent changes from baseline in the spine and total hip BMD after 12 months of romosozumab treatment were 10.67% and 2.04%, respectively. Romosozumab had better effects in cases of severe osteoporosis with low spine BMD, high TRACP-5b, and high iP1NP at the start of romosozumab treatment. The percent change in the spine BMD at 12 months was significantly lower in the group transitioning from bisphosphonates than in the group not previously treated with other anti-osteoporosis medications.

CONCLUSION

Romosozumab is an effective treatment for spine osteoporosis because it significantly increases the percent change in the spine BMD at 12 months. The percent change in the spine BMD is higher in patients not previously treated with other anti-osteoporosis medications.

Early clinical effects, safety, and appropriate selection of bone markers in romosozumab treatment for osteoporosis patients: a 6-month study

Our 6-month study showed the usefulness of romosozumab for preventing fractures and its safety. It was effective in patients with low baseline spine BMD, high TRACP-5b, and high iP1NP. Percent change from baseline of TRACP-5b and iP1NP after 1 month correlated with that from baseline of BMD after four to 6-month treatment.

INTRODUCTION

Romosozumab appeared as a new osteoporosis medication in Japan in 2019. It is an anti-sclerostin antibody which increases bone formation and suppresses bone resorption. In this study, we analyzed the actual clinical effects, adverse effects, and the optimal way to evaluate the treatment.

METHODS

Romosozumab was administered as subcutaneous injection of 210 mg once every 4 weeks. We conducted pre-post study in 185 patients treated for 6 months. We focused on the incidence of new vertebral fractures, safety, bone mineral density (BMD) at the spine and total hip, and bone metabolism markers. We evaluated BMD before romosozumab treatment and after 4 to 6 months and performed the serum analysis before romosozumab treatment, after 1, 3, and 6 months.

RESULTS

There was no new fracture during treatment, and there was no fatal adverse event including cardiovascular disease. Since percent changes from baseline of the spine and total hip BMD were 6.34% and 1.53% after 4- to 6-month treatment, the treatment was effective for spine osteoporosis. Tartrate-resistant acid phosphatase 5b (TRACP-5b) and intact type I procollagen N-terminal propeptide (iP1NP) had significant changes during romosozumab treatment (p < 0.05). Percent change from baseline of TRACP-5b and iP1NP after 1 month correlated with percent change from baseline of BMD after 4 to 6 months of treatment.

CONCLUSION

Romosozumab is effective in preventing fractures and useful for increasing the spine BMD. Also, romosozumab is relatively safe to use. It is especially effective in patients with low baseline spine BMD, high TRACP-5b, and high iP1NP.

Anabolic Therapy for the Treatment of Osteoporosis in Childhood

PURPOSE OF REVIEW

Numerous forms of osteoporosis in childhood are characterized by low bone turnover (for example, osteoporosis due to neuromuscular disorders and glucocorticoid exposure). Anti-resorptive therapy, traditionally used to treat osteoporosis in the young, is associated with further reductions in bone turnover, raising concerns about the long-term safety and efficacy of such therapy. These observations have led to increasing interest in the role of anabolic therapy to treat pediatric osteoporosis.

RECENT FINDINGS

While growth hormone and androgens appears to be relatively weak anabolic modulators of bone mass, emerging therapies targeting bone formation pathways (anti-transforming growth factor beta antibody and anti-sclerostin antibody) hold considerable promise. Teriparatide remains an attractive option that merits formal study for patients post-epiphyseal fusion, although it must be considered that adult studies have shown its effect is blunted when administered following bisphosphonate therapy. Mechanical stimulation of bone through whole body vibration therapy appears to be much less effective than bisphosphonate therapy for treating osteoporosis in children. New anabolic therapies which target important pathways in skeletal metabolism merit further study in children, including their effects on fracture risk reduction and after treatment discontinuation.

Compromised vertebral structural and mechanical properties associated with progressive kidney disease and the effects of traditional pharmacological interventions

BACKGROUND/AIMS

Patients with chronic kidney disease mineral and bone disorder (CKD-MBD) have a significantly higher vertebral and non-vertebral fracture risk than the general population. Several preclinical models have documented altered skeletal properties in long bones, but few data exist for vertebral bone. The goal of this study was to examine the effects of progressive CKD on vertebral bone structure and mechanics and to determine the effects of treatment with either bisphosphonates or anti-sclerostin antibody in groups of animals with high or low PTH.

METHODS

Animals with progressive kidney disease were left untreated, treated with calcium to lower PTH, zoledronic acid to lower remodeling without affecting PTH, anti-sclerostin antibody, or anti-sclerostin antibody plus calcium. Non-diseased, untreated littermates served as controls. Vertebral bone morphology (trabecular and cortical) and mechanical properties (structural and material-level) were assessed at 35 weeks of age by microCT and mechanical testing, respectively.

RESULTS

CKD with high PTH resulted in 6-fold higher bone formation rate, significant reductions in the amount of trabecular and cortical bone, and compromised whole bone mechanical properties in the vertebra compared to normal animals. Treatments that reduced bone remodeling were effective in normalizing vertebral structure and mechanical properties only if the treatment reduced serum PTH. Similarly, treatment with anti-sclerostin antibody was effective in enhancing bone mass and mechanical properties but only if combined with PTH-suppressive treatment.

CONCLUSIONS

CKD significantly altered both cortical and trabecular bone properties in the vertebra resulting in compromised mechanical properties and these changes can be normalized by interventions that involve reductions in PTH levels.

Effects of anti-sclerostin antibody and running on bone remodeling and strength

Sclerostin antibody (Scl-Ab) represents a promising therapeutic approach to treat patients with osteoporosis.

PURPOSE

The aim of this study was to investigate the effects of Scl-Ab, running and a combination of both on bone formation.

METHODS

Sixty female Wistar rats, aged 8 months were randomly assigned to five groups (subcutaneous injections performed twice a week): (1) (Sham): sedentary rats + saline, (2) (OVX): ovariectomized rats + saline, (3) (OVX + E): OVX rats + saline + treadmill training (5 times/week, 1 h/day), (4) (OVX + E + S): OVX rats + treadmill training + 5 mg/kg Scl-Ab and (5) (OVX + S): OVX rats + 5 mg/kg Scl-Ab. After 14 weeks, body composition, whole body and femoral BMDs were determined by DXA and serum was collected for analysis of osteocalcin and NTX. Bone microarchitecture was analyzed using μCT and bone strength was assessed at the femur mid-shaft in 3-point bending.

RESULTS

Running exercise decreased fat mass as well as the bone resorption marker NTX relative to the non-exercised control groups, effects that were associated with a prevention of the deleterious effects of OVX on whole body and femoral BMDs. Scl-Ab increased the bone formation marker osteocalcin, which resulted in robust increases in BMD and femoral metaphyseal bone volume to levels greater than in the Sham group. OVX + S + E group did not further impact on bone mass relative to the OVX + S group. At the cortical femur diaphysis, Scl-Ab prevented the decreases in bone strength after OVX, while exercise did not affect cortical strength.

CONCLUSION

We suggest that while running on a treadmill can prevent some bone loss through a modest antiresorptive effect, it did not contribute to the robust bone-forming effects of Scl-Ab when combined in an estrogen ablation model.

Treatment of post-menopausal osteoporosis: beyond bisphosphonates

Osteoporosis is a highly prevalent condition, characterized by compromised bone strength and fragility fractures and with an important associated socio-economic burden. Bisphosphonates are well established as the first line treatment for osteoporosis. However, while randomized control trials have in general demonstrated reasonable anti-fracture efficacy at the spine, they have shown moderate reduction in fracture incidence for non-vertebral sites. Furthermore, oral bisphosphonates are commonly associated with adverse gastrointestinal effects and both oral and parenteral bisphosphonates have been linked with osteonecrosis of the jaw and atypical femoral fracture, two rare but debilitating side effects. In addition, bisphosphonates are not recommended in patients with GFR <35 ml/min/1.73 m(2). Hence, there is a clear requirement for newer agents, which are able to reduce fracture risk further, whilst overcoming the limitations of bisphosphonates. Over the past 20 years, knowledge and a deeper understanding of the various signalling pathways involved in bone remodelling has increased, enabling identification of additional targets for therapy. This review focuses on these newer therapies and includes anti-resorptive agents such as raloxifene and other selective oestrogen receptor modulators, the monoclonal antibody denosumab (which inhibits the RANKL pathway), odanacatib, a cathepsin K inhibitor and the anabolic agents, PTH analogue; PTH (1-34) and anti-sclerostin antibodies (activator of the Wnt pathway). Strontium ranelate will not be reviewed as recent reports highlight concerns surrounding its cardiovascular safety and together with an apparent increased risk of thrombosis, its future use remains uncertain. Some of these agents such as raloxifene, denosumab and teriparatide are already in clinical use whilst others are at varying stages of development. This review will provide an overview of the mechanisms of action of these therapeutic agents on the skeleton and assess their efficacy in osteoporosis and fracture prevention.

Anti-sclerostin antibodies: utility in treatment of osteoporosis

Monoclonal antibodies to molecular targets important for bone formation and bone resorption are being investigated for treatment of postmenopausal osteoporosis. Postmenopausal osteoporosis is characterized by increased bone turnover, with bone resorption typically exceeding bone formation. These pathophysiological changes cause decreased bone mineral density and disruption of bone microarchitecture which lead to low-trauma fractures. Sclerostin is a glycoprotein inhibitor of osteoblast Wnt signaling produced by osteocytes that has been recognized as a new target for therapeutic intervention in patients with osteoporosis. Sclerostin was first recognized when disorders with inactivating mutations of the sclerostin gene SOST were found to be associated with high bone mass. These observations suggested that inhibitors of sclerostin might be used to increase bone mineral density. Romosozumab (AMG 785) is the first humanized anti-sclerostin monoclonal antibody that has been demonstrated to increase bone formation. This investigational monoclonal antibody, and blosozumab, another investigational anti-sclerostin antibody, have osteoanabolic properties with the potential to improve clinical outcomes in patients with osteoporosis. Similar to preclinical animal studies with sclerostin antibodies, initial clinical studies have shown that romosozumab increases bone formation and BMD. Further evaluation of the efficacy and safety of this agent in a large phase III controlled study is awaited. Phase I clinical trial data have recently been published with blosozumab. These novel interventions appear to be promising agents for the treatment of osteoporosis.