Long-term treatment with bisphosphonates and their safety in postmenopausal osteoporosis

Bisphosphonates Related Ocular Side Effects: A Case Series and Review of Literature

OBJECTIVE

To describe the clinical features of patients with bisphosphonate related ocular side effects (BROSE).

METHODS

The medical records of all patients with BROSE between January 2009 and December 2019 were reviewed.

RESULTS

Nine cases with BROSE were identified. All subjects were female. Median age at diagnosis was of 69 years. The leading indication for bisphosphonate treatment was osteoporosis (n=7), Paget's disease of bone (n=1) and breast cancer (n=1). Six (66.67%) patients presented with uveitis, one (11%) episcleritis and two (22%) with orbital inflammation. Five events (55.5%) occurred within 10 days of initiating the bisphosphonate and the rest (44.44%) developed within 2 weeks to 3 years later. Four (44.44%) patients had concurrent thyroid disease. An association was found between underlying thyroid disease or autoimmunity.

CONCLUSION

BROSE is an uncommon complication of bisphosphonate therapy occurring more frequently in patients with an autoimmune predisposition.

Development of Bisphosphonate-Conjugated Antibiotics to Overcome Pharmacodynamic Limitations of Local Therapy: Initial Results with Carbamate Linked Sitafloxacin and Tedizolid

The use of local antibiotics to treat bone infections has been questioned due to a lack of clinical efficacy and emerging information about Staphylococcus aureus colonization of the osteocyte-lacuno canalicular network (OLCN). Here we propose bisphosphonate-conjugated antibiotics (BCA) using a “target and release” approach to deliver antibiotics to bone infection sites. A fluorescent bisphosphonate probe was used to demonstrate bone surface labeling adjacent to bacteria in a S. aureus infected mouse tibiae model. Bisphosphonate and hydroxybisphosphonate conjugates of sitafloxacin and tedizolid (BCA) were synthesized using hydroxyphenyl and aminophenyl carbamate linkers, respectively. The conjugates were adequately stable in serum. Their cytolytic activity versus parent drug on MSSA and MRSA static biofilms grown on hydroxyapatite discs was established by scanning electron microscopy. Sitafloxacin O-phenyl carbamate BCA was effective in eradicating static biofilm: no colony formation units (CFU) were recovered following treatment with 800 mg/L of either the bisphosphonate or α-hydroxybisphosphonate conjugated drug (p < 0.001). In contrast, the less labile tedizolid N-phenyl carbamate linked BCA had limited efficacy against MSSA, and MRSA. CFU were recovered from all tedizolid BCA treatments. These results demonstrate the feasibility of BCA eradication of S. aureus biofilm on OLCN bone surfaces and support in vivo drug development of a sitafloxacin BCA.

Targeting Histone Modifications in Bone and Lung Metastatic Cancers

PURPOSE OF REVIEW

Breast cancer frequently metastasizes to the bone and lung, but the ability to treat metastatic tumor cells remains a pressing clinical challenge. Histone deacetylases (HDACs) and histone acetyltransferases (HATs) have emerged as promising targets since these enzymes are aberrantly expressed in numerous cancers and regulate the expression of genes that drive tumorigenesis and metastasis. This review focuses on the abnormal expression of histone-modifying enzymes in cancers that have a high tropism for the bone and lung and explores the clinical use of histone deacetylase inhibitors for the treatment and prevention of metastasis to these sites.

RECENT FINDINGS

Preclinical studies have demonstrated that the role for HDACs is highly dependent on tumor type and stage of disease progression. HDAC inhibitors can induce apoptosis, senescence, cell differentiation, and tumor dormancy genes and inhibit angiogenesis, making these promising therapeutics for the treatment of metastatic disease. HDAC inhibitors are already FDA approved for hematologic malignancies and are in clinical trials with standard-of-care chemotherapies and targeted agents for several solid tumors, including cases of metastatic disease. However, these drugs can negatively impact bone homeostasis. Although HDAC inhibitors are not currently administered for the treatment of bone and lung metastatic disease, preclinical studies have shown that these drugs can reduce distant metastasis by targeting molecular factors and signaling pathways that drive tumor cell dissemination to these sites. Thus, HDAC inhibitors in combination with bone protective therapies may be beneficial in the treatment of bone metastatic cancers.

Bone Morphogenetic Protein-2 in Development and Bone Homeostasis

Bone morphogenetic proteins (BMPs) are multi-functional growth factors belonging to the Transforming Growth Factor-Beta (TGF-β) superfamily. These proteins are essential to many developmental processes, including cardiogenesis, neurogenesis, and osteogenesis. Specifically, within the BMP family, Bone Morphogenetic Protein-2 (BMP-2) was the first BMP to be characterized and has been well-studied. BMP-2 has important roles during embryonic development, as well as bone remodeling and homeostasis in adulthood. Some of its specific functions include digit formation and activating osteogenic genes, such as Runt-Related Transcription Factor 2 (RUNX2). Because of its diverse functions and osteogenic potential, the Food and Drug Administration (FDA) approved usage of recombinant human BMP-2 (rhBMP-2) during spinal fusion surgery, tibial shaft repair, and maxillary sinus reconstructive surgery. However, shortly after initial injections of rhBMP-2, several adverse complications were reported, and alternative therapeutics have been developed to limit these side-effects. As the clinical application of BMP-2 is largely implicated in bone, we focus primarily on its role in bone. However, we also describe briefly the role of BMP-2 in development. We then focus on the structure of BMP-2, its activation and regulation signaling pathways, BMP-2 clinical applications, and limitations of using BMP-2 as a therapeutic. Further, this review explores other potential treatments that may be useful in treating bone disorders.

Challenges and strategies in management of osteoporosis and fragility fracture care during COVID-19 pandemic

Background

COVID-19 has resulted in restriction of face to face consultations and mechanisms to access health care. Osteoporosis and fragility fractures forms a significant proportion of adult trauma and orthopaedic workload even during the pandemic.

Aims

We assess the challenges and strategies used in the management of osteoporosis and fragility fracture care during the COVID-19 pandemic.

Methods

We have done a comprehensive review of the literature using suitable keywords on the search engines of PubMed, SCOPUS, Google Scholar and Research Gate in the first week of May 2020 on developments and guidance during the current COVID-19 pandemic.

Results

Osteoporosis and fragility fractures management has been hampered by lock down and infection transmission strategies used to contain the COVID-19 pandemic. Access to diagnostic tests, treatment facilities with the need to use clinical and prediction tools to guide management Telemedicine has an evolving role.

Conclusion

Osteoporosis and fragility fractures in elderly individuals pose a real challenge for an appropriate diagnosis and management, during the COVID-19 pandemic. A clinical decision along with use of clinical prediction tools for osteoporosis should be used to direct treatment. Obligatory fractures such as hip fractures require operative intervention. Non-obligatory fractures such as distal radius fractures can be managed conservatively with use of telemedicine applications in monitoring both types of patients.

Bisphosphonate use in the horse: what is good and what is not?

Background

Bisphosphonates (BPs) are a family of molecules characterized by two key properties: their ability to bind strongly to bone mineral and their inhibitory effects on mature osteoclasts and thus bone resorption. Chemically two groups of BPs are recognized, non-nitrogen-containing and nitrogen-containing BPs. Non-nitrogen-containing BPs incorporate into the energy pathways of the osteoclast, resulting in disrupted cellular energy metabolism leading to cytotoxic effects and osteoclast apoptosis. Nitrogen-containing BPs primarily inhibit cholesterol biosynthesis resulting in the disruption of intracellular signaling, and other cellular processes in the osteoclast.

Body

BPs also exert a wide range of physiologic activities beyond merely the inhibition of bone resorption. Indeed, the breadth of reported activities include inhibition of cancer cell metastases, proliferation and apoptosis in vitro. In addition, the inhibition of angiogenesis, matrix metalloproteinase activity, altered cytokine and growth factor expression, and reductions in pain have been reported. In humans, clinical BP use has transformed the treatment of both post-menopausal osteoporosis and metastatic breast and prostate cancer. However, BP use has also resulted in significant adverse events including acute-phase reactions, esophagitis, gastritis, and an association with very infrequent atypical femoral fractures (AFF) and osteonecrosis of the jaw (ONJ).

Conclusion

Despite the well-characterized health benefits of BP use in humans, little is known regarding the effects of BPs in the horse. In the equine setting, only non-nitrogen-containing BPs are FDA-approved primarily for the treatment of navicular syndrome. The focus here is to discuss the current understanding of the strengths and weaknesses of BPs in equine veterinary medicine and highlight the future utility of these potentially highly beneficial drugs.

Bone mineral density and risk of type 2 diabetes and coronary heart disease: A Mendelian randomization study

Background: Observational studies have demonstrated that increased bone mineral density is associated with a higher risk of type 2 diabetes (T2D), but the relationship with risk of coronary heart disease (CHD) is less clear. Moreover, substantial uncertainty remains about the causal relevance of increased bone mineral density for T2D and CHD, which can be assessed by Mendelian randomisation studies.  Methods: We identified 235 independent single nucleotide polymorphisms (SNPs) associated at p<5×10 ^-8 with estimated heel bone mineral density (eBMD) in 116,501 individuals from the UK Biobank study, accounting for 13.9% of eBMD variance. For each eBMD-associated SNP, we extracted effect estimates from the largest available GWAS studies for T2D (DIAGRAM: n=26,676 T2D cases and 132,532 controls) and CHD (CARDIoGRAMplusC4D: n=60,801 CHD cases and 123,504 controls). A two-sample design using several Mendelian randomization approaches was used to investigate the causal relevance of eBMD for risk of T2D and CHD. In addition, we explored the relationship of eBMD, instrumented by the 235 SNPs, on 12 cardiovascular and metabolic risk factors. Finally, we conducted Mendelian randomization analysis in the reverse direction to investigate reverse causality. Results: Each one standard deviation increase in genetically instrumented eBMD (equivalent to 0.14 g/cm ²) was associated with an 8% higher risk of T2D (odds ratio [OR] 1.08; 95% confidence interval [CI]: 1.02 to 1.14; p=0.012) and 5% higher risk of CHD (OR 1.05; 95%CI: 1.00 to 1.10; p=0.034). Consistent results were obtained in sensitivity analyses using several different Mendelian randomization approaches. Equivalent increases in eBMD were also associated with lower plasma levels of HDL-cholesterol and increased insulin resistance. Mendelian randomization in the reverse direction using 94 T2D SNPs or 52 CHD SNPs showed no evidence of reverse causality with eBMD. Conclusions: These findings suggest a causal relationship between elevated bone mineral density with risks of both T2D and CHD.

The effect of vitamin D and bisphosphonate on fracture healing: An experimental study

BACKGROUND

The aim of the study was to evaluate the effects of the using bisphosphonate, vitamin D, and a combination of bisphosphonate and vitamin D on fracture healing, by comparison of radiological and histological findings of the study groups and a control group.

METHODS

A total of 24 rats were randomly divided into 4 groups. A mid-third fracture was created in the femur of all rats. Saline was administered to Group A, bisphosphonate (Alendronate) to Group B, bisphosphonate (Alendronate) + vitamin D (Calcitriol) to Group C and vitamin D (Calcitriol) to Group D. All preparations were administered orally for 28 days.

RESULTS

No statistically significant difference was determined between the groups in respect of the effect on fracture healing according to radiological findings. The histological findings of fracture healing showed Groups B and C to be significantly more advanced than Group A (p = 0.017, p = 0.009). However no significant difference was found in Group D comparison with Group A (p = 0.224).

CONCLUSION

According to the histological findings, advanced fracture healing was seen in the groups administered with bisphosphonate or combined bisphosphonate and vitamin D compared to the use of vitamin D alone and the control group. It was concluded that bisphosphonate treatment combined with vitamin D can be used safely without any negative effect on fracture healing.

Risk of atrial fibrillation among bisphosphonate users: a multicenter, population-based, Italian study

Bisphosphonate treatment is used to prevent bone fractures. A controversial association of bisphosphonate use and risk of atrial fibrillation has been reported. In our study, current alendronate users were associated with a higher risk of atrial fibrillation as compared with those who had stopped bisphosphonate (BP) therapy for more than 1 year.

INTRODUCTION

Bisphosphonates are widely used to prevent bone fractures. Controversial findings regarding the association between bisphosphonate use and the risk of atrial fibrillation (AF) have been reported. The aim of this study was to evaluate the risk of AF in association with BP exposure.

METHODS

We performed a nested case-control study using the databases of drug-dispensing and hospital discharge diagnoses from five Italian regions. The data cover a period ranging from July 1, 2003 to December 31, 2006. The study population comprised new users of bisphosphonates aged 55 years and older. Patients were followed from the first BP prescription until an occurrence of an AF diagnosis (index date, i.e., ID), cancer, death, or the end of the study period, whichever came first. For the risk estimation, any AF case was matched by age and sex to up to 10 controls from the same source population. A conditional logistic regression was performed to obtain the odds ratio with 95% confidence intervals (CI). The BP exposure was classified into current (<90 days prior to ID), recent (91-180), past (181-364), and distant past (≥365) use, with the latter category being used as a reference point. A subgroup analysis by individual BP was then carried out.

RESULTS

In comparison with distant past users of BP, current users of BP showed an almost twofold increased risk of AF: odds ratio (OR) = 1.78 and 95% CI = 1.46-2.16. Specifically, alendronate users were mostly associated with AF as compared with distant past use of BP (OR, 1.97; 95% CI, 1.59-2.43).

CONCLUSION

In our nested case-control study, current users of BP are associated with a higher risk of atrial fibrillation as compared with those who had stopped BP treatment for more than 1 year.

Long-term efficacy, safety, and patient acceptability of ibandronate in the treatment of postmenopausal osteoporosis

Several second-generation bisphosphonates (BPs) are approved in osteoporosis treatment. Efficacy and safety depends on potency of farnesyl pyrophosphate synthase (FPPS) inhibition, hydroxyapatite affinity, compliance and adherence. The latter may be influenced by frequency and route of administration. A literature search using “ibandronate”, “postmenopausal osteoporosis”, “fracture”, and “bone mineral density” (BMD) revealed 168 publications. The Phase III BONE study, using low dose 2.5 mg daily oral ibandronate demonstrated 49% relative risk reduction (RRR) in clinical vertebral fracture after 3 years. Non-vertebral fracture (NVF) reduction was demonstrated in a subgroup (pretreatment T-score ≤ −3.0; RRR 69%) and a meta-analysis of high annual doses (150 mg oral monthly or intravenous equivalent of ibandronate; RRR 38%). Hip fracture reduction was not demonstrated. Long-term treatment efficacy has been confirmed over 5 years. Long term safety is comparable to placebo over 3 years apart from flu-like symptoms which are more common with oral monthly and intravenous treatments. No cases of atypical femoral fracture or osteonecrosis of the jaw have been reported in randomized controlled trial studies. Ibandronate inhibits FPPS more than alendronate but less than other BPs which could explain rate of action onset. Ibandronate has a higher affinity for hydroxyapatite compared with risedronate but less than other BPs which could affect skeletal distribution and rate of action offset. High doses (150 mg oral monthly or intravenous equivalent) were superior to low doses (oral 2.5 mg daily) according to 1 year BMD change. Data are limited by patient selection, statistical power, under-dosing, and absence of placebo groups in high dose studies. Ibandronate treatment offers different doses and modalities of administration which could translate into higher adherence rates, an important factor when the two main limitations of BP treatment are initiation and adherence rates. However, lack of consistency in NVF reduction and absence of hip fracture data limits more generalized use of this agent.

Bisphosphonate drug holidays: Can we recommend currently?

Bisphosphonates (BP) are the mainstay of treatment for osteoporosis. Subtrochanteric or diaphyseal fractures have been reported with long term use of BP, which raised world-wide debate on two aspects, i.e., for how long the BP is to be given and potential advantages/role of BP drug holidays. BP accumulates in bone with some persistent protective effect after therapy is stopped endorses the concept. Theoretically, a drug holiday may be a considerable option to decrease risks of BP, which continuing the protection from fractures but the level of evidence and data supporting the concept of drug holidays is a week. Hence, no specific recommendations are available on BP drug holidays from major available treatment guidelines on postmenopausal osteoporosis. Hence, before it is recommended it requires more robust research in this field.

Questioning the association between bisphosphonates and atypical femoral fractures

Bisphosphonates are the first-line treatment for osteoporosis. Structurally, they are stable analogues of pyrophosphate and therefore exhibit a high affinity for bone mineral. They reduce bone loss by attenuating the ability of the osteoclast to resorb bone, decreasing activation frequency, and the rate of remodeling. Large prospective randomized placebo-control trials provide unequivocal evidence for a reduction in the incidence of fractures. Impressively, 40 years since their first use in patients, the safety profile of bisphosphonates has been equally reassuring. Questions have arisen lately as to whether bisphosphonates could cause atypical fractures, a rare type of atraumatic or minimal trauma femur fracture occurring below the great trochanter. This question has prompted calls for a broader examination of the long-term effects of bisphosphonate use. An attempt by the Food and Drug Administration to garner consensus and provide definitive views was not successful. This has led to continued anxiety among treating physicians and patients alike, resulting in an overall reduction in prescriptions for bisphosphonates and for osteoporosis therapies in general. Here, we provide an overview of the current data on atypical fractures and bisphosphonate use.

Updates on mechanism of action and clinical efficacy of risedronate in osteoporosis

Risedronate is a heterocyclic orally active aminobisphosphonate and it belongs to the bisphosphonate category: these drugs are powerful bone resorption inhibitors, thanks to their affinity for hydroxyapatite crystals at bone mineral matrix level and to their inhibiting effects on osteoclast activity, using the ability of inhibiting enzyme FPPS. Recent observations have reported that risedronate can decrease resorption entity, not only of the trabecular bone, but also of the cortical bone, modifying therefore the (bone compact) thickness and the cortical porosity entity, which is largely responsible of femoral fracture especially among elderly patients. Various controlled studies have proved the efficacy of risedronate in reducing fragility fracture risk significantly. In particular, it is able to lower in a very significant way the incidence of vertebral, non-vertebral and femoral fractures, with precocity of effects after only six months of therapy. The extension of protocols, moreover, has marked its efficacy even after seven years of treatment. Under the metabolic profile, these studies have also shown that risedronate activity can reduce bone resorption markers and increase bone density values at lumbar and femoral level. Results emerged from a group of women aged over 80 are relevant: risedronate has proved capable of decreasing femoral fracture risk. Also in male and steroidal osteoporosis, clinical controlled studies have shown that risedronate is effective in decreasing vertebral fracture incidence. Lastly, tolerability: the main side effects concern the gastrointestinal tract and they are usually rare, of minor entity and can be solved by sospending the treatment. Acute phase reaction is rare, due to risedronate oral administration; it is also valid for osteonecrosis of the jaw and atypical fractures.

Challenges in implementing and maintaining osteoporosis therapy

In the United States, an estimated 19% of older men and 30% of older women are at elevated risk of osteoporotic fracture and considered to be eligible for treatment. The burden of osteoporosis is similar in Europe and is projected to rise worldwide, with aging populations and increasing fracture rates accompanying urbanization. Notwithstanding its high prevalence, osteoporosis is often underdiagnosed and undertreated. Moreover, even when the diagnosis is made and the decision is taken to treat, there are remaining challenges in implementing therapy for osteoporosis. Several patient populations are particularly challenging for clinicians to treat and require further study with regard to osteoporosis therapy. These include the very elderly, who face challenges relating to adherence; men, in whom osteoporosis remains under-recognized; patients with glucocorticoid-induced osteoporosis or renal impairment, who are at increased risk of fracture; patients with preexisting gastrointestinal problems who cannot tolerate existing orally administered osteoporosis therapies; and high-risk patients who show inadequate response to therapy. Moreover, poor adherence and poor persistence with osteoporosis medications are common and result in an increased risk of fracture, higher medical costs, and increased hospitalizations. Once the decision to institute therapy is made, patient education about osteoporosis and fracture risk should be provided. This is particularly important for men, who may not be aware that osteoporosis can be a concern. Secondary prevention programs, including fracture liaison services and bone therapy groups, can help to improve adherence to therapy. Further study is needed to guide the treatment of men, the very elderly, patients with glucocorticoid-induced osteoporosis and renal impairment, high-risk patients not well-controlled despite therapy, and patients with preexisting gastrointestinal conditions. Moreover, therapies are needed that are viewed as effective and safe by both physicians and patients, and as convenient to take by patients.

First Indian prospective randomized comparative study evaluating adherence and compliance of postmenopausal osteoporotic patients for daily alendronate, weekly risedronate and monthly ibandronate regimens of bisphosphonates

Aim:

The aim of the following study is to evaluate adherence and compliance of postmenopausal osteoporotic patients for different regimens of bisphosphonates (BP).

Materials and Methods:

A prospective observational randomized comparative 1 year study was undertaken to evaluate the adherence/compliance rates of most commonly prescribed daily alendronate (ALN), weekly risedronate (RIS) and monthly ibandronate (IBN) BP regimens.

Results:

Nearly 40% was the 1 year adherence rate with BP and 41.33% of non-compliance. Whereas, 8.66% was interrupted compliance rate and 6% switched over to other anti-osteoporotic treatment. The three treatment arm did not vary significantly. However, numerically maximum adherence rate of 56% was recorded in monthly BP regimen followed by weekly (36%) and daily regimen (32%). Medication possession rate confirmed on a follow-up visit was maximum with monthly regimen as 84.61% followed by daily (62.5%) and weekly (61.11%) respectively. Average time in days for non-adherence was 48, 56 and 92 day with daily ALN, weekly RIS and monthly IBN regimen respectively. Age, mean age at menopause, demographical profile failed to influence the adherence. Concomitant treatment for co-morbid condition (57.14%), unawareness about osteoporosis (OP) (50%), cost of treatment (45.33%), belief that drugs is for their general disability (39.28%), physician's failure to stress the need and necessary calcium + vitamin D daily requirement (23.80%) each were the most prevalent factors responsible for non-adherence. Intolerance and adverse drug reactions were responsible for only 13.09% and 11.90% of non-adherence.

Conclusion:

Treatment compliance is poor with daily ALN, weekly RIS and monthly IBN regimen along with calcium and vitamin D3 in Indian paramedical workers suffering OP.

Differences in In Vitro Disintegration Time among Canadian Brand and Generic Bisphosphonates

The objective of this study was to compare the disintegration times among Canadian-marketed brand (alendronate 70 mg, alendronate 70 mg plus vitamin D 5600 IU, and risedronate 35 mg) and generic (Novo-alendronate 70 mg and Apo-alendronate 70 mg) once-weekly dosed bisphosphonates. All disintegration tests were performed with a Vanderkamp Disintegration Tester. Disintegration was deemed to have occurred when no residue of the tablet, except fragments of insoluble coating or capsule shell, was visible. Eighteen to 20 samples were tested for each bisphosphonate group. The mean (±standard deviation) disintegration times were significantly (P < 0.05) faster for Apo-alendronate (26 ± 5.6 seconds) and Novo-alendronate (13 ± 1.1 seconds) as compared to brand alendronate (147 ± 50.5 seconds), brand alendronate plus vitamin D (378 ± 60.5 seconds), or brand risedronate (101 ± 20.6 seconds). The significantly faster disintegration of the generic tablets as compared to the brand bisphosphonates may have concerning safety and effectiveness implications for patients administering these therapies.

Eliminating the need for fasting with oral administration of bisphosphonates

Bisphosphonates are the major treatment of choice for osteoporosis, given that they are attached preferentially by bone and significantly reduce the risk of fractures. Oral bisphosphonates are poorly absorbed (usually less than 1% for nitrogen-containing bisphosphonates) and when taken with food or beverages create complexes that cannot be absorbed. For this reason, they must be taken on an empty stomach, and a period of up to 2 hours must elapse before the consumption of any food or drink other than plain water. This routine is not only inconvenient but can lead to discontinuation of treatment, and when mistakenly taken with food, may result in misdiagnosis of resistance to or failure of treatment. The development of an enteric-coated delayed-release formulation of risedronate with the addition of the calcium chelator, ethylenediaminetetraacetic acid (EDTA), a widely used food stabilizer, eliminates the need for fasting without affecting the bioavailability of risedronate or its efficacy.

A drinkable formulation of alendronate: potential to increase compliance and decrease upper GI irritation

Osteoporosis is a growing public health problem and several drugs have been developed in the past two decades to offer pharmacological solutions both in prevention and in therapy. Alendronate was the first compound registered as an anti-fracture agent and also the most prescribed drug worldwide for osteoporosis. Patient compliance is a major problem with alendronate, with studies demonstrating that 50-60% of patients discontinue treatment within one year. Dysphagia and swallowing difficulties are common especially among elderly people and the perceived potential for upper GI problems is a barrier to good long-term adherence. As non-persistence and non-compliance are linked to increased risk of fractures, efforts have been made to develop forms of alendronate which are more acceptable to patients. Among these, the drinkable formulations have the potential great convenience, simplicity of administration and reduction in gastro-intestinal side effects. In addition these novel soluble products are equivalent in cost to generic alendronate tablets. The approaches to improve adherence to an old and effective medication for osteoporotic patients will be reviewed in this report, with a special focus on the recently marketed product Bonasol 70 mg oral solution.

Incidence of fractures of the femur, including subtrochanteric, up to 8 years since initiation of oral bisphosphonate therapy: a register-based cohort study using the US MarketScan claims databases

In a cohort study of users of bisphosphonates, we evaluated the incidence of fragility fractures at all sites on the femur following for up to 8 years of therapy with alendronate or risedronate. We did not find evidence for a reversal of fracture protection with long-term use of bisphosphonates.

INTRODUCTION

Few studies have acquired adequate data with prolonged follow-up on bisphosphonate users in the general population to evaluate their long-term effects on the risk of hip fractures including those in the subtrochanteric region.

METHODS

This cohort study utilizes a large USA database (January 1, 2000 to June 30, 2009). We compared patients with higher versus lower degrees of compliance [medication possession ratio, MPR <1/3 (the reference), 1/3-<2/3, or ≥ 2/3]. Radiographic adjudication of fracture site and features were not performed. Hazard ratios (HR) for fracture were estimated using time-dependent Cox models. Restricted cubic splines (RCS) were used to plot HRs for fracture against duration of therapy.

RESULTS

There were 3,655 incident cases of femoral fracture (764 subtrochanteric/shaft, 2,769 hip) identified during 917,741 person-years of follow-up (median  =  3 years) on 287,099 patients (267,374 were women) from the date when they initiated oral bisphosphonate therapy. The corresponding HRs (95% confidence interval, CI) for overall femoral fractures associated with each additional year of therapy were 0.93 (0.86-1.01) within 5 years, and 0.89 (0.77-1.03) beyond 5 years for risedronate and 0.86 (0.81-0.91) and 0.95 (0.84-1.07) for alendronate, respectively. The corresponding estimates for subtrochanteric/shaft fractures were 1.05 (0.87-1.26) and 0.89 (0.60-1.33) for risedronate and 0.99 (0.92-1.05) and 1.05 (0.92-1.20) for alendronate, respectively. The HRs (95% CI) for overall femoral fractures associated with each additional year of alendronate or risedronate therapy within 5 and beyond 5 years were not significantly different.

CONCLUSION

Our study showed persistence of overall hip fracture protection with long-term use of alendronate or risedronate.

A mechanical model for predicting the probability of osteoporotic hip fractures based in DXA measurements and finite element simulation

BACKGROUND

Osteoporotic hip fractures represent major cause of disability, loss of quality of life and even mortality among the elderly population. Decisions on drug therapy are based on the assessment of risk factors for fracture, from BMD measurements. The combination of biomechanical models with clinical studies could better estimate bone strength and supporting the specialists in their decision.

METHODS

A model to assess the probability of fracture, based on the Damage and Fracture Mechanics has been developed, evaluating the mechanical magnitudes involved in the fracture process from clinical BMD measurements. The model is intended for simulating the degenerative process in the skeleton, with the consequent lost of bone mass and hence the decrease of its mechanical resistance which enables the fracture due to different traumatisms. Clinical studies were chosen, both in non-treatment conditions and receiving drug therapy, and fitted to specific patients according their actual BMD measures. The predictive model is applied in a FE simulation of the proximal femur. The fracture zone would be determined according loading scenario (sideway fall, impact, accidental loads, etc.), using the mechanical properties of bone obtained from the evolutionary model corresponding to the considered time.

RESULTS

BMD evolution in untreated patients and in those under different treatments was analyzed. Evolutionary curves of fracture probability were obtained from the evolution of mechanical damage. The evolutionary curve of the untreated group of patients presented a marked increase of the fracture probability, while the curves of patients under drug treatment showed variable decreased risks, depending on the therapy type.

CONCLUSION

The FE model allowed to obtain detailed maps of damage and fracture probability, identifying high-risk local zones at femoral neck and intertrochanteric and subtrochanteric areas, which are the typical locations of osteoporotic hip fractures.The developed model is suitable for being used in individualized cases. The model might better identify at-risk individuals in early stages of osteoporosis and might be helpful for treatment decisions.

Denosumab, a RANK ligand inhibitor, for the management of bone loss in cancer patients

Bone loss is a common side effect of cancer treatments, especially antihormonal treatments used in the treatment of breast and prostate cancer. Denosumab is a monoclonal antibody given subcutaneously that inhibits osteoclast activity by targeting the RANK ligand. It is effective in settings ranging from preventing skeletal-related complications in cancer patients with metastatic disease to increasing bone mineral density in patients with osteoporosis. In cancer patients with early stage disease, denosumab can attenuate bone loss from antihormonal treatments, and in prostate cancer, may reduce disease progression. Here, we will discuss the important role denosumab may play in the management of bone loss in patients with cancer.

Three-year experience with alendronate treatment in postmenopausal osteoporotic Japanese women with or without renal dysfunction: a retrospective study

BACKGROUND AND OBJECTIVE

Chronic kidney disease is associated with an increased risk of fragility fractures. A retrospective study was conducted to compare outcomes after 3 years of alendronate treatment in postmenopausal osteoporotic Japanese women with or without renal dysfunction (RD).

METHODS

One hundred and thirty-five postmenopausal osteoporotic Japanese women (mean age at baseline: 68 years) who had been treated with alendronate in our outpatient clinic for more than 3 years were analysed. The lumbar spine bone mineral density (BMD) of patients was measured using dual energy x-ray absorptiometry, and urinary levels of cross-linked N-terminal telopeptides of type I collagen (NTX) and serum levels of alkaline phosphatase (ALP) were monitored during the 3-year treatment period. The incidence of osteoporotic fractures was also assessed.

RESULTS

Twenty-six women had RD with an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2. The urinary NTX and serum ALP levels significantly decreased and the lumbar spine BMD significantly increased, compared with the baseline values, in a manner that was similar among women with or without RD. However, the incidence of non-vertebral fractures, but not that of vertebral fractures, was significantly higher among women with RD than among women without RD.

CONCLUSIONS

Alendronate treatment appeared to have a similar effect on surrogate markers in postmenopausal osteoporotic Japanese women with or without RD. However, further studies are needed to confirm that RD may increase the risk of non-vertebral fractures in patients treated with alendronate.

Extraskeletal benefits and risks of calcium, vitamin D and anti-osteoporosis medications

Drugs used for the prevention and the treatment of osteoporosis exert various favourable and unfavourable extra-skeletal effects whose importance is increasingly recognized notably for treatment selection.

INTRODUCTION

The therapeutic armamentarium for the prevention and the treatment of osteoporosis is increasingly large, and possible extra-skeletal effects of available drugs could influence the choice of a particular compound.

METHODS

The present document is the result of a national consensus, based on a systematic and critical review of the literature.

RESULTS

Observational research has suggested an inverse relationship between calcium intake and cardiovascular diseases, notably through an effect on blood pressure, but recent data suggest a possible deleterious effect of calcium supplements on cardiovascular risk. Many diverse studies have implicated vitamin D in the pathogenesis of clinically important non-skeletal functions or diseases, especially muscle function, cardiovascular disease, autoimmune diseases and common cancers. The possible effects of oral or intravenous bisphosphonates are well-known. They have been associated with an increased risk of oesophageal cancer or atrial fibrillation, but large-scale studies have not found any association with bisphosphonate use. Selective oestrogen receptor modulators have demonstrated favourable or unfavourable extra-skeletal effects that vary between compounds. Strontium ranelate has a limited number of non-skeletal effects. A reported increase in the risk of venous thromboembolism is not found in observational studies, and very rare cases of cutaneous hypersensitivity reactions have been reported. Denosumab has been introduced recently, and its extra-skeletal effects still have to be assessed.

CONCLUSION

Several non-skeletal effects of bone drugs are well demonstrated and influence treatment choices.

Bazedoxifene: a review of its use in the treatment of postmenopausal osteoporosis

Bazedoxifene (Conbriza®, Viviant®) is the first third-generation selective estrogen receptor modulator (SERM) and it is approved for the treatment of postmenopausal osteoporosis in the EU and Japan. Bazedoxifene contains an indole-based core binding domain that binds with high affinity to estrogen receptors and exhibits favourable effects on bone and lipid profiles, with no clinically relevant endometrial or breast stimulation. Oral bazedoxifene once daily reduced the incidence of new vertebral fractures in patients with postmenopausal osteoporosis in a large, well designed trial of 3 years' duration; both bazedoxifene and raloxifene were significantly more effective than placebo. Neither bazedoxifene nor raloxifene reduced the incidence of nonvertebral fractures in the overall study population; however, bazedoxifene, but not raloxifene, reduced the rate of nonvertebral fractures in high-risk patients. Moreover, data from patients who continued to receive the drug during a 2-year extension phase of this trial indicate that bazedoxifene continues to provide protection against new vertebral fractures for up to 5 years. Bazedoxifene also increases bone mineral density and reduces the levels of bone turnover markers. Bazedoxifene was generally well tolerated and did not detrimentally affect the reproductive tract or breast tissue in clinical trials, thereby demonstrating a favourable risk-benefit profile. A pharmacoeconomic analysis conducted from an EU perspective predicted bazedoxifene to be cost effective in some EU countries. Therefore, bazedoxifene presents another useful option for the treatment of postmenopausal osteoporosis, especially in those at high risk for osteoporotic fracture.

Risedronate's Role in Reducing Hip Fracture in Postmenopausal Women with Established Osteoporosis

Osteoporosis is a significant concern for postmenopausal women and is a critical factor in hip fracture. Examining evidence for osteoporosis medications in hip fracture is important for optimizing treatment.

PURPOSE

Review risedronate's role for hip fracture in postmenopausal women.

METHODS

A literature search was conducted using Medline and Web of Science. The search was limited using the terms "risedronate" and "hip fracture," and to studies that included women. Similar articles linked to the search and pertinent articles in bibliographies were also examined.

RESULTS

Risedronate has demonstrated efficacy and cost effectiveness for hip fracture, but may not be beneficial for patients with low fracture risk. Risedronate is generally well tolerated, but may cause side effects in some patient populations.

CONCLUSION

Risedronate has benefit for hip fracture, but patients should be carefully screened to determine the appropriateness of risedronate before starting treatment.

BISPHOSPHONATE-INDUCED MAXILLOFACIAL OSTEONECROSIS IN OSTEOPOROTIC INDIVIDUALS

Bisphosphonate-related osteonecrosis of the maxillae may be an important complication of long-term osteoporosis treatment. The possibility of osteonecrosis of the maxillae in patients exposed to nitrogenated bisphosphonates was first described in 2003. Since then, case reports and retrospective studies have demonstrated higher percentages of occurrence of osteonecrosis in patients who have used or are using bisphosphonates. Although this complication may be spontaneous, invasive oral procedures have a role as risk factors associated with dental procedures such as tooth extractions and other bone operations. In addition, tooth infections and periodontal disease have been reported to be the main risk factors for development of bisphosphonate-induced osteonecrosis of the maxillae. For this reason, dentists, general clinicians, orthopedists, geriatricians and oral-maxillofacial surgeons need to be aware of this problem and work in a multidisciplinary environment, thereby stimulating early diagnosis and prevention of further potential cases.

Three-year experience with combined treatment with alendronate and alfacalcidol in Japanese patients with severe bone loss and osteoporotic fracture

Purpose:

Combined treatment with alendronate and alfacalcidol is more useful to increase bone mineral density (BMD) than alendronate or alfacalcidol alone. A retrospective study was conducted to investigate the 3-year outcome of combined treatment with alendronate and alfacalcidol in patients with severe bone loss (BMD ≤ 50% of the young adult mean) and osteoporotic fracture.

Methods:

Thirty-four patients (six men and 28 postmenopausal women) with primary or secondary osteoporosis who had been treated with alendronate and alfacalcidol for more than 3 years were analyzed. The lumbar spine or total hip BMD and bone turnover markers were monitored, and the incidence of osteoporotic fractures was assessed.

Results:

The urinary level of cross-linked N-terminal telopeptides of type I collagen and serum level of alkaline phosphatase significantly decreased (−42.5% at 3 months and −18.9% at 3 years), and the lumbar spine BMD, but not the total hip BMD, significantly increased (14.8% at 3 years), compared with the baseline values. However, the incidence of vertebral and nonvertebral fractures was 26.5% and 2.9%, respectively, suggesting a high incidence of vertebral fractures.

Conclusion:

The results of the present study suggest that combined treatment with alendronate and alfacalcidol may be useful to reduce bone turnover and increase the lumbar spine BMD in patients with severe bone loss and osteoporotic fracture. However, its efficacy against vertebral fractures appears not to be sufficient. Thus, anabolic agents such as teriparatide should be taken into consideration as first-line drugs in patients with severe osteoporosis.

Is bisphosphonate therapy for benign bone disease associated with impaired dental healing? A case-controlled study

Background

Bisphosphonates are common first line medications used for the management of benign bone disease. One of the most devastating complications associated with bisphosphonate use is osteonecrosis of the jaws which may be related to duration of exposure and hence cumulative dose, dental interventions, medical co-morbidities or in some circumstances with no identifiable aggravating factor. While jaw osteonecrosis is a devastating outcome which is currently difficult to manage, various forms of delayed dental healing may be a less dramatic and, therefore, poorly-recognised complications of bisphosphonate use for the treatment of osteoporosis. It is hypothesised that long-term (more than 1 year's duration) bisphosphonate use for the treatment of post-menopausal osteoporosis or other benign bone disease is associated with impaired dental healing.

Methods/Design

A case-control study has been chosen to test the hypothesis as the outcome event rate is likely to be very low. A total of 54 cases will be recruited into the study following review of all dental files from oral and maxillofacial surgeons and special needs dentists in Victoria where potential cases of delayed dental healing will be identified. Potential cases will be presented to an independent case adjudication panel to determine if they are definitive delayed dental healing cases. Two hundred and fifteen controls (1:4 cases:controls), matched for age and visit window period, will be selected from those who have attended local community based referring dental practices. The primary outcome will be the incidence of delayed dental healing that occurs either spontaneously or following dental treatment such as extractions, implant placement, or denture use.

Discussion

This study is the largest case-controlled study assessing the link between bisphosphonate use and delayed dental healing in Australia. It will provide invaluable data on the potential link between bisphosphonate use and osteonecrosis of the jaws.

Denosumab: a review of its use in the treatment of postmenopausal osteoporosis

Denosumab (Prolia®) is a human recombinant monoclonal antibody that is approved for the treatment of postmenopausal osteoporosis in women at high or increased risk of fracture in the US, the EU and several other countries. Denosumab has a novel mechanism of action; it binds to receptor activator of nuclear factor κB ligand and inhibits bone resorption by inhibiting osteoclast formation, function and survival. In postmenopausal women with osteoporosis, denosumab reduced the risk of vertebral, nonvertebral and hip fractures compared with placebo over 3 years in the large, phase III FREEDOM study. In postmenopausal women with low bone mineral density (BMD) or osteoporosis, treatment with denosumab increased BMD and decreased markers of bone turnover more than alendronate in those who were essentially treatment-naive in the 1-year DECIDE study and also in the 1-year STAND study, in which women were switched from alendronate to denosumab or continued alendronate treatment. Denosumab was generally well tolerated in clinical trials, although long-term effects of very low bone turnover remain to be established. Denosumab is administered once every 6 months via subcutaneous injection, which may be a preferred method of administration and may improve adherence to treatment compared with other osteoporosis treatments. Denosumab is a valuable new option for the treatment of postmenopausal osteoporosis in women at increased or high risk of fractures, and may be useful as a first-line treatment in women at increased risk of fractures who are unable to take other osteoporosis treatments.

Atrial fibrillation and the use of oral bisphosphonates

Background:

Epidemiological studies investigating a possible association between bisphosphonates and atrial fibrillation (AF) have reported conflicting findings. The objective of our study was to determine whether exposure to oral nitrogen-containing bisphosphonates alendronate and risedronate are associated with increased incidence of atrial fibrillation.

Methods:

In a retrospective cohort study we analyzed data from three large independent databases, two from the United States (MarketScan^® and Ingenix^®) and one from the United Kingdom (THIN). 144,548 women, age 50–89, bisphosphonate users during 2002–2005 were compared to 668,891 sex- and age-matched controls (1:4). Our primary outcome measure was new incident atrial fibrillation for up to three years; Cox models adjusted for disease and drug history were used to estimated relative risks.

Results:

We identified a total of 8,001, 1,984, and 817 AF cases in oral bisphosphonate users and nonusers during 744,340 (MarketScan), 243,898 (Ingenix), and 148,779 (THIN) person-years of follow-up, respectively. Compared to nonusers, overall adjusted relative risk (adjRR) (95% confidence interval [CI]) for AF in oral bisphosphonates users was 0.92 (0.85–0.99; MarketScan), 1.00 (0.87–1.16; Ingenix), and 0.97 (0.79–1.20; THIN); overall adjRR (95% CI) for any cardiac dysrrhythmia for MarketScan was 1.01 (0.98–1.05), Ingenix 1.06 (0.99–1.13), and THIN 0.97 (0.79–1.20).

Conclusions:

In all three databases from the two countries, the risk of AF or cardiac dysrrhythmia was not increased in postmenopausal women treated for up to three years with oral alendronate or risedronate.

The facial skeleton in patients with osteoporosis: a field for disease signs and treatment complications

Osteoporosis affects all bones, including those of the facial skeleton. To date the facial bones have not drawn much attention due to the minimal probability of morbid fractures. Hearing and dentition loss due to osteoporosis has been reported. New research findings suggest that radiologic examination of the facial skeleton can be a cost-effective adjunct to complement the early diagnosis and the follow up of osteoporosis patients. Bone-mass preservation treatments have been associated with osteomyelitis of the jawbones, a condition commonly described as osteonecrosis of the jaws (ONJ). The facial skeleton, where alimentary tract mucosa attaches directly to periosteum and teeth which lie in their sockets of alveolar bone, is an area unique for the early detection of osteoporosis but also for the prevention of treatment-associated complications. We review facial bone involvement in patients with osteoporosis and we present data that make the multidisciplinary approach of these patients more appealing for both practitioners and dentists. With regard to ONJ, a tabular summary with currently available evidence is provided to facilitate multidisciplinary practice coordination for the treatment of patients receiving bisphosphonates.

Bisphosphonate use and hip fracture epidemiology: ecologic proof from the contrary

AIM

The objective of this article is to evaluate the relationship between the changes in prescriptions of antiosteoporotic drugs (mainly the rapid fall in the use of bisphosphonates [BPs]) and standardized hip fracture (HF) rates over the period 2005-2008 in the Australian Capital Territory (ACT).

METHODS

Annual sex- and age-specific HF rates (per 100,000 population) were determined and standardized using the Australian 2006 population census. Data on the annual prescriptions of BPs (mainly alendronate and risedronate), strontium ranelate, and hormone replacement therapy were obtained from the Australian Pharmaceutical Benefits Scheme (PBS) and Repatriation Australian Pharmaceutical Benefits Scheme (RPBS) databases.

RESULTS

In the ACT, the peak annual number of prescriptions for BPs was observed in 2006. Following reports linking osteonecrosis of the jaw with BP use, the number of BP prescriptions dropped by 14% in 2007-2008 compared with 2005, when the lowest HF rates were recorded. The reduction in BP prescriptions coincided with increased HF rates in females in 2007 (+22.6%) and in 2008 (+25.2%) compared with 2005; in males, HF incidence declined by 6.6% and 16.7%, respectively. The proportion of filled prescriptions for strontium ranelate, risedronate, and alendronate in 2007-2008 was 1:8.4:15.5, indicating that BPs were the dominant antiosteoporotic drugs. There was an inverse statistically significant relationship between the total annual number of BP prescriptions and standardized HF incidence rates for the 10-year period 1999-2008.

CONCLUSION

Although currently there is no clear understanding of factors contributing to changing HF epidemiology, the available evidence suggests that much of the decline in HF rates is due to the use of BPs. The fall in the use of BPs is associated with an increase in HF rates in females, indicating that BPs should still be considered the first-line medications for the prevention and treatment of osteoporosis. Our results need to be confirmed in other populations and countries.