Adherence with intravenous zoledronate and intravenous ibandronate in the United States Medicare population

Bisphosphonate alternative regimens for the prevention of osteoporotic fragility fractures: BLAST-OFF, a mixed-methods study

Background

Bisphosphonates are a class of medication commonly used to treat osteoporosis. Alendronate is recommended as the first-line treatment; however, long-term adherence (both treatment compliance and persistence) is poor. Alternative bisphosphonates are available, which can be given intravenously and have been shown to improve long-term adherence. However, the most clinically effective and cost-effective alternative bisphosphonate regimen remains unclear. What is the most cost-effective bisphosphonate in clinical trials may not be the most cost-effective or acceptable to patients in everyday clinical practice.

Objectives

1. Explore patient, clinician and stakeholder views, experiences and preferences of alendronate compared to alternative bisphosphonates. 2. Update and refine the 2016 systematic review and cost-effectiveness analysis of bisphosphonates, and estimate the value of further research into their benefits. 3. Undertake stakeholder/consensus engagement to identify important research questions and further rank research priorities.

Methods

The study was conducted in two stages, stages 1A and 1B in parallel, followed by stage 2: • Stage 1A - we elicited patient and healthcare experiences to understand their preferences of bisphosphonates for the treatment of osteoporosis. This was undertaken by performing a systematic review and framework synthesis of qualitative studies, followed by semistructured qualitative interviews with participants. • Stage 1B - we updated and expanded the existing Health Technology Assessment systematic review and clinical and cost-effectiveness model, incorporating a more comprehensive review of treatment efficacy, safety, side effects, compliance and long-term persistence. • Stage 2 - we identified and ranked further research questions that need to be answered about the effectiveness and acceptability of bisphosphonates.

Results

Patients and healthcare professionals identified a number of challenges in adhering to bisphosphonate medication, balancing the potential for long-term risk reduction against the work involved in adhering to oral alendronate. Intravenous zoledronate treatment was generally more acceptable, with such regimens perceived to be more straightforward to engage in, although a portion of patients taking alendronate were satisfied with their current treatment. Intravenous zoledronate was found to be the most effective, with higher adherence rates compared to the other bisphosphonates, for reducing the risk of fragility fracture. However, oral bisphosphonates are more cost-effective than intravenous zoledronate due to the high cost of zoledronate administration in hospital. The importance of including patients and healthcare professionals when setting research priorities is recognised. Important areas for research were related to patient factors influencing treatment selection and effectiveness, how to optimise long-term care and the cost-effectiveness of delivering zoledronate in an alternative, non-hospital setting.

Conclusions

Intravenous zoledronate treatment was generally more acceptable to patients and found to be the most effective bisphosphonate and with greater adherence; however, the cost-effectiveness relative to oral alendronate is limited by its higher zoledronate hospital administration costs.

Future work

Further research is needed to support people to make decisions influencing treatment selection, effectiveness and optimal long-term care, together with the clinical and cost-effectiveness of intravenous zoledronate administered in a non-hospital (community) setting.

Limitations

Lack of clarity and limitations in the many studies included in the systematic review may have under-interpreted some of the findings relating to effects of bisphosphonates.

Trial registration

This trial is registered as ISRCTN10491361.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR127550) and is published in full in Health Technology Assessment; Vol. 28, No. 21. See the NIHR Funding and Awards website for further award information.

Methodological guidance for the use of real-world data to measure exposure and utilization patterns of osteoporosis medications

Observational studies of osteoporosis medications can provide critical real-world evidence (RWE) that fills knowledge gaps left by clinical trials. However, careful consideration of study design is needed to yield reliable estimates of association. In particular, obtaining valid measurements of exposure to osteoporosis medications from real-world data (RWD) sources is complicated due to different medication classes, formulations, and routes of administration, each with different pharmacology. Extended half-lives of bisphosphonates and extended dosing of denosumab and zoledronic acid require particular attention. In addition, prescribing patterns and medication taking behavior often result in gaps in therapy, switching, and concomitant use of osteoporosis therapies. In this review, we present important considerations and provide specialized guidance for measuring osteoporosis drug exposures in RWD. First, we compare different sources of RWD used for osteoporosis drug studies and provide guidance on identifying osteoporosis medication use in these data sources. Next, we provide an overview of osteoporosis pharmacology and how it can influence decisions on exposure measurement within RWD. Finally, we present considerations for the measurement of osteoporosis medication exposure, adherence, switching, long-term exposures, and drug holidays using RWD. Ultimately, a thorough understanding of the differences in RWD sources and the pharmacology of osteoporosis medications is essential to obtain valid estimates of the relationship between osteoporosis medications and outcomes, such as fractures, but also to improve the critical appraisal of published studies.

Predicting the acute-phase response fever risk in bisphosphonate-naive osteoporotic patients receiving their first dose of zoledronate

INTRODUCTION

To devise a precise and efficient tool for predicting the individualized risk of acute-phase response (APR) in bisphosphonate (BP)-naive osteoporotic (OP) patients, receiving their first intravenous dose of zoledronate (ZOL).

METHODS

The baseline clinical and laboratory data of 475 consecutive BP-naive OP patients, who received their first intravenous dose of ZOL between March 2016 and March 2021 in the Affiliated Kunshan Hospital of Jiangsu University, were chosen for analysis. Univariate and multivariable logistic regression models were generated to establish candidate predictors of APR fever risk, using three distinct fever thresholds, namely, 37.3 °C (model A), 38.0 °C (model B), and 38.5 °C (model C). Next, using predictor regression coefficients, three fever-threshold nomograms were developed. Discrimination, calibration, and clinical usefulness of each predicting models were then assessed using the area under the curve (AUC), calibration curve (CC), and decision curve analysis (DCA). The internal and external model validations were then performed.

RESULTS

The stable predictors were age, serum 25-hydroxy vitamin D, serum total calcium, and peripheral blood erythrocytes count. These were negatively associated with the APR fever risk. The AUCs of models A, B, and C were 0.828 (95% confidence intervals [CI], 0.782 to 0.874), 0.825 (95% CI, 0.767 to 0.883), and 0.879 (95% CI, 0.824 to 0.934), respectively. Good agreement was observed between the predictions and observations in the CCs of all three nomograms.

CONCLUSIONS

This study developed and validated nomogram prediction models that can predict APR fever risk in BP-naive OP patients receiving their first infusion of ZOL.

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.

The Promise of Improved Adherence With Long-Acting Antiretroviral Therapy: What Are the Data?

As with other chronic conditions, adherence to daily medications remains a challenge for many individuals living with HIV due to structural, behavioral, and social barriers. Unfortunately, high levels of adherence to antiretroviral therapy are required to maintain virologic suppression. Alternative approaches are being explored to decrease the burden of daily pill administration, including long-acting injectable, oral, and implantable products. Phase 3 data support the efficacy of nanoformulated injectable cabotegravir and rilpivirine for HIV treatment in patients with undetectable viremia, but we have yet to learn how this strategy may benefit those with medication adherence challenges. Despite this, the affected community and HIV providers are very interested in exploring the role of long-acting therapies to address some types of barriers to medication adherence. This review summarizes available information about the potential for long-acting therapy to improve adherence for some patients and outlines associated opportunities and challenges with the implementation of long-acting therapy for the treatment and prevention of HIV.

Persistence and adherence to parenteral osteoporosis therapies: a systematic review

Osteoporosis is a chronic disease of low bone mass and fragility. Treatment is frequently compromised by suboptimal medication compliance causing increased morbidity. This review investigates adherence and persistence to parenteral osteoporosis therapies. Findings reveal parenteral medications requiring reduced dosing frequency have higher compliance than oral therapies. This systematic review examines real-world adherence to parenteral osteoporosis therapies. We searched PubMed, Medline, and EMBASE databases for English language observational studies that examined patient adherence and/or persistence to parenteral osteoporosis treatments (teriparatide sc, ibandronate iv, zoledronic acid iv, and denosumab sc) in adults with osteoporosis published up to September 2018. Studies with only self-reported adherence or persistence data and those with less than 20 patients were excluded. Quality assessment of included studies was completed using the Newcastle-Ottawa quality assessment scale (NOS). We identified 40 eligible studies. Teriparatide was examined in 29 studies, with persistence rates of 10-87% (median 55%) at 1 year and 10-69% (median 29.5%) at 2 years, and adherence rates of 21-89% (median 53%) at 1 year and 37-68% (median 40%) at 2 years. Ten studies of zoledronic acid reported persistence rates of 34-73% (median 42%) for second dose and 20-54% (median 35.8%) for third dose. Ten studies of ibandronate adherence reported and 2-year persistence rates of 31-58% (median 47.5%) in 1 year and 13-35% (median 25%) at 2 years, and adherence rates of 21-72% (median 47.3%) and 15-58% (median 36.5%) respectively. Denosumab was reported in 19 studies, with second (1 year) and fourth (2 year) dose persistence rates of 61-100% (median 81%) and 36-99% (median 45.5%). There is substantial heterogeneity in reports of persistence and adherence rates with parenteral osteoporosis therapies. Most of the published data are from short-term studies and evaluations of long-term adherence and persistence with parenteral therapies for osteoporosis are needed.

A systematic review of factors affecting medication adherence among patients with osteoporosis

The aim of this review was to identify factors that influence patients' adherence to anti-osteoporotic therapy. Factors identified that were associated with poorer medication adherence included polypharmacy, older age, and misconceptions about osteoporosis. Physicians need to be aware of these factors so as to optimize therapeutic outcomes for patients.

INTRODUCTION

To identify factors that influence patients' adherence to anti-osteoporotic therapy.

METHODS

A systematic review of literature was performed for articles published up till January 2018 using PubMed®, PsychINFO®, Embase®, and CINAHL®. Peer-reviewed articles which examined factors associated with anti-osteoporotic medication adherence were included. Classes of anti-osteoporotic therapy included bisphosphonates, parathyroid hormone-related analogue, denosumab, selective estrogen receptor modulators, estrogen/progestin therapy, calcitonin, and strontium ranelate. Meta-analyses, case reports/series, and other systematic reviews were excluded. Identified factors were classified using the World Health Organization's five dimensions of medication adherence (condition, patient, therapy, health-system, and socio-economic domains).

RESULTS

Of 2404 articles reviewed, 124 relevant articles were identified. The prevalence of medication adherence ranged from 12.9 to 95.4%. Twenty-four factors with 139 sub-factors were identified. Bisphosphonates were the most well-studied class of medication (n = 59, 48%). Condition-related factors that were associated with poorer medication adherence included polypharmacy, and history of falls was associated with higher medication adherence. Patient-related factors which were associated with poorer medication adherence included older age and misconceptions about osteoporosis while therapy-related factors included higher dosing frequency and medication side effects. Health system-based factors associated with poorer medication adherence included care under different medical specialties and lack of patient education. Socio-economic-related factors associated with poorer medication adherence included current smoker and lack of medical insurance coverage.

CONCLUSION

This review identified factors associated with poor medication adherence among osteoporotic patients. To optimize therapeutic outcomes for patients, clinicians need to be aware of the complexity of factors affecting medication adherence.

Adherence and preference of intravenous zoledronic acid for osteoporosis versus other bisphosphonates

Objective

To evaluate adherence as well as patient preference and satisfaction of once-yearly intravenous zoledronic acid versus other bisphosphonates treatments.

Methods

In accordance with the PRISMA guidelines, a systematic literature search was conducted in PubMed, Cochrane Library and EMBASE databases, over the date range of 2000-2016. Following the PICO (Population, Interventions, Comparator, Outcomes) elements, eligibility criteria included: (1) participants: adults over 18 with osteoporosis and adults who were at high risk of developing low bone density as a result of chronic use of glucocorticoids; (2) intervention: adherence or patient preference/satisfaction of once-yearly zoledronic acid treatment; (3) comparator: other bisphosphonates; (4) outcome: data about adherence, persistence, compliance, preference and satisfaction criteria. Specific exclusion criteria were also applied.

Results

Adherence to zoledronate is only quantified in one study showing that mean proportion of days covered for zoledronic acid was greater than for ibandronate users. Three studies showed 100% of compliance to zoledronate treatment and only one study showed zoledronic acid provided the highest persistence rates. Once-yearly intravenous infusion of zoledronic acid was clearly preferred. Only one article indicated preference for schedules that were once monthly or less frequent and other preference results practically equal between once-yearly intravenous infusion or weekly oral. Although there is little evidence, adherence to osteoporosis treatment is improved with annual intravenous zoledronate regimen. Moreover, patients appear to have preference for less frequent dosing. Switching from oral to intravenous therapy, based on the opportunities offered by an integrated health management area, may allow obtaining better outcomes in adherence to osteoporosis treatment.

Sequential treatment with zoledronic acid followed by teriparatide or vice versa increases bone mineral density and bone strength in ovariectomized rats

Bisphosphonates (BPs) and teriparatide (TPTD) are both effective treatments for osteoporosis, but BP treatment prior to daily TPTD treatment has been shown to impair the effect of TPTD in some clinical studies. In contrast, the loss of bone mineral density (BMD) that occurs after withdrawal of TPTD can be prevented by BP treatment. Although various studies have investigated the combination and/or sequential use of BP and TPTD, there have been no clinical studies investigating sequential treatment with zoledronic acid (ZOL) and TPTD (or vice versa). In this study, we evaluated the effects of sequential treatment with TPTD followed by ZOL, and ZOL followed by TPTD, using ovariectomized (OVX) rats. Two months after OVX, osteopenic rats were treated with ZOL, TPTD, or vehicle for a period of 4 months (first treatment period), and then the treatments were switched and administered for another 4 months (second treatment period). The group treated with ZOL followed by TPTD showed an immediate increase in BMD of the proximal tibia and greater BMD and bone strength of the lumbar vertebral body, femoral diaphysis, and proximal femur than the group treated with ZOL followed by vehicle. Serum osteocalcin, a marker of bone formation, increased rapidly after switching to TPTD from ZOL. The group treated with TPTD followed by ZOL did not lose BMD in the proximal tibia after TPTD was stopped, while the group treated with TPTD followed by vehicle did lose BMD. The BMD and bone strength of the lumbar vertebral body, femoral diaphysis, and proximal femur were greater in the group treated with TPTD followed by ZOL than in the group treated with TPTD followed by vehicle. The increase in serum osteocalcin and urinary CTX after withdrawal of TPTD was prevented by the switch from TPTD to ZOL. In conclusion, our results demonstrate that switching from ZOL to TPTD resulted in a non-attenuated anabolic response in the lumbar spine and femur of OVX rats. In addition, switching from TPTD to ZOL caused BMD to be maintained or further increased. If these results can be reproduced in a clinical setting, the sequential use of ZOL followed by TPTD or vice versa in the treatment of osteoporosis patients would contribute to increases in BMD that, hopefully, would translate into a corresponding decrease in the incidence of vertebral and non-vertebral fractures.

Frequency of discontinuation of injectable osteoporosis therapies in US patients over 2 years

Little is known about treatment patterns with injectable osteoporosis therapies. At 12 months, the probability of discontinuation was 69.1% among patients using ibandronate, followed by teriparatide (67.1%), zoledronic acid (59.2%), and denosumab (48.8%). By 24 months, discontinuation was higher for each treatment. The majority of US patients discontinue injectable osteoporosis treatment by the end of the first year following initiation.

INTRODUCTION

This study was designed to assess the frequency of treatment discontinuation over time among patients who initiate injectable osteoporosis therapies.

METHODS

This retrospective observational study utilized an administrative claims database to measure discontinuation of injectable osteoporosis therapy, reported at 6-month intervals over 2 years. Eligible patients were aged ≥55 years, had newly initiated injectable osteoporosis therapy between January 2008 and June 2012, and were continuously enrolled in the health plan for ≥1 year prior to and ≥1.5 years after the date the first injectable medication was received (the index date). Follow-up time ranged from 18 to 24 months. Injectable osteoporosis treatments included in the analysis were denosumab, ibandronate, teriparatide, and zoledronic acid. Discontinuation was assessed using Kaplan-Meier survival analysis and was defined at each time point as the percentage of patients who did not receive the dose scheduled for that time point. A 90-day grace period was allowed to accommodate flexibility in the scheduling of post-index re-administrations. Sensitivity analyses assessed discontinuation using grace periods of 60 and 30 days.

RESULTS

A total of 4756 patients met the inclusion criteria for the study, with 617 utilizing denosumab, 233 ibandronate, 778 teriparatide, and 3128 zoledronic acid. At 12 months, discontinuation was highest among patients using ibandronate (69.1%), followed by teriparatide (67.1%), zoledronic acid (59.2%), and denosumab (48.8%). By 24 months, discontinuation was higher for each treatment: 87.5% for ibandronate, 87.9% for teriparatide, 79.8% for zoledronic acid, and 64.3% for denosumab.

CONCLUSIONS

The majority of US patients discontinue injectable osteoporosis treatment by the end of the first year following initiation.

GRAND-4: the German retrospective analysis of long-term persistence in women with osteoporosis treated with bisphosphonates or denosumab

This retrospective database study assessed 2-year persistence with bisphosphonates or denosumab in a large German cohort of women with a first-time prescription for osteoporosis treatment. Compared with intravenous or oral bisphosphonates, 2-year persistence was 1.5-2 times higher and risk of discontinuation was significantly lower (P < 0.0001) with denosumab.

INTRODUCTION

Persistence with osteoporosis therapies is critical for fracture risk reduction. Detailed data on long-term persistence (≥2 years) with bisphosphonates and denosumab are sparse.

METHODS

From the German IMS® database, we included women aged 40 years or older with a first-time prescription for bisphosphonates or denosumab between July 2010 and August 2014; patients were followed up until December 2014. The main outcome was treatment discontinuation, with a 60-day permissible gap between filled prescriptions. Two-year persistence was estimated using Kaplan-Meier survival curves, with treatment discontinuation as the failure event. Denosumab was compared with intravenous (i.v.) and oral bisphosphonates separately. Cox proportional hazard ratios (HRs) for the 2-year risk of discontinuation were calculated, with adjustment for age, physician specialty, health insurance status, and previous medication use.

RESULTS

Two-year persistence with denosumab was significantly higher than with i.v. or oral bisphosphonates (39.8 % [n = 21,154] vs 20.9 % [i.v. ibandronate; n = 20,472] and 24.8 % [i.v. zoledronic acid; n = 3966] and 16.7-17.5 % [oral bisphosphonates; n = 114,401]; all P < 0.001). Patients receiving i.v. ibandronate, i.v. zoledronic acid, or oral bisphosphonates had a significantly increased risk of treatment discontinuation than did those receiving denosumab (HR = 1.65, 1.28, and 1.96-2.02, respectively; all P < 0.0001).

CONCLUSIONS

Two-year persistence with denosumab was 1.5-2 times higher than with i.v. or oral bisphosphonates, and risk of discontinuation was significantly lower with denosumab than with bisphosphonates. A more detailed understanding of factors affecting medication-taking behavior may improve persistence and thereby reduce rates of fracture.

The impact of preventive measures on the burden of femoral fractures - a modelling approach to estimating the impact of fall prevention exercises and oral bisphosphonate treatment for the years 2014 and 2025

BACKGROUND

Due to the demographic transition with a growing number of old and oldest-old persons the absolute number of fragility fractures is expected to increase in industrialized countries unless effective preventive efforts are intensified. The main causes leading to fractures are osteoporosis and falls. The aim of this study is to develop population based models of the potential impact of fall-prevention exercise and oral bisphosphonates over the coming decade.

METHODS

The German federal state of Bavaria served as the model population. Model interventions were limited to community-dwelling persons aged 65 years and older. Models are based on fall-prevention exercise being offered to all persons aged 70 to 89 years and oral bisphosphonate treatment offered to all persons with osteoporosis as defined by a T-score of ≤ - 2.5. Treatment effect sizes are estimated from meta-analyses. Reduction in all femoral fractures in the population of community-dwelling persons aged 65 years and older is the outcome of interest. A spreadsheet-based modelling approach was used for prediction.

RESULTS

In 2014, reduction of femoral fractures by 10 % required 21 % of all community-dwelling persons aged 70-89 to participate in fall-prevention exercise, or 37 % of those with osteoporosis to receive oral bisphosphonates. Without intervention, demographic changes will result in a 24 % increase in femoral fractures by 2025. To lower the increase of fractures between 2014 and 2025 to 10 %, fall-prevention-exercise participation rate needs to be 25 % and bisphosphonate treatment rates 41 %, whereas to hold the 2025 rates flat at 2014 rates require 43 % fall-prevention-exercises participation, and is not achievable using oral bisphosphonates.

CONCLUSIONS

Unrealistic high treatment and participation rates of the two analysed measures are needed to achieve substantial effects on the expected burden of femoral fractures at present and in the future.

Natural history, reasons for, and impact of low/non-adherence to medications for osteoporosis in a cohort of community-dwelling older women already established on medication: a 2-year follow-up study

Approximately 15 % of older women on oral medications for osteoporosis could be considered for alternatives including parenteral therapies. Collection of data on socio-demographic/clinical variables is unlikely to be helpful in predicting low/non-adherence. Alternative approaches are needed to identify individuals at risk of low/non-adherence.

INTRODUCTION

This study aims to identify individual patient reasons for stopping medications for osteoporosis, and to investigate whether this can be predicted from knowledge about socio-demographic/clinical data, or whether alternative approaches need to be used.

METHODS

The Cohort for Skeletal Health in Bristol and Avon (COSHIBA) recruited 3200 older women from South West UK, of whom a proportion were on medications for osteoporosis at baseline. Information on self-reported adherence and reasons for low/non-adherence were collected at 6-monthly intervals over a 2-year period. Data was also collected on potential predictors of and impact of low/non-adherence.

RESULTS

Two hundred thirty-three of 3200 (7.3 %) women were on medications for osteoporosis at baseline. Mean length of time on treatment prior to enrolment was 46 months. Of those on osteoporosis medications, 94.9 % were on bisphosphonates; 8.5 % reported low adherence and 21.6 % stopped their medication completely over the 2-year follow-up period. Length of time on medication at baseline did not influence rates of low/non-adherence. Reasons for low/non-adherence to bisphosphonates included side effects (53.9 %), practical reasons such as forgetting to take them (18.0 %) and beliefs about medications (20.5 %). No convincing predictors of low/non-adherence were identified.

CONCLUSIONS

Approximately 15 % of older women on oral medications for osteoporosis could be considered for alternatives including parenteral therapies. This has important implications for healthcare provision. Collection of data on socio-demographic/clinical variables is unlikely to be helpful in predicting low/non-adherence. Alternative approaches are needed to identify individuals at risk of low/non-adherence to osteoporosis medications.

Managing Osteoporosis in Patients on Long-Term Bisphosphonate Treatment: Report of a Task Force of the American Society for Bone and Mineral Research

Bisphosphonates (BPs) are the most commonly used medications for osteoporosis. This ASBMR report provides guidance on BP therapy duration with a risk-benefit perspective. Two trials provided evidence for long-term BP use. In the Fracture Intervention Trial Long-term Extension (FLEX), postmenopausal women receiving alendronate for 10 years had fewer clinical vertebral fractures than those switched to placebo after 5 years. In the HORIZON extension, women who received 6 annual infusions of zoledronic acid had fewer morphometric vertebral fractures compared with those switched to placebo after 3 years. Low hip T-score, between -2 and -2.5 in FLEX and below -2.5 in HORIZON extension, predicted a beneficial response to continued therapy. Hence, the Task Force suggests that after 5 years of oral BP or 3 years of intravenous BP, reassessment of risk should be considered. In women at high risk, for example, older women, those with a low hip T-score or high fracture risk score, those with previous major osteoporotic fracture, or who fracture on therapy, continuation of treatment for up to 10 years (oral) or 6 years (intravenous), with periodic evaluation, should be considered. The risk of atypical femoral fracture, but not osteonecrosis of the jaw, clearly increases with BP therapy duration, but such rare events are outweighed by vertebral fracture risk reduction in high-risk patients. For women not at high fracture risk after 3 to 5 years of BP treatment, a drug holiday of 2 to 3 years can be considered. The suggested approach for long-term BP use is based on limited evidence, only for vertebral fracture reduction, in mostly white postmenopausal women, and does not replace the need for clinical judgment. It may be applicable to men and patients with glucocorticoid-induced osteoporosis, with some adaptations. It is unlikely that future trials will provide data for formulating definitive recommendations. © 2015 American Society for Bone and Mineral Research.

Update on denosumab in the management of postmenopausal osteoporosis: patient preference and adherence

Patient adherence to many osteoporosis treatments, primarily bisphosphonates, is generally poor, thus leading to a significant reduction in antifracture efficacy. Patient perceptions about the necessity of the prescribed medication to treat osteoporosis and the concerns about the potential adverse effects are important and potentially modifiable determinants of adherence, in addition to other factors, such as difficult dosing regimens and high dosing frequency. Denosumab (Dmab) is a fully human monoclonal antibody against the receptor activator of nuclear factor-κB ligand (RANKL), which, through the prevention of the RANKL/RANK interaction, inhibits osteoclast-mediated bone resorption and significantly reduces the risk of vertebral, nonvertebral, and hip fractures. It is administered subcutaneously every 6 months for the treatment of postmenopausal osteoporosis. Preference and adherence to Dmab treatment were assessed in various clinical trials. Although with some limitations, available data suggest that Dmab is preferred to bisphosphonates, produces greater satisfaction than bisphosphonates, and would be preferentially chosen for long-term treatment. Moreover, patient perceptions about the necessity of Dmab treatment clearly outweigh the concerns about the injections, and positive beliefs about treatment positively influence medication-taking behavior. According to these data, Dmab may represent a reasonable alternative to bisphosphonates, particularly for osteoporotic women in whom a suboptimal or even poor adherence to oral treatments is expected.

Use of osteoporosis medications after hospitalization for hip fracture: a cross-national study

BACKGROUND

Although current osteoporosis management guidelines recommend use of pharmacologic treatment after hip fracture, the care of such patients has been suboptimal. The objective of this cross-national study was to quantify the use of and adherence to osteoporosis medication after hip fracture in 3 countries with different healthcare systems—the United States, Korea, and Spain.

METHODS

In 3 cohorts of patients aged ≥65 years hospitalized for hip fracture, we calculated the proportion receiving ≥1 osteoporosis drug after discharge. Adherence to osteoporosis treatment was measured as the proportion of days covered (PDC) during the first year after the hip fracture.

RESULTS

We identified 86,202 patients with a hip fracture: 4704 (US Medicare), 6700 (US commercial), 57,631 (Korea), and 17,167 (Spain). The mean age was 77-83 years, and 74%-78% were women. In the year before the index hip fracture, 16%-18% were taking an osteoporosis medication. Within 3 months after the index hip fracture, 11% (US Medicare), 13% (US commercial), 39% (Korea), and 25% (Spain) of patients filled ≥1 prescription for osteoporosis medication. For those who filled ≥1 prescriptions for an osteoporosis medication, the mean PDC in the year after the fracture was 0.70 (US Medicare), 0.67 (US commercial), 0.43 (Korea), and 0.66 (Spain).

CONCLUSIONS

Regardless of differences in healthcare delivery systems and medication reimbursement plans, the use of osteoporosis medications for the secondary prevention of osteoporotic fracture was low. Adherence to osteoporosis treatment was also suboptimal, with the PDC <0.70 in all 3 countries.

Persistence at 12 months with denosumab in postmenopausal women with osteoporosis: interim results from a prospective observational study

To determine persistence with subcutaneous denosumab every 6 months in women being treated for osteoporosis, we conducted a single-arm prospective, observational study in the United States and Canada. Among 935 patients enrolled, 12-month persistence was 82%, with 66 patients (7%) reporting serious adverse events and 19 patients (2%) reporting fractures.

INTRODUCTION

Increased persistence with osteoporosis therapy is associated with reduced fracture risk. Denosumab reduced fracture risk in clinical trials; persistence in community settings is undetermined. This study evaluates persistence with denosumab in community practice in the United States (US) and Canada.

METHODS

In a 24-month multicenter, prospective, single-arm, observational study, women being treated for osteoporosis were enrolled ≤4 weeks after the first subcutaneous injection of denosumab. For this 12-month prespecified interim analysis, endpoints include persistence (one injection at study entry and another within 6 months + 8 weeks), attributes associated with persistence (univariate analysis), and serious adverse events (SAEs).

RESULTS

Among 935 patients (mean age 71 years), mean baseline T-scores were -2.18 (femoral neck) and -2.00 (lumbar spine); 50% of patients had experienced osteoporotic fracture(s). At 12 months, 82 % of patients were persistent with denosumab. Baseline factors significantly (p < 0.05) associated with higher persistence included use of osteoporosis medications >5 years previously, lumbar spine T-score > -2.5, and treatment by female physicians (US). Lower persistence was associated (p < 0.05) with psychiatric diagnoses including depression, southern US residence, being divorced, separated, or widowed (US), and prior hip fracture (Canada). SAEs were reported in 66 patients (7%); no SAEs of osteonecrosis of the jaw, atypical femoral fracture, fracture healing complications, hypocalcemia, eczema, or hypersensitivity were reported. Nineteen patients (2%) reported osteoporotic fractures.

CONCLUSIONS

The 12-month persistence observed in this single-arm open-label study of US and Canadian community practice extends the evidence regarding denosumab's potential role in reducing fracture risk in postmenopausal women with osteoporosis.

Patterns and predictors of osteoporosis medication discontinuation and switching among Medicare beneficiaries

BACKGROUND

Low adherence to bisphosphonate therapy is associated with increased fracture risk. Factors associated with discontinuation of osteoporosis medications have not been studied in-depth. This study assessed medication discontinuation and switching patterns among Medicare beneficiaries who were new users of bisphosphonates and evaluated factors possibly associated with discontinuation.

METHODS

We identified patients initiating bisphosphonate treatment using a 5% random sample of Medicare beneficiaries with at least 24 months of traditional fee-for-service and part D drug coverage from 2006 through 2009. We classified medication status at the end of follow-up as: continued original bisphosphonate, discontinued without switching or restarting, restarted the same drug after a treatment gap (≥ 90 days), or switched to another anti-osteoporosis medication. We conducted logistic regression analyses to identify baseline characteristics associated with discontinuation and a case-crossover analysis to identify factors that precipitate discontinuation.

RESULTS

Of 21,452 new users followed respectively for 12 months, 44% continued their original therapy, 36% discontinued without switching or restarting, 8% restarted the same drug after a gap greater than 90 days, and 11% switched to another anti-osteoporosis medication. Factors assessed during the 12-month period before initiation were weakly associated with discontinuation. Several Factors measured during follow-up were associated with discontinuation, including more physician visits, hospitalization, having a dual-energy X-ray absorptiometry test, higher Charlson comorbidity index scores, higher out-of-pocket drug payments, and upper gastrointestinal problems. Patterns were similar for 4,738 new users followed for 30 months.

CONCLUSIONS

Among new bisphosphonates users, switching within and across drug classes and extended treatment gaps are common. Robust definitions and time-varying considerations should be considered to characterize medication discontinuation more accurately.

Comparative gastrointestinal safety of bisphosphonates in primary osteoporosis: a network meta-analysis

We completed a network meta-analysis of published papers to compare bisphosphonate gastrointestinal safety. We found that zoledronic acid had the highest chance of causing gastrointestinal adverse events. Etidronate had the highest chance of discontinuation due to an adverse event. No difference was found for serious adverse events.

INTRODUCTION

Bisphosphonates are first-line treatment for osteoporosis. Gastrointestinal (GI) adverse events (AE) are the primary reason for non-adherence. Little is known about the comparative GI safety of bisphosphonates.

PURPOSE

Leverage published clinical trial data to examine the comparative GI safety of bisphosphonates.

METHODS

We completed a systematic review of all English-language clinical trials that assessed bisphosphonate safety and/or efficacy in primary osteoporosis through to 2012. Randomized, blinded, and controlled studies were eligible. The primary outcome was any GI-related AE. Subanalyses were completed for upper GI symptoms, serious GI, nausea, esophageal-related events, and discontinuation due to AE. A Bayesian-based network meta-analysis was completed to allow for indirect comparisons. Results were reported as the probability that a specific drug had the highest number of events.

RESULTS

We identified 50 studies: 32 alendronate, 12 risedronate, 5 etidronate, and 7 zoledronic acid. Zoledronic acid had the highest probability of having the highest number of any GI AE (91%) and nausea (70%). Etidronate (70%) and zoledronic acid (28%) had the highest probability of having the greatest attrition due to AE. Etidronate had the highest probability (56%) of having the greatest number of upper GI symptoms among oral bisphosphonates.

CONCLUSION

Zoledronic acid had the highest probability of causing the greatest number of GI AE, possibly related to nausea. These results question the assumption that annual zoledronic acid will translate into better adherence. Little difference was found between alendronate and risedronate for serious AE. More research into real-world implications of the comparative safety of bisphosphonates is needed.

Commentary: measuring quality of care in osteoporosis

We know improving the quality of care in osteoporosis is an important goal. We have made some strides toward measuring quality of osteoporosis care, focusing on process measures regarding care that is provided. Unfortunately, improving care as measured by these process measures does not always yield improved outcomes. We need to hold health care providers and health care systems responsible not only for health care production but for production of health and well-being. However, there is a multiplicity of factors that will need to be considered to make this next step.

Identifying newly approved medications in Medicare claims data: a case study using tocilizumab

BACKGROUND

After U.S. licensure, parenterally administered medications are identified using non-specific drug codes. Accurately identifying these medications is critical to safety and effectiveness research. Methods to identify medications prior to assignment of specific drug codes have not been well described.

OBJECTIVES

To describe a generalized approach using non-specific drug codes to identify parenteral therapies in Medicare claims and to assess the ability of that approach to identify tocilizumab (TCZ), a new biologic agent approved in 2010.

METHODS

We used 2008-2010 Medicare data for a cohort of rheumatoid arthritis patients for algorithm development. Our algorithm classified non-specific drug codes based upon: 1) ICD9 codes; 2) unit values (i.e. dose); 3) codes for infusion/injection procedures; 4) expected versus observed total reimbursement amount and reimbursement per unit. We assessed algorithm performance by linking to an arthritis registry to examine external validity.

RESULTS

Of 472 803 claims with non-specific drug codes, 9762 claims satisfied the TCZ algorithm. 74.3% of 9762 claims were classified as TCZ by exact unit price or allowed amount, 4.4% by unique doses, 21.3% by diagnosis code and small deviation from unit price or allowed amount. The algorithm demonstrated good performance characteristics: sensitivity 94% (95% CI 80-99), specificity 100% (99-100) and PPV 97% (84-100).

CONCLUSION

Claims-based algorithms in Medicare or similar data systems can accurately identify newly approved biologics administered parenterally prior to the assignment of specific drug codes.

Bisphosphonates adherence for treatment of osteoporosis

BACKGROUND

Osteoporosis is a disease of bone metabolism in which bisphosphonates (BPS) are the most common medications used in its treatment, whose main objective is to reduce the risk of fractures. The aim of this study was to conduct a systematic review on BPs adherence for treatment of osteoporosis.

METHODS

Systematic review of articles on BPs adherence for treatment of osteoporosis, indexed on MEDLINE (via PubMed) databases, from inception of databases until January 2013. Search terms were "Adherence, Medication" (MeSH term), "Bisphosphonates" (MeSH term), and "Osteoporosis" (MeSH term).

RESULTS

Of the 78 identified studies, 27 met the eligibility criteria. Identified studies covered a wide range of aspects regarding adherence and associated factors, adherence and fracture, adherence and BPs dosage. The studies are mostly observational, conducted with women over 45 years old, showing low rates of adherence to treatment. Several factors may influence adherence: socio-economic and cultural, participation of physicians when guidance is given to the patient, the use of bone turnover markers, and use of generic drugs. The monthly dosage is associated with greater adherence compared to weekly dosage.

CONCLUSIONS

Considering the methodological differences between the studies, the results converge to show that adherence to treatment of osteoporosis with BPs is still inadequate. Further experimental studies are needed to evaluate the adherence and suggest new treatment options.