Two-year results of once-weekly administration of alendronate 70 mg for the treatment of postmenopausal osteoporosis

The effects of weekly alendronate therapy in Taiwanese males with osteoporosis

The aim of this study was to evaluate the efficacy, safety, and tolerability of weekly alendronate administration on male osteoporosis in Taiwan. This 6-month, randomized, open-label controlled trial enrolled 46 men with osteoporosis who were randomized to either 70 mg alendronate once weekly (n = 23) or control (n = 23). Bone mineral density (BMD) of lumbar spine and hip and biochemical bone turnover markers were measured; adverse events and tolerability were assessed. Subjects treated with alendronate showed a significant increase in BMD of 5.5% (vs. 2% in control group) at the lumbar spine and 2.7% (vs. 0.7%) at the femoral neck (P < 0.05) at 6 months, respectively. There were also significant decreases in serum level of bone formation marker (bone-specific alkaline phosphatase) and urinary excretion of bone resorption marker (deoxypyridinoline) at 3 and 6 months. Thus, alendronate showed anti-osteoporotic effects by increasing BMD and decreasing the concentrations of bone markers. The adverse events were mild and showed no significant difference between the two groups on safety assessments.

Review of osteoporosis pharmacotherapy for geriatric patients

BACKGROUND

Fractures are a significant problem in geriatric patients, and understanding the evidence for benefit and possible harm of osteoporosis treatments is critical to appropriate management of this patient population.

OBJECTIVE

The purpose of this article was to review the evidence and treatment considerations related to use of the approved osteoporosis treatments in the United States across the continuum of ages in the geriatric population.

METHODS

MEDLINE and the Web of Science were searched to find English-language articles published from 2000 through July 2009. Search terms included: practice guideline, osteoporosis, calcium, vitamin D, pharmacoeconomics, ethnicity, and treatment. The generic names of each of the osteoporosis treatments approved in the United States were searched to find relevant clinical trials and randomized controlled trials (RCTs). Pivotal trials that included fracture data or focused specifically on elderly patients (> or = 60 years of age) were selected. Bibliographies in the identified articles were searched for additional articles, and the prescribing information for each of the approved treatments was reviewed.

RESULTS

Many osteoporosis studies have a mean patient age >60 years, but data for older patients are limited. Subanalyses of older patient groups have found risedronate to be beneficial for vertebral fractures in patients aged 70 to 79 years (absolute risk reduction [ARR], 8.4%; P < 0.001) and teriparatide to be beneficial for both vertebral (ARR, 6.4%; P < 0.05) and new nonvertebral fragility fractures (ARR, 9.9%; P < 0.05) in women aged > or = 75 years. However, no RCTs of geriatric patients who were either nonambulatory or had multiple comorbidities were identified in the literature.

CONCLUSIONS

Evidence indicates that the osteoporosis treatments currently available in the United States are beneficial for treating osteoporosis in geriatric patients. However, data are limited for the oldest patients (> or = 80 years) and those with significant comorbidities. Because of the limited availability of data for geriatric patients with significant comorbidities, the properties of the various agents, including efficacy, tolerability, and potential contraindications, should be considered carefully for each geriatric patient.

Progress in osteoporosis and fracture prevention: focus on postmenopausal women

In the past decade, we have witnessed a revolution in osteoporosis diagnosis and therapeutics. This includes enhanced understanding of basic bone biology, recognizing the severe consequences of fractures in terms of morbidity and short-term re-fracture and mortality risk and case finding based on clinical risks, bone mineral density, new imaging approaches, and contributors to secondary osteoporosis. Medical interventions that reduce fracture risk include sufficient calcium and vitamin D together with a wide spectrum of drug therapies (with antiresorptive, anabolic, or mixed effects). Emerging therapeutic options that target molecules of bone metabolism indicate that the next decade should offer even greater promise for further improving our diagnostic and treatment approaches.

[Austrian guidance for the pharmacological treatment of osteoporosis in postmenopausal women--update 2009]

Osteoporosis is a systemic skeletal disease characterized by diminished bone mass and deterioration of bone microarchitecture, leading to increased fragility and subsequent increased fracture risk. Therapeutic measures therefore aim at reducing individual fracture risk. In Austria, the following drugs, all of which have been proven to reduce fracture risk, are currently registered for the treatment of postmenopausal osteoporosis: alendronate, risedronate, etidronate, ibandronate, raloxifene, teriparatide (1-34 PTH), 1-84 PTH, strontium ranelate and salmon calcitonin. Fluorides are still available, but their role in daily practice has become negligible. Currently, there is no evidence that a combination of two or more of these drugs could improve anti-fracture potency. However, treatment with PTH should be followed by the treatment with an anticatabolic drug such as bisphosphonates. Calcium and vitamin D constitute an important adjunct to any osteoporosis treatment.

Ibandronate: a review of its vertebral and nonvertebral antifracture efficacy

After the Ibandronate Osteoporosis Vertebral Fracture Trial in North America and Europe (BONE) study had demonstrated the strong vertebral and nonvertebral antifracture efficacy of daily and intermittent oral ibandronate, the Monthly Oral Ibandronate In Ladies (MOBILE) study gave evidence for an increased efficacy on the bone mineral density (BMD) of higher intermittent oral ibandronate doses (150 mg monthly) compared with 2.5 mg daily. The BONE study also observed nonvertebral antifracture efficacy in patients with a high risk for fractures (mean femoral neck T score of -3.0 or less). A recently published meta-analysis assessing the nonvertebral antifracture efficacy corresponding to the annual cumulative exposure (ACE) of ibandronate demonstrated a significantly better antifracture efficacy of higher compared with lower doses of ibandronate. The Dosing Intravenous Administration (DIVA) study demonstrated evidence for the high efficacy and good tolerability of intravenous ibandronate delivered by quarterly injections. This review summarizes the efficacy and tolerability data of ibandronate concerning monthly oral treatment as well as quarterly injection therapy.

Adverse effects of bisphosphonates: implications for osteoporosis management

Bisphosphonates are widely prescribed and highly effective at limiting the bone loss that occurs in many disorders characterized by increased osteoclast-mediated bone resorption, including senile osteoporosis in both men and women, glucocorticoid-associated osteoporosis, and malignancies metastatic to bone. Although they are generally well tolerated, potential adverse effects may limit bisphosphonate use in some patients. Optimal use of bisphosphonates for osteoporosis requires adequate calcium and vitamin D intake before and during therapy. The World Health Organization fracture risk assessment algorithm is currently available to determine absolute fracture risk in patients with low bone mass and is a useful tool for clinicians in identifying patients most likely to benefit from pharmacological intervention to limit fracture risk. This fracture risk estimate may facilitate shared decision making, especially when patients are wary of the rare but serious adverse effects that have recently been described for this class of drugs.

Monitoring strontium ranelate therapy in patients with osteoporosis

PURPOSE

The purpose of this study was to review the monitoring of strontium ranelate osteoporosis therapy.

METHODS

The method used in this study was comprehensive literature review with clinical perspectives.

RESULTS

Changes in bone turnover markers (BTM) or bone mineral density (BMD) have been documented in osteoporosis clinical trials. However, neither BMD nor BTM changes fully explain the observed fracture risk reduction in treated patients. If changes in BMD or BTM on therapy would be easily discernable in individual patients, and were strongly associated with fracture risk reduction, monitoring individuals would be more useful. BMD changes in patients on strontium ranelate are of a greater magnitude and hence can be easily determined in an individual patient. In addition, there exists a better correlation between fracture risk reduction and increases in BMD.

CONCLUSIONS

The strong correlation between measured BMD increases and fracture risk reduction in patients on strontium ranelate therapy will be of clinical benefit to physicians wishing to evaluate both treatment persistence and fracture risk reduction.

Bisphosphonates and osteonecrosis: potential treatment or serious complication?

They are commonly used to treat osteoporosis and other diseases that involve osteoclast-mediated bone resorption, including Paget's disease and multiple myeloma. Their use in treating osteonecrosis of the femoral head has been studied and theoretically holds promise. There are complications associated with these medications, however, including the development of osteonecrosis in the jaw.

Efficacy of bisphosphonates in reducing fracture risk in postmenopausal osteoporosis

Bisphosphonates have been available for more than a decade. Currently, 4 bisphosphonates--alendronate, risedronate, ibandronate, and zoledronic acid--are approved in the United States. Alendronate and risedronate are oral agents, ibandronate is available in oral and intravenous formulations, and zoledronic acid is an intravenous drug. This review summarizes results from pivotal clinical trials in which these bisphosphonates have been shown to reduce risk for osteoporotic fractures. Also reviewed are results of "bridging" studies designed to demonstrate the comparable efficacy of less frequent dosing regimens to increase bone mineral density and to reduce bone turnover. Compared with placebo controls, all 4 approved bisphosphonates reduce the relative risk of new vertebral fractures in women with postmenopausal osteoporosis. Alendronate, risedronate, and zoledronic acid reduce the relative risk of new nonvertebral and hip fractures. Clinical trial extensions of up to 10 years with alendronate and 7 years with risedronate have shown that efficacy is maintained during long-term treatment.

The efficacy and tolerability of once-weekly alendronate 70 mg on bone mineral density and bone turnover markers in postmenopausal Chinese women with osteoporosis

Osteoporosis has become an important health problem in postmenopausal Chinese women. Bisphosphonates currently are the preferred therapy for treating osteoporosis. However, the use of daily regimen of alendronate in women at risk for osteoporosis has been relatively low in China because of its dosing inconvenience. To determine the efficacy and tolerability of once-weekly alendronate 70 mg in Chinese, a multicenter, randomized, double blind, placebo controlled study was performed in China. Five hundred and sixty postmenopausal women (< or =85 years old) with osteoporosis were randomly assigned to receive either alendronate 70 mg or placebo once-weekly for 12 months. All women received calcium 500 mg daily and vitamin D 200 IU daily. A significant increase in lumbar spine BMD was already evident at 6 months of alendronate treatment (P < 0.001). The alendronate group showed significant increase (P < 0.001) in BMD at 12 months at both the spine and hip when compared with the placebo group (lumbar spine 4.87% vs. 0.4%, femoral neck 2.47% vs. 0.31%, trochanter 3.24% vs. 0.78%, total hip 2.56% vs. 0.28%, respectively). The percentage of women with > or =0% and > or =3% BMD increase in lumbar spine was significantly greater in women with alendronate than placebo (P < 0.001). Significant reduction in urine N-telopeptide (NTx) and serum bone-specific alkaline phosphatase were evident at 6 and 12 months, respectively, with alendronate treatment. No significant differences in the incidence of adverse experiences and upper gastrointestinal adverse experiences were seen. We conclude that once-weekly alendronate 70 mg is an effective and well-tolerated agent for the treatment of postmenopausal osteoporosis in Chinese women.

Biochemical markers of bone turnover: potential use in the investigation and management of postmenopausal osteoporosis

INTRODUCTION

The aim was to analyse data on the use of biochemical bone turnover markers (BTM) in postmenopausal osteoporosis.

METHODS

We carried out a comparative analysis of the most important papers concerning BTM in postmenopausal osteoporosis that have been published recently.

RESULTS

The BTM levels are influenced by several factors. They are moderately correlated with BMD and subsequent bone loss. Increased levels of bone resorption markers are associated with a higher risk of fracture. Changes in the BTM during the anti-osteoporotic treatment (including combination therapy) reflect the mechanisms of action of the drugs and help to establish their effective doses. Changes in the BTM during the anti-resorptive treatment are correlated with their anti-fracture efficacy.

CONCLUSION

Biological samples should be obtained in a standardised way. BTM cannot be used for prediction of the accelerated bone loss at the level of the individual. BTM help to detect postmenopausal women who are at high risk of fracture; however, adequate practical guidelines are lacking. BTM measurements taken during the anti-resorptive therapy help to identify non-compliers. They may improve adherence to the anti-resorptive therapy and the fall in the BTM levels that exceeds the predefined threshold improves patients' persistence with the treatment. There are no guidelines concerning the use of BTM in monitoring anti-osteoporotic therapy in postmenopausal women.

Bisphosphonates in the management of postmenopausal osteoporosis--optimizing efficacy in clinical practice

Nitrogen-containing bisphosphonates are potent inhibitors of osteoclastic bone resorption. With their individually proven efficacy to significantly reduce the incidence of vertebral and/or non-vertebral fractures and with their overall beneficial safety profile, alendronate, ibandronate, risedronate, and zoledronate are considered today a treatment of first choice in postmenopausal osteoporosis. However, treatment effects in an individual patient and cost-effectiveness in public health perspective are vitally dependent on the long-term patient adherence as well as on compliance and persistence. As compliance and persistence with daily oral bisphosphonates are shown to be suboptimal in many patients, leading to an increased fracture incidence in non-compliant patients, there is a need to improve overall adherence for bisphosphonate treatment in order to achieve maximum treatment effects. One option is to extend dosing intervals to weekly (alendronate, risedronate) or monthly (ibandronate) oral regimens. Less frequent oral regimens are generally preferred by majority of patients. Another alternative is intravenous, instead of oral application (ibandronate, zoledronate). Treatment acceptance could be further improved by IV bisphosphonates with their benefit of only quarterly, or even once-yearly, application. Treatment decisions should be based on anti-fracture efficacy data first. In addition, to ensure best possible patient adherence and maximum treatment benefits, physicians should consider individual patient conditions affecting compliance and persistence as well as patient preferences.

Biomarkers of bone health and osteoporosis risk

The assay features of biochemical markers of bone turnover have markedly improved in the past few years. The most sensitive and specific markers of bone formation include serum bone alkaline phosphatase, total osteocalcin (including the intact molecule and the large N-mid fragment) and the procollagen type I N-terminal propeptide assay. Among the various markers of bone resorption, measurements of the urinary excretion of N- and C-terminal cross-linked telopeptides) and of serum C-terminal cross-linked telopeptides are the most sensitive and specific. Markers of bone turnover can be used to predict the rate of bone loss in post-menopausal women and can also be used to assess the risk of fractures. In osteoporosis-treatment studies (with alendronate, risedronate, raloxifene) markers of bone turnover appear even more strongly associated with fracture risk reduction than bone mineral density (BMD). These observations support the use of markers of bone turnover as surrogates for fracture risk reduction, perhaps even more so than BMD. Bone markers can also be used to monitor the efficacy of antiresorptive therapy such as hormone-replacement therapy, raloxifene and bisphosphonates in individual patients. Furthermore, they have also proved to be helpful in monitoring the response to nutritional interventions and have the advantage over BMD in that they provide information about mechanism of effect and changes are often observed much more rapidly.

Nonvertebral fracture risk reduction with nitrogen-containing bisphosphonates

Osteoporosis is a systemic skeletal disorder characterized by low bone mass and microarchitectural deterioration of bone tissue resulting in compromised bone strength and an increased risk of fracture. There are two major fracture types: vertebral and nonvertebral. The latter include fractures involving the upper extremities, lower extremities (including hip), pelvis, and ribs. A recent review comparing the efficacy and safety of drugs approved by the US Food and Drug Administration for treatment of osteoporosis demonstrated that although all of the agents have been shown to reduce the incidence of radiographic vertebral fractures, they do not all reduce the incidence of nonvertebral fractures. This article summarizes the most currently available data relative to nonvertebral and hip fracture risk reduction for the N-containing bisphosphonates alendronate, ibandronate, risedronate, and zoledronic acid, and presents results of an analysis of comparative efficacy of these compounds using the technique of adjusted indirect comparisons.

Bisphosphonates: mechanism of action and role in clinical practice

Bisphosphonates are primary agents in the current pharmacological arsenal against osteoclast-mediated bone loss due to osteoporosis, Paget disease of bone, malignancies metastatic to bone, multiple myeloma, and hypercalcemia of malignancy. In addition to currently approved uses, bisphosphonates are commonly prescribed for prevention and treatment of a variety of other skeletal conditions, such as low bone density and osteogenesis imperfecta. However, the recent recognition that bisphosphonate use is associated with pathologic conditions including osteonecrosis of the jaw has sharpened the level of scrutiny of the current widespread use of bisphosphonate therapy. Using the key words bisphosphonate and clinical practice in a PubMed literature search from January 1, 1998, to May 1, 2008, we review current understanding of the mechanisms by which bisphosphonates exert their effects on osteoclasts, discuss the role of bisphosphonates in clinical practice, and highlight some areas of concern associated with bisphosphonate use.

Changes in bone markers after once-weekly low-dose alendronate in postmenopausal women with moderate bone loss

BACKGROUND

High bone turnover, with bone resorption exceeding bone formation, is a major mechanism of postmenopausal osteoporosis. Therefore, inhibition of bone resorption is a rational approach for the prevention of bone loss. The objective of the current study was to determine the short-term efficacy of once-weekly low-dose alendronate in the prevention of bone loss, via bone turnover markers, in early postmenopausal Korean women with moderate bone loss.

METHODS

This study involved a 12-week, randomized, double-blind clinical trial that compared the effects of placebo with alendronate 20mg once weekly. All subjects received supplemental calcium 600 mg and vitamin D 400IU daily. We recruited 63 postmenopausal women (ranging from 50 to 65 years of age) with the lowest lumbar spine bone mineral density (BMD) at least 2.0 S.D. below the mean value for young healthy adults. BMD was measured at baseline and serum alkaline phosphatase (ALP), osteocalcin, C-terminal telopeptide of type I collagen (CTX), and osteoprotegerin (OPG) were measured at baseline and 12 weeks after treatment.

RESULTS

We randomly assigned 63 women to either placebo or alencronate 20 mg once a week for 3 months. Forty-nine women continued and completed all 3 months. After 3 months, bone resorption markers were significantly decreased in the alendronate group than in the placebo group: CTX -47.2% vs. 15% (p<0.01), ALP 1.6% vs. 25.9% (p=0.01), osteocalcin -29.2% vs. -13.6 (p=0.06). Women who received alendronate showed similar results to those who received placebo with regard to adverse events.

CONCLUSION

Once-weekly low-dose alendronate may be a cost-effective and safe method of suppressing bone turnover in early postmenopausal women with moderate bone loss.

A Markov model simulation of the impact of treatment persistence in postmenopausal osteoporosis

BACKGROUND

The Markov model followed a cohort of patients over 10 years to estimate the total number of incident osteoporotic fractures by age for the overall population of women with diagnosed postmenopausal osteoporosis in France (mean age, 71.1 years +/-9.6; range, 50-96 years). The impact of clinical efficacy, persistence, and residual treatment effects data on predicted fracture risk was also estimated in the model.

RESULTS

Predicted numbers of incident fractures appeared consistent with published data. Compared with no treatment, the relative risk of fracture over 10 years was 0.831 for weekly bisphosphonate treatment with an assumed persistence rate of 51% after 1 year (absolute risk reduction = 11.4%). This relative risk decreased to 0.731 (absolute risk reduction=18.1%) if hypothetical full-treatment persistence was achieved. In terms of public health, improving persistence with bisphosphonate treatment by only 20% could have the same impact as a 20.2% increase in clinical efficacy. The benefit associated with improved persistence declines as full persistence is approached.

CONCLUSION

Improving persistence can increase treatment effectiveness. Giving greater priority to persistence interventions might have a greater impact on the health of osteoporotic women than advances in treatment efficacy.

Interventions for enhancing medication adherence

BACKGROUND

People who are prescribed self-administered medications typically take less than half the prescribed doses. Efforts to assist patients with adherence to medications might improve the benefits of prescribed medications, but also might increase their adverse effects.

OBJECTIVES

To update a review summarizing the results of randomized controlled trials (RCTs) of interventions to help patients follow prescriptions for medications for medical problems, including mental disorders but not addictions.

SEARCH STRATEGY

We updated searches of The Cochrane Library, MEDLINE, CINAHL, EMBASE, International Pharmaceutical Abstracts (IPA), PsycINFO (all via OVID) and Sociological Abstracts (via CSA) in January 2007 with no language restriction. We also reviewed bibliographies in articles on patient adherence and articles in our personal collections, and contacted authors of relevant original and review articles.

SELECTION CRITERIA

Articles were selected if they reported an unconfounded RCT of an intervention to improve adherence with prescribed medications, measuring both medication adherence and treatment outcome, with at least 80% follow-up of each group studied and, for long-term treatments, at least six months follow-up for studies with positive initial findings.

DATA COLLECTION AND ANALYSIS

Study design features, interventions and controls, and results were extracted by one review author and confirmed by at least one other review author. We extracted adherence rates and their measures of variance for all methods of measuring adherence in each study, and all outcome rates and their measures of variance for each study group, as well as levels of statistical significance for differences between study groups, consulting authors and verifying or correcting analyses as needed. The studies differed widely according to medical condition, patient population, intervention, measures of adherence, and clinical outcomes. Therefore, we did not feel that quantitative analysis was scientifically justified; rather, we conducted a qualitative analysis.

MAIN RESULTS

For short-term treatments, four of ten interventions reported in nine RCTs showed an effect on both adherence and at least one clinical outcome, while one intervention reported in one RCT significantly improved patient adherence, but did not enhance the clinical outcome. For long-term treatments, 36 of 81 interventions reported in 69 RCTs were associated with improvements in adherence, but only 25 interventions led to improvement in at least one treatment outcome. Almost all of the interventions that were effective for long-term care were complex, including combinations of more convenient care, information, reminders, self-monitoring, reinforcement, counseling, family therapy, psychological therapy, crisis intervention, manual telephone follow-up, and supportive care. Even the most effective interventions did not lead to large improvements in adherence and treatment outcomes.

AUTHORS' CONCLUSIONS

For short-term treatments several quite simple interventions increased adherence and improved patient outcomes, but the effects were inconsistent from study to study with less than half of studies showing benefits. Current methods of improving adherence for chronic health problems are mostly complex and not very effective, so that the full benefits of treatment cannot be realized. High priority should be given to fundamental and applied research concerning innovations to assist patients to follow medication prescriptions for long-term medical disorders.

Alendronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women

BACKGROUND

Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Alendronate belongs to the bisphosphonate class of drugs, which act to inhibit bone resorption by interfering with the activity of osteoclasts.

OBJECTIVES

To assess the efficacy of alendronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007.

SELECTION CRITERIA

Women receiving at least one year of alendronate, for postmenopausal osteoporosis, were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence.

DATA COLLECTION AND ANALYSIS

We undertook study selection and data abstraction in duplicate. We performed meta-analysis of fracture outcomes using relative risks and a > 15% relative change was considered clinically important. We assessed study quality through reporting of allocation concealment, blinding and withdrawals.

MAIN RESULTS

Eleven trials representing 12,068 women were included in the review. Relative (RRR) and absolute (ARR) risk reductions for the 10 mg dose were as follows. For vertebral fractures, a significant 45% RRR was found (RR 0.55, 95% CI 0.45 to 0.67). This was significant for both primary prevention, with 45% RRR (RR 0.55, 95% CI 0.38 to 0.80) and 2% ARR, and secondary prevention with 45% RRR (RR 0.55, 95% CI 0.43 to 0.69) and 6% ARR. For non-vertebral fractures, a significant 16% RRR was found (RR 0.84, 95% CI 0.74 to 0.94). This was significant for secondary prevention, with 23% RRR (RR 0.77, 95% CI 0.64 to 0.92) and 2% ARR, but not for primary prevention (RR 0.89, 95% CI 0.76 to 1.04). There was a significant 40% RRR in hip fractures (RR 0.60, 95% CI 0.40 to 0.92), but only secondary prevention was significant with 53% RRR (RR 0.47, 95% CI 0.26 to 0.85) and 1% ARR. The only significance found for wrist was in secondary prevention, with a 50% RRR (RR 0.50 95% CI 0.34 to 0.73) and 2% ARR. For adverse events, we found no statistically significant differences in any included study. However, observational data raise concerns regarding potential risk for upper gastrointestinal injury and, less commonly, osteonecrosis of the jaw.

AUTHORS' CONCLUSIONS

At 10 mg per day, both clinically important and statistically significant reductions in vertebral, non-vertebral, hip and wrist fractures were observed for secondary prevention ('gold' level evidence, www.cochranemsk.org). We found no statistically significant results for primary prevention, with the exception of vertebral fractures, for which the reduction was clinically important ('gold' level evidence).

Hip fracture protection by alendronate treatment in postmenopausal women with osteoporosis: a review of the literature

Osteoporosis most commonly affects postmenopausal women, placing them at a significant risk of fractures. In particular, hip fractures are an important cause of mortality and morbidity among postmenopausal women. Anti-resorptive therapies that produce greater decreases in bone turnover markers together with greater increases in bone mineral density (BMD) are associated with greater reductions in fracture risk, especially at sites primarily composed of cortical bone such as the hip. Thus, treatment with potent anti-resorptive drugs like alendronate is a strategy for preventing hip fractures in postmenopausal women with osteoporosis. The purpose of this paper is to discuss the efficacy of alendronate against hip fractures and the mechanism for this anti-fracture efficacy in postmenopausal women with osteoporosis. A meta-analysis of randomized controlled trials has shown that alendronate reduces the risk of hip fractures by 55% in postmenopausal women with osteoporosis. According to the analyses of the Fracture Intervention Trial, each 1 standard deviation reduction in a 1-year change in bone-specific alkaline phosphatase (BSAP) is associated with 39% fewer hip fractures in alendronate-treated postmenopausal women, and those with at least 30% reduction in BSAP have a 74% lower risk of hip fractures relative to those with less than 30%. Alendronate is effective in reducing the risk of hip fractures across a spectrum of ages. The mechanism for this anti-fracture efficacy has been clarified; alendronate strongly suppresses bone turnover and subsequently increases hip BMD, decreases cortical porosity, improves parameters of hip structure geometry (cortical thickness, cross-sectional area, section modulus, and buckling ratio), and produces more uniform mineralization (increases the mean degree of mineralization of bone) in cortical bone. A once-weekly regimen of alendronate administration provides better patient compliance and persistence with the treatment than the once-daily dosing regimen, leading to greater efficacy against hip fractures. Thus, the efficacy of alendronate against hip fractures has been confirmed in postmenopausal women with osteoporosis, especially with a once-weekly dosing regimen.

Alendronate with calcium and vitamin D supplementation is safe and effective for the treatment of decreased bone mineral density in HIV

BACKGROUND

Decreased bone mineral density (BMD) is prevalent in HIV-infected patients. Bisphosphonates are currently the mainstay of treatment for postmenopausal and male osteoporosis in HIV-uninfected individuals; however, their efficacy and safety in HIV-infected patients remains unclear.

METHODS

In this prospective, randomized, placebo-controlled multicenter trial, we studied the effectiveness of calcium and vitamin D supplementation with or without alendronate in improving BMD in HIV-infected subjects receiving stable antiretroviral therapy. Subjects with secondary causes of osteoporosis were excluded. The study was powered to detect differences of 3.5% between arms and to detect a moderate sex effect in percentage change in lumbar spine BMD. All dual-energy X-ray absorptiometry scans were analysed centrally, blinded by arm.

RESULTS

The 82 subjects enrolled were 71% men, 77% white, with a baseline median age of 48 years, CD4 cell count of 469 cells/mul, and lumbar spine t-score of less than 2.1; 91% had HIV-RNA levels less than 400 copies/ml, and 99% were taking antiretroviral drugs. Compared with calcium/vitamin D alone, alendronate plus calcium/vitamin D resulted in significant improvements in BMD at the lumbar spine, total hip, and trochanter, but not at the femoral neck, compared with baseline. There were trends towards significant increases in BMD values in the calcium/vitamin D group at the lumbar spine, total hip, and femoral neck. There were no apparent sex differences in the responses to therapy. Alendronate was well tolerated, without significant adverse events.

CONCLUSION

Once-weekly alendronate is safe and effective in the treatment of decreased BMD in HIV-infected patients.

Long-term experience with alendronate in the treatment of osteoporosis

Osteoporosis is characterised by increased bone turnover, low bone mass and impaired bone microarchitecture, leading to increased fracture risk. Effective anticatabolic therapies decrease fracture risk by reducing the rate of bone turnover, thereby maintaining bone microarchitecture and increasing bone mineral density. At present, potent oral bisphosphonates, such as alendronate (FOSAMAX; Merck & Co.), are preferred for the treatment of osteoporosis. Long-term clinical trial data demonstrate that alendronate is effective and generally well tolerated. Results from head-to-head studies and meta-analyses suggest that alendronate is more effective than certain other anticatabolic agents in the treatment of patients with osteoporosis.

Use of intravenous bisphosphonates in osteoporosis

Bisphosphonates, which are potent bone resorption inhibitors, currently are the mainstay of treatment for osteoporosis. Antifracture efficacy has been demonstrated for at least three nitrogen-containing bisphosphonates in oral formulations that are designed to be administered in weekly or monthly dosing regimens. Frequent reports of adverse events, primarily related to the upper gastrointestinal tract, and the strict dosing schedule necessary for oral bisphosphonate therapy are considered the major reasons for disappointing adherence to therapy. New intravenous formulations have been developed that allow dosing at very long intervals, thus avoiding the gastrointestinal complications associated with oral bisphosphonates and, it is hoped, improving compliance, particularly for patients who are intolerant of oral bisphosphonates or have contraindications to their use. This alternative approach holds promise for improved outcomes of osteoporosis treatment and ultimately for reduced health care costs related to caring for people with fragility fractures.

An analysis of which anti-osteoporosis therapeutic regimen would improve compliance in a population of elderly adults

OBJECTIVE

Although medications to prevent osteoporotic fractures have been proven to be effective, compliance to these therapies is generally poor. Therapeutic regimens for different anti-osteoporotic medications differ widely and it is currently unknown which regimen would be most preferred by patients.

RESEARCH DESIGN AND METHODS

We conducted a large, population-based study to discern which therapeutic attributes would be most preferable to a population representative of the age and sex distribution of patients with osteoporosis.

RESULTS

Our study sample was restricted to persons aged 55 years and over and comprised 2485 individuals (mean age of 64.5 years). The study population was predominantly female (90.3%) and two-thirds of the respondents reported current daily medication use. Nearly half (45%) of the study population preferred to take medications daily, while one in five preferred weekly therapy and 30% preferred monthly therapy (p < 0.0001 for between proportion comparisons). When given the option of choosing between three different medication regimen scenarios, those subjects not currently using anti-osteoporotic medications preferred a theoretical regimen which was daily and did not involve subsequent fasting and maintaining an upright posture.

CONCLUSIONS

Our data suggest that compliance with osteoporotic medications could be improved if patients are able to choose a therapeutic regimen best suited to their particular needs. The majority of subjects preferred a drug which was taken daily and with minimal inconvenience, rather than a weekly drug with slightly more inconvenience. Given that most physicians currently prescribe anti-osteoporotic therapy as a weekly regimen, at the time of diagnosis physicians should ascertain which regimen would be most preferable to patients prior to initiating therapy.

Drug insight: Existing and emerging therapies for osteoporosis

Osteoporosis is a major public health problem that is characterized by microarchitectural deterioration, low bone mass, and increased risk of fractures. Currently, many women and men affected with this disease are not diagnosed or treated. As osteoporosis is often clinically silent, risk-factor assessment and measurement of BMD are needed to identify those who may benefit from osteoporosis therapy. Although adequate daily intake of calcium and vitamin D, and regular weight-bearing exercise are important for skeletal health, they are not adequate treatments for individuals with osteoporosis. Therapies approved for treatment and/or prevention of osteoporosis in the United States include oral bisphosphonates (alendronate, ibandronate and risedronate), calcitonin, estrogens, teriparatide (parathyroid hormone fragment [1-34]), and raloxifene. For most patients, oral bisphosphonates are the treatment of choice, given the large-scale randomized-trial data demonstrating efficacy in fracture reduction, although bisphosphonates that reduce spine and nonspine fractures (e.g. alendronate and risedronate) are preferred. For high-risk patients (those with very low bone density, or with fractures), teriparatide therapy for 2 years should be considered. The treatment paradigm for osteoporosis will evolve further as promising new treatments progress through clinical development.

Intermittent Bisphosphonate Therapy in Postmenopausal Osteoporosis

Bisphosphonates are the most widely prescribed drugs in osteoporosis today. They have unequivocally shown their ability to reduce fracture rate at the spine (alendronic acid, risedronic acid, ibandronic acid) and at the hip (alendronic acid and risedronic acid). However, their dosage and administration procedures and the adverse reactions induced by their oral intake are responsible for low adherence. Therefore, intermittent regimens have been developed. Weekly alendronic acid and risedronic acid provide similar benefits, in terms of bone mineral density (BMD) and changes in biochemical markers, as those seen with their daily formulations. Ibandronic acid has been shown to reduce vertebral fractures when given intermittently. Ibandronic acid given orally monthly and intravenously every 2 or 3 months provides increases in BMD similar to the daily formulation. Yearly intravenous infusions of zoledronic acid are currently being evaluated for their ability to reduce fractures. If the efficacy and safety of bisphosphonates given at administration intervals longer than weekly are confirmed, this might significantly improve patient adherence and long-term outcomes of bisphosphonate treatment in postmenopausal osteoporosis.

Patient Adherence to Osteoporosis Medications

Adherence to osteoporosis medications is relatively poor. Approximately 20-30% of patients taking daily or weekly treatments may suspend their treatment within 6 to 12 months of initiating therapy. Patients with poor adherence increase their risk of osteoporotic fractures and hospitalisation. The majority of patients who discontinue therapy appear to do so because of drug-induced adverse effects. Fear of adverse effects or other health risks is another commonly cited reason for discontinuing therapy. Factors associated with medication adherence include fractures, regular exercise, female sex, fewer non-osteoporosis medications and co-morbidities, early menopause, willingness to take medications, awareness of osteoporosis status based on a diagnostic test, anti-inflammatory therapy and corticosteroid therapy. Factors associated with non-adherence include adverse effects, pain and being unsure about bone mineral density (BMD) test results. Bisphosphonates, a common class of drugs for treating osteoporosis, have specific administration requirements (e.g. fasting, remaining upright and not ingesting other medications concomitantly). Patient surveys indicate that 12-18% of patients report non-compliance with at least one administration rule. Strategies to increase adherence include reducing administration frequency to weekly or monthly, monitoring patients with bone markers and BMD testing, providing adequate instructions, practitioner feedback and support, and educational materials and sessions. Future studies are needed regarding strategies to increase adherence to osteoporosis medications.

Alendronate and vitamin D2 for prevention of hip fracture in Parkinson's disease: a randomized controlled trial

Incidence of a fracture, particularly in the hip joint, is high in elderly women with Parkinson's disease (PD), and this is due to the immobilization-induced bone resorption and vitamin D deficiency with reduced bone mineral density (BMD). The objective of this study was to address the possibility that treatment with alendronate and vitamin D2 may reduce the incidence of hip fractures in elderly women with PD. PD patients were randomly assigned to daily treatment with 5 mg alendronate (n = 144) or a placebo combined with 1,000 IU of vitamin D2 (n = 144) and followed for 2 years. Incidence of hip fractures in the two patient groups during the 2-year follow-up period was studied. At baseline, both groups of patients had low BMD with high levels of serum-ionized calcium and urinary deoxypyridinoline (D-Pyr). Hip fractures occurred in 14 patients in the placebo group and 4 in the alendronate group. The relative risk for hip fractures in the alendronate group as compared with the placebo group was 0.29 (95% CI, 0.10-0.85). The number of hip fracture per 1,000 patient-years was 14 and 49 for the alendronate and placebo groups, respectively. In the alendronate group, serum calcium and urinary D-Pyr levels decreased significantly during the follow-up period, while the levels in the placebo group were increased. BMD increased by 3.1% in the alendronate group and decreased by 2.8% in the placebo group (P < 0.01). Treatment with alendronate and vitamin D2 increases BMD in elderly women with PD and leads to the prevention of hip fractures.

Osteoporosis update: effective prevention and treatment

Osteoporosis is a public health threat to approximately 44 million individuals in the USA, or 55% of men and women over the age of 50 years. The primary goal of osteoporosis management is to prevent fracture, the most devastating consequence. Risk factors and bone mineral density can be assessed to determine appropriate action for prevention and treatment of osteoporosis. Prevention strategies include lifestyle modification, fall prevention, and adequate intake of calcium and vitamin D. Current treatment options include antiresorptive agents and anabolic agents. Adherence and cost issues play major roles in establishing optimal therapy for individual patients. New agents in development are designed to improve osteoporosis treatment and patient adherence. This review focuses on current and future prevention and treatment options for postmenopausal osteoporosis.

Drug insight: Bisphosphonates for postmenopausal osteoporosis

Bisphosphonates are potent antiresorptive agents, which have largely been used for the treatment of postmenopausal osteoporosis during the past 10 years. When embedded in bone matrix, bisphosphonates are taken up by osteoclasts engaged in bone resorption, leading--mainly by inhibition of farnesyl diphosphate synthase, a key enzyme of the mevalonate pathway--to osteoclast apoptosis. Bone resorption decreases, with consequent improvement in the mechanical properties of bone and a reduced risk of fracture. Alendronate and risedronate are oral nitrogen-containing bisphosphonates. Several randomized, placebo-controlled trials have shown the ability of these bisphosphonates to halve the risk of vertebral fracture when taken daily for 3 years. Nonvertebral fracture risk, including that at the hip, was also significantly decreased. Weekly regimens have simplified the administration of bisphosphonates and, probably, improved adherence to treatment. A significant reduction in the risk of vertebral fracture has also been demonstrated with an intermittent regimen of ibandronate, which is a new, potent, nitrogen-containing bisphosphonate. Ibandronate was recently marketed for use in an oral, once-monthly dose of 150 mg, with the goal of improving compliance. Bisphosphonates are usually well tolerated in the long term. Intravenous administration of bisphosphonates in women with osteoporosis, which is currently under investigation, might be an interesting future option for women who cannot tolerate oral regimens, and for enhancing compliance.

Alendronate sodium in the management of osteoporosis

Alendronate is one of the best and most extensively studied bisphosphonates in the treatment of osteoporosis. This review considers in detail the major pivotal study, the fracture intervention trial (FIT), upon which the use of alendronate is based and which was a landmark study in terms of design, size and clinical impact. The role of alendronate has subsequently been underscored by a range of studies extending the clinical indications for its use and consolidating the effect on reducing both vertebral and non-vertebral fracture risk. Although the emphasis of these studies has predominantly been on the management of postmenopausal osteoporosis, data is also available in primary prevention, men, and glucocorticoids-induced osteoporosis. Direct comparison between the different drugs used to treat osteoporosis with fracture end points are needed for patients and doctors to make informed choices, but the size of such studies are prohibitive. Clinical trials using surrogate markers such as bone mineral density and biochemical markers of bone turnover have been performed which provide some helpful information but the limitations of this approach need to be recognized.

Update on osteoporosis therapy

Osteoporosis is a skeletal disorder characterized by compromised bone strength that predisposes a person to increased fracture risk. Fractures are often associated with increased morbidity, higher mortality, loss of function and even psychological consequences. Pharmacotherapeutic interventions (e.g., bisphosphonates, selective estrogen receptor modulators, calcitonin, and teriparatide) in women with postmenopausal osteoporosis provide substantial reduction in fracture risk over and above risk reduction with calcium and vitamin D supplementation alone. The importance of nutritional support along with an appropriate exercise regimen, avoiding smoking and excessive alcohol use is to be emphasized along with the pharmacologic approach to osteoporosis. Despite the effectiveness of therapy with pharmacologic agents, most patients who start therapy do not remain on treatment for more than 1 year.

Once-monthly dosing: an effective step forward

To improve upon the currently suboptimal level of therapeutic adherence with bisphosphonates in postmenopausal osteoporosis, there is a need to examine less-frequently dosed regimens that offer patients greater convenience than weekly dosing. Ibandronate is a potent, nitrogen-containing bisphosphonate specifically developed for administration with long between-dose intervals. It has proven antifracture efficacy when administered orally, daily or intermittently (>2 months dose-free interval) and a safety profile comparable with placebo. A dose-ranging study evaluating a simplified once-monthly ibandronate dosing schedule confirmed the feasibility of the regimen. Significant decreases from baseline in the biochemical markers of bone turnover, serum and urinary C-telopeptide of the alpha-chain of type 1 collagen (CTX) were observed for all once-monthly doses assessed. An analysis of the area under the effect curve for these two parameters confirmed a dose-response relationship. The MOBILE study was a large (n = 1609), randomized, double-blind, non-inferiority study comparing three doses of monthly oral ibandronate (50 + 50 mg, 100 mg and 150 mg) with daily oral ibandronate (2.5 mg) in women with postmenopausal osteoporosis. Analyses have been completed at the end of 1 and 2 years of treatment. With substantial increases in lumbar spine bone mineral density (BMD; 5.3-6.6%), all of the once-monthly regimens were non-inferior, and, in addition, the 150 mg regimen was superior (P < or = 0.002) to the daily regimen. Corresponding increases in BMD were also observed at all hip sites. The greatest gains in lumbar spine, and hip BMD were consistently seen with the 150 mg regimen. Considerable reductions in serum CTX were seen with all regimens from 3 months onwards (50.0-66.4%); these reductions were maintained throughout the 2-year period (2 years: 56.1-67.7%). The safety profile of the once-monthly regimens was comparable with the daily regimen throughout the 2 years. Once-monthly ibandronate is an effective and well-tolerated treatment for patients with postmenopausal osteoporosis. Given the recently reported strong patient preference for once-monthly regimens and the impact of patient preference on therapeutic adherence, it is anticipated that once-monthly ibandronate will offer patients an alternative convenient regimen that may improve adherence over weekly bisphosphonates and should enhance outcomes.

Preventing osteoporosis-related fractures: an overview

Osteoporosis is a skeletal disorder characterized by compromised bone strength, which predisposes a person to increased risk of fracture. In the United States, 26% of women aged > or =65 years and >50% of women aged > or =85 years have osteoporosis. Over 1.5 million fractures per year are attributable to osteoporosis; these fractures result in 500,000 hospitalizations, 800,000 emergency room visits, 2.6 million physician visits, 180,000 nursing home placements, and 12 billion dollars to 18 billion dollars in direct healthcare costs each year. Fracture also results in loss of function and has a negative impact on psychological status. In recognition of the importance of bone health, the US Surgeon General has, for the first time, issued a comprehensive report on bone health and treatment. The report recommends a pyramidal approach to osteoporosis treatment that includes calcium and vitamin D supplementation, physical activity, and fall prevention as the first line in fracture prevention. The second level consists of treating secondary causes of osteoporosis; the third and top level consists of pharmacotherapy. Pharmacotherapeutic interventions (e.g., bisphosphonates, selective estrogen receptor modulators, calcitonin, and teriparatide) in women with postmenopausal osteoporosis provide substantial reduction in fracture risk over and above risk reduction with calcium and vitamin D supplementation alone. Despite the effectiveness of therapy, most patients who receive treatment do not remain on treatment for >1 year. An important approach to reducing the rate of fractures is first to target our treatments to patients at high risk for fracture and then to develop strategies to improve treatment continuation rates.

Oral ibandronate in the management of postmenopausal osteoporosis: Review of upper gastrointestinal safety

Oral daily bisphosphonates carry a potential for gastrointestinal (GI) adverse events, which has been partly addressed by introducing once-weekly regimens. Nevertheless, the need to follow inconvenient dosing instructions every week could still hinder long-term compliance and therapeutic outcome. In addition, survey data indicates that many patients would prefer a once-monthly rather than once-weekly bisphosphonate dosing regimen. Ibandronate is a potent, nitrogen-containing bisphosphonate specifically developed for less frequent administration. In a pivotal study in postmenopausal osteoporosis, oral ibandronate, administered daily or with a between-dose interval of >2 months, demonstrated robust antifracture efficacy and an overall incidence of upper GI adverse events similar to placebo, even in patients at increased risk of such events. This and other clinical studies conducted in postmenopausal women demonstrate that oral ibandronate has an excellent upper GI safety profile.

Fracture prevention in postmenopausal osteoporosis: a review of treatment options

Several treatment options are available to reduce the risk of fractures in postmenopausal women with or at risk for osteoporosis. A MEDLINE search was conducted to evaluate anti-fracture and adverse event data of osteoporosis therapies from trials in postmenopausal women. Among the anti-resorptive therapies, the bisphosphonates alendronate and risedronate have demonstrated consistent efficacy in reducing vertebral and nonvertebral fracture risk. Once-weekly alendronate and risedronate produced similar improvements in bone mineral density compared with their once-daily counterparts with similar tolerability. Daily injections of teriparatide resulted in statistically significant reductions in the risk of vertebral and nonvertebral fractures, and trials of ibandronate, raloxifene, and calcitonin nasal spray showed reductions in vertebral fracture risk. Hormone therapy has demonstrated clinical fracture risk reduction; however, safety outcomes from the Women's Health Initiative study have raised concerns regarding long-term use of these preparations. These data can guide clinical decision-making regarding the selection of an osteoporosis therapy.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to summarize adverse events data of osteoporosis therapies from trials in postmenopausal women, explain that only a few therapies have shown a consistent efficacy in reducing vertebral and nonvertebral fractures, and state that data from the Women's Health Initiative study have raised concerns regarding long-term use of estrogen-progestin therapy.

A new concept for bisphosphonate therapy: a rationale for the development of monthly oral dosing of ibandronate

Oral daily and weekly bisphosphonates represent the current mainstay of treatment for postmenopausal osteoporosis (PMO). However, the inconvenience of frequent dosing is known to negatively affect adherence to therapy in the long term. This has prompted the development of convenient oral bisphosphonate regimens that feature simple, less frequent dosing schedules. Such regimens require high potency agents, which can be given at low effective doses and that also have good tolerability. Ibandronate is a potent, nitrogen-containing bisphosphonate with proven efficacy when given intermittently to estrogen-depleted beagle dogs, rats and cynomolgus monkeys. Clinically, a pivotal prospective study has established that oral ibandronate has significant vertebral fracture efficacy in PMO, whether given daily (2.5 mg) or intermittently (20 mg every other day for 12 doses every 3 months; extended between-dose interval>2 months). Both oral regimens were well tolerated, which is noteworthy as patients with a history of gastrointestinal (GI) disturbance were not specifically excluded. As a result of these findings, a large, multinational, randomized, double-blind study (Monthly Oral iBandronate In LadiEs: MOBILE) is currently exploring the non-inferiority of once-monthly oral ibandronate (100 or 150 mg) to the oral daily ibandronate (2.5 mg) regimen with proven anti-fracture efficacy, in terms of lumbar spine bone mineral density (BMD) change. As with the trials investigating the weekly administration of other bisphosphonates, vertebral fracture efficacy will be inferred if the study demonstrates the non-inferiority of once-monthly ibandronate to the proven oral daily regimen in terms of spinal BMD change. The availability of this once-monthly ibandronate regimen is expected to offer benefits in terms of convenience (by having to follow dosing recommendations once a month vs. once daily or weekly) and potentially tolerability (by reducing the potential for upper GI irritation that can result from frequent, repeated exposure). Greater convenience and tolerability may enhance the therapy adherence and, hence, improve long-term therapeutic outcomes in PMO.

Canadian Consensus Conference on osteoporosis, 2006 update

OBJECTIVE

To provide guidelines for the health care provider on the diagnosis and clinical management of postmenopausal osteoporosis.

OUTCOMES

Strategies for identifying and evaluating high-risk individuals, the use of bone mineral density (BMD) and bone turnover markers in assessing diagnosis and response to management, and recommendations regarding nutrition, physical activity, and the selection of pharmacologic therapy to prevent and manage osteoporosis.

EVIDENCE

MEDLINE and the Cochrane database were searched for articles in English on subjects related to osteoporosis diagnosis, prevention, and management from March 2001 to April 2005. The authors critically reviewed the evidence and developed the recommendations according to the Journal of Obstetrics and Gynaecology Canada's methodology and consensus development process.

VALUES

The quality of evidence is rated using the criteria described in the report of the Canadian Task Force on the Periodic Health Examination. Recommendations for practice are ranked according to the method described in this report.

SPONSORS

The development of this consensus guideline was supported by unrestricted educational grants from Berlex Canada Inc., Lilly Canada, Merck Frosst, Novartis, Novogen, Novo Nordisk, Proctor and Gamble, Schering Canada, and Wyeth Canada.

Long-term outcome of weekly bisphosphonates

Bisphosphonates currently are the preferred therapy for treating osteoporosis. Treatment with potent bisphosphonates such as alendronate or risedronate decreases biochemical markers of bone turnover and increases bone mineral density. These changes are associated with significant reductions in vertebral and nonvertebral fracture risk. Clinical trial data with up to 10 years of followup shows these agents are effective and well tolerated for long-term periods. Daily administration is effective and generally well tolerated. However, once weekly doses are more convenient, which may enhance long-term compliance and lead to more successful outcomes. The pharmacokinetics and mechanism of action predict the short-term and long-term skeletal effects and safety profile of once-weekly doses of bisphosphonates are similar to daily doses. These predictions are supported by authors of trials of up to 2 years who report once-weekly doses are therapeutically equivalent to daily doses in terms of BMD and biochemical markers of bone remodeling. Once-weekly bisphosphonate doses have safety and tolerability profiles as good as daily doses and are comparable with the placebo.

LEVEL OF EVIDENCE

Therapeutic study, Level V (expert opinion). See the Guidelines for Authors for a complete description of the levels of evidence.

A randomized, placebo-controlled, 6-month study of once-weekly alendronate oral solution for postmenopausal osteoporosis

OBJECTIVE

This study evaluated the overall safety and tolerability of once-weekly (OW) alendronate 70 mg oral solution (OS) versus OW placebo OS.

METHODS

Postmenopausal, osteoporotic women were enrolled at 51 centers in the United States in a 6-month double-blind, randomized trial. Patients were randomized (1:1) to OW alendronate 70 mg OS or placebo OS. The primary end point was the proportion of patients reporting any upper gastrointestinal (UGI) adverse event (AE) at 6 months. Secondary end points included mean percentage change in urinary N-telopeptide of type I human collagen (NTx) and serum bone-specific alkaline phosphatase (BSAP) at 6 months.

RESULTS

Initially, 454 women were enrolled; 392 (86.3%) completed the study. The mean (SD) age was 65.2 (10) years, and the mean (SD) time since menopause was 19.1 (12) years. The proportion of patients experiencing any UGI AE was significantly higher with alendronate OS (23.7%) compared with placebo solution (15.3%), with a treatment difference of 8.3% (95% CI, 0.8%-15.8%; P = 0.024). The proportion of patients experiencing any esophageal AE was 4.0% with alendronate and 3.0% with placebo (treatment difference, 1.0% [95% CI, -2.7% to 4.8%]). In addition, 4.5% of alendronate and 8.7% of placebo patients discontinued the study due to any clinical AE, and 3.3% of alendronate and 1.8% of placebo patients discontinued due to a UGI AE (difference, 1.5% [95% CI, -1.5% to 4.4%]). Alendronate OS produced significantly greater reductions in both NTx and BSAP than placebo (differences, -47.5% and -38.7%, respectively [both, P < 0.001]).

CONCLUSIONS

In this 6-month study, patients receiving OW alendronate 70 mg OS had a higher rate of UGI AEs than placebo patients. However, rates of serious UGI AEs, discontinuations due to UGI AEs, and esophageal AEs were similar between groups. UGI AEs in the study were generally mild to moderate in severity and did not result in treatment discontinuation. In addition, OW alendronate 70 mg OS significantly reduced biochemical markers of bone turnover.

Efficacy and tolerability of once-weekly administration of 17.5 mg risedronate in Japanese patients with involutional osteoporosis: a comparison with 2.5-mg once-daily dosage regimen

In this multicenter, randomized, double-blind controlled trial, the efficacy and safety of once-weekly dosing with 17.5 mg risedronate was compared with once-daily dosing with 2.5 mg risedronate in Japanese patients with involutional osteoporosis. A total of 496 patients were randomized to receive either once-weekly (n = 249) or once-daily (n = 247) treatment. All patients were supplemented with 200 mg/day calcium. Following 48 weeks of treatment, the mean (+/-SD) percent changes, from baseline, in the bone mineral density of the lumbar spine (L2-L4 BMD) in the once-weekly and once-daily treatment groups were 5.36 +/- 4.27% and 5.87 +/- 4.47%, respectively. The difference between the groups was -0.5% (95% confidence interval: -1.35% to 0.35%), demonstrating that the effect on BMD of once-weekly treatment was not inferior to that of once-daily treatment. The time-course reductions in biochemical markers of bone resorption (urinary N- and C-telopeptide of type I collagen) and bone formation (bone-specific alkaline phosphatase) were similar for the two dosing regimens. There were no differences in the incidence of new vertebral fractures or the worsening of existing fractures between the once-weekly (2.2%) and once-daily (2.7%) dosing regimens. No significant differences were observed between the two dosing regimens in the incidence or the type of adverse events. However, 10.1% of the patients in the once-daily group withdrew due to adverse events as compared to 5.2% in the once-weekly group. Moreover, drug-related adverse events, including upper gastrointestinal disorders and abnormal changes in laboratory parameters, tended to be less in the once-weekly dosing regimen than in the once-daily dosing regimen. In conclusion, once-weekly oral dosing with 17.5 mg risedronate was well tolerated in Japanese osteoporotic patients, and showed equivalent efficacy to once-daily oral dosing with 2.5 mg risedronate. This once-weekly regimen is expected to provide a more convenient therapeutic option as an alternative to daily dosing and to enhance patient compliance in long-term therapy for osteoporosis.

The Problem of Low Levels of Vitamin D and Osteoporosis

Osteoporosis and fragility fractures are common in the elderly population and represent a large public health burden. Non-pharmacological recommendations for the management of osteoporosis include modification of lifestyle behaviours, increased weight-bearing exercise and consumption - through dietary or supplement sources - of adequate amounts of calcium and vitamin D. Although current guidelines include recommendations on calcium and vitamin D intake, patients frequently do not take sufficient amounts, even when supplements are provided free of charge. Vitamin D is essential for mineral metabolism, and low levels are associated with impaired skeletal metabolism and neuromuscular function. Nutritional sources of vitamin D are limited, and supplementation is usually necessary. A high prevalence of low vitamin D levels has been reported in a number of populations worldwide, including women being treated for osteoporosis and those with fragility fractures. At present, bisphosphonates are the most commonly prescribed pharmacological treatments for osteoporosis, and alendronic acid is the most frequently prescribed bisphosphonate. A nitrogen-containing bisphosphonate, alendronic acid has demonstrated anti-fracture efficacy at vertebral and non-vertebral skeletal sites, including the hip, in addition to long-term safety and efficacy. Weekly administration of alendronic acid takes advantage of the pharmacokinetics of the drug and osteoclast biology to optimise treatment, and may improve patient adherence. Combining alendronic acid 70mg and colecalciferol (vitamin D(3)) 2800 IU in a single, once-weekly tablet has the advantage of combining the proven efficacy of an established bisphosphonate, alendronic acid, with the amount of vitamin D currently recommended for osteoporosis management.

The use of unequal randomisation ratios in clinical trials: a review

OBJECTIVE

To examine reasons given for the use of unequal randomisation in randomised controlled trials (RCTs).

MAIN MEASURES

Setting of the trial; intervention being tested; randomisation ratio; sample size calculation; reason given for randomisation.

METHODS

Review of trials using unequal randomisation. DATABASES AND SOURCES: Cochrane library, Medline, Pub Med and Science Citation Index.

RESULTS

A total of 65 trials were identified; 56 were two-armed trials and nine trials had more than two arms. Of the two-arm trials, 50 trials recruited patients in favour of the experimental group. Various reasons for the use of unequal randomisation were given. Six studies stated that they used unequal randomisation to reduce the cost of the trial, with one screening trial limited by the availability of the intervention. Other reasons for using unequal allocation were: avoiding loss of power from drop-out or cross-over, ethics and the gaining of additional information on the treatment. Thirty seven trials papers (57%) did not state why they had used unequal randomisation and only 14 trials (22%) appeared to have taken the unequal randomisation into account in their sample size calculation.

CONCLUSION

Although unequal randomisation offers a number of advantages to trials the method is rarely used and is especially under-utilised to reduce trial costs. Unequal randomisation should be considered more in trial design especially where there are large differences between treatment costs.