An endoscopic comparison of the effects of alendronate and risedronate on upper gastrointestinal mucosae

Incident peptic ulcers and concomitant treatment of direct oral anticoagulants and oral bisphosphonates-a real-world cohort study

Oral bisphosphonates and direct oral anticoagulants are related to upper gastrointestinal ulcers. The present study investigated whether concomitant use of these drugs increase the risk of upper gastrointestinal ulcers and report no increased risk of upper gastrointestinal ulcers compared to the use of either drug alone, when individuals with previous upper gastrointestinal ulcers are excluded.

INTRODUCTION

This study examines whether concomitant use of oral bisphosphonates (oBP) and direct oral anticoagulants (DOAC) increases the risk of peptic ulcers more than any drug alone.

METHODS

A population-based cohort study was performed. We sampled a cohort of oBP and DOAC users from a sample of 2,622,742 individuals, consisting of diabetes patients and age- and gender-matched controls, obtained from the Danish National Patient Register. The exposures were concomitant use of oBP and DOAC and single use of DOAC and single use of oBP. The primary endpoint was the first incident peptic ulcer. Information on exposure and outcome were collected from national registries. The period of observation was from 01.01.2008 until 31.12.2018. Unadjusted and adjusted Cox regressions were performed.

RESULTS

8077 individuals received concomitant treatment with DOAC and oBP; 96,451 individuals used DOAC and no oBP; and 118,675 used oBP and no DOAC. The mean duration of follow-up was 1.9 years for concomitant users, 2.5 years for DOAC users, and 4.5 years for oBP users. A total of 4742 individuals with incident peptic ulcers were collected. We observed an increased risk of incident ulcer in users of DOAC and oBP compared to single DOAC treatment in the adjusted analysis (HR = 1.23, 95% CI: 1.03; 1.48). However, the effects were abolished when excluding individuals with a previous ulcer. We observed an increased risk of incident ulcer in users of DOAC and oBP compared to users of oBP in the adjusted model (HR = 1.34, 95% CI: 1.11; 1.63).

CONCLUSION

Based on our results, concomitant use of oBP and DOAC is associated with a slight increase in the risk of peptic ulcers compared to either drug alone. The prescribing physician should weigh the slight increased risk of ulcer in concomitant users of oBP and DOAC with beneficial reductions in stroke and fractures.

Oral Treatment With Bisphosphonates of Osteoporosis Does Not Increase the Risk of Severe Gastrointestinal Side Effects: A Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Bisphosphonates (BPs) are first-line therapy for osteoporosis. Adherence is usually low in chronic, asymptomatic diseases, but gastrointestinal (GI) side-effects can also contribute to low adherence in BP therapy and may necessitate a review by a gastroenterologist with or without gastroscopy.

AIMS

Our meta-analysis aims to determine the risk of severe GI adverse events due to oral BP therapy in osteoporotic patients.

METHODS

A systematic search was conducted in three databases up to September 2020 for randomized controlled trials (RCTs) detailing GI adverse events in adults with osteoporosis on BP compared to placebo. Risk ratios (RRs) with 95% confidence intervals (CI) were calculated for non-severe and severe adverse events indicating endoscopic procedure with the random-effects model. Statistical heterogeneity was assessed using chi² and I² statistics.

RESULTS

Forty-two RCTs with 39,047 patients with 9,999 non-severe and 1,503 severe GI adverse events were included. The incidence of non-severe and severe adverse events ranged between 0.3-54.9 and 0-10.3%, respectively. There was no difference between BP and control groups in terms of the risk of non-severe or severe side effects: RR=1.05 (CI: 0.98-1.12), I² = 48.1%, and RR=1.01 (CI: 0.92-1.12), I² = 0.0%, respectively. Subgroup analysis of the most commonly used BP, once-weekly alendronate 70 mg, revealed an association between bisphosphonates and the risk of non-severe GI adverse events, RR=1.16 (CI: 1.00-1.36), I² = 40.7%, while the risk of severe GI side effects was not increased in this subgroup, RR=1.20 (CI: 0.83-1.74), I² = 0.0%.

CONCLUSION

Our results show that bisphosphonates do not increase the risk of severe GI adverse events. However, the marked variability of the screening for side effects in the included studies, and the fact that in most of the studies GI diseases were exclusion criteria limits the strenght of evidence of our results. The conclusions drawn from the meta-analysis are therefore restricted to selected populations, and the results must be interpreted with caution.

Symptoms and Upper Gastrointestinal Mucosal Injury Associated with Bisphosphonate Therapy

Objective The incidence of osteoporosis is increasing with the rapid aging of the Japanese population. Bisphosphonates are first-line agents used for the treatment of osteoporosis, but they can cause upper gastrointestinal mucosal injury. This study investigated symptoms and upper gastrointestinal mucosal injury associated with oral bisphosphonates. Methods Symptoms were evaluated using the F-scale questionnaire, and esophageal mucosal injury and gastroduodenal ulceration were assessed by endoscopy. Patients were stratified by the type of bisphosphonate (alendronate, risedronate, or minodronate), treatment schedule (once weekly or every four weeks), and the concomitant use of other medications [antithrombotic agents, nonsteroidal anti-inflammatory drugs (NSAIDs), or acid suppressants]. Patients The subjects included 221 patients treated with oral bisphosphonates for at least one month. Results The median F-scale total score was 4 (0-34), reflux score was 2 (0-20), and the mean dyspepsia score was 2 (0-16). Endoscopy showed esophageal mucosal injury of Grade A or worse (Los Angeles classification) in 22/221 patients (10.0%) and gastroduodenal ulcers in 9 patients (4.1%). The dyspepsia score in patients who took minodronate every four weeks was significantly lower (p<0.05) in comparison to patients who took other bisphosphonates. The dyspepsia score was significantly higher (p<0.05) and mucosal injury was significantly more frequent in patients who also used antithrombotic agents and NSAIDs. Conclusion Symptoms and upper gastrointestinal mucosal damage were not necessarily frequent or severe in patients treated with bisphosphonates. However, the concomitant use of bisphosphonates with antithrombotic agents and NSAIDs increased both symptoms and mucosal injury. The symptoms were milder in patients using minodronate once monthly.

Treatment with once-weekly alendronate oral jelly compared with once-weekly alendronate oral tablet for Japanese patients with primary osteoporosis: An open-label, prospective, observational study

BACKGROUND AND AIMS

Clinical data regarding alendronate jelly are limited. We compared the efficacy and safety of once-weekly alendronate oral jelly with once-weekly alendronate tablet formulations in the context of primary osteoporosis.

METHODS

In this 6-month, open-label, prospective, observational study, Japanese patients aged ≥60 years with primary osteoporosis were included from 14 primary care centres in Japan. The effects of once-weekly alendronate oral jelly and tablet formulations on bone mineral density (BMD), bone turnover markers, and quality of life related to gastrointestinal symptoms were assessed at baseline and 6 months. Treatment was allocated by patient preference. This potentially confounding factor was adjusted for statistically.

RESULTS

In total, 170 patients were enrolled (jelly, n = 97; tablet, n = 73). Mean percent changes in radius, lumbar spine, femoral neck, and hip BMD were similar in both treatment groups at 6 months. Both formulations decreased tartrate-resistant acid phosphatase 5b (TRACP-5b) and procollagen 1 N-terminal peptide (P1NP) between baseline and 6 months (by about 50% and 60%, respectively); no significant differences in mean changes were noted in these markers between groups. At 6 months, no significant differences were noted in visual analogue scale or EuroQOL five-dimension questionnaire scores between groups. The jelly group had significantly lower scores than the tablet group in the Izumo scale domains of heartburn (-0.81, P = 0.0040), epigastralgia (-0.94, P = 0.0003), and epigastric fullness (-0.49, P = 0.044). During treatment, more patients discontinued for upper gastrointestinal symptoms in the tablet group (n = 4) than the jelly group (n = 1).

CONCLUSIONS

Once-weekly alendronate oral jelly 35 mg may be a suitable alternative therapeutic agent for primary osteoporosis in Japan.

Biodegradable intranasal nanoparticulate drug delivery system of risedronate sodium for osteoporosis

CONTEXT

Osteoporosis (OP) is the most common metabolic bone disease predominantly found in elderly people. It is associated with reduced bone mineral density, results in a higher probability of fractures, especially of the hip, vertebrae, and distal radius. Worldwide prevalence of OP is considered a serious public health concern.

OBJECTIVE

The purpose of the present work was to develop and evaluate polymeric nanoparticles (NPs) of risedronate sodium (RIS) for the treatment of OP using intranasal (IN) route in order to reduce peripheral toxic effects.

MATERIALS AND METHODS

Polymeric NPs of RIS were prepared by nanoprecipitation methods. Formulations were developed and evaluated in context to in vitro drug release, ex vivo permeation, in vivo study, and biochemical studies.

RESULTS AND DISCUSSIONS

The particles size, entrapment efficiency (EE) (%), and loading capacity (LC) (%) of optimized formulations were found to be 127.84 ± 6.33 nm, 52.65 ± 5.21, and 10.57 ± 1.48, respectively. Release kinetics showed diffusion-controlled, Fickian release pattern. Ex vivo permeation study showed RIS from PLGA-NPs permeated significantly (p < 0.05) through nasal mucosa. In vivo study showed a marked difference in micro-structure (trabeculae) in bone internal environment. Biochemical estimation of treated group and RIS PLGA indicated a significant recovery (p < 0.01) as compared with the toxic group.

CONCLUSION

Polymeric NPs of RIS were prepared successfully using biodegradable polymer (PLGA). Intranasal delivery showed a good result in in vivo study. Thus PLGA-NPs have great potential for delivering the RIS for the treatment and prevention of OP after clinical evaluation in near future.

The hydrogen sulfide donor, Lawesson's reagent, prevents alendronate-induced gastric damage in rats

Our objective was to investigate the protective effect of Lawesson's reagent, an H2S donor, against alendronate (ALD)-induced gastric damage in rats. Rats were pretreated with saline or Lawesson's reagent (3, 9, or 27 µmol/kg, po) once daily for 4 days. After 30 min, gastric damage was induced by ALD (30 mg/kg) administration by gavage. On the last day of treatment, the animals were killed 4 h after ALD administration. Gastric lesions were measured using a computer planimetry program, and gastric corpus pieces were assayed for malondialdehyde (MDA), glutathione (GSH), proinflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL)-1β], and myeloperoxidase (MPO). Other groups were pretreated with glibenclamide (5 mg/kg, ip) or with glibenclamide (5 mg/kg, ip)+diazoxide (3 mg/kg, ip). After 1 h, 27 µmol/kg Lawesson's reagent was administered. After 30 min, 30 mg/kg ALD was administered. ALD caused gastric damage (63.35 ± 9.8 mm(2)); increased levels of TNF-α, IL-1β, and MDA (2311 ± 302.3 pg/mL, 901.9 ± 106.2 pg/mL, 121.1 ± 4.3 nmol/g, respectively); increased MPO activity (26.1 ± 3.8 U/mg); and reduced GSH levels (180.3 ± 21.9 µg/g). ALD also increased cystathionine-γ-lyase immunoreactivity in the gastric mucosa. Pretreatment with Lawesson's reagent (27 µmol/kg) attenuated ALD-mediated gastric damage (15.77 ± 5.3 mm(2)); reduced TNF-α, IL-1β, and MDA formation (1502 ± 150.2 pg/mL, 632.3 ± 43.4 pg/mL, 78.4 ± 7.6 nmol/g, respectively); lowered MPO activity (11.7 ± 2.8 U/mg); and increased the level of GSH in the gastric tissue (397.9 ± 40.2 µg/g). Glibenclamide alone reversed the gastric protective effect of Lawesson's reagent. However, glibenclamide plus diazoxide did not alter the effects of Lawesson's reagent. Our results suggest that Lawesson's reagent plays a protective role against ALD-induced gastric damage through mechanisms that depend at least in part on activation of ATP-sensitive potassium (KATP) channels.

Gastric and esophagus events before and during treatment of osteoporosis

Prior studies have indicated an excess risk of gastroduodenal ulcers and esophagus perforations with the use of bisphosphonates. However, little is known about the contribution of comorbid conditions and concomitant drug use on this risk. We studied the risk of esophagus and gastric events in patients on a wide range of drugs against osteoporosis both before and after initiation of these drugs. We studied a nationwide register-based cohort from Denmark with all users of drugs against osteoporosis between 1996 and 2006 (n = 103,562) as cases and three age- and sex-matched controls from the general population (n = 310,683). In a crude analysis, most drugs were already associated with an increased risk of esophagitis, esophageal ulcerations, or esophageal perforations or gastroduodenal ulcers before initiation of the drugs. Upon adjustment, this excess risk disappeared for most drugs except parathyroid hormone and its analogues, etidronate and clodronate. Only for etidronate, alendronate, and raloxifene were sufficient data present for events after initiation of the drugs, and for these, an increased risk was present for all events except gastroduodenal ulcers with raloxifene. Several drugs against osteoporosis are associated with an increased risk of esophagitis, esophageal ulcers, esophageal perforation, and gastroduodenal ulcers. However, the increase was already present before initiation of the drug for several types of drugs against osteoporosis. This points at an effect of the underlying condition being treated or comorbid conditions and drugs being provided in patients with osteoporosis, such as nonsteroidal anti-inflammatory drugs and corticosteroids.

[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.

Clodronic acid formulations available in Europe and their use in osteoporosis: a review

Clodronic acid (Cl(2)-MBP [dichloromethylene bisphosphonic acid], clodronate) is a halogenated non-nitrogen-containing bisphosphonate with antiresorptive efficacy in a variety of diseases associated with excessive bone resorption. The drug is believed to inhibit bone resorption through induction of osteoclast apoptosis, but appears also to possess anti-inflammatory and analgesic properties that contrast with the acute-phase and inflammatory effects seen with nitrogen-containing bisphosphonates. Clodronic acid has been shown to be effective in the maintenance or improvement of bone mineral density when given orally, intramuscularly or intravenously in patients with osteoporosis. Use of the drug is also associated with reductions in fracture risk. The intramuscular formulation, which is given at a dose of 100 mg weekly or biweekly, is at least as effective as daily oral therapy and appears more effective than intermittent intravenous treatment. Intramuscular clodronic acid in particular has also been associated with improvements in back pain. The drug is well tolerated, with no deleterious effects on bone mineralization, and use of parenteral therapy eliminates the risk of gastrointestinal adverse effects that may be seen in patients receiving bisphosphonate therapy.

Bisphosphonate increases risk of gastroduodenal ulcer in rheumatoid arthritis patients on long-term nonsteroidal antiinflammatory drug therapy

BACKGROUND

Rheumatoid arthritis (RA) patients are at increased risk of peptic ulcers (PU) induced by nonsteroidal antiinflammatory drugs (NSAIDs). However, the impact of potential drug interactions on the development of PU has yet to be determined in a daily clinical setting. The aim was to estimate the clinical important interactions for PU presented by comedication in Japanese RA outpatients on long-term NSAID treatment.

METHODS

This retrospective cohort study enrolled 196 consecutive RA outpatients on NSAID medication for at least 3 months. Potential risk factors for endoscopic PU were analyzed in RA outpatients on longterm NSAID treatment.

RESULTS

PU incidence was 31% with bisphosphonate co-therapy and 17% without the co-therapy. PU incidence was only 5% in subjects with proton pump inhibitors (PPI) or prostaglandin E1 analogues (PG) co-therapy, 14% with histamine-H(2) receptor antagonists(H2RA) co-therapy, and 27% without anti-ulcer agents. In multivariate logistic regression analysis, bisphosphonate co-therapy remained a significant risk factor for PU (OR, 2.29; 95% CI, 1.09-4.81). Other risk factors for ulcer development were advanced age (greater than 60 years) and smoking (OR, 2.58; 95% CI, 1.03-6.49 and OR, 2.71; 95% CI, 1.13-5.53, respectively.) Factors that significantly reduced the incidence of PU were H2RA or PPI/PG cotherapies (OR, 0.29; 95% CI, 0.12-0.68.).

CONCLUSIONS

Bisphosphonate co-therapy as well as advanced age and smoking was found to be a significant risk factor in PU, while co-therapies of standard-dose H2RA or PPI/PG proved effective in preventing PU in Japanese RA patients on long-term NSAID treatment.

New developments surrounding the safety of bisphosphonates

PURPOSE OF REVIEW

Several new issues have been linked with the use of bisphosphonates in recent years. This has complicated the use of this important class of agents. This article reviews data surrounding these issues and discusses the impact on patient care.

RECENT FINDINGS

Gastrointestinal toxicity has been a classic side effect of oral bisphosphonates. Newer issues such as osteonecrosis of the jaw have clearly been associated with bisphosphonate use, and adjustments to clinical practice need to be made to prevent and address this new complication. Atrial fibrillation has also been associated with bisphosphonates in recent years, but the literature is variable, and the connection is not clear. Limiting musculoskeletal pain is a rare side effect of bisphosphonates, but public awareness has been heightened by a recent Food and Drug Administration alert. Severe suppression of bone turnover is the most recent potential complication, and an increasing literature has made this a much more clinically relevant issue.

SUMMARY

With all the public exposure regarding the various concerns associated with bisphosphonates, clinicians need to be keenly aware of the details surrounding these issues. Patients need to be presented with a digestible synopsis, such that risks and benefits can be evaluated, an informed decision regarding treatment can be made, and possible complications can be prevented or discovered early.

Valid treatment options for osteoporosis and osteopenia in HIV-infected persons

OBJECTIVE

To review clinical data on bone ossification agents that may be considered for use in the treatment of osteoporosis and osteopenia in HIV-infected patients.

DATA SOURCES

A literature search was performed using MEDLINE (1950-January 2008), EMBASE, PubMed, and abstracts from major HIV conferences (February 2001-October 2007). These searches were limited to human data published in English and used the key words bisphosphonates, calcitonin, raloxifene, teriparatide, HAART, osteopenia, osteoporosis, and HIV/AIDS. Additional articles were retrieved from citations of selected references.

STUDY SELECTION AND DATA EXTRACTION

Relevant information on the pharmacology, pharmacokinetics, safety, and efficacy of available treatment with hormonal and nonhormonal agents was selected. Greater emphasis was placed on randomized clinical trials than on retrospective studies.

DATA SYNTHESIS

Osteoporosis in HIV-infected persons is at least as prevalent as in postmenopausal women, yet this population is not listed in primary care guidelines as one that should be considered for screening. In addition to bisphosphonates, calcitonin, raloxifene, and teriparatide are used to treat bone disorders. Three clinical trials to date have evaluated the use of a bisphosphonate in HIV-infected persons. The trials showed a marked increase in bone mineral density in patients taking alendronate versus those in the control groups (with/without calcium, exercise, and/or vitamin D in 1 or both arms). Dosing restrictions complicate the use of these agents; diet, exercise, and calcium supplementation remain the foremost recommended strategies to prevent bone loss. The use of estrogen, testosterone, calcitonin, and teriparatide is less studied in HIV-positive patients, but may be considered in select cases. There are some investigational drugs and agents not available in the US; however, there are not enough data to support their use.

CONCLUSIONS

Alendronate appears to be a promising treatment option for HIV-infected patients with osteoporosis and osteopenia. Further research is required to determine the safety and efficacy of other available drugs. Until additional information is provided, and with available knowledge on the metabolism profiles of antiretroviral and bone ossification agents, alendronate appears to be the preferred agent to use in this population.

Alendronate for the treatment of osteoporosis in men

BACKGROUND

Men have higher rates of osteoporosis and suffer fragility fractures more often than previously believed. Fracture-related morbidity and mortality in men is substantially higher than in women.

OBJECTIVE

To investigate alendronate for treating osteoporosis in men.

METHODS

Search limited to 'men' and 'English'; keywords were 'osteoporosis' or 'bone density' or 'fracture' and 'alendronate'.

RESULTS/CONCLUSIONS

Alendronate is an amino-bisphosphonate with proved efficacy for increasing bone mineral density in men with idiopathic or secondary osteoporosis and has demonstrated an ability to prevent vertebral fractures in men with low bone mass. There are trends for alendronate to decrease the risk of non-vertebral fracture, but larger trials are needed to conclusively establish this benefit. Alendronate is a well-tolerated and comparatively safe drug with an attractive once-a-week dosing regimen.

Safety considerations with bisphosphonates for the treatment of osteoporosis

Bisphosphonates are the most commonly prescribed medications for the treatment of osteoporosis. Although evidence supports a good safety profile for these agents, numerous tolerability issues have been associated with their use. This review provides an overview of the safety issues associated with the nitrogen-containing class of bisphosphonates and discusses the potential effect of these issues on adherence. The review specifically considers upper gastrointestinal (UGI) adverse events (AEs), renal toxicity, influenza-like illness, osteonecrosis of the jaw and evidence on how to treat or prevent these events. In clinical trials, UGI AEs, including severe events such as oesophageal ulcer, oesophagitis and erosive oesophagitis, have been reported at similar frequencies in placebo- and active-treatment arms. However, postmarketing studies have highlighted UGI AEs as a concern. These studies show that a significant portion of patients are less compliant with administration instructions outside strict clinical trial supervision, and when oral bisphosphonates are not administered as directed, patients are more likely to experience UGI AEs. Some clinical trials with oral bisphosphonates have suggested that a decrease in the frequency of administration may lead to improvement in gastrointestinal tolerability. In the authors' experience, the issue of UGI tolerability can be minimised by explaining to the patient and/or caregiver the importance of following administration instructions. Intravenous (IV) bisphosphonates have been recently approved for use in osteoporosis, offering an alternative regimen for patients with osteoporosis. Earlier generation IV bisphosphonates (e.g. etidronate) have been associated with acute renal failure. Alternatively, late-generation IV bisphosphonates (i.e. ibandronate) have shown a better safety profile in relation to renal toxicity. Influenza-like illness, often referred to as an acute-phase reaction, covers symptoms such as fatigue, fever, chills, myalgia and arthralgia. These symptoms are transitory and self-limiting and usually do not recur after subsequent drug administration. Symptoms of influenza-like illness have been associated with both IV and oral bisphosphonates. Osteonecrosis of the jaw has also been associated with IV bisphosphonate treatment, particularly in patients treated with high doses. A small number of patients with cancer and osteoporosis using oral bisphosphonates have also reported this AE. As osteonecrosis of the jaw is difficult to treat and is often associated with dental procedures and poor oral hygiene, preventive measures seem to be the best management option for patients taking bisphosphonates.Overall, the safety and tolerability profile of the nitrogen-containing bisphosphonates is good, and long-term treatment does not appear to carry a risk of serious AEs. By encouraging adherence to administration instructions physicians can minimise certain complications, such as UGI intolerability. By being aware of other potential safety issues, such as renal impairment, influenza-like illness and osteonecrosis of the jaw, physicians can detect these AEs early in the course of treatment.

Risedronate reduces postoperative bone resorption after cementless total hip arthroplasty

Forty-three patients who had undergone cementless THA were randomly assigned to receive no osteoactive drug or oral risedronate for 6 months. Postoperative decrease of BMD in the risedronate group was significantly lower than that seen in the control group in zones 1, 2, 3, 6, and 7.

INTRODUCTION

Proximal bone resorption around the femoral stem often has been observed after total hip arthroplasty (THA), could lead to late stem loosening. We previously reported the efficacy of etidronate on periprosthetic bone resorption after cementless THA. Recently risedronate is suggested to be effective for the prevention and treatment of for osteoporosis. The purpose of the present study was to evaluate the effects of risedronate on periprosthetic bone loss after cementless THA.

METHODS

Forty-three patients who had undergone cementless THA were randomly assigned to receive no osteoactive drug (21 patients) or oral risedronate 2.5 mg/day (22 patients) for 6 months. Three patients were eliminated from the risedronate group because of dyspepsia. Periprosthetic bone mineral density (BMD) in seven regions of interest based on the zones of Gruen et al. was measured with dual energy X-ray absorptiometry at 3 weeks and 6 months postoperatively.

RESULTS

At 6 months after surgery, postoperative decrease of BMD in the risedronate group was significantly lower than that seen in the control group in zones 1, 2, 3, 6, and 7 (p < 0.05, p < 0.01, p < 0.01, p < 0.05, and p < 0.05, respectively).

CONCLUSION

These outcomes suggested that risedronate might reduce the periprosthetic bone resorption after cementless THA.

Postmenopausal osteoporosis: an update on current and future therapeutic options

Recent advances in osteoporosis have dramatically changed the management and treatment of this disease. This article reviews the safety and efficacy of US FDA-approved drugs for prevention and treatment of postmenopausal osteoporosis, as well as studies on combination, sequential or intermittent use of these agents. A review of promising agents for osteoporosis therapy is provided.

Postmenopausal osteoporosis. What have we learned since the introduction of bisphosphonates?

Over the past 12 years bisphosphonates have become a mainstay of treatment for postmenopausal osteoporosis. As a class, bisphosphonates significantly suppress bone turnover and increase BMD at the lumbar spine and other site through their direct inhibitory effects on osteoclasts. Alendronate and risedronate reduce the incidence of clinical vertebral and non-vertebral fractures. Etidronate and both oral and intravenous ibandronate reduce the incidence of clinical vertebral fractures, but data from primary analyses for reduction in non-vertebral fractures are currently less robust. Intravenous administration of zoledronate is under late-stage investigation for use in postmenopausal osteoporosis. Combinations of alendronate with estrogen or raloxifene provide a greater reduction in bone turnover markers and greater increases in BMD, but fracture risk reduction has not been determined. Overall, bisphosphonates are well tolerated. The most common side effects of oral bisphosphonates are upper gastrointestinal symptoms. Newer safety concerns about the use of bisphosphonates include osteonecrosis of the jaw and oversuppression of bone turnover. The optimal duration of bisphosphonate treatment has not been clearly established.

Risedronate for prevention and treatment of osteoporosis in postmenopausal women

Risedronate sodium is an N-containing bisphosphonate that has been approved for the prevention and treatment of osteoporosis in postmenopausal women. An increase in the rate of bone remodelling is a regular feature of oestrogen withdrawal during the menopausal transition, but excessive remodelling leads to bone fragility. Risedronate and similar compounds reduce the rate of bone remodelling by suppressing the action of osteoclasts. The antifracture efficacy of risedronate is impressive. In large clinical trials of postmenopausal women with osteoporosis-related fracture(s) at entry, the risk of incident vertebral and non-vertebral fractures was reduced by approximately 40%. In older women at risk for hip fracture, incident hip fractures were also reduced by approximately 40%. Antifracture efficacy develops within the first 6 months, and treatment has been followed for as long as 5 years without deleterious effects on bone. We await reports of experience with risedronate in 'real-world' cases of greater complexity (i.e., in patients with co-morbidities and medications that would have excluded them from published clinical trials).

Drug injury in the upper gastrointestinal tract: effects of alendronate

Osteoporosis is a disease characterized by an increase in bone resorption and a decline in bone density, which leads to increased susceptibility to bone fractures. Long-term therapy is needed to increase bone mineral density and maintain bone strength. Safe and well-tolerated medical therapies are required for long-term maintenance. Alendronate, an oral bisphosphonate, has been used for treatment of osteoporosis since the mid 1990s; however, recent studies have suggested alendronate can have significant gastrointestinal side effects. Most data suggest that the risk of these effects is low and not significantly higher than with placebo but there are limited reports that suggest otherwise, in both clinical trials and animal studies. Alendronate continues to remain an important mainstay of osteoporosis therapy.

Prescription-event monitoring study on 13,164 patients prescribed risedronate in primary care in England

Risedronate sodium is indicated in postmenopausal women for the prevention and treatment of osteoporosis and for the treatment of Paget's disease. Our aim was to evaluate the safety of risedronate in a large cohort of patients prescribed risedronate by general practitioners (GPs) in England, soon after it was marketed. An observational cohort study was conducted using the technique of prescription-event monitoring (PEM). Exposure data were obtained from dispensed National Health Service prescriptions issued between September 2000 and June 2002. Outcome data were collected by sending questionnaires to prescribing GPs requesting them to report any events that had occurred since starting risedronate, demographic details, indication, start and stop dates, reasons for stopping, suspected adverse drug reactions (ADRs) and causes of death. Event rates calculated as incidence densities (IDs) separately, for Paget's disease group and all other patients (osteoporosis group) were ranked and the difference between IDs in month 1 and months 2-6 calculated. The osteoporosis cohort comprised 13,180 patients (10,934 [83.0%] female); median ages for female and male patients were 73 and 69 years, respectively. The most frequently reported event in the first month of treatment was dyspepsia, being also amongst the most frequently reported reasons for stopping risedronate and suspected ADR. Adverse events assessed as possibly or probably related to risedronate included, six of facial edema and one each of Stevens-Johnson syndrome, swollen tongue, palpitation and episcleritis. Risedronate was fairly well tolerated. Adverse events affecting skin, eye, cardiovascular and immunological systems were identified. Prescribing doctors should be aware of these and monitor their patients accordingly.

Biological properties and mechanism of action of ibandronate: application to the treatment of osteoporosis

Bisphosphonates, with their proven efficacy and safety, are the most commonly prescribed treatment for women with postmenopausal osteoporosis; however, optimal efficacy is often not achieved due to poor patient adherence to medication. Poor adherence leads to an increased risk of fracture, which itself results in morbidity, elevated healthcare costs and potentially, mortality. Although weekly rather than daily dosing of bisphosphonates has improved adherence, there remains a significant problem, and dosing less frequently than weekly has been suggested as a possible means for further improving adherence. Ibandronate is a new bisphosphonate that has a specific structure and set of characteristics that enable less frequent dosing than currently available bisphosphonates. This review provides details of the general structural features of all bisphosphonates and how these are understood to contribute to their functions in osteoporosis treatment. From this, the unique structure of ibandronate is described, along with how this translates into the high antiresorptive potency, favorable bone-binding, persistence in bone, and good tolerability that permits less frequent dosing. Finally, the clinical evidence for ibandronate is briefly presented, demonstrating the viability of less frequent dosing, with its potential benefits for patient convenience and adherence to therapy.

Alendronate improves bone mineral density in primary biliary cirrhosis: a randomized placebo-controlled trial

Bone loss is a well-recognized complication of primary biliary cirrhosis (PBC). Although it has been suggested that alendronate might improve bone mineral density (BMD) in PBC, no randomized placebo-controlled trial has been conducted. The primary aim of this study was to compare the effects of alendronate versus placebo on BMD and biochemical measurements of bone turnover in patients with PBC-associated bone loss. We conducted a double-blinded, randomized, placebo-controlled trial. Patients with a PBC and BMD t score of less than -1.5 were randomized to receive 70 mg per week of alendronate or placebo over 1 year. BMD of the lumbar spine and proximal femur were measured at entry and at 1 year. Changes from baseline in BMD and biochemical measurements of bone turnover were assessed. Thirty-four patients were enrolled. Seventeen patients were randomized to each arm. After 1 year, a significantly larger improvement (P = .005) in spine BMD was observed in the alendronate group (0.09 +/- 0.03 g/cm2 SD from baseline) compared with the placebo group (-0.003 +/- 0.02 g/cm2 SD from baseline). A larger improvement (P = .046) was also observed in the femoral BMD of alendronate patients versus placebo. BMD changes were independent of concomitant estrogen therapy. The rate of adverse effects was similar in both groups. In conclusion, in patients with PBC-related bone loss, alendronate significantly improves BMD compared with placebo. Although in this study oral alendronate appears to be well tolerated in patients with PBC, larger studies are needed to formally evaluate safety.

Optimizing Administration of Bisphosphonates in Women with Postmenopausal Osteoporosis

Bisphosphonates have been approved in the US as oral medication for the treatment of osteoporosis for about 10 years. Efficacy data exists for fracture reduction for the commonly used oral bisphosphonates but not for intravenous formulations. Based on the mechanism of action that appears to allow for longer intervals between doses, it has been possible to extend the treatment choices from the original more demanding daily oral dose to an array of options including oral weekly and more recently monthly treatment (so-called cyclical therapy) and intravenous treatment with various administration regimens. The possibility of treatment with an annual (or less frequent) intravenous administration with zoledronic acid exists. Compliance, adverse effects, and efficacy vary with each administration regimen.

Benefit-Risk Assessment of Raloxifene in Postmenopausal Osteoporosis

Raloxifene, a nonsteroidal benzothiophene, is a second-generation selective estrogen receptor modulator (SERM) that is an antiresorptive agent. Raloxifene is a non-hormonal agent that binds to the estrogen receptor and results in estrogen agonist effects on bone and the cardiovascular system and estrogen antagonist effects on endometrial and breast tissue. Raloxifene has diverse pharmacodynamic properties due to its differential interactions with the estrogen receptor and tissue selectivity. Raloxifene was the first SERM to be approved for the prevention and treatment of postmenopausal osteoporosis. In this review, we conducted a systematic search of the literature for trials that evaluated the following outcomes: bone density, fractures, quality of life, cardiovascular outcomes, safety and adverse events. Raloxifene at the approved dosage of 60 mg/day increased lumbar spine bone density by 2.5% relative to control after 2 years of therapy. A large fracture prevention trial confirmed that treatment with raloxifene 60 mg/day for 3 years decreased the relative risk of incident vertebral fractures by 30-50% in women with prevalent fractures or osteoporosis. Extraskeletal effects of raloxifene include a reduction in total cholesterol and low density lipoprotein cholesterol levels. Assessment of the safety profile revealed that raloxifene was not associated with endometrial hyperplasia and that there was a 72% reduction in the incidence of invasive breast cancer in raloxifene-treated postmenopausal women with osteoporosis. Adverse events associated with raloxifene included an increase in the absolute risk of venous thromboembolism and an increase in the risk of hot flashes and leg cramps. In comparison to other osteoporosis therapies, raloxifene has a lesser impact on bone mineral density, a similar effect on the occurrence of vertebral fractures, but no effect on the frequency of non-vertebral fractures. Raloxifene can be recommended for the prevention of vertebral fractures in women with osteopenia/osteoporosis who are not at high risk of non-vertebral fractures and who do not have a past history of venous thromboembolism.

Prevention of postmenopausal osteoporosis with pharmacological therapy: practice and possibilities

Postmenopausal osteoporosis (PMO) is a common disease that will become more prevalent in the future, with costly implications for public health. Prevention of the disease and its consequences, namely fractures, is therefore, important for both the individual and society. This review discusses: the goals of PMO prevention; the identification of women at risk, including the use of bone mineral density and bone turnover markers; the relevance in the prevention setting of various current guidelines for PMO management; recent data on therapeutic options for the treatment and prevention of PMO, in particular bisphosphonates, hormone replacement therapy and several other new pharmacological agents. It concludes that it is crucial for PMO prevention to start before disease onset and that, in the light of recent evidence, the existing guidelines need updating if they are to continue to be relevant.

Rational use of oral bisphosphonates for the treatment of osteoporosis

Osteoporosis has become a major public health concern worldwide. Significant morbidity, mortality, and health expenditures are associated with osteoporotic fractures. Evidence from randomized controlled trials and meta- analyses supports the efficacy and safety of oral bisphosphonates as first-line pharmacologic agents for the prevention and treatment of osteoporosis. This article reviews the evidence demonstrating the beneficial effects of etidronate, alendronate, and risedronate on improving bone mass and preventing fractures in individuals with or at risk for osteoporosis. Issues surrounding dosing intervals and optimal duration of therapy are also discussed. We conclude that the nitrogen-containing bisphosphonates alendronate and risedronate are safe and efficacious agents in preventing and treating osteoporosis. They are superior to cyclical etidronate in improving appendicular bone mass, and in reducing future risk for nonvertebral fractures. Once-weekly dosing options with alendronate and risedronate are effective and reduce serious adverse drug effects, and therefore, are welcome additions to our therapeutic armamentarium.

The Impact of Fragility Fracture on Health-Related Quality of Life

Both general and specific health status instruments can be utilised in evaluating health-related quality of life (HR-QOL) deficits resulting from osteoporotic fractures. Osteoporotic hip, vertebral and wrist fractures significantly decrease HR-QOL in most HR-QOL domains investigated. The presence of multiple vertebral fractures leads to larger decrements in HR-QOL. More research needs to be completed with these HR-QOL tools to better assess the true burden of osteoporotic fractures, particularly in the case of hip fractures, as the burden is surely being underestimated without recognition of HR-QOL. Only when the burden of fragility fractures is understood, inclusive of HR-QOL, will the value of proven antifracture prevention and treatment therapies be appreciated. Information collected by HR-QOL instruments may provide new insight as to how to improve quality of life for patients with fractures and how to properly allocate healthcare spending.

Medication-induced oesophageal disorders

Medication-induced oesophageal distress and injury have become increasingly common conditions. First, smooth muscle relaxants may worsen or produce symptoms of pre-existing gastro-oesophageal reflux disease; notable examples include certain calcium antagonists (nifedipine), nitrates, sildenafil, nicotine, theophylline, and substances with antimuscarinic potential. Second, drugs with local toxicity may produce de novo damage including inflammation, strictures, ulcers, and bleeding. Notorious examples are alendronate, certain antibiotics including tetracyclines and clindamycin, all NSAIDs/aspirin, quinidine, potassium chloride, and ferrous sulfate. Cyclooxygenase-2 inhibitors may be devoid of such toxicity, but may damage the mucosa by interfering with regenerative cell proliferation. The galenic formulation can modulate the risk of oesophageal injury. For this reason, medicines containing the same potentially toxic ingredient may be less exchangeable than commonly thought. Diagnostic gold standard is endoscopy. The best treatment is removal of the offending drug and supportive care. Prevention requires a re-appraisal of the drug's indication and adherence to guidelines of optimal drug intake including ingestion in an upright position and swallowing with enough fluid. The clinical relevance of drug-induced oesophageal injury and the feasibility of therapeutic alternatives are individually addressed.

Bisphosphonate treatment of osteoporosis

Bisphosphonates represent the agents of choice for most patients with osteoporosis. They are the best studied of all agents for the prevention of bone loss and reduction in fractures. They increase BMD, primarily at the lumbar spine, but also at the proximal femur. In patients who have established osteoporosis, bisphosphonates reduce the risk of vertebral fractures, and are the only agents in prospective trials to reduce the risk of hip fractures and other nonvertebral fractures. Bisphosphonates reduce the risk of fracture quickly. The risk of radiographic vertebral deformities is reduced after 1 year of treatment with risedronate [68]. The risk of clinical vertebral fractures is reduced after 1 year of treatment with alendronate [69] and just 6 months' treatment with risedronate [157]. The antifracture effect of risedronate has been shown to continue through 5 years of treatment [158]. Alendronate and risedronate are approved by the FDA for prevention of bone loss in recently menopausal women, for treatment of postmenopausal osteoporosis, and for prevention (risedronate) and treatment (alendronate and risedronate) of glucocorticoid-induced osteoporosis. Alendronate is also approved for treatment of osteoporosis in men. Other bisphosphonates (etidronate for oral use, pamidronate and zoledronate for intravenous infusion) are also available and can be used off label for patients who cannot tolerate approved agents. Although bisphosphonates combined with estrogen or raloxifene produce greater gains in bone mass compared with single-agent treatment, the use of two antiresorptive agents in combination cannot be recommended because the benefit on fracture risk has not been demonstrated and because of increased cost and side effects.

Bisphosphonate mechanism of action

The nitrogen-containing bisphosphonates (N-BPs), alendronate and risedronate, are the only pharmacologic agents shown to prevent spine and nonvertebral fractures associated with postmenopausal and glucocorticoid-induced osteoporosis. At the tissue level, this is achieved through osteoclast inhibition, which leads to reduced bone turnover, increased bone mass, and improved mineralization. The molecular targets of bisphosphonates (BPs) have recently been identified. This review will discuss the mechanism of action of BPs, focusing on alendronate and risedronate, which are the two agents most widely studied. They act on the cholesterol biosynthesis pathway enzyme, farnesyl diphosphate synthase. By inhibiting this enzyme in the osteoclast, they interfere with geranylgeranylation (attachment of the lipid to regulatory proteins), which causes osteoclast inactivation. This mechanism is responsible for N-BP suppression of osteoclastic bone resorption and reduction of bone turnover, which leads to fracture prevention.

Comparison of change in bone resorption and bone mineral density with once-weekly alendronate and daily risedronate: a randomised, placebo-controlled study

OBJECTIVE

To compare the effects of alendronate (ALN) 70 mg once weekly (OW) and risedronate (RIS) 5 mg daily between-meal dosing on biochemical markers of bone turnover and bone mineral density (BMD) in postmenopausal women with osteoporosis.

RESEARCH DESIGN AND METHODS

This was a 3-month, randomised, double-blind, placebo-controlled study with a double-blind extension to 12 months. The study enrolled 549 postmenopausal women (ALN 219, RIS 222 and placebo (PBO) 108) who were > or =60 years of age at outpatient centres.

MAIN OUTCOME MEASURES

The primary endpoint was reduction in urine N-telopeptides of type 1 collagen (NTx) corrected for creatinine level at 3 months. Secondary parameters included change in BMD at the spine and hip at 6 and 12 months, NTx at 1, 6 and 12 months, and serum bone-specific alkaline phosphatase (BSAP) at 1, 3, 6 and 12 months. Adverse experiences (AEs) were recorded throughout the study for an assessment of treatment safety profiles and tolerability.

RESULTS

Over 3 months, ALN produced a significantly greater mean reduction in urine NTx than did RIS (-52% vs -32%, p < 0.001), which was maintained at 12 months. ALN produced a significantly greater mean BMD increase than did RIS at 6 months, and it was maintained at 12 months at the lumbar spine (4.8% vs 2.8%, p < 0.001) and total hip (2.7% vs 0.9%, p < 0.001), as well as at the trochanter and femoral neck. Significant reductions in BSAP with ALN compared to RIS were maintained over the 12 months of treatment. Study size did not allow for meaningful assessment of differences in fracture rates. Tolerability was generally similar between ALN, RIS and PBO, and the incidence of upper GI AEs causing discontinuation and oesophageal AEs was similar in the ALN and RIS groups.

CONCLUSION

In this study, ALN 70 mg OW produced a 50% greater reduction in bone resorption as measured by urine NTx and significantly greater increases in lumbar spine and hip BMD than did RIS 5 mg daily. The treatments had similar safety profiles and were generally well-tolerated. Additional studies are needed comparing OW ALN with OW RIS, which became available after the commencement of the present study.

Long-term tolerability of the bisphosphonates in postmenopausal osteoporosis: a comparative review

Osteoporosis in postmenopausal women is a growing health concern for society. Bisphosphonates have become the mainstay of prevention and treatment with the mounting evidence of their efficacy over the past two decades. This review article examines the use of the etidronate, alendronate and risedronate. The pivotal trials are reviewed for long-term tolerability, evidence regarding histological safety and gastrointestinal tolerance. Etidronate, alendronate and risedronate have also been examined in meta-analyses, which reviewed methodologically sound trials. Length of treatment, adverse events and medication discontinuation and patients lost to follow-up were evaluated. Etidronate trials and the recent meta-analysis support the safe clinical use of cyclical etidronate with no signs of osteomalacia or other skeletal pathology over 2 to 3 years. In addition to increased bone mineral density (BMD) and vertebral fracture risk reduction, patients tolerated cyclical etidronate well up to 4 years in randomised studies. Non-randomised data has shown safety up to 7 years with clinical and bone biopsy data. Alendronate studies demonstrated similar overall adverse event rates, study discontinuation rates and loss to follow-up rates between placebo and treatment arms, in addition to consistent improvements in BMD, vertebral and non-vertebral fracture risk reductions over 3 to 4 years. Histological safety has been demonstrated up to 3 years. Longer-term therapy in non-randomised trials up to 7 years showed similar clinical safety between alendronate and placebo. Risedronate trials and the meta-analysis also showed similar adverse event profiles between placebo and treatment arms, as well as improvements in BMD, vertebral and non-vertebral fracture risk reductions up to 3 years. Rates of discontinuation due to gastrointestinal events were similar between groups. Histological safety has also been demonstrated for risedronate up to 3 years. Each of these bisphosphonates have been shown to have comparable safety with placebo up to 3 to 4 years, with the most rigourous trials carried out for alendronate and risedronate. Long-term comparative studies are awaited.

Oral bisphosphonates and upper gastrointestinal tract problems: what is the evidence?

OBJECTIVE

To review and evaluate the evidence regarding possible associations of bisphosphonate use with upper gastrointestinal (GI) tract adverse events (AEs).

METHODS

We reviewed and summarized published information and abstracts regarding upper GI tract safety and tolerability of bisphosphonates, including laboratory and animal studies, epidemiological (observational) studies, endoscopy studies, and randomized controlled trials (RCTs). The evidence was summarized by using the principles of evidence-based medicine, giving the greatest credence to high-quality RCTs.

RESULTS

Clinical reports of esophagitis associated with bisphosphonate use appear to have declined in frequency once the importance of proper administration was explained to physicians after early reports of complications. Conflicting results have been reported in endoscopy studies; some reported no significant increase in upper GI tract lesions, whereas others reported a higher incidence of gastric (but not esophageal) lesions among patients taking oral bisphosphonates. Endoscopy studies that reported differences were of short duration (2 weeks) and were not of double-blind design. Results from large RCTs involving thousands of participants detected no increase in upper GI tract AEs among individuals treated with bisphosphonates. Other studies of patients who discontinued taking bisphosphonates and were randomized to blinded re-treatment with either a bisphosphonate or placebo show that most patients (>85%) were able to continue treatment, with no difference in AEs between the bisphosphonate and placebo groups.

CONCLUSIONS

The highest level of evidence, RCTs, suggests little or no increase in risk of upper GI tract problems if bisphosphonates are administered properly. Upper GI tract symptoms are common among patients with osteoporosis. The evidence suggests that many upper GI tract AEs reported during therapy with bisphosphonates may reflect a high background incidence of upper GI tract complaints and an increased sensitivity to detection rather than a causal relationship to therapy.

[Ulcerative esophagitis associated with the use of alendronate sodium: histopathological and endoscopic features]

BACKGROUND

Drug-induced or "pill-induced" esophagitis may be secondary to the prolonged contact of the drug with the esophageal mucosa or secondary to the drug ability to alter the local conditions. The alendronate sodium, a bone resorption inhibitor used in the treatment and prevention of osteoporosis, has been cited, recently, as one of the causes of adverse upper gastrointestinal tract injury.

AIM

To describe the clinical, endoscopic and histopathological features of patients with ulcerative esophagitis associated with alendronate sodium.

PATIENTS

Four women and one man with osteoporosis were treated with alendronate sodium and submitted to endoscopy followed esophageal biopsy.

RESULTS

The age range of the patients was from 64 to 84 years old. The patients showed dyspeptic symptoms after taking alendronate sodium during a period of 2-12 months. At endoscopic evaluation, the mucosa was friable, with erosion and/or ulceration covered by fibrin in the distal esophagus. The pathological examination of the esophageal biopsies revealed ulcerative esophagitis characterized by necrofibrinpurulent material, granulation tissue, and yellow refractile polarizable crystal. The patients' symptoms resolved after stopping alendronate sodium use.

CONCLUSIONS

The esophagus injuries associated with alendronate sodium are not frequent and seem to be associated with the incorrect use of medication. The endoscopists and pathologists should be alert to the possibility of alendronate sodium therapy in cases of diagnosis of ulcerative esophagitis in ancient patients, particularly in women. The recognition of this condition would improve the patient care.

The gastrointestinal tolerability and safety of oral bisphosphonates

Oral bisphosphonates are effective for osteoporosis and other hyperresorptive bone disorders. Although well-tolerated in efficacy trials, some oral aminobisphosphonates have been associated with upper gastrointestinal intolerance and injury in postmarketing experience. Clinical trials often underestimate the rate of adverse events in clinical practice, and ethics prohibit direct evaluation of toxicity in high-risk patients. Accordingly, animal models and endoscopy studies of oral bisphosphonates provide valuable insight. It is unclear whether variation in ulcerogenic potential reflects differences in dosing, formulation or chemical structure. Furthermore, the clinical relevance of endoscopic lesions is uncertain. Ongoing postmarketing review will determine whether differences in endoscopic damage predict tolerability and safety in clinical practice. However, physicians and patients should consider risk factors for oesophageal injury when initiating therapy.

Alendronate: an update of its use in osteoporosis

Alendronate (alendronic acid) is a nitrogen-containing bisphosphonate which binds to bone surfaces and inhibits bone resorption by osteoclasts. Oral alendronate 5 or 10 mg/day produces sustained increases in bone mineral density (BMD) in postmenopausal women with or without osteoporosis, in men with primary osteoporosis and in both men and women with or without osteoporosis receiving systemic corticosteroid therapy. Histomorphometric analyses have found that alendronate does not appear to impair bone quality. Alendronate reduced the risk of radiographic vertebral fracture, clinical vertebral fracture or hip fracture by 47 to 56% in postmenopausal women who had > or = 1 existing vertebral fracture and in those with no existing vertebral fractures but who had osteoporosis. In a number of comparative trials in postmenopausal women with osteoporosis, alendronate 10 mg/day was found to be more effective at inducing sustained increases in BMD than intranasal calcitonin, and at least as effective as conjugated estrogens and raloxifene. Alendronate 70 mg administered once weekly and 35 mg twice weekly are as effective at increasing BMD as 10 mg/day in this patient group. In clinical trials, alendronate was generally well tolerated when taken as recommended. Adverse events tended to be transient and associated with the upper GI tract, most commonly including abdominal pain, nausea, dyspepsia, acid regurgitation and musculoskeletal pain. No statistically significant differences between alendronate 10 mg/day and placebo have been found in the incidence of upper GI adverse events in large clinical trials. However, postmarketing surveillance reported a low incidence of adverse events related to the oesophagus. Specific instructions aimed at reducing the risk of upper GI adverse events have been provided by the manufacturer.

CONCLUSIONS

Alendronate is effective and generally well tolerated in the treatment of women or men with primary (including postmenopausal) or corticosteroid-induced osteoporosis and in the prevention of osteoporosis in postmenopausal women. The drug has been associated with upper GI tract adverse events, although the extent to which alendronate is responsible for these events has not been clearly established. Alendronate should be considered a treatment of choice in postmenopausal women with osteoporosis. Alendronate is also a suitable treatment option for primary osteoporosis in men and for corticosteroid-induced osteoporosis in both men and women.

The upper GI safety and tolerability of oral alendronate at a dose of 70 milligrams once weekly: a placebo-controlled endoscopy study

OBJECTIVE

Alendronate (10 mg daily) has been shown in long term clinical trials to be an effective treatment for postmenopausal osteoporosis. A weekly dosing regimen of alendronate is preferred by both patients and physicians, as it has the potential to provide greater convenience and enhance compliance. In a 1-yr clinical trial, alendronate (70 mg once weekly) was equally efficacious and at least as well tolerated as the 10-mg daily dose in the treatment of postmenopausal osteoporosis, despite the higher unit dosage required. We conducted a randomized, double blind, placebo- and active-controlled endoscopy study to confirm the results of this clinical trial. We hypothesized that mean endoscopic gastric erosion scores would be similar in subjects receiving alendronate (70 mg once weekly) and those receiving a placebo.

METHODS

Two hundred seventy-seven subjects (90 men and 187 women) were randomized to one of three treatment groups: 1) alendronate (70 mg once weekly) for 10 wk (N = 126), 2) placebo (once weekly) for 10 wk (N = 126), or 3) placebo (once weekly) for 10 wk followed by aspirin (650 mg q.i.d.) for the last week as the positive control (N = 25). Esophagogastroduodenoscopy was performed 5 to 7 days after the last dose of alendronate or matching placebo.

RESULTS

The mean gastric erosion scores (Lanza scale) were similar in subjects given alendronate (70 mg once weekly) and those given a placebo (0.32 vs 0.35, respectively; 95% CI for difference = -0.22-0.16, p = 0.75), whereas scores in both groups were significantly lower than in those given aspirin (3.09; p < 0.001). Endoscopic gastroduodenal ulcers occurred in no alendronate (0%), two placebo (1.7%), and five aspirin (23.8%) subjects. The mean erosion scores in the esophagus and duodenum of alendronate and placebo subjects were also similar. The incidences of upper GI symptoms were similar in the alendronate and placebo subjects and did not suggest a relationship with endoscopic lesions.

CONCLUSIONS

Alendronate (70 mg once weekly) was not associated with any increase in endoscopic lesions in the upper GI tract relative to a placebo.

Gastrointestinal Adverse Effects of Bisphosphonates

The bisphosphonate class of drugs are now utilized extensively in the treatment of patients with osteoporosis and Paget's disease. Gastrointestinal (GI) adverse effects, especially those associated with esophageal injury, have been of increasing concern to clinicians. Studies in humans and animals have shown that the mucosal erosion and ulceration seen with bisphosphonates is a result of direct contact with these agents. Numerous endoscopic studies in healthy volunteers and postmenopausal women have also demonstrated the potential of bisphosphonates to cause stomach and duodenal ulcers. However, serious GI adverse events have not been noted in several large efficacy trials. Esophageal injury has for the most part been avoided by appropriate administration instructions, and gastroduodenal injury appears to be an acute phenomenon not associated with significant complications, except in certain high-risk situations, for example in the presence of existing distal esophageal disease or motility disorders, or with concurrent use of nonsteroidal anti-inflammatory drugs or anticoagulants. From the standpoint of GI safety, the bisphosphonates are well tolerated and not associated with serious adverse events.

Review of risedronate in the treatment of osteoporosis

Risedronate (Actonel, Procter & Gamble and Aventis) is a novel, orally administered pyridinyl bisphosphonate. Preclinical studies have shown that risedronate is a potent inhibitor of osteoclasts. Risedronate inhibited bone resorption and increased bone density in the spine and hip. Prospective, randomised, placebo-controlled trials (RCTs) in patients with postmenopausal osteoporosis (PMO) have demonstrated that risedronate decreased the risk of vertebral fractures by up to 49% and of non-vertebral fractures by up to 39% over 3 years in postmenopausal women with one or more prevalent vertebral fractures. This reduction of the risk for vertebral fractures was significant from the first year of treatment (risk reduction up to 65%). Risedronate was the first bisphosphonate to be studied in a large RCT with prevention of hip fracture as the primary end point. In this study, risedronate reduced the risk of hip fracture by 40% in elderly women with low hip bone density and one clinical risk factor for hip fracture and by 60% in women with low bone density and a prevalent vertebral fracture at baseline. Risedronate was also effective in the prevention and treatment of bone loss in glucocorticoid-induced osteoporosis (GIO), with a positive effect on vertebral fractures within the first year. Risedronate was well-tolerated with a safety profile comparable to placebo in all clinical studies. Patients with a previous or current history of upper GI illness or who were taking NSAIDs or aspirin were not excluded from these studies. Importantly, the upper GI safety profile of risedronate was shown to be similar to that of placebo in endoscopic studies. There was no evidence of acute-phase reactions or primary mineralisation defects. The most appropriate dose of risedronate was 5 mg/day.

Risedronate

Risedronate is a novel orally administered pyridinyl bisphosphonate indicated for the prevention or treatment of postmenopausal and glucocorticoid-induced osteoporosis and Paget's disease. The drug reduces bone turnover and decreases resorption chiefly through osteoclastic effects, with no undesirable effects on cortical porosity or thickness or on cancellous bone volume. Four randomised, double-blind trials have been carried out in 4873 patients with postmenopausal osteoporosis. In 2 of these studies, the primary end-point of vertebral fracture incidence was reduced by risedronate 5mg once daily by up to 65 and 49% relative to placebo after 1 and 3 years, respectively. Across all 4 trials, risedronate improved lumbar spine, femoral neck and femoral trochanter bone mineral density (BMD) statistically significantly relative to placebo. The drug also prevented bone loss in a study in 383 women with recent menopause, and reduced the risk of hip fracture in elderly women with confirmed osteoporosis in a trial involving a total of 9331 patients. Risedronate 5 mg/day plus estrogen has been shown to be superior to estrogen alone in a 12-month double-blind study in 524 women with at least 1-year's history of menopause. Two randomised, double-blind and placebo-controlled 12-month studies in a total of 518 patients have shown risedronate 5 mg/day to prevent or reverse bone loss in patients receiving glucocorticoid therapy. Risedronate 30 mg/day was associated with statistically significant reductions in mean serum levels of alkaline phosphatase (ALP) in noncomparative studies in patients with Paget's disease. ALP normalisation rates ranged from 53.8 to 65% across two 84-day treatment cycles in 2 of these trials in 180 patients. In a randomised, double-blind study in 123 patients, risedronate 30 mg/day for 2 months evoked significantly greater serum ALP responses than etidronate 400 mg/day for 6 months. The overall tolerability profile of risedronate was similar to that of placebo in clinical studies, with no evidence of acute-phase reactions or mineralisation defects, or excess incidence of upper GI lesions, in patients receiving the drug.

CONCLUSIONS

Risedronate is an effective and well tolerated novel bisphosphonate that is suitable for first-line therapy in Paget's disease. The rapid and sustained reductions in vertebral fracture incidence and BMD changes seen in patients with postmenopausal and glucocorticoid-induced osteoporosis indicate the drug to be a valuable treatment option with first-line potential, particularly in patients for whom hormonal therapy is inappropriate. The effects of the drug on hip fracture incidence in elderly women with confirmed osteoporosis point to a particular role in older patients, or those with more advanced disease.