Placebo-controlled Trials (placebo-controlled + trials)

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Distribution within Medical Sciences


Selected Abstracts


Placebo-controlled trials in Western phytotherapy and conventional medicine mostly of poor quality

FOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 4 2007
Article first published online: 14 JUN 2010
[source]


Multidimensional effects of sertraline in social anxiety disorder

DEPRESSION AND ANXIETY, Issue 1 2006
Kathryn M. Connor M.D.
Abstract Clinical trials of social anxiety disorder (SAD) have largely focused on the effect of treatment on symptoms of fear and avoidance, while neglecting the third clinically relevant dimension, physiological arousal. Data were combined from two previously reported placebo-controlled trials of sertraline in the treatment of moderate-to-severe generalized SAD. Efficacy was evaluated using the Brief Social Phobia Scale (BSPS). Three hundred forty-six subjects were randomized to 12,13 weeks of treatment with sertraline and 273 subjects to placebo. Following treatment, significant improvement was noted in favor of sertraline on the full BSPS (P<.001), as well as on each of the individual BSPS subscales: fear (P=.001); avoidance (P<.0001); and physiological arousal (P<.0001). Of the physiological symptoms assessed, the treatment advantage with sertraline was maintained for blushing (P<.003) and palpitations (P<.03), but not for trembling and sweating. These results confirm the efficacy of treatment with a selective serotonin reuptake inhibitor (SSRI), sertraline, across the spectrum of fear, avoidance, and physiological arousal in generalized SAD (GSAD). Among common physiological symptoms in this population, blushing and palpitations appear more treatment responsive than trembling and sweating to acute treatment with sertraline. Depression and Anxiety 23:6,10, 2006. © 2005 Wiley-Liss, Inc. [source]


Carisbamate as adjunctive treatment of partial onset seizures in adults in two randomized, placebo-controlled trials

EPILEPSIA, Issue 3 2010
Michael R. Sperling
Summary Purpose:, To assess the efficacy, safety, and tolerability of the investigational drug carisbamate as adjunctive treatment for partial-onset seizures (POS). Methods:, Two identical, randomized, placebo-controlled, double-blind studies were conducted in adults with POS uncontrolled for ,1 year. Therapy-refractory epilepsy patients (,16 years) remained on stable doses of prescribed antiepileptic drugs (,2) for an 8-week prospective baseline phase and were then randomized (1:1:1) to carisbamate 200 mg/day, carisbamate 400 mg/day, or placebo, for a 12-week double-blind phase. Primary efficacy end points were percent reduction in seizure frequency and responder rate (patients with ,50% reduction in POS frequency) during the double-blind phase compared with the prospective baseline phase. Results:, Of the 565 patients randomized in study 1, 93% completed the study; of the 562 randomized in study 2, 94% completed the study. Patient characteristics were similar across both studies and treatment arms: mean age, 35 years (study 1, range 16,75 years) and 36 years (study 2, range 16,74 years); approximately 50% were men. Treatment with carisbamate 400 mg/day resulted in significant improvement (p < 0.01) in both efficacy measures compared with placebo in study 1 but not in study 2. Carisbamate 200 mg/day did not differ statistically from placebo in either study. Among the most common treatment-emergent adverse events (,5% in any group), those with an incidence exceeding placebo (,3%) were dizziness (400 mg/day group) and somnolence. Conclusions:, Carisbamate 400 mg/day was effective in patients with refractory partial-onset seizures in one of these global studies. More than 200 mg/day of carisbamate is required for efficacy. Carisbamate was well-tolerated in both studies. [source]


Rufinamide: Clinical pharmacokinetics and concentration,response relationships in patients with epilepsy

EPILEPSIA, Issue 7 2008
Emilio Perucca
Summary Rufinamide is a new, orally active antiepileptic drug (AED), which has been found to be effective in the treatment of partial seizures and drop attacks associated with the Lennox-Gastaut syndrome. When taken with food, rufinamide is relatively well absorbed in the lower dose range, with approximately dose-proportional plasma concentrations up to 1,600 mg/day, but less than dose-proportional plasma concentrations at higher doses due to reduced oral bioavailability. Rufinamide is not extensively bound to plasma proteins. During repeated dosing, steady state is reached within 2 days, consistent with its elimination half-life of 6,10 h. The apparent volume of distribution (Vd/F) and apparent oral clearance (CL/F) are related to body size, the best predictor being body surface area. Rufinamide is not a substrate of cytochrome P450 (CYP450) enzymes and is extensively metabolized via hydrolysis by carboxylesterases to a pharmacologically inactive carboxylic acid derivative, which is excreted in the urine. Rufinamide pharmacokinetics are not affected by impaired renal function. Potential differences in rufinamide pharmacokinetics between children and adults have not been investigated systematically in formal studies. Although population pharmacokinetic modeling suggests that in the absence of interacting comedication rufinamide CL/F may be higher in children than in adults, a meaningful comparison of data across age groups is complicated by age-related differences in doses and in proportion of patients receiving drugs known to increase or to decrease rufinamide CL/F. A study investigating the effect of rufinamide on the pharmacokinetics of the CYP3A4 substrate triazolam and an oral contraceptive interaction study showed that rufinamide has some enzyme-inducing potential in man. Findings from population pharmacokinetic modeling indicate that rufinamide does not modify the CL/F of topiramate or valproic acid, but may slightly increase the CL/F of carbamazepine and lamotrigine and slightly decrease the CL/F of phenobarbital and phenytoin (all predicted changes were <20%). These changes in the pharmacokinetics of associated AEDs are unlikely to make it necessary to change the dosages of these AEDs given concomitantly with rufinamide, with the exception that consideration should be given to reducing the dose of phenytoin. Based on population pharmacokinetic modeling, lamotrigine, topiramate, or benzodiazepines do not affect the pharmacokinetics of rufinamide, but valproic acid may increase plasma rufinamide concentrations, especially in children in whom plasma rufinamide concentrations could be increased substantially. Conversely, comedication with carbamazepine, vigabatrin, phenytoin, phenobarbital, and primidone was associated with a slight-to-moderate decrease in plasma rufinamide concentrations, ranging from a minimum of ,13.7% in female children comedicated with vigabatrin to a maximum of ,46.3% in female adults comedicated with phenytoin, phenobarbital, or primidone. In population modeling using data from placebo-controlled trials, a positive correlation has been identified between reduction in seizure frequency and steady-state plasma rufinamide concentrations. The probability of adverse effects also appears to be concentration-related. [source]


Levetiracetam and Partial Seizure Subtypes: Pooled Data from Three Randomized, Placebo-controlled Trials

EPILEPSIA, Issue 12 2003
Ilo E. Leppik
Summary:,Purpose: To determine the effect of levetiracetam (LEV) on partial seizure subtypes (simple partial, complex partial, and secondarily generalized seizures) in patients with refractory epilepsy. Methods: Pooled results from three placebo-controlled trials were analyzed. Results: A statistically significant reduction in the frequency of all partial seizures and all seizure subtypes was observed in the LEV group (p < 0.001 vs. placebo). The proportion of patients in whom secondarily generalized seizures could be prevented over and above the reduction of partial seizures was significantly greater in the LEV group as compared with placebo, with an odds ratio of 1.83 [95% confidence interval (CI), 1.10,3.05]. Conclusions: LEV reduces frequency of simple and complex partial seizures. In addition, it demonstrates a specific, independent reduction of secondarily generalized seizures. [source]


Defining success in clinical trials , profiling pregabalin, the newest AED

EUROPEAN JOURNAL OF NEUROLOGY, Issue 2005
P. Ryvlin
The efficacy and safety of pregabalin as adjunctive therapy for patients with partial epilepsy with or without secondary generalization has been established by four randomized, 12-week, double-blind, placebo-controlled trials (n = 1396) and four long-term open-label studies (n = 1480). Patients in the three fixed-dose trials were ,12 years of age, had ,6 partial seizures and no 4-week seizure-free period during the 8-week baseline period. Seventy-three per cent of patients were taking ,2 concomitant antiepileptic drugs. Responder rates across the effective doses (150,600 mg/day) ranged from 14% to 51% and demonstrated a significant dose,response relationship. The most common adverse events were central nervous system related, generally mild or moderate, transient, and tended to be dose related. The fourth placebo-controlled trial compared a fixed dose of pregabalin 600 mg/day with a flexible-dose regimen (150,600 mg/day). Responder rates were greater for both the fixed dose (45.3%, P < 0.001) and flexible dose (31.3%, P < 0.001) when compared with placebo (11.0%). Compared with the fixed-dose group, the flexible-dose patients had a lower incidence of adverse events and study discontinuations. In long-term open-label trials, the efficacy of pregabalin was maintained with respect to 50% responder rates suggesting no obvious tolerance developing over 2 years. Seizure-free rates were 8.9% and 5.8% for the last 6 months and 1 year of pregabalin treatment, respectively. Long-term open-label pregabalin treatment was well tolerated. [source]


Long-Term Migraine Prevention With Topiramate: Open-Label Extension of Pivotal Trials

HEADACHE, Issue 7 2006
Alan Rapoport MD
Objective.,To demonstrate that topiramate is an effective and generally well-tolerated migraine preventive therapy when used for up to 14 months. Background.,Topiramate 100 and 200 mg/d significantly reduced mean monthly migraine frequency during 2 large, 26-week, randomized, placebo-controlled trials. Only a small number of clinical trials have examined the long-term (,1 year) effectiveness and safety of migraine preventive therapies. Methods.,Five hundred sixty-seven patients with an established history of migraine with or without aura were enrolled in this 8-month, open-label extension of 2 large (49 US and 52 US and Canadian medical centers), randomized, double-blind, placebo-controlled, parallel group, 26-week trials of identical design. To be eligible for the open-label extension, patients were required to have either completed the double-blind phase of the 2 pivotal migraine prevention trials or withdrew after 4 weeks due to lack of efficacy. All eligible patients, regardless of type or dose of study medication (topiramate or placebo) received in the double-blind phase, were titrated to a clinically effective dose of open-label topiramate based on physician judgment of patient response. Efficacy of topiramate was measured as the change in mean monthly migraine frequency. Results.,The mean topiramate dose during the open-label extension phase was 124.7 mg/d and 150.3 mg/d for patients on placebo (n = 159) or topiramate (n = 408), respectively, during the double-blind phase (N = 567, 91% female, mean age 39.4 years). Patients on topiramate for up to 14 months had 2.2 ± 2.4 (mean ± SD) migraines per month after completion of the open-label extension phase (3.4 ± 2.6 at double-blind endpoint). Patients on topiramate during the open-label extension phase only (placebo during the double-blind phase) had 3.0 ± 2.9 migraines per month at open-label extension endpoint (4.9 ± 3.0 migraines per month at double-blind endpoint). Discontinuation rates due to adverse events during the double-blind phase were 22.2% for patients on topiramate and 11.0% for patients on placebo. Discontinuation rates due to adverse events during the open-label extension phase were 8.6% for those patients who had already received topiramate during the double-blind phase and 20.9% for those patients who had previously received placebo. Conclusions.,Patients receiving topiramate experienced a sustained reduction in migraine frequency for up to 14 months. The effectiveness and safety of topiramate was consistent with that observed during 2 26-week pivotal trials. [source]


Botulinum Neurotoxin for the Treatment of Migraine and Other Primary Headache Disorders: From Bench to Bedside

HEADACHE, Issue 2003
David W. Dodick MD
Botulinum toxin type A, a neurotoxin, is effective for treating a variety of disorders of involuntary muscle contraction including cervical dystonia, blepharospasm, and hemifacial spasm. It inhibits neuromuscular signaling by blocking the release of acetylcholine at the neuromuscular junction. The biological effects of the toxin are transient, with normal neuronal signaling returning within approximately 3 to 6 months postinjection. Recent clinical findings suggest that botulinum toxin type A may inhibit pain associated with migraine and other types of headache. However, the mechanism by which this toxin inhibits pain is not fully understood and is under investigation. Research findings suggest that botulinum toxin type A inhibits the release of neurotransmitters from nociceptive nerve terminals and, in this way, may possess an analgesic effect. A number of retrospective open-label chart reviews and 3 double-blind, placebo-controlled trials have demonstrated that localized injections of botulinum toxin type A significantly reduce the frequency, severity, and disability associated with migraine headaches. Although the majority of patients in these studies experienced no botulinum toxin type A-mediated side effects, a small percentage of patients did report transient minor side effects including blepharoptosis, diplopia, and injection-site weakness. Currently, 4 randomized, placebo-controlled, clinical trials are being conducted to evaluate the efficacy, optimal dosing, and side-effect profile of botulinum toxin type A as a novel treatment for migraine and other types of headache. These studies may provide further evidence that botulinum toxin type A is an effective option for the preventive treatment of migraine. [source]


Antiepileptic Drugs in Migraine Prevention

HEADACHE, Issue 2001
Ninan T. Mathew MD
Migraineurs may continue to experience attacks, despite daily use of one or more agents from a wide range of drugs, including , -blockers, calcium channel blockers, serotonin antagonists, tricyclic antidepressants, monoamine oxidase inhibitors, and antiepileptic agents. Divalproex sodium is the only antiepileptic drug approved for migraine prevention. Gabapentin, topiramate, and other antiepileptic agents are being evaluated for migraine prevention and treatment. Prospective, double-blind, placebo-controlled clinical trials of divalproex, gabapentin, and topiramate for migraine prevention generally were composed of a prospective baseline period, a dose titration period, and a fixed-dose treatment period. The primary efficacy variable was a reduction in the 28-day frequency of migraine headache. Patients receiving divalproex for 12 weeks at doses up to 1500 mg/day achieved significant decreases in the migraine frequency (P<.05), corresponding to reductions of 30% to 40% compared with baseline. Nearly half of the divalproex-treated patients had a 50% or more reduction from baseline in headache frequencies (P.05). Asthenia, vomiting, somnolence, tremor, and alopecia were common adverse events associated with divalproex. Significant reductions in migraine frequency were also observed with gabapentin (1800 to 2400 mg/day) when compared with placebo (P<.01), and nearly half of all patients treated at the highest dose experienced a reduction in headache rate of 50% or more. Somnolence was the most commonly reported adverse event among the gabapentin-treated patients. Two single-center, double-blind, placebo-controlled clinical trials evaluated topiramate for migraine prevention. A lower 28-day migraine frequency was seen during 18 weeks of administration at a maximum daily dose of 200 mg (P = .09). In a second study, a significantly lower mean 28-day migraine frequency was observed during 16 weeks of treatment with topiramate (P = .0015). Mean reduction in migraine frequency was also significantly greater in topiramate-treated patients (P = .0037). Paresthesias, diarrhea, somnolence, and altered taste were commonly reported adverse events in the topiramate-treated patients. Unlike some patients given divalproex or gabapentin, some given topiramate reported weight loss. Large, double-blind, placebo-controlled trials may prove the effectiveness of novel antiepileptic drugs in migraine prevention. [source]


How long should a trial of escitalopram treatment be in patients with major depressive disorder, generalised anxiety disorder or social anxiety disorder?

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2009
An exploration of the randomised controlled trial database
Abstract Objective To extend the knowledge of course of improvement in patients with major depressive disorder (MDD), social anxiety disorder (SAD) or generalised anxiety disorder (GAD) participating in randomised placebo-controlled trials (RCTs) and to infer the optimal duration of initial escitalopram treatment in clinical practice, after which intervention might be reasonable in case of non-response. Methods Post hoc analysis of pooled clinical trial database for escitalopram in MDD (14 studies), GAD (4 studies) and SAD (2 studies). ,Onset' of action was defined as a 20% or more decrease from baseline score in disorder-specific psychopathological rating scales: ,response' as a 50% or more decrease from baseline score. Results In MDD, the probability of responding at week 8 if no onset was apparent at week 2 was 43%; in patients with an onset of effect the probability was nearly 80%. Similar patterns were observed in GAD and SAD. The chance of responding beyond week 4 in MDD, GAD and SAD was 20% or less if no effect had occurred by week 2. Conclusions The pattern of response in these RCTs suggests that in patients with MDD, GAD or SAD in wider clinical practice, a period of at least 4,weeks is worthwhile before considering further intervention. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Safety and tolerability of duloxetine in the treatment of major depressive disorder: analysis of pooled data from eight placebo-controlled clinical trials

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 5 2005
James I. Hudson
Abstract Objective To examine the safety and tolerability of the antidepressant duloxetine across multiple studies for major depressive disorder (MDD). Method Safety data were integrated from the acute phases of eight double-blind, placebo-controlled trials in which patients were randomized to duloxetine (40,120,mg/d; n,=,1139) or placebo (n,=,777) for up to 9 weeks. This data set included all acute-phase clinical trials that formed the basis of the New Drug Application (United States) or European Union submission package for duloxetine in the treatment of MDD. Two studies included continuation phases in which acute treatment responders received duloxetine or placebo for an additional 26 weeks. Safety assessments included serious adverse event reports, rates of discontinuation, spontaneously reported treatment-emergent adverse events, changes in vital signs and laboratory values, and electrocardiograms. Results The rates of serious adverse events for duloxetine- and placebo-treated patients were 0.3% and 0.6%, respectively (p,=,0.282). Adverse events led to discontinuation in 9.7% of duloxetine-treated patients, compared with 4.2% of patients receiving placebo (p,<,0.001). Treatment-emergent adverse events with an incidence for duloxetine ,,5.0% and significantly greater than placebo were nausea, dry mouth, constipation, insomnia, dizziness, fatigue, somnolence, increased sweating and decreased appetite. Mean changes in blood pressure and heart rate were small, and the incidence of increases above normal ranges was low. Duloxetine-treated patients had a mean decrease in weight of 0.5,kg compared with an increase of 0.2,kg for patients receiving placebo (p,<,0.001). No significant differences were found between duloxetine and placebo in the incidence of potentially clinically significant laboratory values at anytime while on treatment. Conclusion These results are consistent with those obtained previously from smaller pooled data sets, and suggest that duloxetine is safe and well tolerated in patients with MDD. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Efficacy of methotrexate in ulcerative colitis: Failure or promise

INFLAMMATORY BOWEL DISEASES, Issue 8 2010
Hans H. Herfarth MD
Abstract Background: Low-dose methotrexate is a widely used and efficacious therapy in chronic inflammatory disorders such as psoriasis and rheumatoid arthritis. Prospective randomized controlled trials have demonstrated the efficacy of parenteral methotrexate in Crohn's disease (CD). We performed a systematic review of the efficacy of methotrexate in ulcerative colitis (UC) and discuss the results in the context of the known pharmacokinetics and adverse events of methotrexate therapy in inflammatory bowel diseases and other inflammatory conditions. Materials and Methods: We performed a systematic review of the literature in Medline, Embase, and Web of Science. All publications describing patients with UC treated with methotrexate were included. Results: We identified 12 studies or retrospective case series and 5 meeting abstracts that met the inclusion criteria. Only 1 study reported a prospective randomized placebo-controlled trial using methotrexate at a dose of 12.5 mg orally with no significant clinical benefit. However, the majority of uncontrolled retrospective analyses suggest a clinical response to methotrexate therapy in a range of 30%,80% when the drug is applied by parenteral route in doses between 20,25 mg. Conclusions: The only randomized controlled trial of methotrexate in UC employed oral dosing and doses lower than those shown to be effective in CD and did not demonstrate efficacy, whereas uncontrolled, retrospective studies using doses and routes of administration similar to those employed in CD suggest benefit. Well-designed, prospective, placebo-controlled trials of methotrexate in UC are needed. Inflamm Bowel Dis 2010 [source]


A meta-analysis of the vascular-related safety profile and efficacy of ,-adrenergic blockers for symptoms related to benign prostatic hyperplasia

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 10 2008
J. C. Nickel
Summary Objectives:, To evaluate the safety profile and efficacy of ,1-adrenergic receptor blockers (A1Bs) currently prescribed for benign prostatic hyperplasia (BPH). Data sources:, A systematic literature search of MEDLINE, the Cochrane Database and the Food and Drug Administration Web site through December 2006 identified double-blinded, prospective, placebo-controlled trials, evaluating agents commercially available by prescription for the symptomatic treatment of BPH. Review methods:, Data were reviewed by two investigators with the use of a standardised data abstraction form. Studies were evaluated for methodological quality using the Jadad scale. Studies with a score of < 3 were considered of weaker methodology. Results:, Of 2389 potential citations, 25 were usable for evaluation of safety data, 26 for efficacy. A1B use was associated with a statistically significant increase in the odds of developing a vascular-related event [odds ratio (OR) 2.54; 95% confidence interval (CI): 2.00,3.24; p < 0.0001]. The odds of developing a vascular-related adverse event were: alfuzosin, OR 1.66, 95% CI: 1.17,2.36; terazosin, OR 3.71, 95% CI: 2.48,5.53; doxazosin, OR 3.32, 95% CI: 2.10,5.23 and tamsulosin, OR 1.42, 95% CI: 0.99,2.05. A1Bs increased Qmax by 1.32 ml/min (95% CI: 1.07,1.57) compared with placebo. Difference from placebo in American Urological Association symptom index/International Prostate Symptom Score was ,1.92 points (95% CI: ,2.71 to ,1.14). Conclusions:, Alfuzosin, terazosin and doxazosin showed a statistically significant increased risk of developing vascular-related events compared with placebo. Tamsulosin showed a numerical increase that was not statistically significant. All agents significantly improved Qmax and symptom signs compared with placebo. [source]


Anxiety does not predict response to antidepressant treatment in late life depression: results of a meta-analysis

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 5 2009
J. Craig Nelson
Abstract Objective Previous studies of mixed aged and older adult samples with major depressive disorder (MDD) reported reduced depression response in anxious patients, but a systematic review and analysis has not been performed. Our aim was to determine if anxiety predicts antidepressant response in previously identified placebo-controlled trials of second generation antidepressants for late-life depression. Method From a previous systematic review that identified ten randomized, placebo-controlled trials of community dwelling patients aged 60 or older with major depression, anxious patients were identified by a score ,7 on the anxiety/somatization factor of the Hamilton Depression Rating Scale (HDRS). Response was defined as 50% or greater improvement on the HDRS or the Montgomery Asberg Depression Rating Scale. A meta-analysis was performed using a random effects model to calculate Odds Ratios (OR). Results Data were available from eight trials having ten drug-placebo contrasts that included 2322 anxious and 1387 non-anxious patients. The odds ratio for response to drug compared to placebo in anxious patients was 1.57 (95% CI 1.15, 2.14; z,=,2.86, n,=,10, p,<,0.001), in non-anxious patients was 1.44 (95% CI 1.15, 1.80, z,=,3.21, n,=,10, p,<,0.001), and did not differ between groups. Pooled response rates to drug and placebo respectively were 49.4% vs 37.4% in anxious patients and 44.2 vs 35.5% in non-anxious patients. Conclusions In randomized, placebo-controlled trials, anxiety in late-life depression was not associated with decreased response to second generation antidepressants. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Efficacy and Safety of a Once-Yearly Intravenous Zoledronic Acid 5 mg for Fracture Prevention in Elderly Postmenopausal Women with Osteoporosis Aged 75 and Older

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2010
Steven Boonen MD
OBJECTIVES: To determine the efficacy of once-yearly intravenous zoledronic acid (ZOL) 5 mg in reducing risk of clinical vertebral, nonvertebral, and any clinical fractures in elderly osteoporotic postmenopausal women. DESIGN: A post hoc subgroup analysis of pooled data from the Health Outcome and Reduced Incidence with Zoledronic Acid One Yearly (HORIZON) Pivotal Fracture Trial and the HORIZON Recurrent Fracture Trial. SETTING: Multicenter, randomized, double-blind, placebo-controlled trials. PARTICIPANTS: Postmenopausal women (aged ,75) with documented osteoporosis (T -score ,,2.5 at femoral neck or ,1 prevalent vertebral or hip fracture) or a recent hip fracture. INTERVENTION: Patients were randomized to receive an intravenous infusion of ZOL 5 mg (n=1,961) or placebo (n=1,926) at baseline and 12 and 24 months. MEASUREMENTS: Primary endpoints were incidence of clinical vertebral and nonvertebral and any clinical fracture after treatment. RESULTS: At 3 years, incidence of any clinical, clinical vertebral, and nonvertebral fracture were significantly lower in the ZOL group than in the placebo group (10.8% vs 16.6%, 1.1% vs 3.7%, and 9.9% vs 13.7%, respectively) (hazard ratio (HR)=0.65, 95% confidence interval (CI)=0.54,0.78, P<.001; HR=0.34, 95% CI=0.21,0.55, P<.001; and HR=0.73, 95% CI=0.60,0.90, P=.002, respectively). The incidence of hip fracture was lower with ZOL but did not reach statistical significance. The incidence rate of postdose adverse events were higher with ZOL, although the rate of serious adverse events and deaths was comparable between the two groups. CONCLUSION: Once-yearly intravenous ZOL 5 mg was associated with a significant reduction in the risk of new clinical fractures (vertebral and nonvertebral) in elderly postmenopausal women with osteroporosis. [source]


Testosterone Supplementation Therapy for Older Men: Potential Benefits and Risks

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 1 2003
David A. Gruenewald MD
Serum testosterone levels decline gradually and progressively with aging in men. Many manifestations associated with aging in men, including muscle atrophy and weakness, osteoporosis, reduced sexual functioning, and increased fat mass, are similar to changes associated with testosterone deficiency in young men. These similarities suggest that testosterone supplementation may prevent or reverse the effects of aging. A MEDLINE search was performed to identify studies of testosterone supplementation therapy in older men. A structured, qualitative review was performed of placebo-controlled trials that included men aged 60 and older and evaluated one or more physical, cognitive, affective, functional, or quality-of-life outcomes. Studies focusing on patients with severe systemic diseases and hormone deficiencies related to specific diseases were excluded. In healthy older men with low-normal to mildly decreased testosterone levels, testosterone supplementation increased lean body mass and decreased fat mass. Upper and lower body strength, functional performance, sexual functioning, and mood were improved or unchanged with testosterone replacement. Variable effects on cognitive function were reported, with improvements in some cognitive domains (e.g., spatial, working, and verbal memory). Testosterone supplementation improved exercise-induced coronary ischemia in men with coronary heart disease, whereas angina pectoris was improved or unchanged. In a few studies, men with low testosterone levels were more likely to experience improvements in lumbar bone mineral density, self-perceived functional status, libido, erectile function, and exercise-induced coronary ischemia with testosterone replacement than men with less marked testosterone deficiency. No major unfavorable effects on lipids were reported, but hematocrit and prostate specific antigen levels often increased. Based on these results, testosterone supplementation cannot be recommended at this time for older men with normal or low-normal testosterone levels and no clinical manifestations of hypogonadism. However, testosterone replacement may be warranted in older men with markedly decreased testosterone levels, regardless of symptoms, and in men with mildly decreased testosterone levels and symptoms or signs suggesting hypogonadism. The long-term safety and efficacy of testosterone supplementation remain uncertain. Establishment of evidence-based indications will depend on further demonstrations of favorable clinical outcomes and symptomatic, functional, and quality-of-life benefits in carefully performed, long-term, randomized, placebo-controlled clinical trials. J Am Geriatr Soc 51:101,115, 2003. [source]


Considerations for Development of Surrogate Endpoints for Antifracture Efficacy of New Treatments in Osteoporosis: A Perspective,,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2008
Mary L Bouxsein
Abstract Because of the broad availability of efficacious osteoporosis therapies, conduct of placebo-controlled trials in subjects at high risk for fracture is becoming increasing difficult. Alternative trial designs include placebo-controlled trials in patients at low risk for fracture or active comparator studies, both of which would require enormous sample sizes and associated financial resources. Another more attractive alternative is to develop and validate surrogate endpoints for fracture. In this perspective, we review the concept of surrogate endpoints as it has been developed in other fields of medicine and discuss how it could be applied in clinical trials of osteoporosis. We outline a stepwise approach and possible study designs to qualify a biomarker as a surrogate endpoint in osteoporosis and review the existing data for several potential surrogate endpoints to assess their success in meeting the proposed criteria. Finally, we suggest a research agenda needed to advance the development of biomarkers as surrogate endpoints for fracture in osteoporosis trials. To ensure optimal development and best use of biomarkers to accelerate drug development, continuous dialog among the health professionals, industry, and regulators is of paramount importance. [source]


Systematic review of the efficacy of antiretroviral therapies for reducing the risk of mother-to-child transmission of HIV infection

JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 3 2007
N. Suksomboon PhD
Summary Objective:, To evaluate the efficacy of antiretroviral therapies in reducing the risk of mother-to-child transmission of HIV infection. Methods:, Systematic review and meta-analysis of randomized controlled trials. Clinical trials of antiretrovirals were identified through electronic searches (MEDLINE, EMBASE, BIOSIS, EBM review and the Cochrane Library) up until November 2006. Historical searches of reference lists of relevant randomized controlled trials, and systematic and narrative reviews were also undertaken. Studies were included if they were (i) randomized controlled trials of any antiretroviral therapy aimed at decreasing the risk of mother-to-child transmission of HIV infection, (ii) reporting outcomes in terms of HIV infection in infant, infant death, stillbirth, premature delivery, or low birth weight. The data were extracted by a single investigator and checked by a second investigator. Disagreements were resolved through discussion or a third investigator. The efficacy was estimated using relative risk (RR), risk difference (RD) and number needed to treat (NNT) together with 95% confidence intervals. Results:, Fifteen trials were included in the systematic review. Based on five placebo-controlled trials, a zidovudine regimen reduced the risk of mother-to-child transmission by 43% (95% CI: 29,55%). The incidence of low birth weight seems to be decreased with zidovudine (pooled RR 0·75, 95% CI: 0·57,0·99). The efficacy of short-short course of zidovudine was comparable with that of the long-short course. Nevirapine monotherapy given to mothers and babies as a single dose reduced the risk of vertical transmission compared with an intrapartum and post-partum regimen of zidovudine (RR 0·60, 95% CI: 0·41,0·87). Zidovudine plus lamivudine was effective in reducing the risk of maternal-child transmission of HIV (RR 0·63, 95% CI: 0·45,0·90). Adding zidovudine to single-dose nevirapine in babies was no more effective than nevirapine alone (pooled RR 0·88, 95% CI: 0·47,1·63), nor was there any significant difference between zidovudine plus lamivudine and nevirapine. In mothers who were treated with standard antiretroviral therapy, no additional benefit was observed with the addition of a single dose of nevirapine in mothers and newborns. In addition, for mothers who received zidovudine prophylaxis, a two-dose intrapartum/newborn nevirapine reduced the risk of HIV infection and death of babies by 68% (95% CI: 39,83%) and 80% (95% CI: 10,95%), respectively, when compared with placebo. Conclusions:, The available evidence suggests that zidovudine alone or in combination with lamivudine and nevirapine monotherapy is effective for the prevention of mother-to-child transmission of HIV. They may also be beneficial in reducing the risk of infant death. Different antiretroviral regimens appear to be comparably effective in reducing HIV transmission from mothers to babies. In mothers already receiving zidovudine prophylaxis, adding a single dose of nevirapine to mothers during labour and giving the same drug to infants may further decrease the risk of vertical transmission and infant death. [source]


A meta-analysis of the effects of internet- and computer-based cognitive-behavioral treatments for anxiety

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 1 2009
Mark A. Reger
Abstract Internet-and computer-based cognitive-behavioral treatments have been introduced as novel approaches to deliver standard, quality treatment that may reduce barriers to care. The purpose of this review is to quantitatively summarize the literature examining the treatment effects of Internet- or computer-based treatment (ICT) on anxiety. Nineteen randomized controlled ICT trials were identified and subjected to fixed and random effects meta-analytic techniques. Weighted mean effect sizes (Cohen's d) showed that ICT was superior to waitlist and placebo assignment across outcome measures (ds=.49,1.14). The effects of ICT also were equal to therapist-delivered treatment across anxiety disorders. However, conclusions were limited by small sample sizes, the rare use of placebo controls, and other methodological problems. In addition, the number of available studies limited the opportunity to conduct analyses by diagnostic group; there was preliminary support for the use of ICT for panic disorder and phobia. Large, well-designed, placebo-controlled trials are needed to confirm and extend the results of this meta-analysis. © 2008 Wiley Periodicals, Inc. J Clin Psychol 65: 1,21, 2009. [source]


Placebo psychotherapy: Synonym or oxymoron?

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 7 2005
Irving Kirsch
Contrary to some recent claims, the placebo effect is real and in some cases very substantial. Placebo effects can be produced or enhanced by classical conditioning, but consistent with virtually all contemporary conditioning theories, these effects are generally mediated by expectancy. Expectancy can also produce placebo effects that are inconsistent with conditioning history. Although expectancy also plays an important role in psychotherapy outcome, the logic of placebo-controlled trials does not map well onto psychotherapy research. The idea of evaluating the efficacy of psychotherapy by controlling for nonspecific or placebo factors is based on a flawed analogy and should be abandoned. © 2005 Wiley Periodicals, Inc. J Clin Psychol 61: 791,803, 2005. [source]


The role of probiotics and prebiotics in the management of diarrhoea associated with enteral tube feeding

JOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 6 2001
K. Whelan
Introduction Diarrhoea is a common and serious complication of enteral tube feeding, and has a range of aetiologies. Manipulation of the colonic microflora may reduce the incidence of enteral tube feeding diarrhoea via suppression of enteropathogens and production of short-chain fatty acids. Probiotics and prebiotics are commonly used during enteral tube feeding to manipulate the colonic microflora; however, their efficacy is as yet uncertain. Methods English-language studies investigating the pathogenesis of enteral tube feeding diarrhoea and the use of probiotics and prebiotics were identified by searching the electronic databases CINAHL, EMBASE and MEDLINE from 1980 to 2001. The bibliographies of articles obtained were searched manually. Results Only two prospective, randomized, double-blind, placebo-controlled trials have investigated the effect of a probiotic on enteral tube feeding diarrhoea; however, results are conflicting. No prospective, randomized, double-blind, placebo-controlled studies have specifically addressed the effect of a prebiotic on the incidence of enteral tube feeding diarrhoea. Conclusion Theoretically, probiotics and prebiotics may be of benefit in prophylaxis against enteral tube feeding diarrhoea; however, there is currently insufficient evidence to support their routine use. Prospective, randomised, double-blind, placebo-controlled studies investigating their effect on diarrhoea are required. These observations are discussed with reference to the current literature. [source]


A Review of the Evidence Comparing the Human Papillomavirus Vaccine Versus Condoms in the Prevention of Human Papillomavirus Infections

JOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 3 2008
Shelley Miksis
ABSTRACT Objective:, To examine the evidence related to the efficacy of condom use versus the human papillomavirus vaccine in the prevention of human papillomavirus infections. Data sources:, Cochrane, CINHAL, PubMed, and Clinical Evidence. Various combinations of the keywords HPV, vaccine, and condoms were used for the search. Study selection:, Randomized, double-blinded placebo-controlled trials were reviewed for evaluation of the human papillomavirus vaccine. Several longitudinal studies and a meta-analysis were used for review of condom efficacy related to human papillomavirus transmission. Data extraction and synthesis:, Studies evaluating the use of either condoms or the human papillomavirus vaccine and its impact on human papillomavirus transmission rates, detected through either human papillomavirus DNA testing or clinical disease. Conclusions:, The evidence indicates that the greatest degree of protection from specific types of human papillomavirus infection is provided by the vaccine. However, the use of condoms in addition to the human papillomavirus vaccine provides the greatest protection from the untoward effects of human papillomavirus infection and may also provide protection against human papillomavirus types not in the vaccine and other sexually transmitted infections. [source]


The Efficacy of Acamprosate in the Maintenance of Abstinence in Alcohol-Dependent Individuals: Results of a Meta-Analysis

ALCOHOLISM, Issue 1 2004
Karl Mann
Abstract: Background: A number of clinical trials have been undertaken to determine the efficacy of acamprosate in the maintenance of abstinence in alcohol-dependent individuals. However, the reported differences in patient populations, treatment duration, and study endpoints make comparisons difficult. An assessment of the efficacy of treatment with acamprosate was, therefore, undertaken using meta-analytical techniques. Methods: All randomized, placebo-controlled trials (RCTs) that fulfilled predetermined criteria were identified using (1) a language unrestricted search of 10 electronic databases; (2) a manual search of relevant journals, symposia, and conference proceedings; (3) cross-referencing of all identified publications; (4) personal communications with investigators; and (5) scrutiny of Merck-Santé's internal reports of all European trials. Study quality was assessed, independently, by three blinded workers. Key outcome data were identified; some outcome variables were recalculated to ensure consistency across trials. The primary outcome measure was continuous abstinence at 6 months; abstinence rates were determined by estimating Relative Benefit (RB). Results: A total of 19 published 1 unpublished RCTs were identified that fulfilled the selection criteria; 3 were excluded because the documentation available was insufficient to allow adequate assessment. The remaining 17 studies, which included 4087 individuals, 53% of whom received active drug, were of good quality and were otherwise reasonably comparable. There was no evidence of publication bias. Continuous abstinence rates at 6 months were significantly higher in the acamprosate-treated patients (acamprosate, 36.1%; placebo, 23.4%; RB, 1.47; [95% confidence intervals (CI): 1.29,1.69]; p < 0.001). This effect was observed independently of the method used for assigning missing data. The effect sizes in abstinent rates at 3, 6, and 12 months were 1.33, 1.50, and 1.95, respectively. At 12 months, the overall pooled difference in success rates between acamprosate and placebo was 13.3% (95% CI, 7.8,18.7%; number needed to treat, 7.5). Acamprosate also had a modest but significant beneficial effect on retention (6.01%; [95% CI, 2.90,8.82]; p= 0.0106). Conclusion:: Acamprosate has a significant beneficial effect in enhancing abstinence in recently detoxified, alcohol-dependent individuals. [source]


Placebo Effect in Canine Epilepsy Trials

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2010
K.R. Muñana
Background: The placebo effect is a well-recognized phenomenon in human medicine; in contrast, little information exists on the effect of placebo administration in veterinary patients. Hypothesis: Nonpharmacologic therapeutic effects play a role in response rates identified in canine epilepsy trials. Animals: Thirty-four dogs with epilepsy. Methods: Meta-analysis of the 3 known prospective, placebo-controlled canine epilepsy trials. The number of seizures per week was compiled for each dog throughout their participation in the trial. Log-linear models were developed to evaluate seizure frequency during treatment and placebo relative to baseline. Results: Twenty-two of 28 (79%) dogs in the study that received placebo demonstrated a decrease in seizure frequency compared with baseline, and 8 (29%) could be considered responders, with a 50% or greater reduction in seizures. For the 3 trials evaluated, the average reduction in seizures during placebo administration relative to baseline was 26% (P= .0018), 29% (P= .17), and 46% (P= .01). Conclusions and Clinical Importance: A positive response to placebo administration, manifesting as a decrease in seizure frequency, can be observed in epileptic dogs. This is of importance when evaluating open label studies in dogs that aim to assess efficacy of antiepileptic drugs, as the reported results might be overstated. Findings from this study highlight the need for more placebo-controlled trials in veterinary medicine. [source]


Botulinum neurotoxins for post-stroke spasticity in adults: A systematic review,,

MOVEMENT DISORDERS, Issue 6 2009
Antonio Emanuele Elia MD
Abstract The aim of this systematic review was to determine whether botulinum neurotoxin (BoNT) reduce spasticity or improve function in adult patients after stroke. Eleven double-blind randomized placebo-controlled trials met inclusion criteria. They encompassed 782 patients, 767 (98%) of whom received BoNT/A, and 15 (2%) BoNT/B. Most studies used the Ashworth scale as primary outcome measure. Differences between treated and control groups were assessed as categorical or continuous comparisons. The overall effect on upper limb spasticity was in favor of BoNT/A. A significantly higher number of patients had a reduction of upper limb spasticity at 4-week and 8-week evaluations in the treatment group compared with placebo. Mean changes in joint spasticity revealed improvement 3 to 6 weeks and 9 to 12 weeks after treatment. There were insufficient data to establish BoNT/A efficacy on lower limb spasticity or the effect of BoNT/B on the upper and lower limbs. Because of inconsistency and heterogeneity of the available data, it was not possible to perform a meta-analysis on disability and patients' reported outcomes. There was an overlapping safety profile between the treatment and the placebo groups. BoNT/A reduces upper limb spasticity in patients post-stroke, but the improvement in functional ability remains to be established. This gap needs to be filled by new studies to assess the effect of BoNT in the context of multidisciplinary patient management. © 2009 Movement Disorder Society [source]


Are delayed-start design trials to show neuroprotection in Parkinson's disease fundamentally flawed?

MOVEMENT DISORDERS, Issue 6 2008
Carl E. Clarke BSc, FRCP
Abstract Considerable effort has gone into preclinical neuroprotection research in Parkinson's disease (PD) and several large clinical trials have been mounted, but no agent has been conclusively shown to be protective. The latest innovation in PD neuroprotection trial design is the delayed-start design trial. If patients with early PD do better after 12 to 18 months of immediate drug therapy compared to those in whom it is delayed for 6 to 9 months, this is attributed to a neuroprotective effect. However, delayed-start design trials may be fundamentally flawed. It has been suggested that physiological mechanisms compensating for the loss of dopaminergic neurones in early PD may be deleterious and that immediate treatment may prevent such mechanisms and thereby be neuroprotective. If this hypothesis is correct, any drug with a symptomatic effect will be neuroprotective in early PD and delayed-start design trials will show this generic effect, not a neuroprotective effect specific to the drug. Delayed-start design trials require patients to potentially stay untreated for 6 to 9 months. This may lead to the selection of slowly progressive types of PD, such as that in younger patients and those with tremor-dominant disease, so the results may not be generalizable to the majority of patients. Delayed-start design trials are powered to find small differences in total UPDRS score which may not be clinically significant; larger and longer placebo-controlled trials are required to confirm the clinical significance of their findings. These arguments add to the growing tide of opinion for a fundamental rethink of our policy toward neuroprotection research in PD. © 2008 Movement Disorder Society [source]


Efficacy of alosetron in irritable bowel syndrome: a meta-analysis of randomized controlled trials

NEUROGASTROENTEROLOGY & MOTILITY, Issue 1 2003
F. Cremonini
Abstract The 5HT3 receptor antagonist alosetron has been tested in several trials on irritable bowel syndrome (IBS) patients. The aim of the present meta-analysis was to determine its effect on adequate relief of pain or global improvement of symptoms in IBS patients. Six large, multicentre, randomized, placebo-controlled trials fulfilled pre-set criteria for high quality and were included in the meta-analysis; 1762 patients were randomized to alosetron treatment and 1356 to placebo. Seventy-five per cent of the patients experienced diarrhoea-predominant IBS and 93% were females. The pooled odds ratio for adequate relief of pain or global symptoms improvement was 1.81 [95% confidence interval (CI) 1.57,2.10). The average number of patients needed to treat with alosetron for one patient to achieve improvement over placebo treatment was seven (95% CI 5.74,9.43). The present analysis shows that alosetron 1 mg b.i.d. positively impacts global symptoms, and pain and discomfort in non-constipated IBS female patients. One in four patients treated with alosetron may develop constipation. The efficacy of alosetron is unclear in male patients. [source]


Zinc Nutrition and HIV Infection

NUTRITION REVIEWS, Issue 3 2002
Roland Kupka BS
The trace element zinc is involved in many important immune processes. A number of immunologic impairments owing to zinc deficiency are also evident in HIV disease, most notably a reduction in the number of circulating T lymphocytes. Observational epidemiologic studies have provided conflicting results on the role of zinc status in HIV disease progression. Randomized, placebo-controlled trials are needed to resolve this controversy. Studies must also address the role of zinc in vertical transmission of HIV from mother to child and its role in reducing the risk of adverse pregnancy outcomes, both of which are of considerable public health importance in developing countries. [source]


Targeted Pharmacotherapy of Evoked Phenomena in Neuropathic Pain: A Review of the Current Evidence

PAIN MEDICINE, Issue 1 2007
BSc(Med), Ron Granot MB BS
ABSTRACT Objective., Evoked phenomena in clinical neuropathic pain are viewed as a window into the underlying pathophysiology. They are also potential therapeutic targets. This study sought evidence for the effect on such evoked phenomena of currently used agents. Design., We reviewed MEDLINE (1966,2006) and EMBASE (1980,2006) to locate all randomized, double-blind, placebo-controlled trials examining therapeutic responses of evoked neuropathic pain phenomena, including dynamic mechanical allodynia, pin prick hyperalgesia, and thermal allodynia. We also noted the methods of elicitation of these evoked pain phenomena. Results., We found 40 articles meeting our inclusion criteria. A wide variety of methods was used to evoke neuropathic pain phenomena. For dynamic mechanical allodynia, there is some evidence for the efficacy of ketamine, alfentanil, and morphine, but only when administered intravenously. For other agents and other evoked pain phenomena, there is insufficient evidence to draw firm conclusions. Conclusions., There is minimal evidence to guide clinicians in treating evoked pain phenomena in clinical neuropathic pain states. There is little clinical evidence to either support or refute theoretical arguments for efficacy of specific agents in evoked neuropathic pain phenomena. More and larger trials are needed to examine these phenomena. Consensus is required with respect to methods used to elicit these evoked phenomena. [source]


Zoledronic acid for the treatment of osteopenia in pediatric Crohn's disease

PEDIATRICS INTERNATIONAL, Issue 5 2010
Anne Marie Sbrocchi
Abstract Background:, Pediatric patients with Crohn's disease often have low bone mass (osteopenia) for age. No randomized, placebo-controlled trials using zoledronic acid have ever been performed in this population. The objective of this study was to assess the efficacy of zoledronic acid in children with Crohn's disease and osteopenia. Methods:, A double-blind, randomized, placebo-controlled design was used. Thirteen adolescents received either a single intravenous dose of zoledronic acid (0.066 mg/kg, max 4 mg, n= 7) or saline placebo (n= 6). The primary outcome was change in lumbar spine bone mineral density (LSBMD) z-score at 6 months. Secondary outcomes included bone markers and adverse events. Results:, At 6 months, the change in LSBMD z-score was significantly higher in the zoledronic acid group compared to placebo (0.7 vs 0.1, P < 0.001). Volumetrically adjusted LSBMD z-score also significantly increased in the treated group. This significant difference persisted until 12 months. With zoledronic acid, urinary C-telopeptide excretion decreased by 50% at 6 months and remained suppressed at 12 months (P= 0.02), but no changes were observed with placebo. Both groups had similar adverse events which included transient fever, arthralgias, and nausea (3/7 treated, 2/6 placebo, P= NS). Conclusions:, In this study, zoledronic acid demonstrated a significant increase in LSBMD at 6 and 12 months following a well-tolerated infusion. [source]