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Results of a randomized double-blind placebo-controlled trial evaluating sequential high-dose cytosine arabinoside/mitoxantrone chemotherapy with or without granulocyte/macrophage-colony-stimulating factor in high-risk myelodysplastic syndromes.

A prospective, randomized, double-blind placebo-controlled trial was designed to evaluate the impact of granulocyte/macrophage-colony-stimulating factor (GM-CSF) on the efficacy of sequential high-dose cytosine arabinoside/mitoxantrone chemotherapy (S-HAM) in adult patients with high-risk myelodysplastic syndromes (MDS). GM-CSF or placebo was given subcutaneously once daily at a dose of 250 microg/m2, starting 48 h prior to chemotherapy, and continued until neutrophil recovery. Owing to high toxicity and slow patient recruitement the study was closed and unblinded after 31 patients had been enrolled; 15 were randomized to receive placebo and 16 to receive GM-CSF. A total of 29 patients were evaluable for response; their median age was 57 years. Ten patients achieved a complete remission (34.5%), 9 patients had persistent MDS (31%), 10 patients died within 6 weeks after the onset of treatment (early death) (34.5%). The median remission duration was 190 days (range: 2.5-45 months). Among the 29 evaluable patients no significant differences could be found between the two study arms regarding complete remission rate [GM-CSF: 31% (5/16) versus placebo: 38% (5/13) P = 0.45], rate of persistent MDS [GM-CSF: 25% (4/16) versus 38% (5/13) P = 0.35), early death rate [44% (7/16) versus 23% (3/13) P = 0.22] and remission duration (GM-CSF: 87 days versus placebo 221 days). Duration of granulocytopenia (median: 33 days with GM-CSF) versus 35 days with placebo) and frequency of infectious episodes were not significantly influenced by GM-CSF. The small number of patients finally analyzed means that no definite conclusions about the effect of GM-CSF can be reached.

Adult↗

Efficacy of budipine and placebo in untreated patients with Parkinson's disease.

Previous studies demonstrated the efficacy of budipine on motor symptoms of treated patients with Parkinson's disease (PD) with rating scales. However rating procedures may be subjective and variable. Therefore additional use of instrumental motor tests are helpful to reflect therapeutic benefits. Objective was to test the efficacy of 20 mg budipine (t.i.d.) in 51 previously untreated idiopathic PD patients in a monocenter, double-blind, placebo-controlled trial with a 2:1 randomisation over a three month interval. Budipine was not superior to placebo application. However a detailed analysis of rating results shows, that budipine but not placebo treated patients significantly improved. Budipine caused significant better outcomes of motor tests with execution of complex movements, but did not change results of tasks, which demand for simple motions. Placebo significantly improved dopamine sensitive motor test results. These outcomes may result from improved non dopaminergic neurotransmission due to budipine. Placebo caused better results of dopamine sensitive tests, since placebo may release endogenous dopamine.

Adult↗

Effect of transcutaneous electrical nerve stimulation on pain perception threshold of human teeth: a double-blind, placebo-controlled study.

In this double-blind, placebo-controlled study, we studied the effect of three different transcutaneous electrical nerve stimulation (TENS) devices with extra- and intraoral electrodes on the pain perception thresholds of 234 unrestored, caries-free human teeth of 66 healthy individuals subjected to stimulation with an electric pulp tester. A placebo control collective of 64 healthy subjects received no electrical stimulation, since an inactive TENS device was used. In all tooth types tested (maxillary and mandibular incisors and premolars), the use of the active TENS devices resulted in an increase of 16.3-32.5% versus baseline in the pain perception threshold. The differences between active TENS and baseline were statistically significant for both TENS devices using extraoral electrodes (P < 0.05). No statistically significant differences were found between the different devices tested (P > 0.05). In the placebo collective, the increase in the pain perception threshold ranged between 6.4% and 10.3% versus baseline. There were no significant differences between placebo TENS and baseline on the one hand and between placebo TENS and the active TENS devices on the other hand (P > 0.05). The findings suggest that, as an alternative to local anesthetics, TENS seems not to be useful in the case of painful dental interventions, since it offered only minor advantages over a placebo.

Adult↗

A prospective, randomized, double-blind, placebo-controlled trial of retinol palmitate (vitamin A) for symptomatic chronic radiation proctopathy.

PURPOSE: This study was designed to determine whether oral retinol palmitate (vitamin A) can reduce the symptoms of radiation proctopathy. METHODS: A randomized, double-blind trial comparing retinol palmitate (10,000 IU by mouth for 90 days) to placebo was conducted. Eligible patients were more than six months postpelvic radiotherapy and had significant symptoms as measured with the Radiation Proctopathy System Assessments Scale. Nineteen patients were randomized in total: ten to retinol palmitate and nine to placebo. The Radiation Proctopathy System Assessments Scale scores before and every 30 days for 90 days were measured. Five placebo nonresponders were crossed over to the retinol palmitate for another 90 days. Response was defined as a reduction in two or more symptoms by at least two Radiation Proctopathy System Assessments Scale points. RESULTS: Seven of ten retinol palmitate patients responded, whereas two of nine responded to placebo (P = 0.057). Mean pre-post-treatment change in Radiation Proctopathy System Assessments Scale (delta Radiation Proctopathy System Assessments Scale) in the retinol palmitate group was 11 +/- 5, whereas delta Radiation Proctopathy System Assessments Scale in the placebo group was 2.5 +/- 3.6 (P = 0.013, Mann-Whitney U test). Additionally, all five placebo nonresponders who were crossed over to treatment with retinal palmitate responded to treatment. CONCLUSIONS: In our trial, retinol palmitate significantly reduced rectal symptoms of radiation proctopathy, perhaps because of wound-healing effects. The current results can serve as the foundation for future trials examining retinol palmitate in the multi-institutional setting.

Aged↗

Acebutolol in essential hypertension: results of two multicenter studies against placebo and propranolol.

Two double-blind multicenter studies compared acebutolol with placebo (acebutolol, N = 121; placebo, N = 116) and with propranolol (acebutolol, N = 186; propranolol, N = 190) in essential hypertension. Acebutolol significantly reduced mean sitting diastolic blood pressure from 99.2 +/- 0.3 mm Hg at baseline to 89.1 +/- 0.9 mm Hg at the end of dose titration (p = 0.001). Significantly more acebutolol patients (65%) achieved therapeutic goal than did placebo patients (28%, p less than 0.01). The reduction in heart rate in acebutolol-treated patients (9.2 bpm) was greater than in placebo-treated patients (1.2 bpm, p = 0.001). The incidence of side effects and the number of patients discontinued because of side effects did not significantly differ between acebutolol and placebo. Acebutolol and propranolol produced comparable reductions in diastolic, systolic, and mean arterial blood pressures (p less than 0.001). At equipotent doses the 13% decrease in heart rate in patients receiving acebutolol was significantly less than the 17% decrease in propranolol patients (p = 0.02). The number of patients experiencing central nervous system (CNS) side effects while receiving acebutolol (N = 50) was significantly less than with propranolol (N = 75, p = 0.001), and significantly fewer acebutolol patients (N = 11) were discontinued because of side effects compared with propranolol patients (N = 29, p less than 0.01). Laboratory, ECG, or chest X-ray results did not differ for acebutolol, placebo, or propranolol. Acebutolol appears to be safe and effective in the management of mild to moderately severe essential hypertension and is better tolerated than propranolol in terms of CNS side effects, with a significantly lesser effect on heart rate.

Acebutolol↗

The placebo effect in heart failure.

Many patients who are enrolled in controlled clinical trials of new drugs for the treatment of heart failure show favorable hemodynamic and clinical responses to placebo therapy. This "placebo effect" results from both the creation of a supportive therapeutic environment and the spontaneous improvement that is commonly seen when measurements of symptoms and cardiac function are repeated frequently over long intervals of time. Three months of treatment with a placebo produces a reduction in symptoms in 25% to 35% of patients, an increase in cardiac output and a decrease in pulmonary wedge pressure, and an increase in exercise tolerance of up to 90 to 120 seconds. Physicians commonly seek to maximize the "placebo effect," since the goal of treatment in the clinical setting is to improve the quality of the patient's life. On the other hand, clinical investigators seek to minimize the "placebo effect," since the goal of a research study is to test the hypothesis that the new drug is superior to a placebo.

Heart Failure↗

Verapamil therapy for unstable angina pectoris: review of double-blind placebo-controlled randomized clinical trials.

The effectiveness of verapamil in the management of patients with unstable angina pectoris associated with obstructive coronary artery disease was evaluated in 2 double-blind placebo-controlled randomized clinical trials. In the 1st study, verapamil was compared with placebo using alternating 48 hour treatment periods in a multiple cross-over protocol. Verapamil was superior to placebo in abolishing symptomatic and asymptomatic ischemic episodes; there were 127 ischemic events during treatment with placebo but only 27 episodes during therapy with verapamil (p less than 0.006). In the 2nd study, verapamil and placebo were compared using a double-blind randomized parallel design in which the choice of drug was altered and the doses administered were increased according to the individual responses. Verapamil reduced anginal attacks in 12 of 13 patients, but placebo was effective in only 1 of 6 (p less than 0.025); verapamil reduced daily anginal attacks from 3.2 to 0.6/day (p less than 0.01). Thus, verapamil is highly effective in the short-term management of patients with unstable angina secondary to coronary artery disease.

Adult↗

Does placebo improve indexes of effort-induced myocardial ischemia? An objective study in 150 patients with chronic stable angina pectoris.

The effects of placebo were studied in 150 patients (135 men, 15 women) aged 42 to 75 years with stable exertional angina pectoris, using multistage graded exercise testing. Treadmill exercise, using on-line computer analysis of the electrocardiogram, was performed after a basal period, during which time the patients had no treatment for 2 weeks, and after 2 weeks of placebo therapy. Mean exercise time during no treatment was 6.0 +/- 0.2 minutes and during placebo was 6.1 +/- 0.2 minutes (difference not significant). Similarly, time to development of 1 mm of ST-segment depression of 4.0 +/- 0.2 minutes without treatment was 4.1 +/- 0.2 minutes after 2 weeks of placebo therapy (difference not significant). Placebo failed to show any effect on rest or maximal heart rate or on maximal ST-segment depression. It also failed to increase exercise tolerance or to improve other objective indexes of effort-induced myocardial ischemia in both single-and double-blind protocols in patients with stable exertional angina pectoris. Therefore, placebo control of antianginal drug trials that use exercise testing for evaluation of effect is unnecessary and can be omitted.

Adult↗

Randomized, double-blind, placebo-controlled crossover trial of cimetidine and pirenzepine in nonulcer dyspepsia.

Nonulcer dyspepsia remains a difficult disorder to treat because it is a heterogeneous syndrome. Once patients with the irritable bowel syndrome, esophagitis, and other organic diseases are excluded, there remain patients with dyspepsia of unknown cause (termed "essential dyspepsia") and patients with dyspepsia plus symptoms of gastroesophageal reflux without esophagitis. The aim of this study was to determine whether cimetidine or pirenzepine is efficacious in relieving the symptoms of these latter subgroups. Sixty-two consecutive patients were studied who had chronic upper abdominal pain or nausea where endoscopy had shown no evidence of peptic ulceration, esophagitis, or malignancy; 47 had essential dyspepsia, and 15 had dyspepsia plus gastroesophageal reflux. They were initially randomized to either cimetidine or placebo, or pirenzepine or placebo. Patients continued each medication for 1 mo, and, after a washout period, crossed over when again symptomatic; 51 patients completed cimetidine and placebo, and 50 completed pirenzepine and placebo. The results showed that cimetidine was superior to placebo in decreasing the number of upper abdominal pain episodes weekly and the severity of pain, but the absolute improvement was small. Pirenzepine was not superior to placebo in decreasing symptoms.

Adult↗

The problems of taste in placebo matching: an evaluation of zinc gluconate for the common cold.

A recently published randomized, controlled, double-blind, study has reported efficacy of zinc gluconate lozenge treatment of the common cold. Because of a higher rate of side effects in the zinc group and the lack of any confirmatory evidence of blinding efficacy, we are concerned about the possible contribution of bias to the study result. Unflavored zinc gluconate tablets can be easily distinguished from the relatively tasteless, unflavored calcium lactate tablets, which were used as placebo in the cited study, increasing our concern about bias. In order to be able to test zinc lozenges in a second trial of common cold therapy, we developed a matching placebo containing denatonium benzoate (a bitter substance used to prevent thumb sucking in children) and then undertook a formal evaluation of blinding efficacy. This article reports the results of this evaluation, encompassing two randomized, controlled taste trials; the first trial of the placebo matching showed zinc recipients to exhibit a higher rate of side effects and also a significantly higher proportion of subjects believing they were on "active" treatment. Alterations in dosage before the second taste trial yielded comparability of the placebo and zinc lozenges. This study illustrates the pitfalls which may sometimes be encountered in performing and publishing studies in which placebos are either not tested at all or tested in too small a subject population to detect a significant subjective difference between the placebo and the active medication.

Clinical Trials as Topic↗

Treatment of the hyperventilation syndrome with bisoprolol: a placebo-controlled clinical trial.

The hyperventilation syndrome (HVS) can be regarded as a form of panic disorder associated with a relative increase in sympathomimetic tone, the effects of which can be counterbalanced by beta-adrenoceptor blockade. The efficacy of the beta-blocker bisoprolol was investigated in a double-blind placebo-controlled randomised crossover trial involving 60 patients from 17 general practices. Following a single-blind placebo prephase, patients who met the inclusion criteria were randomised to treatment with either 5 mg bisoprolol or an identical-looking placebo tablet once daily for three weeks. They were then crossed over to the other treatment arm. At the end of each treatment phase the number of hyperventilation attacks and the severity of symptoms were assessed and side effects recorded. The number of attacks decreased from 4.04 per week at baseline to 3.52 with placebo and to 1.26 with bisoprolol. The decrease of attacks with bisoprolol was significant (p < 0.05) compared to baseline and placebo. The severity of the complaints improved from 29 (scale 0 to 64) at baseline not significantly to 26 with placebo and significantly (p < 0.05) to 15 with bisoprolol. No serious side effects were reported. Five milligrams of bisoprolol once daily is effective and safe in the maintenance of symptom reduction in patients with the hyperventilation syndrome.

Adult↗

Narcotic receptor blockade and its effect on the analgesic response to placebo and ibuprofen after oral surgery.

The purpose of this study was to evaluate the contribution of endogenous opiates to the analgesic response after treatment with placebo, codeine, and ibuprofen after oral surgery. Eighty-one patients undergoing complicated dental extractions were pretreated with either a placebo or the narcotic antagonist naltrexone 50 mg, 30 minutes before surgery. After surgery, patients self administered one of three possible postsurgical medications, which included placebo, codeine 60 mg, and ibuprofen 400 mg, when their pain reached a moderate or severe intensity. The study was double-blind with the three postsurgical treatments being randomly allocated within each presurgical treatment block. Pain intensity, pain relief, pain half gone, and overall evaluations were assessed for up to 6 hours. Ibuprofen was significantly more efficacious (p < .05) than codeine or placebo for most analgesic measures. The administration of naltrexone before surgery reduced the analgesic response to both placebo and codeine. Pretreatment with naltrexone did not diminish the peak analgesic response to ibuprofen, but surprisingly prolonged (p < .05) the duration of its action. The results suggest that a blockade of endogenous opiates by naltrexone diminished the placebo response, but that naltrexone may prolong ibuprofen analgesia by some unknown mechanism.

Adult↗

Multicenter, double-blind, multiple-dose, parallel-groups efficacy and safety trial of azelastine, chlorpheniramine, and placebo in the treatment of spring allergic rhinitis.

Azelastine, a novel antiallergic medication, was compared with chlorpheniramine maleate and placebo for efficacy and safety in the treatment of spring allergic rhinitis in a multicenter, double-blind, multiple-dose, parallel-groups study. One hundred fifty-five subjects participated. Subjects ranged in age from 18 to 60 years of age and had at least a 2-year history of spring allergic rhinitis, confirmed by positive skin test to spring aeroallergens. Medications were given four times daily; the azelastine groups received 0.5, 1.0, or 2.0 mg in the morning and evening with placebo in the early and late afternoon; the chlorpheniramine group received 4.0 mg four times daily. Daily subject symptom cards were completed during a screening period to assess pretreatment symptoms and during a 4-week treatment period while subjects received study medications. Individual symptoms, total symptoms, and major symptoms were compared to determine efficacy of medication. Elicited, volunteered, and observed adverse experiences were recorded for each subject and compared among groups. Vital signs, body weights, serum chemistry values, complete blood cell counts, urine studies, and electrocardiograms were obtained for each subject and compared among groups. Symptoms relief in the group receiving the highest concentration of azelastine (2.0 mg twice daily) was statistically greater than in the placebo group during all weeks of the study. Lower doses of azelastine were statistically more effective than placebo only during portions of the first 3 weeks of the study. In contrast, although the chlorpheniramine group did have fewer symptoms than the placebo group during the study, the difference never reached statistical significance during any week of the study. There were no serious side effects in any of the treatment groups. Drowsiness and altered taste perception were increased significantly over placebo only in the high-dose azelastine group. Azelastine appears to be a safe, efficacious medication for seasonal allergic rhinitis.

Adolescent↗

Levocabastine nasal spray better than sodium cromoglycate and placebo in the topical treatment of seasonal allergic rhinitis.

The efficacy and safety of the nasal administration (twice in each nostril, four times a day) of levocabastine (0.5 mg/ml) were compared with those of sodium cromoglycate (20 mg/ml) and placebo in a 2-week, parallel, double-blind trial in patients with seasonal allergic rhinitis. At the end of treatment, 89% of patients in the levocabastine-treated group rated their treatment as globally good or excellent as compared with 32% (p = 0.003) of sodium cromoglycate-treated and 35% (p = 0.002) of placebo-treated patients. According to the investigators' ratings, the severest nasal symptom and ocular complaints responded better to levocabastine than to cromoglycate (p = 0.05 and p = 0.03) or placebo treatment (p = 0.03 and p = 0.001). Visual analogue scale ratings in patients' diaries indicated that at the end of therapy, nasal symptoms were less severe in the levocabastine-treated group than in the sodium cromoglycate-treated (p = 0.03) or placebo-treated group (p = 0.001). Total symptom severity as a percentage of the theoretical maximum symptom severity during the treatment period was lower for levocabastine than for sodium cromoglycate (p = 0.06) or placebo (p = 0.004) for the severest nasal symptom (35% versus 47% and 76%), sneezing (the most frequent symptom) (27% versus 42% and 67%), and itchy nose (18% versus 37% and 67%). The percentage of days at which nasal symptoms were entirely absent was markedly higher in the levocabastine-treated (33%) than in the sodium cromoglycate-treated (9%; p = 0.006) or placebo-treated (3%; p = 0.001) group.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intranasal↗

Clinical evaluation of the efficacy and safety of noberastine, a new H1 antagonist, in seasonal allergic rhinitis: a placebo-controlled, dose-response study.

Noberastine (NOB), a new histamine H1 antagonist, has potent and specific peripheral antihistaminic activity. To evaluate the efficacy and safety of NOB in ragweed seasonal allergic rhinitis, 250 eligible patients were randomized to one of four parallel, double-blind treatment groups: NOB, 10, 20, and 30 mg, or placebo, each administered once daily for 3 weeks. Rescue medication was prohibited. Efficacy parameters included global response rate (percentage of responders), physician visit, patient-diary symptom scores, and onset of action. Efficacy analyses used alpha = 0.0167 (adjusted for multiple comparisons). Efficacy parameters demonstrated universal superiority of NOB therapy over placebo therapy with statistical significance achieved frequently; no statistically or clinically significant separation was demonstrated among NOB-treated groups. Global-response rates for all active-treatment groups (range, 62.7% to 71.1%) were statistically significantly greater than rates for the placebo-treated group (39.6%). Median time to first relief of symptoms was within 2 to 4 hours for NOB-treated groups versus 72 hours for the placebo-treated group. No significant abnormalities in safety parameters were ascribed to NOB treatment. Incidence and severity of adverse experiences of NOB-treated groups were comparable in incidence and severity to placebo treatment. NOB treatment did not appear to cause weight gain or sedation. Once-daily NOB, 10, 20, and 30 mg, is equally and highly effective and safe in the symptomatic management of seasonal allergic rhinitis compared to placebo.

Adolescent↗

Clinical features of depressed patients who do and do not improve with placebo.

The substantial placebo response in depression confounds treatment decisions and the assessment of new therapies. Improvement with placebo occurs infrequently in patients with chronic depression and in those with pituitary-adrenocortical hyperfunction, but other consistent predictors of placebo response have not been detected. We divided 241 moderately to severely depressed patients who had received placebo on a double-blind basis for 3 to 6 weeks into responders (greater than or equal to 50% improvement in Hamilton depression score, final Hamilton depression score less than or equal to 10), extreme nonresponders (less than 25% improvement), and partial responders (all others). Improvement with placebo was associated with a relatively short illness, a precipitating event, depression of only moderate global severity, and a good response to previous antidepressant treatment. These observations suggest that depressed patients who do and do not recover with placebo have different conditions that have not yet been fully characterized.

Adult↗

Metronidazole (Flagyl) and Arnica Montana in the prevention of post-surgical complications, a comparative placebo controlled clinical trial.

A double blind trial, was designed, in which 118 patients undergoing the removal of impacted wisdom teeth were randomly divided into the following groups; 41 patients received Metronidazole, 39 patients received Arnica Montana, 38 patients received the placebo. Metronidazole was more effective in pain control than Arnica (p less than 0.001) and placebo (p less than 0.01). It prevented swelling better than Arnica (p less than 0.01) and placebo (p less than 0.05) and was more effective in promoting healing than Arnica (p less than 0.01) and placebo (p greater than 0.02). Arnica Montana appeared to give rise to greater pain than placebo (p less than 0.05) and caused more swelling than the placebo (p less than 0.01).

Clinical Trials as Topic↗

Reduction of postoperative pain and swelling by ultrasound treatment: a placebo effect.

Ultrasound (US) therapy is used to reduce pain and inflammation and to accelerate healing after soft tissue injury. However, there is little objective evidence of its effectiveness and the mechanisms which may cause these effects are unknown. In a placebo-controlled double-blind clinical trial we examined the contribution of placebo and massage effects in ultrasound therapy following bilateral surgical extraction of lower third molars. Four to 6 h after surgery the patients (25 per group) received either no therapy, US (0.1 W/cm2), 'mock' US with massage, 'mock' US without massage, or 'self-massage' with a dummy applicator. Facial swelling, trismus, serum C-reactive protein, serum cortisol, pain and anxiety were measured 24 h postoperatively. The results showed that the beneficial analgesic and anti-inflammatory effects of US therapy were placebo-mediated, with maximum effect in the placebo ('mock' US) group without circular massaging with the applicator). Self-massage by the patient produced no significant effect. This placebo action was independent of changes in serum cortisol or patient anxiety state. US therapy can significantly reduce postoperative morbidity, but by placebo-mediated mechanisms which are unrelated to the US itself.

Adolescent↗