Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PLACEBOS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources

A randomized, double-blind, placebo-controlled, parallel-group study to assess the efficacy and safety of dual ACE/NEP inhibitor GW660511X in mild-to-moderate hypertensive patients.

This multicentre, double-blind, placebo-controlled, parallel-group study determined the efficacy and safety of GW660511 200 mg, a dual inhibitor of angiotensin-converting enzyme (ACE) and neutral endopeptidase (NEP), in mild-to-moderate hypertensive patients (diastolic blood pressure (DBP), > or =90 and < or =109 mm Hg; systolic blood pressure (SBP), > or =150 and < or =180 mm Hg). After a single-blind 2- to 4-week placebo run-in period, 123 patients (aged 18-65 years) were randomized to either placebo (n=62) or to active treatment (n=61) consisting of two consecutive 3-day dose titration periods of GW660511X 50 mg once daily and 100 mg once daily followed by GW660511X 200 mg once daily for 14 days. GW660511X 200 mg significantly lowered (baseline and placebo-corrected) both trough mean cuff SBP (-8.00 mm Hg, P=0.002) and DBP (-5.38 mm Hg, P=0.003). GW660511X 200 mg significantly reduced placebo-corrected mean 24-h and daytime but not night-time ambulatory SBP and DBP. Over the 0-24 h time period following GW660511X 200 mg, there were significant (P<0.001) reductions in serum ACE activity and significant (P<0.001) increases in plasma ANP concentration compared with placebo in terms of both peak and trough effects. In addition, treatment with GW660511X 200 mg significantly (P=0.003) increased (placebo-corrected, 1.52-fold) urinary excretion of cGMP over the 0-24 h interval. Treatment-related adverse events were experienced by 43% of the patients administered GW660511X 200 mg and 44% of those dosed with placebo with headache the most commonly reported. In conclusion, GW660511X 200 mg is an effective antihypertensive in mild-to-moderate hypertensive patients with potent effects on biological markers of ACE and NEP inhibition.

Adolescent↗

A placebo controlled crossover trial of liquid fluoxetine on repetitive behaviors in childhood and adolescent autism.

Repetitive behaviors are a core symptom domain in autism that has been linked to alterations in the serotonin system. While the selective serotonin-receptive inhibitor fluvoxamine has been shown to be effective in adults with autism, as yet no published placebo controlled trials with these agents document safety and efficacy in children with autism. This study examines the selective serotonin reuptake inhibitor liquid fluoxetine in the treatment of repetitive behaviors in childhood and adolescent autism spectrum disorders (ASDs). In total, 45 child or adolescent patients with ASD were randomized into two acute 8-week phases in a double-blind placebo-controlled crossover study of liquid fluoxetine. Study design included two randomized 8-week fluoxetine and placebo phases separated by a 4-week washout phase. Outcome measures included measures of repetitive behaviors and global improvement. Low-dose liquid fluoxetine (mean final dose: 9.9+/-4.35 mg/day) was superior to placebo in the treatment of repetitive behaviors by CY-BOCS compulsion scale. The effect size was in the moderate to large range, and the doses used were low. Liquid fluoxetine was only slightly, and not significantly, superior to placebo on CGI autism score partially due to a phase order effect. However, fluoxetine was marginally superior to placebo on a composite measure of global effectiveness. Liquid fluoxetine did not significantly differ from placebo on treatment emergent side effects. Liquid fluoxetine in low doses is more effective than placebo in the treatment of repetitive behaviors in childhood autism. Limitations include small sample size and the crossover design of the study. Further replication and long-term maintenance trials are needed.

Administration, Oral↗

Neurophysiologic correlates of side effects in normal subjects randomized to venlafaxine or placebo.

Adverse events reported in the context of medication administration may be due to pharmacodynamic and/or nonpharmacodynamic effects (eg, nocebo phenomena). Neurophysiological substrates of side effects may be examined in placebo-controlled antidepressant treatment trials. We explored the relationship between side effects and regional neurophysiologic changes in normal subjects receiving a 1-week placebo lead-in followed by 4 weeks randomized treatment with placebo (n = 15) or venlafaxine IR (n = 17). Quantitative electroencephalographic (QEEG) cordance measures were obtained before and during treatment, and side effects were assessed weekly using semistructured interviews. Side effect burden, characterized as the mean number of side effects per postrandomization visit, correlated significantly with neurophysiologic changes in the antidepressant group but not the placebo group. Medication group side effects were negatively correlated with changes in prefrontal cordance at end of placebo lead-in (r = -0.67, p < 0.003), at 2 weeks (r = -0.77, p < 0.002), and at 4 weeks (r = -0.77, p < 0.004) post randomization. After controlling for the prefrontal change at the end of placebo lead-in, postrandomization brain changes did not further explain side effect burden. Changes in prefrontal brain function associated with later antidepressant side effects were observed during placebo lead-in-prior to the administration of medication. Prefrontal brain function during brief placebo administration may help explain susceptibility to the development of antidepressant side effects. Results of these exploratory hypothesis-generating analyses should be considered tentative until replicated.

Adolescent↗

Rizatriptan 5 mg for the acute treatment of migraine in adolescents: a randomized, double-blind, placebo-controlled study.

OBJECTIVE: To investigate the tolerability and efficacy of rizatriptan 5 mg in adolescent migraineurs. METHODS: Randomized, double-blind, placebo-controlled study. Patients aged 12 to 17 years received rizatriptan 5 mg (n = 149) or placebo (n = 147) for a moderate or severe headache and for up to two recurrences. Headache severity, presence or absence of associated symptoms, and functional disability were assessed over a 4-hour postdose period, and any adverse events were recorded. The primary efficacy measure was pain-free status at 2 hours postdose. RESULTS: Rizatriptan 5 mg was well tolerated. The most commonly reported adverse events (all with incidence of 5% or less) among patients receiving rizatriptan were dry mouth, dizziness, asthenia/fatigue, nausea, and somnolence. The percentage of patients pain-free at 2 hours was 32% for rizatriptan 5 mg versus 28% for placebo (P=.474). The percentage of patients with pain relief (reduction of predose pain intensity to mild or none) at 2 hours was 66% for rizatriptan versus 56% for placebo (P=.079). Placebo response rates were higher than those typically observed in previous studies of rizatriptan in adults. Compared with placebo, rizatriptan significantly improved functional disability at 1.5 and 2 hours, and nausea at 1 and 1.5 hours. Post hoc analysis showed a significant benefit of rizatriptan versus placebo in the percentage of patients who had pain relief when their migraine attacks were treated on weekends (65% versus 36%, P=.046) compared with weekdays (66% versus 61%, P=.365), and the weekend placebo response rate was similar to that seen in adults. CONCLUSIONS: Rizatriptan 5 mg was well tolerated and effective on some measures when used in adolescents for the treatment of a migraine attack.

Adolescent↗

[Clinical double blind comparison of diclofensine and placebo in geriatric patients with depressive syndromes].

The objective of this double-blind trial was to assess the effect of diclofensine on geriatric patients with depressive syndromes in comparison to placebo. 40 patients (age 60-75 years) were treated for 3 weeks with a mean daily dose of 57.5 mg diclofensine or placebo. Diclofensine was found effective in 18 (= 90%) cases (placebo 60%) after 2.9 days on an average (placebo, 4.2 days), mostly having a mood elevating effect and in only 2 cases (placebo 1) having a stimulatory effect. The results of the global assessments, the Hamilton depression scale, the d2-test, the block design test and the mood scale (Befindlichkeitsskala) demonstrated a statistically significant superiority of diclofensine over placebo. The critical flicker frequency, on the other hand, was not able to differentiate significantly between the two drugs. The tolerance was considered as very good in all cases. Unwanted effects were observed in 13 patients (= 65%) of the diclofensine group and in 9 patients (= 45%) of the placebo group. They disappeared in most cases within one week after their appearance. According to this trial diclofensine can be described as a well tolerated drug without pronounced anticholinergic side effects, capable of improving depressive states faster and more effectively than placebo.

Aged↗

An oxytocin receptor antagonist (atosiban) in the treatment of preterm labor: a randomized, double-blind, placebo-controlled trial with tocolytic rescue.

OBJECTIVES: This study was designed to evaluate the efficacy and safety of the oxytocin receptor antagonist atosiban in the treatment of preterm labor. STUDY DESIGN: A multicenter, double-blind, placebo-controlled trial with tocolytic rescue was designed. Five hundred thirty-one patients were randomized to receive, and 501 received, either intravenous atosiban (n = 246) or placebo (n = 255), followed by subcutaneous maintenance with the assigned agent. Standard tocolytics as rescue tocolysis were permitted after 1 hour of either placebo or atosiban if preterm labor continued. The primary end point was the time from the start of study drug to delivery or therapeutic failure. Secondary end points were the proportion of patients who remained undelivered and did not receive an alternate tocolytic at 24 hours, 48 hours, and 7 days. RESULTS: No significant difference was found in the time from start of treatment to delivery or therapeutic failure between atosiban and placebo (median, 25.6 days vs 21.0 days, respectively; P =.6). The percentages of patients remaining undelivered and not requiring an alternate tocolytic at 24 hours, 48 hours, and 7 days were significantly higher in the atosiban group than in the control group (all P < or =.008). A significant treatment-by-gestational age interaction existed for the 48-hour and 7-day end points. Atosiban was consistently superior to placebo at a gestational age of > or =28 weeks. Fourteen atosiban-treated patients and 5 placebo-treated patients were randomized at <24 weeks; the incidence of fetal-infant deaths was higher for the atosiban group at <24 weeks. Maternal-fetal adverse events were similar except for injection-site reactions, which occurred more often with atosiban. CONCLUSIONS: In this trial the treatment of patients in preterm labor with atosiban resulted in prolongation of pregnancy for up to 7 days for those at a gestational age > or =28 weeks, and this occurred with a low rate of maternal-fetal adverse effects. In addition, at a gestational age > or =28 weeks, the infant morbidity and mortality of atosiban-initiated standard care were similar to those with placebo-initiated standard care. Given that all patients in this study were eligible for tocolysis and that, in practice, nearly all patients who are eligible for a tocolytic receive one, the benefit of using atosiban is the placebo-like maternal-fetal side effect profile. These observations support the use of this oxytocin receptor antagonist in the treatment of patients in preterm labor with intact membranes. Efficacy and infant outcome data at <28 weeks are inconclusive.

Double-Blind Method↗

Artesunate and praziquantel for the treatment of Schistosoma haematobium infections: a double-blind, randomized, placebo-controlled study.

Recently, artemisinin derivatives have been shown to be efficacious in chemoprophylaxis of and chemotherapy for Schistosoma japonicum and S. mansoni infections. Therefore, a double-blind, randomized, placebo-controlled study was carried out to investigate the efficacy and tolerability of artesunate plus placebo and the combination of artesunate and praziquantel in the treatment of S. haematobium infections in Gabon. The 300 infected schoolchildren included in the study were randomized to receive artesunate plus placebo (n=90), praziquantel plus placebo (n=90), artesunate and praziquantel (n=90), or only placebo (n=30). End points were efficacy, assessed as cure on day 56, and tolerability. All treatment regimens were well tolerated. The praziquantel plus placebo-treated group attained a cure rate of 73%, artesunate plus placebo a rate of 27%, the combination of artesunate and praziquantel a rate of 81%, and placebo alone a rate of 20%. In summary, earlier findings of efficacy of artemisinin derivitives against S. mansoni and S. japonicum could not be confirmed in S. haematobium infections.

Animals↗

A pilot study to assess the effect of three short-term treatments on frequent and/or prolonged bleeding compared to placebo in women using Implanon.

BACKGROUND: The major side-effect of progestogen-only contraception is disruption of menstrual bleeding patterns, which can lead to a high incidence of early discontinuation. The aim of this study was to compare three treatments with placebo on the duration and recurrence of frequent and/or prolonged bleeding in Implanon users. METHOD: Women between the ages of 18 and 45 years, who had used Implanon for > or =3 months and were experiencing prolonged or frequent bleeding patterns, were recruited at four Australian sites. Subjects were randomized to treatment using computer-generated random number table if they met the World Health Organization criteria for prolonged and/or frequent bleeding in the previous 90 days [Belsey, E.M., Pinol, A.P.Y. and Taskforce on Long-Acting Systemic Agents for Fertility Regulation, World Health Organization (1997) Contraception 55,57-65]. Treatments were: (1) mifepristone 25 mg given twice on day 1 followed by 4 days of twice daily placebo; (2) mifepristone 25 mg given twice on day 1 followed by 4 days of ethinyl estradiol (EE) 20 microg in the morning and placebo at night; (3) doxycycline 100 mg twice daily for 5 days; and (4) placebo twice daily for 5 days. Analysis was by intention to treat. The primary endpoint was the number of days of bleeding and spotting immediately following initiation of the 5 day course of each active therapy compared with placebo. RESULTS: A total of 179 women was assigned to treatment. Both mifepristone in combination with EE and doxycycline alone were significantly more effective in stopping an episode of bleeding {mean 4. 3 days [confidence interval (CI) 3.5-5.2], and 4.8 days (CI 3.9-5.8) respectively} than mifepristone alone or placebo [5.9 days (CI 4.8-7.2) and 7.5 days (CI 6.1-9.1) respectively]. No effect on subsequent bleeding patterns was observed in any treatment group. CONCLUSION: Both mifepristone plus EE and doxycycline alone were significantly more effective than placebo in terminating an episode of bleeding in women with prolonged and/or frequent bleeding using Implanon. We believe that the observed reduction in the number of bleeding days by almost 50% compared to placebo in both the mifepristone combination group and the doxycycline group demonstrates a clinically significant improvement in bleeding patterns and that further trials are needed to compare different combinations of therapy as well as multiple dosing regimens in order to establish which is the most effective treatment option. The effect of repeat administration or combinations of these preparations on long-term bleeding patterns requires further investigation.

Adolescent↗

Treatment with the GnRH antagonist ganirelix prevents premature LH rises and luteinization in stimulated intrauterine insemination: results of a double-blind, placebo-controlled, multicentre trial.

BACKGROUND: This study was designed to assess whether the use of ganirelix in women undergoing stimulated IUI could prevent the occurrence of premature LH rises and luteinization (LH+progesterone rises). METHODS: Women of infertile couples, diagnosed with unexplained or male factor infertility, were randomized to receive either ganirelix (n=103) or placebo (n=100) in a double-blind design. All women were treated with an individualized, low-dose rFSH regimen started on day 2-3 of cycle. Ganirelix (0.25 mg/day) was started if one or more follicles>or=14 mm were visualized. Ovulation was triggered by HCG injection when at least one follicle>or=18 mm was observed and a single IUI was performed 34-42 h later. The primary efficacy outcome was the incidence of premature LH rises (+/-progesterone rise). RESULTS: In the ganirelix group, four subjects had a premature LH rise (value>or=10 IU/l), one LH rise prior to the start of ganirelix and three LH rises during ganirelix treatment, whereas in the placebo group 28 subjects had a premature LH rise, six subjects prior to the start of placebo and 22 subjects during placebo treatment. The incidence of LH rises was significantly lower in ganirelix cycles compared to placebo cycles (3.9 versus 28.0%; P=0.003 for ITT analysis). When excluding subjects with an LH value>or=10 IU/l before the start of ganirelix/placebo the incidence of LH rises was also significantly lower in ganirelix cycles compared to placebo cycles (2.9 versus 23.4%; P=0.003 for ITT analysis). Premature luteinization (LH rise with concomitant progesterone rise>or=1 ng/ml) was observed in one subject in the ganirelix group and in 17 subjects in the placebo group of which three subjects had a premature spontaneous ovulation. Ongoing pregnancy rates per attempt were 12.6 and 12.0% for the ganirelix and placebo groups respectively. CONCLUSIONS: Treatment with ganirelix effectively prevents premature LH rises, luteinization in subjects undergoing stimulated IUI. Low-dose rFSH regimen combined with a GnRH antagonist may be an alternative treatment option for subjects with previous proven luteinization or in subjects who would otherwise require insemination when staff are not working.

Adolescent↗

Randomized, double-blinded, placebo-controlled intervention study with supplemental calcium in families with hereditary nonpolyposis colorectal cancer.

BACKGROUND: A high-fat diet has been recognized for some time as a major risk factor for colorectal cancer. It is thought that fat promotes this disease by increasing the levels of fatty and bile acids within the colon. These acids irritate and damage the epithelial cells of the colon. As a result of this cellular destruction, an increase in the rate of cellular proliferation occurs. Oral calcium supplementation has been proposed as a dietary intervention for individuals at high risk of colorectal cancer because of its ability to reduce rectal epithelial cell proliferation through the binding of fatty and bile acids. Placebo-controlled studies, however, have yielded varying results. PURPOSE: We conducted a randomized, double-blinded, placebo-controlled trial to test oral calcium supplementation in patients at high risk of developing hereditary nonpolyposis colorectal cancer. METHODS: Thirty subjects at risk for this cancer, with an increased epithelial cell proliferation along the colon and rectum, were randomly assigned to either a placebo group (n = 15) or a treatment group (n = 15). They received either oral calcium carbonate (CaCO3) supplements (1.5 g) or placebo (cellulose and starch) three times a day during a 12-week period. Colonic biopsy specimens (rectal, sigmoidal, and descending) were obtained prior to and after the intervention trial, during endoscopy, for determination of labeling index (LI) of whole crypts and crypt compartments by 5-bromo-2'-deoxyuridine incorporation and immunohistochemistry. Proportional bile acid compositions in duodenal bile and cytolytic activity of fecal water were also determined. All P values represent two-tailed tests of statistical significance. RESULTS: Statistically significant reductions, comparing before with after intervention, in rectal whole-crypt LI after receiving either calcium supplements (from 10.9% +/- 5.2% [mean +/- SD] to 6.2% +/- 1.5%; P < .02) or placebo (from 11.7% +/- 4.7% to 8.2% +/- 3.1%; P < .05) were observed. In the three bowel segments, no statistically significant differences were observed between the supplemental calcium and placebo groups. A statistically significant reduction in cytolytic activity was determined during calcium supplementation (from 57% +/- 41% to 32% +/- 30%; P < .05), whereas in the placebo group, it did not change (from 42% +/- 41% to 36% +/- 27%; P > .10). CONCLUSIONS: Oral calcium supplementation was shown to cause only a minor nonstatistically significant reduction of epithelial cell proliferation in the rectum, compared with placebo, and to have no effect on the same parameter in the sigmoid and descending colon in first-degree relatives of hereditary nonpolyposis colorectal cancer patients. IMPLICATION: These results cast doubt on the value of calcium supplementation in the prevention of colorectal cancer, especially in individuals already consuming an adequate amount of dietary calcium.

Adolescent↗

Double-blind, placebo-controlled study with reboxetine in inpatients with severe major depressive disorder.

The efficacy and tolerability of reboxetine, a unique selective noradrenaline reuptake inhibitor, were compared with those of placebo in a 6-week, randomized, double-blind study of hospitalized patients with a DSM-III-R diagnosis of major depressive disorder. Fifty-two patients (25 in the placebo group, 27 in the reboxetine group) were included in the efficacy analysis. Sixteen (64%) of those in the placebo group and four (15%) in the reboxetine group were withdrawn during the study because of lack of efficacy. Improvement in the mean Hamilton Rating Scale for Depression (HAM-D) total score at last assessment was significantly greater in the reboxetine group than in the placebo group (p < 0.001). Similarly, the response rate to treatment, defined as > or =50% reduction in HAM-D total score, was 74% for patients who received reboxetine compared with 20% for those who received placebo (p < 0.001). A significantly greater response with reboxetine than with placebo was seen as early as day 10 of treatment (p = 0.006). The therapeutic efficacy of reboxetine was substantiated by improvement in mean scores on the Zung Self-Rating Scale and on the Clinical Global Impression Severity of Illness and Global Improvement scales. Reboxetine was well tolerated, and only one patient in each group withdrew because of adverse events. Dry mouth, insomnia, blurred vision, sweating, and constipation were recorded more frequently in the reboxetine group than in the placebo group. There was a tendency toward orthostatic changes in the systolic blood pressure, but this was not clinically significant. This study demonstrated that reboxetine is significantly more effective than placebo in the treatment of hospitalized patients with severe major depressive disorder and is well tolerated.

Adolescent↗

A double-blind, placebo-controlled study comparing mianserin and amitriptyline in moderately depressed outpatients.

We report on the results of a study comparing mianserin with amitriptyline and placebo, in outpatients with major depression (DSM-III 296.2 or 296.3). One hundred and forty-nine patients were randomized to mianserin (n = 50), amitriptyline (n = 50) or placebo (n = 49). Medication was taken in a nightly (qhs) dose. During Week 1, the maximum dose was 60 mg mianserin, 120 mg amitriptyline or two placebo capsules. Beginning at Day 7 (through Day 42) maximum dosages were 150 mg mianserin, 300 mg amitriptyline or five placebo capsules. At multiple weeks and endpoint, statistically significant reductions in the Hamilton Depression Scale (HAM-D) 17- and 21-item scores were recorded for both active drugs compared with placebo. Positive results with the HAM-D were corroborated by other measures of efficacy. There were no statistically significant differences between mianserin and amitriptyline in terms of efficacy; however, the results do suggest a more rapid therapeutic response for mianserin compared with amitriptyline, in terms of percentage of patients showing > or = 50% improvement at Weeks 2 (30% vs 23%) and 4 (61% vs 44%). The most common adverse experiences were somnolence (amitriptyline and mianserin 60%, placebo 31%) and dry mouth (amitriptyline 76%, mianserin 30% and placebo 20%). Our results indicate that mianserin is clearly superior to placebo, compares favorably with amitriptyline, and is a safe, well-tolerated, effective medication in the treatment of depressed outpatients.

Adult↗

Citalopram 20 mg, 40 mg and 60 mg are all effective and well tolerated compared with placebo in obsessive-compulsive disorder.

Serotonin reuptake inhibitors appear to be uniquely effective treatments for obsessive-compulsive disorder (OCD). This double-blind, placebo-controlled study was the first trial to assess the efficacy of the most selective of the serotonin reuptake inhibitors, citalopram, in OCD. A total of 401 patients were randomized to receive citalopram 20, 40 or 60 mg/day or placebo for 12 weeks. All three doses of citalopram were significantly more effective than placebo measured on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) change score (P < 0.01). The highest response rate, defined as 25% improvement in Y-BOCS entry score, was observed in the 60 mg group (65%). This compared with 52% and 57.4% in the 40 mg and 20 mg groups. Response rate on placebo was 36.6% (P < 0.05 for all three doses of citalopram compared to placebo). There was no significant difference between the individual doses of citalopram. An advantage was seen for citalopram on the Sheehan Disability Scale compared with placebo (P < 0.05 on all three citalopram groups versus placebo for both the work situation and the family life and home responsibilities and P < 0.05 on citalopram 60 mg and 20 mg versus placebo for the social life and home activities). Citalopram was well tolerated; only 4 to 6 patients in each dose group discontinued the study prematurely due to adverse events.

Activities of Daily Living↗

Escitalopram 10 mg/day is effective and well tolerated in a placebo-controlled study in depression in primary care.

Escitalopram, a selective serotonin reuptake inhibitor (SSRI), was compared to placebo in a study of patients with major depressive disorder (DSM-IV) who had baseline Montgomery-Asberg Depression Rating Scale (MADRS) total scores >or=22 and <or=40. After a 1-week, single-blind placebo period, patients were randomized to receive escitalopram 10 mg/day (n=191) or placebo (n=189) in an 8-week, double-blind period. The primary efficacy analysis of adjusted mean change in MADRS total score from baseline showed a statistically significantly larger effect for escitalopram than for placebo with a treatment difference at week 8 (last observation carried forward, LOCF) of 2.7 points (SE 0.85; P=0.002). In further by-week efficacy analyses, the effect of escitalopram was consistently larger than that of placebo (P<0.05) beginning at week 1 (Clinical Global Impression-Improvement score), week 2 (MADRS score) or week 3 (Clinical Global Impression-Severity score). Escitalopram was very well tolerated with a low overall withdrawal rate similar to that for placebo. Nausea was the only adverse event reported significantly more in escitalopram-treated patients than in placebo-treated patients, although it was infrequent and transient. Escitalopram 10 mg/day had a statistically significantly better antidepressant effect than placebo as early as week 1, and was safe and very well tolerated.

Administration, Oral↗

The ethics of using placebo in hypertension clinical trials.

USE OF PLACEBO CONTROLS: Placebo controls can enhance the value of two types of hypertension trials: measurement of the blood pressure-lowering efficacy of antihypertensive treatment and determination of whether therapeutic interventions can affect clinical endpoints. However, the possibility of adverse outcomes in hypertensive patients allocated to placebo therapy raises ethical concerns. EFFICACY STUDIES: Placebo controls in efficacy studies are particularly helpful in thoroughly quantifying the effect of treatment. The hazard to patients can be minimized by exposing them to placebo for the least possible amount of time and, assuming that blood pressure is itself the primary variable, reducing the probability of cardiovascular events by excluding subjects with severe hypertension or major concomitant risk factors. ENDPOINT STUDIES: Endpoint studies present a more difficult challenge, for they are designed in anticipation of cardiovascular events and patients at high risk are often enrolled in order to more rapidly achieve the required number of endpoints for statistical analysis. In such circumstances, positive therapeutic controls, despite the complexities of analysis, must be preferred to placebo. EARLY-STAGE HYPERTENSION: Important questions regarding the management of early-stage hypertension remain, and despite official treatment guidelines recommendations, currently based chiefly on extrapolation and judgement, many physicians routinely withhold therapy in mild hypertension, even when other risk factors are present. With appropriate safeguards, placebo-controlled trials may be necessary to examine potential benefits of therapy in such patients. Indeed, resolving therapeutic uncertainty and creating well founded recommendations for the future management of the many patients with milder forms of hypertension can make placebo controls both ethical and appropriate.

Blood Pressure↗

Usefulness of home blood pressure measurements in assessing the effect of treatment in a single-blind placebo-controlled open trial.

OBJECTIVES: Reproducibility of home blood pressure measurements (HBP), and the placebo effect on HBP, were examined to establish the number of subjects required in order to observe a significant antihypertensive effect of a drug for a comparative study between placebo and active treatment. METHODS: Reproducibility of HBP (n = 172 for systolic blood pressure and n = 137 for diastolic blood pressure) and the placebo effect on HBP (n = 35 for systolic and n = 42 for diastolic blood pressure) were examined using a semi-automatic electronic device on untreated hypertensive subjects during 21 consecutive days of measurements. From these two studies, the number of subjects required in order to observe a significant antihypertensive drug effect was assessed. In both studies, measurements from the first 3 days were excluded from the analysis. RESULTS: Reproducibility, defined as the difference between the initial 5 day average (days 4-8) and the last 5 day average (days 17-21) was -1.9 +/- 7.0/-1.4 +/- 4.8 mmHg (mean +/- SD), indicating high reproducibility with a minimal regression to the mean effect. A placebo was administered after the 8 day run-in period. The difference between the initial 5 day average (days 4-8) and the last 5 day average (days 17-21) was compared. The mean difference was 1.1 +/- 6.2/0.2 +/- 5.7 mmHg, suggesting that there was a minimal, if any, placebo effect. As determined by the power calculations, based on the standard deviations of the tests for reproducibility and the placebo effect, nine of 13 subjects are required to show that a 9/5 mmHg decrease in systolic HBP/diastolic HBP (50% of estimated effective decrease in systolic HBP/diastolic HBP according to the guidelines for clinical trials in Japan) is statistically significant CONCLUSIONS: The results suggest that the HBP measurement is highly reproducible and that there is a minimal, if any, placebo effect. These characteristics of HBP contribute to minimizing the number of subjects necessary for assessment of antihypertensive drug effects in comparative studies between an active treatment and placebo.

Adult↗

A placebo-controlled, randomized withdrawal study of sertraline for panic disorder in Japan.

The objective of this double-blind, placebo-controlled randomized withdrawal study was to evaluate the efficacy and safety of sertraline for 8 weeks in treating Japanese patients with DSM-IV panic disorder. Patients (n=394) were initially treated with 8 weeks of open-label sertraline followed by 8 weeks of double-blind treatment with either sertraline (50-100 mg/day) or placebo. Responders during the open-label phase were eligible to be entered into the double-blind phase. Two hundred and forty patients were entered to the double-blind phase and randomly assigned to receive sertraline (n=119) or placebo (n=121). On the primary efficacy measure (relapse), there was no significant difference between the two treatment groups (sertraline 10.1%; placebo 13.2%). However, the frequency of panic attacks was significantly (P=0.012) lower for sertraline compared to placebo. The proportion of sertraline-treated patients who met response criteria (Clinical Global Impression-Improvement Scale score of 1 or 2) at the end of double-blind phase treatment was also significantly (P=0.003) higher for sertraline (89.9%) compared to placebo (74.4%). Panic Disorder Severity Scale total score was significantly (P=0.012) lower in the sertraline group compared to the placebo group. Adverse events during acute treatment were consistent with the known adverse event profile of sertraline, and the incidence of adverse events during the double-blind phase treatment was not different between sertraline and placebo.

Adult↗

Randomized, double-blind, placebo-controlled, crossover study of sertraline (Zoloft) for the treatment of hot flashes in women with early stage breast cancer taking tamoxifen.

We observed the relief of hot flashes in breast cancer survivors taking tamoxifen and treated with sertraline for depression. Our objective was to assess the effect of sertraline on the frequency and severity of hot flashes, mood status, and health-related quality of life. We used a randomized, double-blind, placebo-controlled, crossover study using 6 weeks of sertraline (50 mg each morning) versus placebo. Study participants were 62 breast cancer survivors from an oncology clinic in a tertiary care center on adjuvant tamoxifen reporting bothersome hot flashes. Patients were asked to keep a daily hot flash diary to record hot flash frequency and severity, from which hot flash scores (frequency x severity) were calculated. The Center for Epidemiologic Studies depression scale and Functional Assessment of Cancer Therapy--Breast (FACT-B) (at baseline, 6 weeks, and 12 weeks) were used to assess mood and quality of life. Sixty-two women were accrued. Forty-seven women (median age 53.9 years, range 36.6-77.1 years; 89% postmenopausal; 85.5% Caucasian) completed the first 6 weeks and 39 completed 12 weeks. The baseline daily hot flash frequency and score were 5.8 (standard deviation 4.1) and 11.5 (14.0), respectively. At the end of the first 6 weeks, hot flash frequency decreased by 50% in 36% of those taking sertraline compared to 27% taking placebo. In the crossover analysis, sertraline was significantly more effective than placebo: women crossing from placebo to sertraline had a decrease (-0.9 and -1.7) in hot flash frequency and score, whereas those crossing from sertraline to placebo had an increase (1.5 and 3.4) in hot flash frequency and score (p = 0.03 and 0.03). Forty-eight percent preferred the sertraline period, 11% preferred the placebo period, and 41% had no preference (p = 0.006). Measures of depression and quality of life were within normal range and did not change significantly within treatment groups. Sertraline decreases hot flashes in breast cancer survivors taking tamoxifen and women prefer sertraline to placebo. Further study of sertraline for the management of hot flashes is warranted.

Adult↗