Biomedical subjects

Charles M Beasley

Publications and source records attributed to Charles M Beasley.

16 recordsLinked to original sources

PubMed2007

Treatment-associated suicidal ideation and adverse effects in an open, multicenter trial of fluoxetine for major depressive episodes.

BACKGROUND: Some reports suggest that a subset of depressed patients may experience suicidality - that is increase or emergence of suicidal ideation (SI) or behavior--after initiation of an antidepressant. The time course and clinical correlates of this phenomenon have not been characterized in detail. METHOD: We conducted a secondary analysis of a multicenter, prospective, open, 12-week trial of fluoxetine 20 mg in outpatients with nonpsychotic major depressive episodes. Adverse effects and other clinical features associated with the emergence of suicidality, defined using item 3 of the Hamilton Depression Rating Scale, were examined using Cox regression models. RESULTS: Among 414 subjects without SI at baseline, 59 (14.3%) reported SI on at least 1 postbaseline visit. In a Cox regression, emergence of activation and worsening of depression severity were independently associated with emergence of SI, along with female gender, younger age and having thoughts that life was not worth living prior to treatment. Treatment response and remission were significantly less likely among subjects who developed SI. CONCLUSIONS: New SI was relatively common in this trial of fluoxetine and associated with the emergence of activation and overall symptomatic worsening. Whether prophylaxis against or aggressive treatment of adverse events can decrease emergence of SI merits further study.

Adolescent↗

PubMed2006

Effects of antipsychotic drugs on I(to), I (Na), I (sus), I (K1), and hERG: QT prolongation, structure activity relationship, and network analysis.

PURPOSE: To evaluate in vitro and computationally model the effects of selected antipsychotic drugs on several ionic currents that contribute to changes in the action potential in cardiac tissue. METHODS: Fourteen antipsychotic drugs or metabolites were examined to determine whether QT interval prolongation could be accounted for by an effect on one or more myocardial ion channels [I(to), I(Na), I(sus), I(K1), and human ether-a-go-go related gene (hERG)]. Using the patch clamp technique, drug effects on these human cardiac currents were tested. RESULTS: All molecules had little inhibitory effect on ion channels (blocking at concentrations >5 microM) other than hERG. A significant correlation was observed between the estimated hERG blockade and the increase in corrected QT for five of the antipsychotics. Molecular modeling identified hydrophobic features related to the interaction with hERG and correctly rank-ordered the test set molecules olanzapine and its metabolites. A network analysis of ligand and protein interactions around hERG using MetaCore (GeneGo Inc., St. Joseph, MI, USA) was used to visualize antipsychotics with affinity for this channel and their interactions with other proteins in this database. CONCLUSION: The antipsychotics do not inhibit the ion channels I(to), I(Na), I(sus), I(K1) to any appreciable extent; however, blockade of hERG is a likely mechanism for the prolongation of the QT interval.

Action Potentials↗

PubMed2006

Is quality of life among minimally symptomatic patients with schizophrenia better following withdrawal or continuation of antipsychotic treatment?

This secondary report from our 52-week, double-blind, relapse prevention trial tested whether stable patients with schizophrenia who were taken off active drug treatment would experience greater improvements in long-term quality of life than those who were continued on antipsychotic treatment. On average, Heinrichs-Carpenter Quality-of-Life Scale total scores improved by 4.3 +/- 10.6 points during treatment with olanzapine (10-20 mg/d; n = 212), but decreased by 7.1 +/- 14.6 points during treatment with placebo (n = 92; P < 0.001). Mean Quality-of-Life Scale total scores worsened in both treatment groups for the relapsing patient subgroup, whereas for nonrelapsing patients, those treated with olanzapine had significantly improved mean Quality-of-Life Scale total scores compared with those given placebo. For a subset of nonrelapsing patients who were considered "nonexacerbating" on the basis of minimal non-clinically relevant increases in psychopathology, Quality-of-Life Scale total mean change was no better (P = 0.066) for those given placebo (2.7 +/- 11.0; n = 40) than those treated with olanzapine (5.7 +/- 8.9; n = 174). Path analysis indicated a direct effect of treatment (approximately 29%) on quality of life that was not accounted for by differential changes in psychopathology. In conclusion, stable patients with schizophrenia who were taken off active drug treatment experienced no greater improvements in long-term quality of life than those who were continued on antipsychotic treatment, even in the absence of psychotic symptoms.

Adolescent↗

PubMed2005

The combined use of ibutilide as an active control with intensive electrocardiographic sampling and signal averaging as a sensitive method to assess the effects of tadalafil on the human QT interval.

OBJECTIVES: This study was designed to evaluate effects of tadalafil, a phosphodiesterase-5 inhibitor used for the treatment of erectile dysfunction (ED), on the QT interval. BACKGROUND: Cardiovascular disease is common in men with ED. Men with cardiovascular disease and ED may have decreased cardiac repolarization reserve. METHODS: Effects of tadalafil (100 mg by mouth), ibutilide (0.002 mg/kg intravenously), and placebo on the QT interval in healthy men were compared (placebo and tadalafil [n = 90], with a subset [n = 61] receiving all treatments; mean age 30 years, range 18 to 53 years). Electrocardiographic sampling was done for two days before treatment and on treatment days. The QT was corrected for RR interval with five correction methods, including an individual correction (QTcI). Plasma concentrations of tadalafil were measured to evaluate concentration-QT effect relationships. RESULTS: At the time corresponding to maximum plasma concentration of tadalafil, the mean difference in the change in QTcI between tadalafil and placebo was 2.8 ms; tadalafil was equivalent to placebo (a priori, upper limit of 90% confidence interval < 10 ms [actual = 4.4 ms]; post hoc, upper limit of 95% confidence interval < 5 ms [actual = 4.8]). The active control, ibutilide, significantly increased QTcI by 6.9 and 8.9 ms compared with tadalafil and placebo, respectively. Similar statistical results were obtained with four additional QT correction methods. No subject had a QTcI > or = 450 ms or an increase in QTcI > or = 30 ms with any treatment. CONCLUSIONS: Based on the a priori statistical test of equivalence, placebo and high-dose tadalafil produced equivalent effects on the QT interval. This study reliably discerned 5- to 10-ms changes in corrected QT in the ibutilide active control group.

Adolescent↗

PubMed2005

Efficacy and safety of oral tadalafil in the treatment of men in Canada with erectile dysfunction: a randomized, double-blind, parallel, placebo-controlled clinical trial.

INTRODUCTION: Erectile dysfunction (ED) is a highly prevalent, often undertreated condition. AIM: This 12-week, double-blind, parallel, placebo-controlled study was conducted at 25 sites in Canada to evaluate the efficacy and safety of oral tadalafil, a phosphodiesterase type 5 inhibitor, for the treatment of ED. METHODS: Men with ED of organic, psychogenic, or mixed etiology were stratified by baseline ED severity then randomly assigned to placebo (N = 50), tadalafil 10 mg (N = 103), or tadalafil 20 mg (N = 100), taken as needed (maximum, once daily). MAIN OUTCOME MEASURES: Efficacy was assessed by the International Index of Erectile Function (IIEF), a Sexual Encounter Profile diary, and a global assessment question (GAQ). RESULTS: Tadalafil 10 mg and tadalafil 20 mg significantly improved erectile function compared with placebo (P < 0.001, all measures). At end point, the mean IIEF erectile function (EF) domain scores were 14.5, 21.2, and 23.3 of a possible score of 30 for placebo, tadalafil 10 mg, and tadalafil 20 mg, respectively. Patients treated with tadalafil reported greater change from baseline on the IIEF EF domain score compared with placebo, regardless of baseline ED severity. During treatment, the mean per-patient proportion of successful intercourse attempts was higher for tadalafil 10 mg and 20 mg than for placebo (placebo, 31.9%; tadalafil 10 mg, 56.7%; and tadalafil 20 mg, 61.5%), and a greater proportion of patients reported improved erections with tadalafil (GAQ; placebo, 22.0%; tadalafil 10 mg, 67.0%; tadalafil 20 mg, 79.0%). Fifty percent and 62% of patients treated with tadalafil 10 mg and 20 mg, respectively, achieved successful sexual intercourse after their first dose, compared with 31% with placebo. Treatment-emergent adverse events were generally mild or moderate. CONCLUSION: Tadalafil was an effective, well-tolerated therapy for ED of broad-spectrum etiology and severity.

3',5'-Cyclic-GMP Phosphodiesterases↗

PubMed2004

Absence of clinically important HERG channel blockade by three compounds that inhibit phosphodiesterase 5--sildenafil, tadalafil, and vardenafil.

Compounds that inhibit phosphodiesterase 5 (PDE5) have been developed for the treatment of erectile dysfunction. Because men with erectile dysfunction frequently have comorbid cardiovascular disease, they may have limited cardiac repolarization reserve and be at risk of arrhythmia if treated with medications that prolong ventricular repolarization. The human ether-a-go-go related gene (HERG) channel is important for repolarization in human myocardium and is a common target for drugs that prolong the QT interval. We studied the ability of three compounds that inhibit PDE5--sildenafil, tadalafil, and vardenafil--to block the HERG channel. Using a whole cell variant of the patch-clamp method, the HERG current was measured in a stably transfected human embryonic kidney cell line expressing the HERG channel. The compounds produced dose-dependent reductions in HERG current amplitude over a concentration range of 0.1 to 100 microM. The IC50 values were 12.8 microM for vardenafil and 33.3 microM for sildenafil. Because the maximum soluble concentration of tadalafil (100 microM) produced only a 50.9% inhibition of the HERG current amplitude, the IC50 value for tadalafil could not be determined with the Hill equation. Tadalafil had the weakest capacity to block the HERG channel, producing a 50.9% blockade at the maximum soluble concentration (100 microM), compared with 86.2% for vardenafil (100 microM) and 75.2% for sildenafil (100 microM). In conclusion, the concentrations of the PDE5 inhibitors required to evoke a 50% inhibition of the HERG current were well above reported therapeutic plasma concentrations of free and total compound. None of the three compounds was a potent blocker of the HERG channel.

3',5'-Cyclic-GMP Phosphodiesterases↗

PubMed2004

A multicenter, randomized, double-blind, crossover study to evaluate patient preference between tadalafil and sildenafil.

PURPOSE: To assess patient preference for erectile dysfunction treatment between either sildenafil or tadalafil, each administered with their respective dosing instructions, and to evaluate preference for either sildenafil or tadalafil dosing instructions during tadalafil therapy. METHODS: We conducted a randomized, double-blind, crossover study consisting of four treatment arms. Because the dosing instructions for sildenafil and tadalafil are different, a unique methodology using sham placebo arms was employed to maintain the blind. To assess drug preference, 219 patients were randomized to either sildenafil 50 mg or tadalafil 20 mg, with dosing instructions reflecting their respective product profiles. To assess dosing instruction preference during tadalafil therapy, 46 patients were randomized to tadalafil 20 mg with either tadalafil or sildenafil dosing instructions. After 12 weeks, patients were crossed-over. After 4 weeks of each treatment, all patients following sildenafil dosing instructions were offered the opportunity for an upward dose titration. In a double-blind fashion, all patients who requested an upward titration received additional capsules. To mimic the pattern of dose usage observed in clinical practice, the number of patients who received additional double-blind active medication was limited to 35% of patients taking sildenafil in each treatment period in each country. Following the crossover treatment period, patients chose their preferred double-blind treatment with dosing instructions to receive in the 12-week extension period. RESULTS: In the drug preference assessment, 132 of 181 (73%) evaluable patients chose to receive tadalafil (p < 0.001) during the extension period. In the dosing instruction preference assessment, 24 of 36 (67%) evaluable patients preferred tadalafil with tadalafil dosing instructions (p = 0.046). Sildenafil and tadalafil were well tolerated. CONCLUSIONS: In the doses utilized in this study, 73% of patients preferred tadalafil with tadalafil dosing instructions for the treatment of their erectile dysfunction over sildenafil with sildenafil dosing instructions. During tadalafil therapy, 67% of patients preferred tadalafil dosing instructions over sildenafil dosing instructions.

Adult↗

PubMed2003

Effects of intramuscular olanzapine vs. haloperidol and placebo on QTc intervals in acutely agitated patients.

Prolongation of the QTc interval has been reported during treatment with oral antipsychotic agents and may be more pronounced during parenteral administration. Pooled QTc interval data from acutely agitated patients across four double-blind trials were compared. Databases included: placebo-controlled [two schizophrenia, one bipolar mania trials (n=565)]; haloperidol-controlled [two schizophrenia trials (n=482)]; geriatric placebo-controlled [1 dementia trial (n=204)]. Patients received 1-3 injections of intramuscular (IM) olanzapine (2.5-10 mg/injection), IM haloperidol (7.5 mg/injection), or IM placebo. At 2 and 24 h after IM olanzapine treatment, the mean QTc interval decreased approximately 3 ms from baseline in the placebo- and haloperidol-controlled databases. When there was a statistically significant difference between IM olanzapine and IM placebo, QTc intervals decreased during treatment with IM olanzapine and increased with IM placebo. The incidences of prolonged (endpoint >/=99th percentile of healthy adults or >/=500 ms) or lengthened (increase >/=60 ms) QTc intervals during treatment with IM olanzapine (<3% placebo- and haloperidol-controlled databases, <12% geriatric placebo-controlled database) were never significantly greater than with comparators. These data suggest that IM olanzapine has a favorable QTc interval profile in acutely agitated patients with schizophrenia, bipolar mania, or dementia.

Antipsychotic Agents↗

PubMed2003

Extrapyramidal symptom profiles assessed with the Drug-Induced Extrapyramidal Symptom Scale: comparison with Western scales in the clinical double-blind studies of schizophrenic patients treated with either olanzapine or haloperidol.

The superiority of olanzapine to haloperidol with respect to a decreased incidence of treatment-emergent extrapyramidal syndromes (EPS) in patients with schizophrenia was demonstrated in studies conducted in both Japan and Western countries. EPS measurements used in Western countries included the Simpson-Angus, Barnes akathisia and the Abnormal Involuntary Movement Scale, while the Drug-Induced Extrapyramidal Symptom Scale (DIEPSS) was used in Japan. The aim of this study was to clarify how the DIEPSS captures EPS profiles. The baseline prevalence and treatment-emergent incidence of EPS in Japanese schizophrenic patients treated with olanzapine or haloperidol were retrospectively compared as assessed by the DIEPSS to the prevalence and incidence of EPS in primarily Caucasian schizophrenic patients who were treated with olanzapine or haloperidol. Specifically, the prevalence and incidence of dyskinesia, akathisia and parkinsonism were compared between the Japanese trial and an international trial to examine if appropriate definitions using the DIEPSS can be derived assuming that a comparable prevalence and incidence of the syndromes would be observed when any differences in residual antipsychotic exposure at the initiation of study treatment were accounted for. For the incidence of all EPS syndromes, odds ratios were observed to be similar between the two studies, indicating that appropriate criteria for the clinical diagnosis of the EPS syndromes could be established based on the DIEPSS. This preliminary and retrospective work suggests that the DIEPSS can be used to operationally define the presence or absence, and make the clinical diagnosis, of specific EPS syndromes.

Adult↗

PubMed2003

A double-blind, randomized, placebo-controlled trial of olanzapine in the prevention of psychotic relapse.

Sustained response to antipsychotic therapy is an important outcome measure for patients with psychotic disorders. Placebo control in studies of relapse prevention contributes valuable information yet provokes much debate. This study, using placebo as a control, evaluated olanzapine's efficacy in preventing a psychotic relapse. Participants were stable minimally symptomatic outpatients with schizophrenia or schizoaffective disorder. The study included 4 phases: (1) 4-day to 9-day screening/evaluation (N = 583), (2) 6-week conversion to open-label olanzapine (N = 493; 10-20 mg/d), (3) 8-week stabilization on olanzapine (N = 458; 10-20 mg/d), and (4) 52-week randomized (2:1), double-blind maintenance with olanzapine (N = 224; 10-20 mg/d) or placebo (N = 102). Primary relapse criteria were clinically significant changes in the Brief Psychiatric Rating Scale (BPRS) positive item cluster or rehospitalization due to positive symptoms. Statistical methodology allowed sequential real-time estimation of efficacy across blinded treatment groups and multiple interim analyses, which permitted study termination when efficacy was significantly different between treatments. A significant between-treatment difference emerged 210 days after first patient randomization to double-blind treatment. Thus, 151 (46.3%) of the randomized patients were discontinued early and 34 (10.4%) of the planned patient enrollment were not required. The olanzapine group had a significantly longer time to relapse (P < 0.0001) than the placebo group. The 6-month cumulative estimated relapse rate (Kaplan-Meier) was 5.5% for olanzapine-treated patients versus 55.2% for placebo-treated patients. The design of this study enabled appropriate statistical testing of the primary hypothesis while minimizing exposure of patients to a less effective treatment than olanzapine. In remitted stabilized patients with schizophrenia or schizoaffective disorder, olanzapine demonstrated a positive benefit-to-risk profile in relapse prevention.

Adolescent↗

PubMed2003

Tadalafil has no detrimental effect on human spermatogenesis or reproductive hormones.

PURPOSE: We assessed the effects on spermatogenesis of placebo vs 10 or 20 mg tadalafil administered daily for 6 months to healthy men and men with mild erectile dysfunction. MATERIALS AND METHODS: In 2 studies 421 healthy men or men with mild erectile dysfunction who were 45 years or older and met semen criteria derived from WHO reference values were randomized to 6 months of treatment with placebo (101) or 10 mg tadalafil (103), or to placebo (106) or 20 mg tadalafil (111). Semen samples and serum for reproductive hormones (testosterone, luteinizing hormone and follicle-stimulating hormone) were collected at baseline, after 3 months and at the end of treatment. RESULTS: Tadalafil had no adverse effects on spermatogenesis, as assessed by sperm concentration, sperm count per ejaculate, percent sperm motility, normal morphology or serum reproductive hormones. Tadalafil was well tolerated. Common adverse events were headache, dyspepsia and back pain. CONCLUSIONS: Chronic daily administration of tadalafil at doses of 10 and 20 mg for 6 months had no adverse effects on spermatogenesis or on reproductive hormones in men older than 45 years.

3',5'-Cyclic-GMP Phosphodiesterases↗

PubMed2003

An integrated analysis of acute treatment-emergent extrapyramidal syndrome in patients with schizophrenia during olanzapine clinical trials: comparisons with placebo, haloperidol, risperidone, or clozapine.

BACKGROUND: The frequency and severity of extrapyramidal syndrome (EPS) were evaluated in patients with DSM-III or DSM-IV schizophrenia in the acute phase (- 8 weeks) of randomized, double-blind, controlled trials from the integrated olanzapine clinical trial database. METHOD: This retrospective analysis included 23 clinical trials and 4611 patients from November 11, 1991, through July 31, 2001. Incidences of dystonic, parkinsonian, and akathisia events were compared using treatment-emergent adverse-event data. Categorical analyses of Simpson-Angus Scale and Barnes Akathisia Scale (BAS) scores, use of anticholinergic medications, and baseline-to-endpoint changes in Simpson-Angus Scale and BAS scores were compared. RESULTS: A significantly smaller percentage of olanzapine-treated patients experienced dystonic events than did haloperidol- (p <.001) or risperidone-treated patients (p =.047). A significantly greater percentage of haloperidol-treated patients experienced parkinsonian (p <.001) and akathisia (p <.001) events than did olanzapine-treated patients. Categorical analysis of Simpson-Angus Scale scores showed significantly more haloperidol- (p <.001) or risperidone-treated patients (p =.004) developed parkinsonism than did olanzapine-treated patients. Olanzapine-treated patients experienced significantly greater reductions in Simpson-Angus Scale scores than did haloperidol- (p <.001), risperidone- (p <.001), or clozapine-treated (p =.032) patients. Categorical analysis of BAS scores showed significantly more haloperidol-treated patients experienced treatment-emergent akathisia versus olanzapine-treated patients (p <.001). Significantly greater reductions in BAS scores were experienced during olanzapine treatment versus placebo (p =.007), haloperidol (p <.001), and risperidone (p =.004) treatments. A significantly smaller percentage of olanzapine-treated patients received anticholinergic medications compared with that of haloperidol- (p <.001) or risperidone-treated patients (p =.018). Compared with that in olanzapine-treated patients, the duration of anticholinergic cotreatment was significantly longer among haloperidol- (p <.001) or risperidone-treated patients (p =.040) and significantly shorter among clozapine-treated patients (p =.021). CONCLUSION: This analysis of available data from olanzapine clinical trials lends additional support to olanzapine's favorable EPS profile.

Acute Disease↗

PubMed2002

Fluoxetine and norfluoxetine plasma concentrations during relapse-prevention treatment.

BACKGROUND: Virtually no attention has been given to the relationship between antidepressant plasma drug concentrations and relapse-prevention during maintenance therapy. The purpose of this study was to investigate the relationship between steady-state plasma drug concentrations and outcome during relapse-prevention therapy with fluoxetine. METHODS: The patients studied had responded to acute fluoxetine treatment for major depression (defined by DSM-III-R). Patients who met criteria for remission after 10-12 weeks of open-label acute fluoxetine therapy (N=395 of 839 patients), were randomly assigned to one of four treatment arms (50 weeks of fluoxetine, 38 weeks of fluoxetine followed by 12 weeks of placebo, 14 weeks of fluoxetine followed by 36 weeks of placebo and 50 weeks of placebo). Plasma fluoxetine and norfluoxetine concentrations were measured (1) after 4 and 8 weeks of open-label treatment and (2) at the beginning and after 14 weeks of double-blind, relapse-prevention therapy. RESULTS: Mean drug plasma levels were stable throughout the study. There was no significant difference in steady state plasma levels for the patients who relapsed compared to those who completed fluoxetine therapy without relapsing after 14, 38 or 50 weeks of fluoxetine relapse-prevention treatment. In addition, time-to-relapse was not related to steady-state drug plasma levels. Finally, after dividing patients into two groups based on their drug plasma levels, no significant differences were seen in the cumulative proportions of patients staying well during relapse-prevention therapy. DISCUSSION: Plasma concentrations of fluoxetine and/or its metabolite norfluoxetine, are not correlated with relapse in patients treated with a fixed dose of 20 mg/day fluoxetine. Fluoxetine plasma levels cannot be used to guide relapse-prevention treatment.

Adolescent↗

PubMed2002

Comparison of rapidly acting intramuscular olanzapine, lorazepam, and placebo: a double-blind, randomized study in acutely agitated patients with dementia.

This double-blind study investigated the efficacy and safety of rapid-acting intramuscular olanzapine in treating agitation associated with Alzheimer's disease and/or vascular dementia. At 2 h, olanzapine (5.0 mg, 2.5 mg) and lorazepam (1.0 mg) showed significant improvement over placebo on the PANSS Excited Component (PANSS-EC) and Agitation-Calmness Evaluation Scale (ACES), and both 5.0 mg olanzapine and lorazepam showed superiority to placebo on the Cohen-Mansfield Agitation Inventory. At 24 h, both olanzapine groups maintained superiority over placebo on the PANSS-EC; lorazepam did not. Olanzapine (5.0 mg) and lorazepam improved ACES scores more than placebo. Simpson-Angus and Mini-Mental State Examination scores did not change significantly from baseline. Sedation (ACES > or =8), adverse events, and laboratory analytes were not significantly different from placebo for any treatment. No significant differences among treatment groups were seen in extrapyramidal symptoms or in corrected QT interval at either 2 h or 24 h, and no significant differences among treatment groups were seen in vital signs, including orthostasis. Intramuscular injection of olanzapine may therefore provide substantial benefit in rapidly treating inpatients with acute dementia-related agitation.

Acute Disease↗

PubMed2002

Hyperglycemic clamp assessment of insulin secretory responses in normal subjects treated with olanzapine, risperidone, or placebo.

The goal of this study was to evaluate the effect of olanzapine or risperidone treatment on beta-cell function in healthy volunteers. Subjects were randomly assigned to single-blind therapy with olanzapine (10 mg/d; n = 17), risperidone (4 mg/d; n = 13), or placebo (n = 18) for 15-17 d. Insulin secretion was quantitatively assessed at baseline and the end of the study period using the hyperglycemic clamp. Weight increased significantly (P < 0.01) in the olanzapine (2.8 +/- 1.7 kg) and risperidone (3.1 +/- 2.1 kg) treatment groups. An increase ( approximately 25%) in the insulin response to hyperglycemia and a decrease ( approximately 18%) in the insulin sensitivity index were observed after treatment with olanzapine and risperidone. The change in insulin response was correlated (r = 0.5576; P = 0.019) with a change in body mass index. When the impact of weight change was accounted for by multivariate regression analyses, no significant change in insulin response or insulin sensitivity was detected after treatment with olanzapine or risperidone. We found no evidence that treatment of healthy volunteers with olanzapine or risperidone decreased the insulin secretory response to a prolonged hyperglycemic challenge. The results of this study do not support the hypothesis that olanzapine or risperidone directly impair pancreatic beta-cell function.

Adult↗

PubMedDate not supplied

Tadalafil improved erectile function at twenty-four and thirty-six hours after dosing in men with erectile dysfunction: US trial.

In a previous study assessing tadalafil for the treatment of erectile dysfunction (ED), tadalafil 20 mg was shown to improve erectile function for up to 36 hours vs placebo. This study sought to demonstrate the effectiveness of both 10- and 20-mg tadalafil vs placebo at 2 prespecified assigned times of 24 and 36 hours postdosing. This double-blind, placebo-controlled, parallel-group study randomized 483 men with ED into 6 groups according to a combination of treatment (placebo, tadalafil 10 or 20 mg) and assigned time (24 or 36 hours) for intercourse attempts. Patients were stratified by baseline ED severity based on Erectile Function Domain scores. The study had 4 phases: a 4-week run-in (no ED medication taken); a 2- to 4-week equilibration (dosing as needed); a 4- to 6-week assessment; and a 6-month open-label extension. During the assessment phase, men took a total of 4 doses of study medication, each dose separated by more than or equal to 7 days. Efficacy was measured as the mean per-patient percentage of successful intercourse attempts (Sexual Encounter Profile Diary Question 3: SEP3) during the assessment phase. Men taking either 10- or 20-mg tadalafil had a significant increase in SEP3 from baseline scores vs placebo at both 24 hours (P = .038 and <.001 for 10 and 20 mg, respectively) and 36 hours (P < .001 for both doses) postdose. The mean per-patient percentages of successful intercourse attempts for the 24-hour time point were 41.8%, 55.8%, and 67.3% for placebo and tadalafil 10 and 20 mg, respectively; for the 36-hour time point, the mean per-patient percentages were 32.8%, 56.2%, and 61.9% for placebo and tadalafil 10 and 20 mg, respectively. The most common treatment-emergent adverse events were headache, back pain, dyspepsia, and nasopharyngitis. Both 10- and 20-mg tadalafil improved erectile function for up to 36 hours postdosing in men with ED of varied severity.

3',5'-Cyclic-GMP Phosphodiesterases↗