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Dive into the research topics where Karen R. Reeves is active.

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Featured researches published by Karen R. Reeves.


Neuropsychopharmacology | 1999

Ziprasidone 80 mg/day and 160 mg/day in the Acute Exacerbation of Schizophrenia and Schizoaffective Disorder: A 6-Week Placebo-Controlled Trial

David G. Daniel; Dan L. Zimbroff; Steven G. Potkin; Karen R. Reeves; Edmund Patrick Harrigan; Mani Lakshminarayanan

In this double-blind study, patients with an acute exacerbation of schizophrenia or schizoaffective disorder were randomized to receive either ziprasidone 80 mg/day (n = 106) or 160 mg/day (n = 104) or placebo (n = 92), for 6 weeks. Both doses of ziprasidone were statistically significantly more effective than placebo in improving the PANSS total, BPRS total, BPRS core items, CGI-S, and PANSS negative subscale scores (p < .05). Ziprasidone 160 mg/day significantly improved depressive symptoms in patients with clinically significant depression at baseline (MADRS ≥ 14, over-all mean 23.5) (p < .05) as compared with placebo. The percentage of patients experiencing adverse events was similar in each treatment group, and resultant discontinuation was rare. The most frequent adverse events associated with ziprasidone were generally mild dyspepsia, nausea, dizziness, and transient somnolence. Ziprasidone was shown to have a very low liability for inducing movement disorders and weight gain. The results indicate that ziprasidone is effective and well tolerated in the treatment of the positive, negative, and depressive symptoms of an acute exacerbation of schizophrenia or schizoaffective disorder.


Thorax | 2008

Varenicline versus transdermal nicotine patch for smoking cessation: Results from a randomised, open-label trial

Henri-Jean Aubin; Alex Bobak; John Britton; Cheryl Oncken; Clare B. Billing; Jason Gong; Kathryn E. Williams; Karen R. Reeves

Background: Varenicline, a new treatment for smoking cessation, has demonstrated significantly greater efficacy over placebo and sustained release bupropion (bupropion SR). A study was undertaken to compare a 12-week standard regimen of varenicline with a 10-week standard regimen of transdermal nicotine replacement therapy (NRT) for smoking cessation. Methods: In this 52-week, open-label, randomised, multicentre, phase 3 trial conducted in Belgium, France, the Netherlands, UK and USA, participants were randomly assigned (1:1) to receive varenicline uptitrated to 1 mg twice daily for 12 weeks or transdermal NRT (21 mg/day reducing to 7 mg/day) for 10 weeks. Non-treatment follow-up continued to week 52. The primary outcome was the biochemically confirmed (exhaled carbon monoxide ⩽10 ppm) self-reported continuous abstinence rate (CAR) for the last 4 weeks of the treatment period in participants who had taken at least one dose of treatment. Secondary outcomes included CAR from the last 4 weeks of treatment through weeks 24 and 52, and measures of craving, withdrawal and smoking satisfaction. Results: A total of 376 and 370 participants assigned to varenicline and NRT, respectively, were eligible for analysis. The CAR for the last 4 weeks of treatment was significantly greater for varenicline (55.9%) than NRT (43.2%; OR 1.70, 95% CI 1.26 to 2.28, p<0.001). The week 52 CAR (NRT, weeks 8–52; varenicline, weeks 9–52) was 26.1% for varenicline and 20.3% for NRT (OR 1.40, 95% CI 0.99 to 1.99, p = 0.056). Varenicline significantly reduced craving (p<0.001), withdrawal symptoms (p<0.001) and smoking satisfaction (p<0.001) compared with NRT. The most frequent adverse event was nausea (varenicline, 37.2%; NRT, 9.7%). Conclusions: The outcomes of this trial established that abstinence from smoking was greater and craving, withdrawal symptoms and smoking satisfaction were less at the end of treatment with varenicline than with transdermal NRT. Trial registration number: NCT00143325.


Journal of Clinical Psychopharmacology | 2004

A Randomized Evaluation of the Effects of Six Antipsychotic Agents on Qtc, In the Absence and Presence of Metabolic Inhibition

Edmund Patrick Harrigan; Jeffrey J. Miceli; Richard J. Anziano; Eric Jacob Watsky; Karen R. Reeves; Neal R. Cutler; T. John Sramek; Thomas Shiovitz; Michelle Middle

Many drugs have been associated with QTc prolongation and, in some cases, this is augmented by concomitant administration with metabolic inhibitors. The effects of 6 antipsychotics on the QTc interval at and around the time of estimated peak plasma/serum concentrations in the absence and presence of metabolic inhibition were characterized in a prospective, randomized study in which patients with psychotic disorders reached steady-state on either haloperidol 15 mg/d (n = 27), thioridazine 300 mg/d (n = 30), ziprasidone 160 mg/d (n = 31), quetiapine 750 mg/d (n = 27), olanzapine 20 mg/d (n = 24), or risperidone 6-8 mg/d increased to 16 mg/d (n = 25/20). Electrocardiograms (ECGs) were done at estimated Cmax at steady-state on both antipsychotic monotherapy and after concomitant administration of appropriate cytochrome P-450 (CYP450) inhibitor(s). Mean QTc intervals did not exceed 500 milliseconds in any patient taking any of the antipsychotics studied, in the absence or presence of metabolic inhibition. The mean QTc interval change was greatest in the thioridazine group, both in the presence and absence of metabolic inhibition. The presence of metabolic inhibition did not significantly augment QTc prolongation associated with any agent. Each of the antipsychotics studied was associated with measurable QTc prolongation at steady-state peak plasma concentrations, which was not augmented by metabolic inhibition. The theoretical risk of cardiotoxicity associated with QTc prolongation should be balanced against the substantial clinical benefits associated with atypical antipsychotics and the likelihood of other toxicities.


Current Medical Research and Opinion | 2007

A double-blind study evaluating the long-term safety of varenicline for smoking cessation

Kathryn E. Williams; Karen R. Reeves; Clare B. Billing; Ann M. Pennington; Jason Gong

ABSTRACT Objective: We assessed the safety of long-term varenicline administration for smoking cessation. Methods: In this randomized, double-blind, multicenter trial, eligible adult smokers (18–75 years) who smoked an average of ≥10 cigarettes/day were randomized to either varenicline 1 mg twice daily (BID) or placebo for 52 weeks. Subjects made weekly clinic visits until week 8, and then every 4 weeks until week 52, with a follow-up visit at week 53. The target quit date was the morning of the week 1 clinic visit. Brief counseling was provided at each visit, and vital signs, adverse events (AEs), and smoking status were documented. Other laboratory measures were collected at specified visits. Results: A total of 251 subjects were randomized to varenicline and 126 to placebo. Approximately half of the subjects in each arm completed the study (53.8% varenicline; 46.8% placebo). Treatment-emergent AEs were observed in 96.4% of varenicline- and 82.5% of placebo-treated subjects during the study. Common varenicline-associated AEs were nausea (40.2%), abnormal dreams (22.7%), and insomnia (19.1%). Most AEs were considered mild or moderate in intensity. AEs leading to discontinuation of varenicline treatment included nausea (7.6%), insomnia (3.2%), and abnormal dreams (2.4%). A single varenicline-related serious AE, bilateral subcapsular cataracts, was observed. At week 52, 7-day point prevalence abstinence rates were 36.7% (varenicline) and 7.9% (placebo). Conclusions: Varenicline 1 mg BID can be safely administered for up to 1 year. Varenicline was also a more effective smoking cessation aid than placebo throughout the study, supporting both its short- (12-week) and long-term (52-week) efficacy. Trial registration: ClinicalTrials.gov identifier: NCT00143299.


Current Medical Research and Opinion | 2008

The efficacy and safety of varenicline for smoking cessation using a flexible dosing strategy in adult smokers: a randomized controlled trial.

Raymond Niaura; J. Taylor Hays; Douglas E. Jorenby; Frank T. Leone; John E. Pappas; Karen R. Reeves; Kathryn E. Williams; Clare B. Billing

ABSTRACT Objective: To determine whether self-regulated flexible dosing with varenicline tartrate is safe and effective for smoking cessation. Research design and methods: 320 healthy, motivated-to-quit smokers (≥10 cigarettes/day) aged 18–65 years, entered a multicenter, randomized, double-blind, placebo-controlled study – conducted between December 26, 2001 and June 24, 2003 – with a 12-week treatment phase and 40-week, double-blind, non-treatment follow-up. Treatment consisted of varenicline or placebo in fixed doses (Week 1: titrated from 0.5 to 1.0 mg/day) followed by a self-regulated flexible schedule (Weeks 2–12: 0.5–2.0 mg/day). Main outcome measures: Primary outcomes included carbon monoxide-confirmed continuous abstinence rate (CAR) from smoking for Weeks 4 through 7, 9 through 12, and 9 through 52. Secondary outcomes included CAR from Weeks 9 through 24, 7-day point prevalence of abstinence, safety assessments, and measures of craving, withdrawal, and smoking reward. Results: Superior CARs were observed in varenicline-treated (n = 157) versus placebo participants (n = 155) for Weeks 4 through 7 (38.2 vs. 11.6%), 9 through 12 (40.1 vs. 11.6%), 9 through 24 (28.0 vs. 9.0%), and 9 through 52 (22.3 vs. 7.7%) (all p < 0.001). Seven-day point prevalence was higher in varenicline-treated than placebo participants at Weeks 12 (46.5 vs. 14.2%; p < 0.001), 24 (32.5 vs. 13.5%; p < 0.001), and 52 (28.0 vs. 13.5%; p = 0.001). Overall, medication compliance was high, although varenicline-treated, but not placebo, participants tended to taper down their dosage over time. Total treatment-emergent AEs were 77.1% (varenicline: 121/157) and 65.8% (placebo: 102/155). Few AEs led to treatment discontinuation (varenicline: 11/157, 7.0% and placebo: 7/155, 4.5%). Participants were primarily healthy Caucasians, so more research is necessary to determine how applicable these findings are to other populations. Conclusions: A self-regulated, flexible dosing regimen of varenicline is well tolerated, with superior effectiveness versus placebo for smoking cessation. Trial registration: ClinicalTrials.gov identifier: NCT00150228.


Journal of Clinical Psychopharmacology | 2001

Ziprasidone in the short-term treatment of patients with schizoaffective disorder: results from two double- blind, placebo-controlled, multicenter studies.

Paul E. Keck; Karen R. Reeves; Edmund Patrick Harrigan

This study assessed the efficacy of ziprasidone for the treatment of schizoaffective disorder. Data were taken from subsets of patients with schizoaffective disorder, derived from two separate double-blind, placebo-controlled, parallel-group, multicenter studies. A total of 115 hospitalized patients with an acute episode of schizoaffective disorder were randomly assigned to receive either fixed oral doses of ziprasidone 40 mg/day (N = 16), 80 mg/day (N = 18), 120 mg/day (N = 22), 160 mg/day (N = 25), or placebo (N = 34) for 4 to 6 weeks. Mean baseline-to-endpoint changes in Brief Psychiatric Rating Scale (BPRS) total, BPRS Core, Clinical Global Impressions Severity scale (CGI-S), BPRS Depressive, BPRS Manic, and Montgomery-Åsberg Depression Rating Scale total scores were compared between the placebo and ziprasidone groups. Neurological (Simpson-Angus, Barnes Akathisia, Abnormal Involuntary Movement Scale [AIMS]) and other side effects were also assessed. Significant dose-related improvements on all primary efficacy variables (BPRS total, BPRS Core, CGI-S) and for BPRS Manic items were observed with ziprasidone treatment in a combined analysis of data from both studies (p ≤ 0.01). Ziprasidone 160 mg/day was significantly more effective than placebo in improving mean BPRS total, BPRS Core, BPRS Manic, and CGI-S scores (p < 0.05). At 120 mg/day, ziprasidone was significantly more effective than placebo in improving mean CGI-S scores (p < 0.05). The incidence of individual adverse events was generally low in all treatment groups and was not dose-related. In addition, no significant differences were observed between baseline-to-endpoint mean changes in Simpson-Angus and AIMS scores with placebo or ziprasidone 40 to 160 mg/day. These results suggest that ziprasidone may have efficacy in the treatment of affective as well as psychotic symptoms of schizoaffective disorder, with a low side-effect burden.


Current Medical Research and Opinion | 2008

Comment and Reply: A double-blind study evaluating the long-term safety of varenicline for smoking cessation

John G. Spangler; K. E. Williamsa; Karen R. Reeves; Clare B. Billing; A. M. Pennington; Jason Gong

OBJECTIVE We assessed the safety of long-term varenicline administration for smoking cessation. METHODS In this randomized, double-blind, multicenter trial, eligible adult smokers (18-75 years) who smoked an average of > or =10 cigarettes/day were randomized to either varenicline 1 mg twice daily (BID) or placebo for 52 weeks. Subjects made weekly clinic visits until week 8, and then every 4 weeks until week 52, with a follow-up visit at week 53. The target quit date was the morning of the week 1 clinic visit. Brief counseling was provided at each visit, and vital signs, adverse events (AEs), and smoking status were documented. Other laboratory measures were collected at specified visits. RESULTS A total of 251 subjects were randomized to varenicline and 126 to placebo. Approximately half of the subjects in each arm completed the study (53.8% varenicline; 46.8% placebo). Treatment-emergent AEs were observed in 96.4% of varenicline- and 82.5% of placebo-treated subjects during the study. Common varenicline-associated AEs were nausea (40.2%), abnormal dreams (22.7%), and insomnia (19.1%). Most AEs were considered mild or moderate in intensity. AEs leading to discontinuation of varenicline treatment included nausea (7.6%), insomnia (3.2%), and abnormal dreams (2.4%). A single varenicline-related serious AE, bilateral subcapsular cataracts, was observed. At week 52, 7-day point prevalence abstinence rates were 36.7% (varenicline) and 7.9% (placebo). CONCLUSIONS Varenicline 1 mg BID can be safely administered for up to 1 year. Varenicline was also a more effective smoking cessation aid than placebo throughout the study, supporting both its short- (12-week) and long-term (52-week) efficacy.


Schizophrenia Research | 1997

576 – The efficacy and safety of ziprasidone 80 mg/day and 160mg/day in schizophrenia and schizoaffecfive disorder

David G. Daniel; Karen R. Reeves; Edmund Patrick Harrigan

Ziprasidones high affinity for SHT1A and moderate affinity for D1 receptors suggest significant antipsychotic efficacy with low extrapyramidal side-effect (EPS) liability. This 6-week, double-blind, placebo-controlled study compared the efficacy and safety ofziprasidone in patients with an acute exacerbation of schizophrenia or schizoaffective disorder. After a 3-7 day washout, patients received either ziprasidone 40 mg bid (n= 106); ziprasidone 40 mg bid on days 1-2 then 80 mg bid (n= 104); or placebo (n=92). Both 80 mg and 160 mg/day ziprasidone significantly improved Brief Psychiatric Rating Scale (BPRSd) derived from the Positive and Negative Syndrome Scale (PANSS), BPRSd Core Items, Clinical Global Impression (CGI) Severity, and PANSS Total scores compared with placebo. Improvements in negative symptoms (PANSS Negative Subscale) were significantly greater and improvements in MADRS also greater with both ziprasidone doses compared with placebo. Notable was the low incidence of EPS, akathisia and sexual dysfunction associated with ziprasidone. Discontinuations due to adverse events were infrequent and similar among groups (4.7-9.6%). The results of this study indicate that ziprasidone is an effective and well tolerated antipsychotic, improving positive, negative and affective symptoms without an undue side-effect burden. • The authors thank the Ziprasidone Study Group for participation in this study.


JAMA | 2006

Efficacy of Varenicline, an 42 Nicotinic Acetylcholine Receptor Partial Agonist, vs Placebo or Sustained-Release Bupropion for Smoking Cessation A Randomized Controlled Trial

Douglas E. Jorenby; J. Taylor Hays; Nancy A. Rigotti; Salomon Azoulay; Eric Jacob Watsky; Kathryn E. Williams; Clare B. Billing; Jason Gong; Karen R. Reeves


JAMA | 2006

Varenicline, an 42 Nicotinic Acetylcholine Receptor Partial Agonist, vs Sustained-Release Bupropion and Placebo for Smoking Cessation A Randomized Controlled Trial

David Gonzales; Stephen I. Rennard; Mitchell A. Nides; Cheryl Oncken; Salomon Azoulay; Clare B. Billing; Eric Jacob Watsky; Jason Gong; Kathryn E. Williams; Karen R. Reeves

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Cheryl Oncken

University of Connecticut

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Stephen I. Rennard

University of Nebraska Medical Center

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David G. Daniel

National Institutes of Health

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