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Dive into the research topics where Sara Kollack-Walker is active.

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Featured researches published by Sara Kollack-Walker.


Journal of Clinical Psychopharmacology | 2011

A multicenter, inpatient, phase 2, double-blind, placebo-controlled dose-ranging study of LY2140023 monohydrate in patients with DSM-IV schizophrenia

Bruce J. Kinon; L. Zhang; Brian A. Millen; Olawale Osuntokun; Judy E. Williams; Sara Kollack-Walker; Kimberley Jackson; Ludmila Kryzhanovskaya; Natalia Jarkova

The primary objective of this study was to test the hypothesis that 1 or more dose levels of LY2140023 monohydrate, an oral prodrug of the potent metabotropic glutamate (mGlu) 2/3 receptor agonist LY404039, given to patients with schizophrenia for 4 weeks would demonstrate significantly greater efficacy than placebo. The HBBI study was a multicenter, randomized, double-blind, parallel, placebo- and active-controlled trial. Male and female patients aged 18 to 65 years who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for schizophrenia were randomized in a 2:2:2:2:2:1 ratio to receive 5-, 20-, 40-, or 80-mg LY2140023 monohydrate twice daily, placebo twice daily, or placebo (am) and 15 mg of olanzapine (pm) daily. Efficacy was defined as the change from baseline on the Positive and Negative Syndrome Scale (PANSS) total score assessed at 4 weeks. The primary analysis did not show that any of the 4 LY2140023 monohydrate doses were more efficacious than placebo as measured by the PANSS total score. Similarly, olanzapine did not significantly separate from placebo. A higher-than-anticipated treatment effect (14.6-point improvement) in the placebo group was observed on PANSS total score. LY2140023 monohydrate was generally well tolerated, although 4 patients reported the serious adverse event of convulsion. LY2140023 monohydrate-treated patients showed little change in dopamine-related adverse events and weight. The results of the HBBI study are considered to be inconclusive because LY2140023 monohydrate and the active control olanzapine did not separate from placebo in the treatment of patients with acutely exacerbated schizophrenia. Additional efficacy, safety, and tolerability testing are needed.


Journal of Clinical Psychopharmacology | 2005

Association between early and rapid weight gain and change in weight over one year of olanzapine therapy in patients with schizophrenia and related disorders.

Bruce J. Kinon; Christopher Kaiser; Saeed Ahmed; Matthew Rotelli; Sara Kollack-Walker

Abstract: Weight gain is an important issue in the use of atypical antipsychotics, including olanzapine. A retrospective analysis of patterns of weight gain and possible covariates was performed for 1191 patients diagnosed with schizophrenia or schizoaffective disorder who were treated with olanzapine for up to 52 weeks. Patients were dichotomized into 2 main groups according to the percentage of body weight gained during the first 6 weeks of treatment with olanzapine: (1) patients who gained ≥7% of their body weight (Rapid Weight Gain Group [RWG]), and (2) patients who lost weight, gained no weight, or gained <7% of their body weight (Nonrapid Weight Gain Group [NRWG]). Results demonstrated that approximately 15% of the patient population showed rapid increases in weight (RWG group), whereas 85% of patients gained weight more slowly or not at all (NRWG group). Patients in the RWG group gained an average of 4% of their body weight (approximately 4-7 lb) within the first 2 weeks of treatment with olanzapine. Furthermore, patients in the RWG group were younger, had a lower baseline body mass index, were more likely to report an increase in appetite, and showed a more robust clinical response compared with patients in the NRWG group. Over the course of 52 weeks, patients in the RWG group gained significantly more weight and reached a higher plateau for mean weight increase at 38 weeks compared with the mean increase observed for patients in the NRWG group. By measuring the weight of patients during the first few weeks of olanzapine treatment and by assessing changes in appetite, clinicians may be able to identify those patients at risk for substantial weight gain.


Neuropsychopharmacology | 2010

Early Response to Antipsychotic Drug Therapy as a Clinical Marker of Subsequent Response in the Treatment of Schizophrenia

Bruce J. Kinon; Lei Chen; Haya Ascher-Svanum; Virginia L. Stauffer; Sara Kollack-Walker; Wei Zhou; Shitij Kapur; John M. Kane

Our objective was to prospectively assess whether early (ie, 2 weeks) response to an antipsychotic predicts later (12-week) response and whether ‘switching’ early non-responders to another antipsychotic is a better strategy than ‘staying’. This randomized, double-blind, flexible-dosed, 12-week study enrolled 628 patients diagnosed with schizophrenia or schizoaffective disorder. All initiated treatment with risperidone. Early response was defined as ⩾20% improvement on the Positive and Negative Syndrome Scale (PANSS) total score following 2 weeks of treatment. Early responders (ERs) continued on risperidone, whereas early non-responders (ENRs) were randomized (1 : 1) to continue on risperidone 2–6 mg/day or switch to olanzapine 10–20 mg/day for 10 additional weeks. Compared with ENRs, risperidone ERs showed significantly greater reduction in PANSS total score (end point; p<001). Early response/non-response was highly predictive of subsequent clinical outcomes. Switching risperidone ENRs to olanzapine at week 2 resulted in a small but significantly greater reduction in PANSS total score (end point; p=0.020) and in depressive symptoms (end point; p=0.004); the reduction in PANSS was greater among those who were still moderately ill at 2 weeks. Switching risperidone ENRs to olanzapine also resulted in significantly greater increases in triglycerides, a significantly greater decrease in prolactin, and significantly less treatment-emergent dyskinesia. This is the first study to prospectively show that early response/non-response to an antipsychotic (risperidone) is a reliable clinical marker of subsequent clinical outcomes and that a ‘switching’ strategy based on this information may lead to greater clinical improvement than staying on a drug for a longer period in some patients.


Journal of Clinical Psychopharmacology | 2006

Randomized, double-blind 6-month comparison of olanzapine and quetiapine in patients with schizophrenia or schizoaffective disorder with prominent negative symptoms and poor functioning.

Bruce J. Kinon; Douglas L. Noordsy; Hong Liu-Seifert; Angela H. Gulliver; Haya Ascher-Svanum; Sara Kollack-Walker

Abstract: This study compared the effects of olanzapine (OLZ) with those of quetiapine (QUE) for improving negative symptoms in patients diagnosed with schizophrenia or schizoaffective disorder who had prominent negative symptoms and marked deficits in social or occupational functioning. In this 6-month, multicenter, double-blind clinical trial, patients were randomized to treatment with OLZ (n = 171, 10-20 mg/d) or QUE (n = 175, 300-700 mg/d). Patients were treated at community mental health centers and assigned case managers who developed individualized psychosocial treatment plans. The primary efficacy measure was the reduction in negative symptoms using the Scale for the Assessment of Negative Symptoms. Secondary measures assessed changes in functioning, psychopathology, and treatment tolerability. Treatment with OLZ or QUE led to a significant reduction in negative symptoms, with no between-group difference (P = 0.09). Both treatment groups also showed significant improvement on most efficacy measures. Olanzapine-treated patients showed significantly greater improvement on positive symptoms and on several measures of functioning including Global Assessment of Functioning Scale, Quality of Life Instrumental Role domain, and level of effort in psychosocial or occupational rehabilitation programs. Significantly more OLZ-treated patients completed the study (52.6% OLZ, 37.7% QUE, P = 0.007). Treatment differences in safety were relatively small and not thought to be clinically relevant. Patients with schizophrenia who manifest prominent negative symptoms and marked functional deficits demonstrated significant improvement in negative symptoms after treatment with OLZ or QUE. Greater improvement in positive symptoms and a greater study completion rate may hold relevance to enhanced functional outcomes observed after OLZ therapy.


The International Journal of Neuropsychopharmacology | 2003

Olanzapine orally disintegrating tablets in the treatment of acutely ill non-compliant patients with schizophrenia.

Bruce J. Kinon; Angela L. Hill; Hong Liu; Sara Kollack-Walker

The objective of this study was to determine if the orally disintegrating tablet formulation of olanzapine, Zyprexa Zydis, would facilitate antipsychotic medication compliance in acutely ill, non-compliant patients. Eighty-five acutely ill patients with schizophrenia or schizoaffective disorder who met medication non-compliance criteria received open-label olanzapine orally disintegrating tablets (1020 mgd) for up to 6 wk. Improvement in medication compliance was assessed using various rating scales to measure changes in psychopathology, medication-taking and compliance attitudes, and nursing care burden. Safety variables were also measured. Significant improvement from baseline was demonstrated in the Positive and Negative Syndrome Scale total score at Week 1 and subsequently (p0.001). Significant improvement from baseline was also seen in various scales measuring medication compliance, attitude, and nursing care burden (p0.05). Olanzapine orally disintegrating tablets were well-tolerated. Olanzapine orally disintegrating tablets may benefit acutely ill, non-compliant schizophrenic patients by facilitating acceptance of active antipsychotic drug therapy.


BMC Psychiatry | 2009

Relationships among neurocognition, symptoms and functioning in patients with schizophrenia: a path-analytic approach for associations at baseline and following 24 weeks of antipsychotic drug therapy

Ilya Lipkovich; Walter Deberdt; John G. Csernansky; Bernard Sabbe; Richard S.E. Keefe; Sara Kollack-Walker

BackgroundNeurocognitive impairment and psychiatric symptoms have been associated with deficits in psychosocial and occupational functioning in patients with schizophrenia. This post-hoc analysis evaluates the relationships among cognition, psychopathology, and psychosocial functioning in patients with schizophrenia at baseline and following sustained treatment with antipsychotic drugs.MethodsData were obtained from a clinical trial assessing the cognitive effects of selected antipsychotic drugs in patients with schizophrenia. Patients were randomly assigned to 24 weeks of treatment with olanzapine (n = 159), risperidone (n = 158), or haloperidol (n = 97). Psychosocial functioning was assessed with the Heinrichs-Carpenter Quality of Life Scale [QLS], cognition with a standard battery of neurocognitive tests; and psychiatric symptoms with the Positive and Negative Syndrome Scale [PANSS]. A path-analytic approach was used to evaluate the effects of changes in cognitive functioning on subdomains of quality of life, and to determine whether such effects were direct or mediated via changes in psychiatric symptoms.ResultsAt baseline, processing speed affected functioning mainly indirectly via negative symptoms. Positive symptoms also affected functioning at baseline although independent of cognition. At 24 weeks, changes in processing speed affected changes in functioning both directly and indirectly via PANSS negative subscale scores. Positive symptoms no longer contributed to the path-analytic models. Although a consistent relationship was observed between processing speed and the 3 functional domains, variation existed as to whether the paths were direct and/or indirect. Working memory and verbal memory did not significantly contribute to any of the path-analytic models studied.ConclusionProcessing speed demonstrated direct and indirect effects via negative symptoms on three domains of functioning as measured by the QLS at baseline and following 24 weeks of antipsychotic treatment.


Psychological Medicine | 2011

The heterogeneity of antipsychotic response in the treatment of schizophrenia

Mike Case; Virginia L. Stauffer; Haya Ascher-Svanum; Robert R. Conley; Shitij Kapur; John M. Kane; Sara Kollack-Walker; Jayanthi Jacob; Bruce J. Kinon

Background Schizophrenia is a heterogeneous disorder in terms of patient response to antipsychotic treatment. Understanding the heterogeneity of treatment response may help to guide treatment decisions. This study was undertaken to capture inherent patterns of response to antipsychotic treatment in patients with schizophrenia, characterize the subgroups of patients with similar courses of response, and examine illness characteristics at baseline as possible predictors of response. Method Growth mixture modeling (GMM) was applied to data from a randomized, double-blind, 12-week study of 628 patients with schizophrenia or schizo-affective disorder treated with risperidone or olanzapine. Results Four distinct response trajectories based on Positive and Negative Syndrome Scale (PANSS) total score over 12 weeks were identified: Class 1 (420 patients, 80.6%) with moderate average baseline PANSS total score showing gradual symptom improvement; Class 2 (65 patients, 12.5%) showing rapid symptom improvement; Class 3 (24 patients, 4.6%) with high average baseline PANSS total score showing gradual symptom improvement; and Class 4 (12 patients, 2.3%) showing unsustained symptom improvement. Latent class membership of early responders (ER) and early non-responders (ENR) was determined based on 20% symptom improvement criteria at 2 weeks and ultimate responders (UR) and ultimate non-responders (UNR) based on 40% symptom improvement criteria at 12 weeks. Baseline factors with potential influence on latent class membership were identified. Conclusions This study identified four distinct treatment response patterns with predominant representation of responders or non-responders to treatment in these classes. This heterogeneity may represent discrete endophenotypes of response to treatment with different etiologic underpinnings.


Journal of Clinical Psychopharmacology | 2008

Olanzapine versus aripiprazole for the treatment of agitation in acutely ill patients with schizophrenia.

Bruce J. Kinon; Virginia L. Stauffer; Sara Kollack-Walker; Lei Chen; Jennifer Sniadecki

Rapid control of agitation is of critical importance in the treatment of acutely ill patients with schizophrenia. Both olanzapine and aripiprazole have been shown to be safe and effective in this setting, with each having somewhat different receptor binding affinity profiles. This 5-day, randomized, double-blind trial evaluated relative improvements in agitation in hospitalized patients who received orally dosed olanzapine (n = 306, 20 mg/d) or aripiprazole (n = 298, 15 mg/d, increasing to 30 mg/d as needed). Lorazepam was also given as needed (total dose, ≤4 mg/d) but not in place of a study drug dose increase. The primary efficacy measure was daily mean change from baseline in Positive and Negative Syndrome Scale-Excited Component (PANSS-EC) score. Secondary measures of positive symptoms and safety were also assessed. Significant improvements from baseline in PANSS-EC and secondary efficacy measures were seen for both olanzapine and aripiprazole (P < 0.001),with no between-group differences. A greater proportion of aripiprazole-treated patients received lorazepam at each visit compared with olanzapine-treated patients, but this difference was significant only at visit 5 (41.2% vs 31.0%, P = 0.033). Fasting glucose and triglycerides increased more significantly in olanzapine-treated patients (P = 0.030 and P < 0.001, respectively). Prolactin increased in the olanzapine group and decreased in the aripiprazole group with a significant between-group difference (P < 0.001). During the first 5 days of randomized treatment, olanzapine and aripiprazole displayed similar efficacy profiles for treating agitation associated with schizophrenia. Aripiprazole-treated patients had smaller increases in glucose and lipids, but no difference was observed between treatments in the proportion of patients experiencing categorical shifts in these measures.


Psychiatry Research-neuroimaging | 2011

Early response to antipsychotic therapy as a clinical marker of subsequent response in the treatment of patients with first-episode psychosis.

Virginia L. Stauffer; Michael Case; Bruce J. Kinon; Robert R. Conley; Haya Ascher-Svanum; Sara Kollack-Walker; John M. Kane; Joseph P. McEvoy; Jeffrey A. Lieberman

Early response to antipsychotic medication has been shown to accurately predict later response to continued use of the same treatment in patients with chronic schizophrenia. This study examines whether this predictive pattern exists for patients with first-episode psychosis. We used a data-driven threshold for early response of ≥ 26.2% improvement from baseline on the Positive and Negative Syndrome Scale (PANSS(0-6)) Total score to determine whether response at Week 2 of treatment may predict response at Week 12 in a randomized, double-blind trial of olanzapine versus haloperidol for treatment of patients with first-episode psychosis (N=225). Later response was defined as a ≥ 40% and ≥ 50% improvement in PANSS Total(0-6) score and as remission. At Week 2, 43% (97/225) of patients were identified as early responders. At a threshold for later response of ≥ 50% improvement in PANSS(0-6) Total score, early non-response most strongly predicted later non-response, demonstrating high specificity (74%) and high negative predictive value (80%). As had been seen in the treatment of patients with chronic schizophrenia, early non-response was a robust predictor of subsequent non-response in the treatment of patients with first-episode psychosis.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2004

Olanzapine treatment for tardive dyskinesia in schizophrenia patients: a prospective clinical trial with patients randomized to blinded dose reduction periods

Bruce J. Kinon; Dilip V. Jeste; Sara Kollack-Walker; Virginia L. Stauffer; Hong Liu-Seifert

BACKGROUND Tardive dyskinesia (TD) is a potentially persistent and disabling abnormal involuntary movement disorder. The aim of this 8-month study was to determine if olanzapine treatment could lead to a significant and persistent reduction in preexisting TD. METHODS Eligible schizophrenia patients met restricted Research Diagnosis criteria of TD requiring, in part, a rating of at least moderate severity (score > or = 3) in one or more of seven body regions on the Abnormal Involuntary Movement Scale (AIMS). Patients received olanzapine, 5-20 mg/day, for 8 months. During this period, they underwent one to two dose reduction periods under blinded conditions. Concurrent changes in TD, psychopathology, parkinsonism and akathisia were assessed with the AIMS, the Positive and Negative Syndrome Scale (PANSS), and the Simpson-Angus and Barnes Akathisia Scales, respectively. RESULTS A significant reduction in mean AIMS total score was demonstrated at endpoint (n = 92; p < 0.001) as well as at each visit (p < 0.001) and as early as Week 1 on olanzapine. Approximately 70% of patients no longer met the restricted Research Diagnostic criteria for persistent TD (RD-TD) after 8 months of treatment. No statistically significant rebound worsening of TD was found during either blinded drug reduction period. Significant improvement in psychopathology (p = 0.001) and parkinsonism (p < 0.001) was observed. CONCLUSIONS Improvement in the severity of preexisting TD was achieved with olanzapine and persisted throughout the 8-month study and during each dose reduction period. Overall improvement in clinical status suggests that olanzapine may be effective for the long-term management of schizophrenia patients with preexisting TD.

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Lei Chen

Eli Lilly and Company

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John M. Kane

Albert Einstein College of Medicine

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