Virginia L. Stauffer

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

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.

Medication nonadherence and treatment outcome in patients with schizophrenia or schizoaffective disorder with suboptimal prior response.

OBJECTIVE To examine the impact of medication nonadherence on treatment outcome in schizophrenia and potential risk factors for nonadherence. METHOD A post hoc analysis of a randomized, double-blind, 8-week, fixed-dose study comparing olanzapine 10, 20, and 40 mg/day for patients with schizophrenia or schizoaffective disorder (DSM-IV criteria) with suboptimal response to current treatment (N = 599) was conducted between September 12, 2003, and November 3, 2005, at 55 study centers in the United States. Nonadherence was defined as not taking medication as prescribed based on daily pill counts. Because there was no significant difference in nonadherence between dose groups, effects of nonadherence on efficacy and safety outcomes were examined using all 3 groups combined. Baseline demographics and symptom severity were investigated as potential risk factors for nonadherence. RESULTS During the 8-week study, 34.5% of patients were nonadherent at least once. Nonadherent patients had significantly less improvement compared to adherent patients as measured by change in Positive and Negative Syndrome Scale total score (-22.57 vs. -26.84, p = .002). Longer duration of nonadherence was associated with reduced likelihood of treatment response (odds ratio = 0.94, 95% CI = 0.90 to 0.99, p = .008). The early treatment discontinuation rate was higher in nonadherent compared to adherent patients (40.8% vs. 24.5%, p < .001). Adherent and nonadherent patients had comparable outcomes in most safety measures, except for weight change, for which adherent patients had greater weight gain than nonadherent patients (2.63 kg vs. 1.96 kg, p = .02). Greater depression severity at baseline (p = .01) and greater hostility level during the study were significant risk factors for nonadherence (p = .02). CONCLUSIONS Medication nonadherence had a significantly negative impact on treatment response, highlighting the importance of adherence to achieve satisfactory treatment outcome. Findings may also help clinicians identify patients at risk for nonadherence and utilize interventions to improve adherence. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00100776.

Standard and higher dose of olanzapine in patients with schizophrenia or schizoaffective disorder: A randomized, double-blind, fixed-dose study

Abstract The objective of this study was to assess the dose-response relationship of standard and higher doses of olanzapine in a randomized, double-blind, 8-week, fixed-dose study comparing olanzapine 10 (n = 199), 20 (n = 200), and 40 mg/d (n = 200) for patients with schizophrenia or schizoaffective disorder and suboptimal response to current treatment. Patients meeting criteria for antipsychotic treatment resistance were excluded. Dose-response relationship was assessed by linear regression analysis with log-transformed dose (independent variable) and Positive and Negative Syndrome Scale (PANSS) total score (dependent variable). There were no significant dose group differences in patients completing the study (overall, 67.8%). All dose groups showed statistically significant improvement in PANSS total scores from baseline to end point without significant dose-response relationship (P = 0.295). Post hoc analysis of response showed significant interaction between baseline PANSS and dose (P = 0.023), indicating better response at higher doses for patients with higher baseline PANSS. There was a significant dose response for mean change in weight (P = 0.003) with significant difference between the 10- and 40-mg-dose groups (P = 0.002; 1.9 [10 mg/d], 2.3 [20 mg/d], and 3.0 kg [40 mg/d]). There was a significant dose response for change in prolactin (P < 0.001) with a significant difference between each group (−10.5 [10 mg/d], −1.7 [20 mg/d], and 4.9 ng/mL [40 mg/d]; P ≤ 0.018). Over 8 weeks, non-treatment-resistant patients with schizophrenia or schizoaffective disorder responded to all 3 doses of olanzapine, without a statistically significant dose-response relationship, suggesting that for many patients with schizophrenia or schizoaffective disorder, particularly those who are mildly or moderately ill, 10 mg/d should be the initial dose of choice.

Pomaglumetad methionil: no significant difference as an adjunctive treatment for patients with prominent negative symptoms of schizophrenia compared to placebo.

This study tested whether treatment with pomaglumetad methionil (LY2140023 monohydrate), a metabotropic glutamate receptor 2/3 agonist compared with placebo (PBO), when added to a fixed-dose second-generation antipsychotic (SGA) demonstrated significantly greater reduction of negative symptoms, as assessed by the 16-item Negative Symptom Assessment scale (NSA-16), in patients with schizophrenia. This parallel-group, 16-week study enrolled adults with schizophrenia who were receiving standard of care (SOC) therapy, which included ≥3months treatment with one of four SGAs: aripiprazole, olanzapine, risperidone, or quetiapine. Patients received either 20mg of twice daily LY2140023 monohydrate (LY2140023) or concurrent PBO SGA. The primary efficacy measure was change from baseline to final visit in NSA-16 total score. Secondary measures included additional measures of efficacy, cognition, and assessments of safety. Of 352 patients screened, 167 were randomly assigned to treatment, and 110 patients completed the study. Patients treated with LY2140023 and SOC failed to demonstrate a statistically significant improvement over patients treated with PBO and SOC on NSA-16 total score at endpoint or at any point during the study (all p>0.131). Changes in secondary efficacy measures were not significantly different between groups at endpoint. With the exception of vomiting which was greater in the LY2140023 group, there were no statistically significant differences in safety and tolerability measures. This study found no benefit of adjunctive LY2140023 versus PBO for negative symptoms in patients with schizophrenia receiving treatment with SOC. LY2140023 was generally well-tolerated in these patients.

Acute dysphoric mania: treatment response to olanzapine versus placebo.

A substantial number of patients with mania have significant concomitant depressive features, and they may respond differently to mood stabilizers than patients with pure mania. This post-hoc analysis explored the response characteristics of olanzapine versus placebo in bipolar I manic patients with dysphoric and nondysphoric mania (differentiated by baseline Hamilton Depression Rating Scale [HAM-D] score of >20). Two similar, double-blind, randomized trials comparing olanzapine, 5–20 mg, to placebo were pooled for these analyses (N = 246). Mean changes in Young-Mania Rating Scale (Y-MRS) and HAM-D scores during 3 weeks of treatment were examined. Twenty-eight percent of patients had dysphoric mania (olanzapine, n = 33; placebo, n = 35). Among these patients, olanzapine-treated patients had greater improvement within 1 week than did placebo-treated patients on both mania ratings (Y-MRS: −9.7 vs. −3.0 points;p = 0.011) and depressive symptom ratings (HAM-D: −9.9 vs. −5.4 points;p = 0.025). Among those manic subjects without prominent depressive symptoms (olanzapine, n = 91; placebo, n = 87), mean Y-MRS improvement from baseline to endpoint with olanzapine (−11.5 points) versus placebo (−6.13 points) was comparable to the improvement seen with olanzapine versus placebo in the dysphoric mania subgroup (p = 0.476, test of interaction). In acutely ill manic patients with significant depressive symptoms, olanzapine demonstrated a broad spectrum of efficacy, effectively treating both manic and depressive symptoms. The magnitude of the antimanic response appears similar, regardless of baseline depressive features. Additional experience with putative mood stabilizers and atypical agents in mixed mania should include an exploration of their efficacy in treating both manic and depressive mood symptoms.

Dose Response and Atypical Antipsychotics in Schizophrenia

Based on information from clinical trials, both the efficacy and adverse effects of conventional antipsychotics in the treatment of schizophrenia are dose related. The overlapping nature of these dose-response profiles limits the use of these agents. Atypical antipsychotics provide greater relief across the comorbid symptom domains of schizophrenia, but dose-response studies and clinical experience have revealed that some of these drugs also have dose limitations. This article reviews the dose-response relationships of the atypical antipsychotics as presented predominantly in pivotal, randomised studies (double-blind and otherwise).Limited data indicate that clozapine shows dose-related efficacy up to 600 mg/ day in patients with treatment-resistant schizophrenia. However, higher dosages of clozapine may be associated with the risk of seizures. Risperidone demonstrates dose-related adverse events that compromise efficacy. The dose-response relationships for ziprasidone, quetiapine and aripiprazole are less well established. The efficacy of olanzapine appears to be dose related within the recommended dosage range of 10–20 mg/day, but clinical trials that have explored higher dosages suggest improved efficacy. Furthermore, the higher doses are not associated with a significantly increased incidence of adverse events.Further studies are clearly needed to fully characterise the dose-response relationships of atypical antipsychotics.

Olanzapine Plasma Concentrations After Treatment With 10, 20, and 40 mg/d in Patients With Schizophrenia: An Analysis of Correlations With Efficacy, Weight Gain, and Prolactin Concentration

Objectives of the study were to evaluate the relationship between olanzapine plasma concentrations and efficacy, prolactin, and weight and to assess effects of smoking, sex, and race on the pharmacokinetic characteristics of oral olanzapine up to 40 mg/d. Patients were randomly allocated to olanzapine 10, 20, or 40 mg/d for 8 weeks. Olanzapine concentrations in 634 samples from 380 patients were analyzed. Mean sample collection time was approximately 15 hours after dose for all groups. Mean olanzapine concentrations were 19.7 ± 11.4, 37.9 ± 22.8, and 74.5 ± 43.7 ng/mL for 10-, 20-, and 40-mg doses, respectively. Olanzapine concentration and Positive and Negative Syndrome Scale improvement were not significantly correlated. Change in both weight and prolactin showed significant dose response. Prolactin concentration was correlated with olanzapine concentration (r = 0.46, P < 0.001). No significant correlation between olanzapine concentration and weight change was observed. Olanzapine concentrations were lower in self-reported smokers (16.5 ± 9.6, 34.2 ± 20.8, and 60.9 ± 34.6 ng/mL) than in self-reported nonsmokers (25.6 ± 12.3, 43.4 ± 24.7, and 113.2 ± 44.0 ng/mL) for 10-, 20-, and 40-mg doses, respectively (P ≤ 0.022). In the 40-mg group only, African Americans had a lower mean olanzapine concentration than whites (65.6 ± 44.1 and 84.8 ± 44.1 ng/mL, respectively, P = 0.048). Women had numerically but not significantly higher mean olanzapine concentrations than men. In conclusion, olanzapine pharmacokinetics of doses up to 40 mg/d was generally consistent with prior findings in studies with fewer subjects and/or lower doses.

Candidate-gene association analysis of response to risperidone in African-American and white patients with schizophrenia

Clinical trial data were evaluated for the association between 22 single-nucleotide polymorphisms (SNPs) and response in acutely ill patients diagnosed with schizophrenia, schizoaffective disorder or schizophreniform disorder, who were treated with oral risperidone. All patients in the exploratory (78 African Americans) and validation (65 whites) data sets received risperidone 2–6 mg per day over 2–12 weeks. Two SNPs were found to have significant associations with response to risperidone over 2–12 weeks in both African-American and white patients and had a consistent direction of effect in both cohorts. Metabotropic glutamate receptor (GRM3) SNP, rs724226, was associated with a change in the positive and negative syndrome scale (PANSS) total response. Catechol-O-methyltransferase (COMT) SNP, rs165599, was moderately associated with a change in the PANSS Negative score. The greater prevalence of poor-responder GRM3 and COMT alleles in white versus African-American patients might have a clinical significance in evaluating the ethnic-specific response to risperidone.

The heterogeneity of antipsychotic response in the treatment of schizophrenia

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.

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

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.