M. Patricia Ball

A randomized clinical trial of MK-0777 for the treatment of cognitive impairments in people with schizophrenia.

BACKGROUND In a previous pilot study, MK-0777--a γ-aminobutyric acid (GABA)(A) α2/α3 partial agonist--was reported to improve delayed memory and cognitive measures of prefrontal cortical function in people with schizophrenia. The current study was designed to further examine the efficacy and safety of MK-0777 for the treatment of cognitive impairments in schizophrenia. METHODS Sixty people with DSM-IV schizophrenia entered a 4-week, multi-center, double-blind, placebo-controlled, randomized clinical trial. Participants were randomized to: MK-0777 3 mg b.i.d. (n = 18); MK-0777 8 mg b.i.d. (n = 21); or placebo (n = 21). Participants were clinically stable. The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery, AX-Continuous Performance Test, and N-Back were used to assess cognition. The University of California San Diego (UCSD) Performance Based Skills Assessment-2 and the Schizophrenia Cognition Rating Scale assessed functional capacity and served as functional outcome coprimary measures. RESULTS There were no significant group differences on the primary outcome measure, the MATRICS Consensus Cognitive Battery composite score. Secondary analyses suggested that participants randomized to placebo performed significantly better on visual memory and reasoning/problem-solving tests than participants assigned to either MK-0777 dose. There were no significant group differences on the AX-Continuous Performance Test or N-Back d prime scores or UCSD Performance-Based Skills Assessment-2 and Schizophrenia Cognition Rating Scale total scores. In general, MK-0777 was well-tolerated with minimal side effects. CONCLUSIONS The study results suggest that MK-0777 has little benefit for cognitive impairments in people with schizophrenia. The GABA(A) receptor remains a promising target, but a more potent partial agonist with greater intrinsic activity at the GABA(A) α2 site might be needed for cognitive enhancement in schizophrenia.

Effect of the neuroprotective peptide davunetide (AL-108) on cognition and functional capacity in schizophrenia.

BACKGROUND Cognitive dysfunction is a key predictor of functional disability in schizophrenia. Davunetide (AL-108, NAP) is an intranasally administered peptide currently being developed for treatment of Alzheimers disease and related disorders. This study investigates effects of davunetide on cognition in schizophrenia. METHOD Sixty-three subjects with schizophrenia received davunetide at one of two different doses (5, 30 mg) or placebo for 12 weeks in a multicenter, double-blind, parallel-group randomized clinical trial. The MATRICS Consensus Cognitive Battery (MCCB) assessed cognitive effects. The UCSD Performance-based Skills Assessment (UPSA) and the Schizophrenia Cognition Rating Scale (SCoRS) assessed functional capacity. Subjects continued their current antipsychotic treatment during the trial. RESULTS There were no significant differences in MCCB change between davunetide and placebo over the three treatment arms (p=.45). Estimated effect-size (d) values were .34 and .21 favoring the 5 and 30 mg doses vs. placebo, respectively. For UPSA, there was a significant main effect of treatment across study arms (p=.048). Between-group effect size (d) values were.74 and .48, favoring the 5 and 30 mg doses, respectively. No significant effects were observed on the SCoRS or on symptom ratings. No significant side effects or adverse events were observed. CONCLUSION Davunetide was well tolerated. Effects of davunetide on MCCB-rated cognition were not significant relative to placebo. In contrast, a significant beneficial effect was detected for the UPSA. Based upon effect-size considerations, sample sizes of at least 45-50 subjects/group would be required to obtain significant effects on both MCCB and UPSA, providing guidance for continued clinical development in schizophrenia.

Effects of the Cannabinoid-1 Receptor Antagonist Rimonabant on Psychiatric Symptoms in Overweight People With Schizophrenia: A Randomized, Double-Blind, Pilot Study

Weight gain is a major adverse effect of several second-generation antipsychotic medications. Rimonabant is a cannabinoid-1 receptor antagonist that promotes weight loss in the general population. We conducted a 16-week, double-blind, placebo-controlled study of rimonabant (20 mg/d) in people with schizophrenia or schizoaffective disorder, based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, who were clinically stable on second-generation antipsychotics. Participants had a body mass index of 27 kg/m2 or higher with hyperlipidemia or body mass index of 30 kg/m2 or higher, and no current substance abuse/dependence (except nicotine), more than weekly cannabis use, or recent depressive symptoms/suicidality. An exercise and dietary counseling group was offered weekly. Target enrollment was 60; the trial was terminated early because of withdrawal of rimonabant from the European market. Fifteen participants were randomized (7 rimonabant, 8 placebo); 5 completed in each group. Rimonabant was associated with a greater reduction in Brief Psychiatric Rating Scale total score versus placebo (mean ± SE difference, −1.9 ± 0.8, P = 0.02), driven by differences in the Brief Psychiatric Rating Scale anxiety/depression (−1.4 ± 0.35, P = 0.0004) and hostility (−0.7 ± 0.3, P = 0.02) factors. Group differences were not significant for the Calgary Depression Scale total score (P = 0.24), Scale for the Assessment of Negative Symptoms total score (P = 0.13), weight, blood pressure, or fasting lipids or glucose. Rimonabant was well tolerated with no significant adverse events. No significant weight loss, metabolic effects, or adverse psychiatric effects were associated with the cannabinoid-1 receptor antagonist rimonabant in this small sample of people with schizophrenia. The endocannabinoid system remains a promising target for pharmacotherapy of schizophrenia and obesity.

Adjunctive risperidone for partially responsive people with schizophrenia treated with clozapine.

The large numbers of partial clozapine responders represent a major therapeutic challenge. Unfortunately, there are no clear data to support how best to treat these patients. This study examines the efficacy and safety of adjunctive risperidone in a well-defined treatment-resistant population optimally treated with clozapine. A total of 69 inpatients and outpatients with DSM-IV schizophrenia or schizoaffective disorder entered a 16-week double-blind, placebo-controlled, randomized clinical trial. Of them, 33 participants were randomized to risperidone and 36 were randomized to placebo. There was no significant group difference in the predefined response criteria. There were modest group differences for Brief Psychiatric Rating Scale (BPRS) positive symptoms, which were significant in the completer analysis (F=5.70; df=1, 70.3; p=0.02; ES=0.27) but not the intent-to-treat (ITT) analyses (F=3.01; df=1, 77.5; p=0.09; ES=0.19). A similar pattern was found for the BPRS total score, with the completer analysis showing a significant improvement in the risperidone group (F=5.21; df=1, 64.9; p=0.03; ES=0.27), whereas the ITT analysis was not significant (F=3.52; df=1, 71.3; p=0.06; ES=0.22). In addition, there was a small, but significant, group difference for negative symptoms, as measured by the SANS total score, which favored the risperidone group (F=5.67; df=1, 78.7; p=0.02; ES=0.24). There were no significant group differences on safety measures, including neuropsychological test and extrapyramidal symptom scores. A significant elevation of prolactin in the risperidone group was observed. The study results suggest that adjunctive risperidone may have a modest benefit for treatment-resistant clozapine patients. The study results are discussed in the context of previous double-blind studies of adjunctive risperidone. (clinicaltrials.gov, trial number: NCT00056498).

Exercise Program Adherence Using a 5-Kilometer (5K) Event as an Achievable Goal in People With Schizophrenia

People with schizophrenia have a higher prevalence of obesity than the general population. Many people with this illness struggle with weight gain, due, in part, to medications and other factors that act as obstacles to exercise and healthy eating. Several studies have shown the benefits of behavioral weight loss programs targeting eating and/or exercise in people with schizophrenia. Fewer studies have used competitive events as a goal for an exercise program. The current study tested the feasibility of preparing, using an exercise program, for a 5-kilometer (5K) event in people with schizophrenia. The exercise program was a 10-week training program consisting of three supervised walking/jogging sessions per week and a weekly educational meeting on healthy behaviors. Almost 65% (11/17) of the subjects participated in all of the training sessions, and 82% (14/17) participated in the 5K event. Participants did not gain a significant amount of weight during the exercise program (median weight change = 0.7 kg; 25th percentile 0.5, 75th percentile 3.9, p = .10). This study suggests that using an achievable goal, such as a 5K event, promotes adherence to an exercise program and is feasible in a population of people with chronic schizophrenia.

A Phase II study of a histamine H3 receptor antagonist GSK239512 for cognitive impairment in stable schizophrenia subjects on antipsychotic therapy

This Phase II exploratory study assessed GSK239512, a brain penetrant histamine H₃ receptor antagonist, versus placebo on cognitive impairment in 50 stable outpatients with schizophrenia. Subjects were randomized to placebo or GSK239512 for 7 weeks (4 weeks titration). GSK239512 was associated with a small positive effect size (ES) on the CogState Schizophrenia Battery (CSSB) Composite Score (ES=0.29, CI=-0.40, 0.99) relative to placebo (primary endpoint). GSK239512s ES on CSSB domains were generally positive or neutral except Processing Speed, which favored placebo (ES=-0.46). Effects on the MATRICS Consensus Cognitive Battery were mostly neutral or favored placebo. GSK239512 was generally well tolerated with an adverse event profile consistent with the known class pharmacology. There was no evidence of overall beneficial effects of GSK239512 for CIAS in this population.