No abstract

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 X20% 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; po001). Early response/nonresponse 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 ¼ 0.020) and in depressive symptoms (end point; p ¼ 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 treatmentemergent 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.

No abstract

During an agonistic encounter, subordinate male hamsters display defensive and submissive postures and show increased secretion of glucocorticoids, whereas dominant males do not. To determine whether specific neuronal pathways are activated during the behavioral and neuroendocrine responses of subordinate males, expression of c-fos mRNA within the brains of subordinate males was compared with the pattern in dominant males after fighting. After 1 week of handling, pairs of hamsters were either swapped between cages (handled control males), or were allowed to interact for 30 min [dominant (DOM) males and subordinate (SUB) males]. A second group of control animals that received no handling or social stimulation (unhandled control males) were also included. After testing, all animals were killed by decapitation, their brains were removed for c-fos in situ hybridization, and trunk blood was collected for analysis of plasma cortisol and corticosterone levels. Exposure of males to their partner's cage for 30 min resulted in increased expression of c-fos mRNA in multiple brain regions. In addition, fighting increased c-fos expression in the medial amygdaloid nucleus of both DOM and SUB males as well as having more selective effects. In DOM males, c-fos expression was elevated within the supraoptic nucleus of the hypothalamus. In SUB males, c-fos expression increased within a multitude of brain areas, including cingulate cortex, lateral septum, bed nucleus of the stria terminalis, medial preoptic area, several hypothalamic nuclei, central amygdaloid nucleus, amygdalohippocampal area, dorsal periaqueductal gray, dorsal raphe, cuneiform nucleus, and locus coeruleus. These findings are discussed in relation to neurocircuits associated with behavioral arousal and stress.

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.