BACKGROUND

Several clinical and research applications require an estimation of therapeutic dose equivalence across antipsychotic medications. Since the advent of the newer atypical antipsychotics, new dose equivalent estimations have been needed.

METHODS

The reported minimum effective dose was identified for each newer atypical antipsychotic medication and for haloperidol across all available fixed-dose placebo-controlled studies. Reported minimum effective dose equivalence ratios to haloperidol were then converted to chlorpromazine equivalents using the "2 mg of haloperidol equals 100 mg of chlorpromazine" convention.

METHODS

To identify the fixed-dose studies, the following sources were searched until June 2002: MEDLINE, the bibliographies of identified reports, published meta-analyses and reviews, Cochrane reviews, Freedom of Information Act material available from the Food and Drug Administration, and abstracts from several scientific meetings from 1997 to 2002.

RESULTS

Doses equivalent to 100 mg/day of chlorpromazine were 2 mg/day for risperidone, 5 mg/day for olanzapine, 75 mg/day for quetiapine, 60 mg/day for ziprasidone, and 7.5 mg/day for aripiprazole.

CONCLUSIONS

These equivalency estimates may be useful for clinical and research purposes. The source of the dose equivalency estimation is evidence-based and consistent across medication.

BACKGROUND

Cardiometabolic effects of second-generation antipsychotic medications are concerning but have not been sufficiently studied in pediatric and adolescent patients naive to antipsychotic medication.

OBJECTIVE

To study the association of second-generation antipsychotic medications with body composition and metabolic parameters in patients without prior antipsychotic medication exposure.

METHODS

Nonrandomized Second-Generation Antipsychotic Treatment Indications, Effectiveness and Tolerability in Youth (SATIETY) cohort study, conducted between December 2001 and September 2007 at semi-urban, tertiary care, academic inpatient and outpatient clinics in Queens, New York, with a catchment area of 4.5-million individuals. Of 505 youth aged 4 to 19 years with 1 week or less of antipsychotic medication exposure, 338 were enrolled (66.9%). Of these patients, 272 had at least 1 postbaseline assessment (80.5%), and 205 patients [corrected] completed the study (60.7%). Patients had mood spectrum (n = 130; 47.8%), schizophrenia spectrum (n = 82; 30.1%), and disruptive or aggressive behavior spectrum (n = 60; 22.1%) disorders. Fifteen patients who refused participation or were nonadherent served as a comparison group.

METHODS

Treatment with aripiprazole, olanzapine, quetiapine, or risperidone for 12 weeks.

METHODS

Weight gain and changes in lipid and metabolic parameters.

RESULTS

After a median of 10.8 weeks (interquartile range, 10.5-11.2 weeks) of treatment, weight increased by 8.5 kg (95% confidence interval [CI], 7.4 to 9.7 kg) with olanzapine (n = 45), by 6.1 kg (95% CI, 4.9 to 7.2 kg) with quetiapine (n = 36), by 5.3 kg (95% CI, 4.8 to 5.9 kg) with risperidone (n = 135), and by 4.4 kg (95% CI, 3.7 to 5.2 kg) with aripiprazole (n = 41) compared with the minimal weight change of 0.2 kg (95% CI, -1.0 to 1.4 kg) in the untreated comparison group (n = 15). With olanzapine and quetiapine, respectively, mean levels increased significantly for total cholesterol (15.6 mg/dL [95% CI, 6.9 to 24.3 mg/dL] P < .001 and 9.1 mg/dL [95% CI, 0.4 to 17.7 mg/dL] P = .046), triglycerides (24.3 mg/dL [95% CI, 9.8 to 38.9 mg/dL] P = .002 and 37.0 mg/dL [95% CI, 10.1 to 63.8 mg/dL] P = .01), non-high-density lipoprotein (HDL) cholesterol (16.8 mg/dL [95% CI, 9.3 to 24.3 mg/dL] P < .001 and 9.9 mg/dL [95% CI, 1.4 to 18.4 mg/dL] P = .03), and ratio of triglycerides to HDL cholesterol (0.6 [95% CI, 0.2 to 0.9] P = .002 and (1.2 [95% CI, 0.4 to 2.0] P = .004). With risperidone, triglycerides increased significantly (mean level, 9.7 mg/dL [95% CI, 0.5 to 19.0 mg/dL]; P = .04). Metabolic baseline-to-end-point changes were not significant with aripiprazole or in the untreated comparison group.

CONCLUSIONS

First-time second-generation antipsychotic medication use was associated with significant weight gain with each medication. Metabolic changes varied among the 4 antipsychotic medications.

Aripiprazole is the first next-generation atypical antipsychotic with a mechanism of action that differs from currently marketed typical and atypical antipsychotics. Aripiprazole displays properties of an agonist and antagonist in animal models of dopaminergic hypoactivity and hyperactivity, respectively. This study examined the interactions of aripiprazole with a single population of human D2 receptors to clarify further its pharmacologic properties. In membranes prepared from Chinese hamster ovary cells that express recombinant D2L receptors, aripiprazole bound with high affinity to both the G protein-coupled and uncoupled states of receptors. Aripiprazole potently activated D2 receptor-mediated inhibition of cAMP accumulation. Partial receptor inactivation using the alkylating agent N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) significantly reduced the maximum effect of aripiprazole on inhibition of cAMP accumulation. This effect was seen with concentrations of EEDQ that did not alter the maximal inhibitory effect of dopamine. Consistent with the expected effects of a partial agonist, increasing concentrations of aripiprazole blocked the action of dopamine with maximal blockade equal to the agonist effect of aripiprazole alone. The efficacy of aripiprazole relative to that of dopamine varied from 25% in cells that lacked spare receptors for dopamine to 90% in cells with receptor reserve. These results, together with previous studies demonstrating partial agonist activity at serotonin 5-hydroxytryptamine (5-HT)1A receptors and antagonist activity at 5-HT2A receptors, support the identification of aripiprazole as a dopamine-serotonin system stabilizer. The receptor activity profile may underlie the unique activity of aripiprazole in animals and its antipsychotic activity in humans.

Atypical antipsychotic drugs have revolutionized the treatment of schizophrenia and related disorders. The current clinically approved atypical antipsychotic drugs are characterized by having relatively low affinities for D(2)-dopamine receptors and relatively high affinities for 5-HT(2A) serotonin receptors (5-HT, 5-hydroxytryptamine (serotonin)). Aripiprazole (OPC-14597) is a novel atypical antipsychotic drug that is reported to be a high-affinity D(2)-dopamine receptor partial agonist. We now provide a comprehensive pharmacological profile of aripiprazole at a large number of cloned G protein-coupled receptors, transporters, and ion channels. These data reveal a number of interesting and potentially important molecular targets for which aripiprazole has affinity. Aripiprazole has highest affinity for h5-HT(2B)-, hD(2L)-, and hD(3)-dopamine receptors, but also has significant affinity (5-30 nM) for several other 5-HT receptors (5-HT(1A), 5-HT(2A), 5-HT(7)), as well as alpha(1A)-adrenergic and hH(1)-histamine receptors. Aripiprazole has less affinity (30-200 nM) for other G protein-coupled receptors, including the 5-HT(1D), 5-HT(2C), alpha(1B)-, alpha(2A)-, alpha(2B)-, alpha(2C)-, beta(1)-, and beta(2)-adrenergic, and H(3)-histamine receptors. Functionally, aripiprazole is an inverse agonist at 5-HT(2B) receptors and displays partial agonist actions at 5-HT(2A), 5-HT(2C), D(3), and D(4) receptors. Interestingly, we also discovered that the functional actions of aripiprazole at cloned human D(2)-dopamine receptors are cell-type selective, and that a range of actions (eg agonism, partial agonism, antagonism) at cloned D(2)-dopamine receptors are possible depending upon the cell type and function examined. This mixture of functional actions at D(2)-dopamine receptors is consistent with the hypothesis proposed by Lawler et al (1999) that aripiprazole has "functionally selective" actions. Taken together, our results support the hypothesis that the unique actions of aripiprazole in humans are likely a combination of "functionally selective" activation of D(2) (and possibly D(3))-dopamine receptors, coupled with important interactions with selected other biogenic amine receptors--particularly 5-HT receptor subtypes (5-HT(1A), 5-HT(2A)).

OBJECTIVE

Atypical antipsychotic medications are widely used to treat delusions, aggression, and agitation in people with Alzheimer disease (AD) and other dementia. Several clinical trials have not shown efficacy, and there have been concerns about adverse events. The objective of this study was to assess the evidence for efficacy and adverse events of atypicals for people with dementia.

METHODS

MEDLINE, the Cochrane Register of Controlled Trials, meetings, presentations, and information obtained from sponsors were used in this study. Published and unpublished randomized, placebo-controlled, double-blind, parallel-group trials in patients with AD or dementia of atypical antipsychotics marketed in the United States were studied. Clinical and trials characteristics, outcomes, and adverse events were extracted. Data were checked by a second reviewer. Fifteen trials including 16 contrasts of atypical antipsychotics with placebo met selection criteria: aripiprazole (k = 3), olanzapine (k = 5), quetiapine (k = 3), and risperidone (k = 5). A total of 3,353 patients were randomized to drug and 1,757 to placebo. Standard meta-analysis methods were used to summarize outcomes.

RESULTS

Quality of the reporting of trials varied. Efficacy on rating scales was observed by meta-analysis for aripiprazole and risperidone, but not for olanzapine. Response rates were frequently not reported. There were smaller effects for less severe dementia, outpatients, and patients selected for psychosis. Approximately one-third dropped out without overall differences between drug and placebo. Adverse events were mainly somnolence and urinary tract infection or incontinence across drugs, and extrapyramidal symptoms or abnormal gait with risperidone or olanzapine. Cognitive test scores worsened with drugs. There was no evidence for increased injury, falls, or syncope. There was a significant risk for cerebrovascular events, especially with risperidone; increased risk for death overall was reported elsewhere.

CONCLUSIONS

Small statistical effect sizes on symptom rating scales support the evidence for the efficacy of aripiprazole and risperidone. Incomplete reporting restricts estimates of response rates and clinical significance. Dropouts and adverse events further limit effectiveness. Atypicals should be considered within the context of medical need and the efficacy and safety of alternatives. Individual patient meta-analyses are needed to better assess clinical significance and effectiveness.

OBJECTIVE

The metabolic side effects of second-generation antipsychotics (SGA) are serious and have not been compared head to head in a meta-analysis. We conducted a meta-analysis of studies comparing the metabolic side effects of the following SGAs head-to-head: amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone, zotepine.

METHODS

We searched the register of the Cochrane schizophrenia group (last search May 2007), supplemented by MEDLINE and EMBASE (last search January 2009) for randomized, blinded studies comparing the above mentioned SGA in the treatment of schizophrenia or related disorders. At least three reviewers extracted the data independently. The primary outcome was weight change. We also assessed changes of cholesterol and glucose. The results were combined in a meta-analysis.

RESULTS

We included 48 studies with 105 relevant arms. Olanzapine produced more weight gain than all other second-generation antipsychotics except for clozapine where no difference was found. Clozapine produced more weight gain than risperidone, risperidone more than amisulpride, and sertindole more than risperidone. Olanzapine produced more cholesterol increase than aripiprazole, risperidone and ziprasidone. (No differences with amisulpride, clozapine and quetiapine were found). Quetiapine produced more cholesterol increase than risperidone and ziprasidone. Olanzapine produced more increase in glucose than amisulpride, aripiprazole, quetiapine, risperidone and ziprasidone; no difference was found with clozapine.

CONCLUSIONS

Some SGAs lead to substantially more metabolic side effects than other SGAs. When choosing an SGA for an individual patient these side effects with their potential cause of secondary diseases must be weighed against efficacy and characteristics of the individual patient.

OBJECTIVE

The objective of this study was to evaluate short-term efficacy and safety of aripiprazole in the treatment of irritability in children and adolescents with autistic disorder who were manifesting behaviors such as tantrums, aggression, self-injurious behavior, or a combination of these.

METHODS

This 8-week, double-blind, randomized, placebo-controlled, parallel-group study was conducted of children and adolescents (aged 6-17 years) with autistic disorder. Patients were randomly assigned (1:1) to flexibly dosed aripiprazole (target dosage: 5, 10, or 15 mg/day) or placebo. Efficacy outcome measures included the Aberrant Behavior Checklist irritability subscale and the Clinical Global Impression-Improvement score (CGI-I). Safety and tolerability were also assessed.

RESULTS

Ninety-eight patients were randomly assigned to receive placebo (n = 51) or aripiprazole (n = 47). Mean improvement in Aberrant Behavior Checklist irritability subscale score was significantly greater with aripiprazole than with placebo from week 1 through week 8. Aripiprazole demonstrated significantly greater global improvements than placebo, as assessed by the mean CGI-I score from week 1 through week 8; however, clinically significant residual symptoms may still persist for some patients. Discontinuation rates as a result of adverse events (AEs) were 10.6% for aripiprazole and 5.9% for placebo. Extrapyramidal symptom-related AE rates were 14.9% for aripiprazole and 8.0% for placebo. No serious AEs were reported. Mean weight gain was 2.0 kg on aripiprazole and 0.8 kg on placebo at week 8.

CONCLUSIONS

Aripiprazole was efficacious in children and adolescents with irritability associated with autistic disorder and was generally safe and well tolerated.

BACKGROUND

Aripiprazole is a dopamine D2 receptor partial agonist with partial agonist activity at serotonin 5HT1A receptors and antagonist activity at 5HT2A receptors. This multicenter trial examined the efficacy, safety, and tolerability of aripiprazole in patients with acute exacerbation of schizophrenia or schizoaffective disorder.

METHODS

In this 4-week double-blind study, 404 patients were randomized to 20 mg/d (n = 101) or 30 mg/d (n = 101) of aripiprazole, placebo (n = 103), or 6 mg/d of risperidone (n = 99). Efficacy assessments included Positive and Negative Syndrome Scale (PANSS) scores and Clinical Global Impression scores. Safety and tolerability evaluations included extrapyramidal symptoms and effects on weight, prolactin, and corrected QT (QTc) interval.

RESULTS

Aripiprazole (20 and 30 mg/d) and risperidone (6 mg/d) were significantly better than placebo on all efficacy measures. Separation from placebo occurred at week 1 for PANSS total and positive scores with aripiprazole and risperidone and for PANSS negative scores with aripiprazole. There were no significant differences between aripiprazole and placebo in mean change from baseline in the extrapyramidal symptom rating scales. Mean prolactin levels decreased with aripiprazole but significantly increased 5-fold with risperidone. Mean change in QTc interval did not differ significantly from placebo with any active treatment group. Aripiprazole and risperidone groups showed a similar low incidence of clinically significant weight gain.

CONCLUSIONS

Aripiprazole is effective, safe, and well tolerated for the positive and negative symptoms in schizophrenia and schizoaffective disorder. It is the first non-D2 receptor antagonist with clear antipsychotic effects and represents a novel treatment development for psychotic disorders.

BACKGROUND

Aripiprazole is an investigational agent for treating schizophrenia that has a novel pharmacologic profile. The present study investigated the efficacy, safety, and tolerability of aripiprazole and haloperidol compared with placebo.

METHODS

A 4-week, double-blind, randomized study, conducted at 36 U.S. centers between July 1997 and June 1998, compared aripiprazole (15 mg/day, 30 mg/day) to placebo, with haloperidol (10 mg/day) as an active control. Fixed doses of each agent were administered from day 1 throughout the study. A total of 414 patients with a primary DSM-IV diagnosis of schizophrenia or schizoaffective disorder were randomized. Efficacy measures included the Positive and Negative Syndrome Scale (PANSS) total, PANSS positive, PANSS negative, PANSS-derived Brief Psychiatric Rating Scale (BPRS) core, Clinical Global Impressions (CGI)-Severity of Illness, and mean CGI-Improvement scores. Safety and tolerability evaluations included extrapyramidal symptoms (EPS), weight gain, serum prolactin level, and QTc interval.

RESULTS

Both doses of aripiprazole and haloperidol, 10 mg, produced statistically significant (p < or = .05) improvements from baseline in PANSS total, PANSS positive, PANSS-derived BPRS core, and CGI-Severity scores and significantly lower CGI-Improvement scores at endpoint, compared with placebo. Aripiprazole, 15 mg, and haloperidol, 10 mg, significantly improved PANSS negative score compared with placebo. Both aripiprazole doses and haloperidol separated from placebo for PANSS total scores at week 2. Unlike haloperidol, aripiprazole was not associated with significant EPS or prolactin elevation at endpoint compared with placebo. There were no statistically significant differences in mean changes in body weight across the treatment groups versus placebo, and no patients receiving aripiprazole experienced clinically significant increases in QTc interval.

CONCLUSIONS

Aripiprazole, effective against positive and negative symptoms, is a safe and well-tolerated potential treatment for schizophrenia and schizoaffective disorder.

OBJECTIVE

To evaluate the short-term efficacy and safety of aripiprazole in the treatment of irritability in children and adolescents with autistic disorder.

METHODS

Two hundred eighteen children and adolescents (aged 6-17 years) with a diagnosis of autistic disorder, and with behaviors such as tantrums, aggression, self-injurious behavior, or a combination of these symptoms, were randomized 1:1:1:1 to aripiprazole (5, 10, or 15 mg/day) or placebo in this 8-week double-blind, randomized, placebo-controlled, parallel-group study. Efficacy was evaluated using the caregiver-rated Aberrant Behavior Checklist Irritability subscale (primary efficacy measure) and the clinician-rated Clinical Global Impressions-Improvement score. Safety and tolerability were also assessed.

RESULTS

At week 8, all aripiprazole doses produced significantly greater improvement than placebo in mean Aberrant Behavior Checklist Irritability subscale scores (5 mg/day, -12.4; 10 mg/day, -13.2; 15 mg/day, -14.4; versus placebo, -8.4; all p < .05). All aripiprazole doses demonstrated significantly greater improvements in mean Clinical Global Impressions-Improvement score than placebo at week 8. Discontinuation rates due to adverse events were as follows: placebo 7.7%, aripiprazole 5 mg/day 9.4%, 10 mg/day 13.6%, and 15 mg/day 7.4%. The most common adverse event leading to discontinuation was sedation. There were two serious adverse events: presyncope (5 mg/day) and aggression (10 mg/day). At week 8, mean weight change (last observation carried forward) was as follows: placebo +0.3 kg, aripiprazole 5 mg/day +1.3 kg, 10 mg/day +1.3 kg, and 15 mg/day +1.5 kg; all p < .05 versus placebo.

CONCLUSIONS

Aripiprazole was efficacious and generally safe and well tolerated in the treatment of children and adolescents with irritability associated with autistic disorder.

BACKGROUND

Aggression, agitation or psychosis occur in the majority of people with dementia at some point in the illness. There have been a number of trials of atypical antipsychotics to treat these symptoms over the last five years, and a systematic review is needed to evaluate the evidence in a balanced way.

OBJECTIVE

To determine whether evidence supports the use of atypical antipsychotics for the treatment of aggression, agitation and psychosis in people with Alzheimer's disease.

METHODS

The trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 7 December 2004 using the terms olanzapine, quetiapine, risperidone, clozapine, amisulpride, sertindole, zotepine, aripiprazole, ziprasidone. This Register contains articles from all major healthcare databases and many ongoing trials databases and is updated regularly.

METHODS

Randomised, placebo-controlled trials, with concealed allocation, where dementia and psychosis and/or aggression were assessed.

METHODS

1. Two reviewers extracted data from included trials2. Data were pooled where possible, and analysed using appropriate statistical methods3. Analysis included patients treated with an atypical antipsychotic, compared with placebo

RESULTS

Sixteen placebo controlled trials have been completed with atypical antipsychotics although only nine had sufficient data to contribute to a meta-analysis and only five have been published in full in peer reviewed journals. No trials of amisulpiride, sertindole or zotepine were identified which met the criteria for inclusion. The included trials led to the following results:1. There was a significant improvement in aggression with risperidone and olanzapine treatment compared to placebo.2. There was a significant improvement in psychosis amongst risperidone treated patients.3. Risperidone and olanzpaine treated patients had a significantly higher incidence of serious adverse cerebrovascular events (including stroke), extra-pyramidal side effects and other important adverse outcomes.4. There was a significant increase in drop-outs in risperidone (2 mg) and olanzapine (5-10 mg) treated patients.5. The data were insufficient to examine impact upon cognitive function.

CONCLUSIONS

Evidence suggests that risperidone and olanzapine are useful in reducing aggression and risperidone reduces psychosis, but both are associated with serious adverse cerebrovascular events and extra-pyramidal symptoms. Despite the modest efficacy, the significant increase in adverse events confirms that neither risperidone nor olanzapine should be used routinely to treat dementia patients with aggression or psychosis unless there is marked risk or severe distress. Although insufficient data were available from the considered trials, a meta-analysis of seventeen placebo controlled trials of atypical neuroleptics for the treatment of behavioural symptoms in people with dementia conducted by the Food and Drug Administration (using data not in the public domain) suggested a significant increase in mortality (OR 1.7).

Aripiprazole, 7-[4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy]-3,4-dihydro-2(1H)-quinolinone, a novel antipsychotic with partial agonist activity at dopamine D2 receptors, bound with high affinity to recombinant human 5-HT(1A) receptors (h5-HT(1A)) in Chinese hamster ovary cell membranes and displayed potent, partial agonism at 5-HT(1A) receptors in a guanosine-5'-O-(3-[(35)S]thio)-triphosphate ([(35)S]GTP gamma S)-binding assay that was blocked completely by a selective 5-HT(1A) receptor antagonist. An interaction with 5-HT(1A) receptors may contribute to the overall efficacy of aripiprazole against symptoms of schizophrenia, including anxiety, depression, cognitive and negative symptoms, and to its favorable side-effect profile. Combined with previous studies demonstrating the potent partial agonism of aripiprazole at dopamine D2 receptors, this study suggests aripiprazole is the first dopamine-serotonin system stabilizer.

OPC-14597 {aripiprazole; 7-(-4(4-(2,3-dichlorophenyl)-1-piperazinyl) butyloxy)-3,4-dihydro-2(1H)-quinolinone} is a novel candidate antipsychotic that has high affinity for striatal dopamine D2-like receptors, but causes few extrapyramidal effects. These studies characterized the molecular pharmacology of OPC-14597, DM-1451 (its major rodent metabolite), and the related quinolinone derivative OPC-4392 at each of the cloned dopamine receptors, and at serotonin 5HT6 and 5HT7 receptors. All three compounds exhibited highest affinity for D2L and D2S receptors relative to the other cloned receptors examined. Both OPC-4392 and OPC-14597 demonstrated dual agonist/antagonist actions at D2L receptors, although the metabolite DM-1451 behaved as a pure antagonist. These data suggest that clinical atypicality can occur with drugs that exhibit selectivity for D2L/D2S rather than D3 or D4 receptors, and raise the possibility that the unusual profile of OPC-14597 in vivo (presynaptic agonist and postsynaptic antagonist) may reflect different functional consequences of this compound interacting with a single dopamine receptor subtype (D2) in distinct cellular locales.

OBJECTIVE

The authors compared the efficacy and safety of aripiprazole, a novel antipsychotic, to placebo for treatment of patients in an acute manic or mixed episode of bipolar disorder.

METHODS

This 3-week, multicenter, double-blind study randomly assigned 262 bipolar disorder patients in an acute manic or mixed episode to aripiprazole, 30 mg/day (reduced to 15 mg/day if needed for tolerability), or placebo. Patients remained hospitalized for at least 2 of the weeks. The primary efficacy measure was mean change from baseline in total score on the Young Mania Rating Scale; response was defined as a decrease in score of>> or =50%.

RESULTS

Aripiprazole produced statistically significant mean improvements in total score on the Young Mania Rating Scale compared with placebo (-8.2 versus -3.4, respectively) and produced a significantly higher response rate (40% versus 19%). For key efficacy variables (response per Young Mania Rating Scale; Clinical Global Impression-Bipolar Version scores for severity of illness [mania] and change from preceding phase [mania]), aripiprazole separated from placebo by day 4. The completion rate was significantly higher with aripiprazole than with placebo (42% versus 21%). Discontinuations due to adverse events did not differ significantly between the aripiprazole and placebo groups. There were no significant changes in body weight versus placebo, and aripiprazole was not associated with elevated serum prolactin or QTc prolongation.

CONCLUSIONS

Aripiprazole had significantly greater efficacy than placebo for the treatment of bipolar disorder patients in acute manic or mixed episodes and was safe and well tolerated in this randomized controlled trial.

Aripiprazole is a novel antipsychotic with a unique mechanism of action. Presented here is a pooled analysis of safety and tolerability data from all completed short-term, placebo-controlled trials in schizophrenia from the aripiprazole clinical development program. Data were analyzed from five 4- to 6-week double-blind multicenter studies of patients hospitalized with acute relapse of schizophrenia or schizoaffective disorder randomized to aripiprazole (n=932), placebo (n=416), or haloperidol (n=201). Daily aripiprazole doses ranged from 2 to 30 mg. Safety assessments included adverse event (AE) reports, EPS scales, ECGs, weight, and prolactin, glucose and cholesterol levels. Aripiprazole was well tolerated, with similar AE incidence rates to placebo, and lower rates than haloperidol for akathisia, extrapyramidal syndrome and somnolence. Objective EPS assessments demonstrated no significant differences between aripiprazole and placebo on Simpson-Angus Scale (SAS) scores, no dose-dependent effects on Barnes Akathisia scores, and significant reductions in Abnormal Involuntary Movement Scale (AIMS) scores from baseline vs. placebo (p</=0.01). Haloperidol showed increased SAS and Barnes Akathisia scores over placebo (p</=0.01). There was minimal mean weight change with aripiprazole (+0.71 kg) and haloperidol (+0.56 kg), and a lack of QT(c) prolongation. Serum prolactin increased with haloperidol, but not aripiprazole. In conclusion, aripiprazole shows a favorable safety and tolerability profile with low potential for EPS, weight gain, prolactin elevation, QT(c) prolongation, and sedation. Aripiprazole's safety profile may offer benefits in schizophrenia treatment.

OBJECTIVE

To assess the efficacy and safety of aripiprazole versus placebo as adjunctive treatment to standard antidepressant therapy (ADT) in patients with major depressive disorder (MDD) who showed an incomplete response to 1 prospective and 1 to 3 historical courses of ADT within the current episode.

METHODS

The study comprised a 7- to 28-day screening phase, an 8-week prospective treatment phase, and a 6-week double-blind treatment phase. Patients with DSM-IV-TR-defined MDD were enrolled between June 16, 2004, and April 27, 2006. During prospective treatment, patients received ADT: escitalopram, fluoxetine, paroxetine controlled-release, sertraline, or venlafaxine extended-release, each with single-blind, adjunctive placebo. Incomplete responders continued ADT and were randomly assigned to double-blind, adjunctive placebo or adjunctive aripiprazole (2-15 mg/day with fluoxetine or paroxetine; 2-20 mg/day with all others). The primary efficacy endpoint was the mean change from end of prospective treatment to end of double-blind treatment (week 14, last observation carried forward) in Montgomery-Asberg Depression Rating Scale (MADRS) total score (analysis of covariance).

RESULTS

A total of 178 patients were randomly assigned to adjunctive placebo and 184 to adjunctive aripiprazole. Baseline demographics were similar between groups (mean MADRS total score of 26.0). Mean change in MADRS total score was significantly greater with adjunctive aripiprazole (-8.8) than adjunctive placebo (-5.8; p < .001). Adverse events (AEs) that occurred in>> or = 10% of patients with adjunctive placebo or adjunctive aripiprazole were akathisia (4.5% vs. 23.1%), headache (10.8% vs. 6.0%), and restlessness (3.4% vs. 14.3%). Discontinuations due to AEs were low with adjunctive placebo (1.7%) and adjunctive aripiprazole (2.2%); only 1 adjunctive aripiprazole-treated patient discontinued due to akathisia.

CONCLUSIONS

In patients with MDD who showed an incomplete response to ADT, adjunctive aripiprazole was efficacious and well tolerated.

BACKGROUND

ClinicalTrials.gov identifier NCT00095823.

BACKGROUND

As many as 1 in every 110 children in the United States has an autism spectrum disorder (ASD). Many medical treatments for ASDs have been proposed and studied, but there is currently no consensus regarding which interventions are most effective.

OBJECTIVE

To systematically review evidence regarding medical treatments for children aged 12 years and younger with ASDs.

METHODS

We searched the Medline, PsycInfo, and ERIC (Education Resources Information Center) databases from 2000 to May 2010, regulatory data for approved medications, and reference lists of included articles. Two reviewers independently assessed each study against predetermined inclusion/exclusion criteria. Studies of secretin were not included in this review. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes and assigned overall quality and strength-of-evidence ratings on the basis of predetermined criteria.

RESULTS

Evidence supports the benefit of risperidone and aripiprazole for challenging and repetitive behaviors in children with ASDs. Evidence also supports significant adverse effects of these medications. Insufficient strength of evidence is present to evaluate the benefits or adverse effects for any other medical treatments for ASDs, including serotonin-reuptake inhibitors and stimulant medications.

CONCLUSIONS

Although many children with ASDs are currently treated with medical interventions, strikingly little evidence exists to support benefit for most treatments. Risperidone and aripiprazole have shown benefit for challenging and repetitive behaviors, but associated adverse effects limit their use to patients with severe impairment or risk of injury.

Nonresponse to one or more antidepressants is common and an important public health problem. This study evaluated the efficacy and safety of adjunctive aripiprazole or placebo to standard antidepressant therapy (ADT) in patients with major depressive disorder who showed an inadequate response to at least 1 and up to 3 historical and 1 additional prospective ADT. The study comprised a 7-28-day screening, an 8-week prospective treatment, and a 6-week randomization phase. During prospective treatment, patients experiencing a major depressive episode (17-item Hamilton Rating Scale for Depression total score>> or = 18) received single-blind adjunctive placebo plus clinicians' choice of ADT (escitalopram, fluoxetine, paroxetine controlled-release, sertraline, or venlafaxine extended-release). Subjects with inadequate response were randomized to adjunctive placebo (n = 190) or adjunctive aripiprazole (n = 191) (starting dose 5 mg/d, dose adjustments 2-20 mg/d, mean end-point dose of 11.0 mg/d). The primary efficacy endpoint was the mean change in Montgomery-Asberg Depression Rating Scale total score from end of prospective treatment phase to end of randomized treatment phase (last observation carried forward). Mean change in Montgomery-Asberg Depression Rating Scale total score was significantly greater with adjunctive aripiprazole than placebo (-8.5 vs -5.7; P = 0.001). Remission rates were significantly greater with adjunctive aripiprazole than placebo (25.4% vs 15.2%; P = 0.016) as were response rates (32.4% vs 17.4%; P < 0.001). Adverse events occurring in 10% of patients or more with adjunctive placebo or aripiprazole were akathisia (4.2% vs 25.9%), headache (10.5% vs 9.0%), and fatigue (3.7% vs 10.1%). Incidence of adverse events leading to discontinuation was low (adjunctive placebo [1.1%] vs adjunctive aripiprazole [3.7%]). Aripiprazole is an effective and safe adjunctive therapy as demonstrated in this short-term study for patients who are nonresponsive to standard ADT.

Aripiprazole is a novel atypical antipsychotic for the treatment of schizophrenia. It is a D2 receptor partial agonist with partial agonist activity at 5-HT1A receptors and antagonist activity at 5-HT2A receptors. The long-term efficacy and safety of aripiprazole (30 mg/d) relative to haloperidol (10 mg/d) were investigated in two 52-wk, randomized, double-blind, multicentre studies (using similar protocols which were prospectively identified to be pooled for analysis) in 1294 patients in acute relapse with a diagnosis of chronic schizophrenia and who had previously responded to antipsychotic medications. Aripiprazole demonstrated long-term efficacy that was comparable or superior to haloperidol across all symptoms measures, including significantly greater improvements for PANSS negative subscale scores and MADRS total score (p<0.05). The time to discontinuation for any reason was significantly greater with aripiprazole than with haloperidol (p=0.0001). Time to discontinuation due to adverse events or lack of efficacy was significantly greater with aripiprazole than with haloperidol (p=0.0001). Aripiprazole was associated with significantly lower scores on all extrapyramidal symptoms assessments than haloperidol (p<0.001). In summary, aripiprazole demonstrated efficacy equivalent or superior to haloperidol with associated benefits for safety and tolerability. Aripiprazole represents a promising new option for the long-term treatment of schizophrenia.

BACKGROUND

Recently approved for the treatment of schizophrenia, aripiprazole represents the sixth second-generation antipsychotic (SGA) introduced to the US market. Aripiprazole is considered a partial dopaminergic agonist, acting on both postsynaptic dopamine(2) receptors and presynaptic autoreceptors, in addition to displaying partial agonism at serotonin(1A) receptors and antagonism at serotonin(2A) receptors.

OBJECTIVE

The aim of this study was to comprehensively review all available literature regarding the mechanism of action, pharmacokinetics, clinical efficacy, and adverse effects of aripiprazole.

METHODS

Relevant data were collected using MEDLINE and International Pharmaceutical Abstracts searches with the terms aripiprazole and OPC-14597 and with no limitations on year. Abstracts and posters presented at national and international scientific meetings were also reviewed.

RESULTS

Aripiprazole exhibits linear pharmacokinetics and is administered once daily. In multiple clinical trials, aripiprazole was effective in significantly reducing symptomatology associated with schizophrenia-related disorders compared with placebo (P < 0.05). Dosages>> or =15 mg/d more consistently produced significant reductions from baseline of Positive and Negative Syndrome Scale total scores (P < 0.05) and were more likely to elicit a response than smaller dosages. Effects observed were comparable to those seen with risperidone and haloperidol, which were also significantly more effective than placebo (P < or = 0.05). Aripiprazole exhibited a favorable safety and tolerability profile, with a low propensity to cause extrapyramidal symptoms, weight gain, cardiovascular abnormalities, hyperprolactinemia, hypercholesterolemia, or glucose dysregulation.

CONCLUSIONS

Aripiprazole represents a well-tolerated and effective addition to the antipsychotic armamentarium. However, definitive advantages associated with dopamine partial agonism have yet to be determined. Long-term, head-to-head comparisons with other SGAs are needed to establish the effects of chronic administration and the relative safety and efficacy of aripiprazole.

Aripiprazole (OPC 14597) is an antipsychotic drug that has high affinity for dopamine D2 and D3 receptors and the dopamine autoreceptor. It is being developed for treatment of patients with schizophrenia. The purpose of this study was to determine whether a dose response following graduated doses of aripiprazole could be quantified and correlated with its occupancy of the D2 and D3 dopamine receptors in the brain of living humans. Dopamine D2 and D3 receptor occupancy in fifteen normal male human brains was measured using positron emission tomography (PET) with [11C]raclopride. PET studies were performed before and after two weeks of administration of aripiprazole. The dopamine D2 receptor occupancy was quantified with two kinetic modeling methods without using a blood input function. Administration of aripiprazole for 14 days resulted in a dose-dependent receptor occupancy between 40 - 95% after the administration of 0.5mg, 1 mg, 2 mg, 10 mg, and 30 mg per day. These results suggest that an adequate occupancy can be obtained, and this may be useful to predict an appropriate therapeutic dose for an individual patient. Interestingly, even at striatal D2 receptor occupancy values above 90%, which occurred with the higher doses, extrapyramidal side effects (EPS) were not observed. This underlines aripiprazole's unique mechanism of action as a partial dopamine receptor agonist, which might become a novel principle in the treatment of schizophrenia.

The effects of 7-(4-[4-(2,3-dichlorophenyl)-1-piperazinyl]butyloxy)-3,4-dihydro-2 (1H)- quinolinone (OPC-14597), a derivative of the dopamine (DA) autoreceptor agonist 7-(3-[4-(2,3-dimethylphenyl)piperazinyl]propoxy)-2(1H)-quinolinone (OPC-4392), on DA receptors were biochemically and behaviorally studied and compared with those of OPC-4392. Both OPC-14597 and OPC-4392 inhibited reserpine- and gamma-butyrolactone (GBL)-induced increase in tyrosine hydroxylase activity in the mouse and rat brain. The effects of OPC-14597 were comparable to those of OPC-4392 and were completely antagonized by haloperidol. OPC-14597, unlike apomorphine, did not evoke postsynaptic DA receptor-stimulating behavioral signs such as hyperlocomotion in the reserpinized mice and contralateral rotation in rats with unilateral striatal 6-hydroxydopamine lesions. Both OPC-14597 and OPC-4392 inhibited such apomorphine-induced postsynaptic behavioral changes as stereotypy and hyperlocomotion in mice and rats and rotation in rats with unilateral striatal kainic acid lesions. The anti-apomorphine effects of OPC-14597 were about 30 to 140 times greater than those of OPC-4392 and were observed at doses that inhibit the increases in tyrosine hydroxylase activity. The affinities of OPC-14597 for 3H-spiperone-labeled D2 receptors in the rat frontal cortex, limbic forebrain and striatum were higher than those of OPC-4392. These results suggest that OPC-14597 is a unique antipsychotic drug candidate, being a DA autoreceptor agonist that has a stronger postsynaptic D2 receptor antagonistic activity than that of OPC-4392.

OBJECTIVE

Aripiprazole is a dopamine partial agonist approved for use in adults for short- and long-term treatment of schizophrenia and bipolar disorder. This study was designed to examine the acute efficacy, safety, and tolerability of aripiprazole for adolescents with schizophrenia.

METHODS

This was a 6-week multicenter, double-blind, randomized, placebo-controlled trial. Subjects 13 to 17 years old with a DSM-IV diagnosis of schizophrenia and a Positive and Negative Syndrome Scale (PANSS) total score of 70 or more were randomly assigned (1:1:1 ratio) to placebo or 10 or 30 mg/day of aripiprazole. The primary endpoint was mean change from baseline to endpoint (last observation carried forward) in PANSS total score. Assessments of safety and tolerability included spontaneously reported adverse events, extrapyramidal symptom scores, serum prolactin concentration, body weight, and metabolic measures.

RESULTS

Of 302 patients, 85% completed the 6-week study. The mean baseline PANSS score was 94.1. At the end of the study, both aripiprazole doses showed statistically significant differences from placebo in reduction in PANSS total score. Adverse events occurring in more than 5% of either aripiprazole group and with a combined incidence at least twice the rate for placebo were extrapyramidal disorder, somnolence, and tremor. Mean changes in prolactin were -8.45, -11.93, and -15.14 ng/ml for placebo and 10 mg and 30 mg of aripirazole, respectively. Mean body weight changes were -0.8, 0.0, and 0.2 kg for placebo and 10 mg and 30 mg of aripiprazole, respectively.

CONCLUSIONS

Both 10- and 30-mg/day doses of aripiprazole were superior to placebo in the acute treatment of adolescents with schizophrenia. Aripiprazole was generally well tolerated.

BACKGROUND

Aripiprazole is a novel antipsychotic for the management of schizophrenia. This study investigated the efficacy, safety, and tolerability of aripiprazole in preventing relapse in adult chronic schizophrenia patients experiencing ongoing stable symptomatology.

METHODS

In this 26-week, randomized, double-blind, placebo-controlled, parallel-group, multi-center study, 310 patients with DSM-IV schizophrenia (mean Positive and Negative Syndrome Scale [PANSS] total score = 82) were randomly assigned to receive a once-daily fixed dose of aripiprazole, 15 mg, or placebo. The primary outcome measure was time to relapse following randomization. Secondary objectives were to assess the efficacy, safety, and tolerability of aripiprazole, 15 mg, compared with placebo, in the study population. The study was conducted between Dec. 21, 2000, and Aug. 20, 2001.

RESULTS

The time to relapse following randomization was significantly (p < .001) longer for aripiprazole compared with placebo. More patients relapsed with placebo (N = 85; 57%) than aripiprazole (N = 50; 34%); the relative risk of relapse for the aripiprazole group was 0.59 (p < .001). Aripiprazole was significantly superior to placebo from baseline to endpoint in PANSS total, PANSS positive, PANSS-derived Brief Psychiatric Rating Scale, and Clinical Global Impressions-Severity of Illness scale (CGI-S) scores and demonstrated significantly better mean Clinical Global Impressions-Global Improvement scale scores (p < or = .01 for all comparisons except CGI-S: .01 < p < or = .05). Aripiprazole was well tolerated, with no evidence of marked sedation and no evidence of hyperprolactinemia or prolonged heart rate-corrected QT interval (QTc). Extrapyramidal symptoms were comparable in the aripiprazole and placebo groups. Modest mean weight loss at endpoint was evident in both groups.

CONCLUSIONS

Aripiprazole, 15 mg once daily, is an effective, well-tolerated treatment for prevention of relapse in patients with chronic, stable schizophrenia.