Aripiprazole in the Treatment??of Schizophrenia

Aripiprazole-induced obsessive-compulsive symptoms

Aripiprazole is a novel antipsychotic with a unique pharmacological profile as a dopamine partial agonist. It is indicated for treatment of schizophrenia and bipolar disorder. This new antipsychotic has low rate of extrapyramidal side effects, metabolic changes and no significant adverse effect on serum prolactin concentration. In addition,it is not associated with significant weight gain like other atypical antipsychotics. As a reason, when other antipsychotics cause these adverse events, it's not uncommon to switch to Aripiprazole. Obsessive compulsive symptoms have been untoward sequel of a few second-generation antipsychotics. Among the second generation antipsychotics Clozapine, Olanzapine, and Risperidone are the most prominent agents associated with these sequelae, according to case reports. More recently, a handful of case reports indicated development of Obsessive-compulsive symptoms with Aripiprazole. We report a case that exhibited similar unexpected adverse effects after administration of Aripiprazole. Keywords: Aripiprazole, Second generation antipsychotics, Obsessive-compulsive symptoms (OCS).

Interaction of pain and chronic inflammation

Rheumatic diseases are characterized by chronic inflammation of synovial joints and are often associated with persistent pain and increased pain sensitivity. The inflammatory process is a complex cascade of events involving several mediators, which can lead to a chronic condition of pain. Inflammation can stimulate angiogenesis, and angiogenesis can facilitate inflammation. Inflammatory pain arises from tissue damage via the sensitization of pain receptors (nociceptors). The main peripheral mechanism underlying nociceptive pain is a change in the activity of the nociceptors located in the affected anatomical structures (joints, tendons, and ligaments), which renders them more sensitive to normally painful stimuli (hyperalgesia) or normally non-painful stimuli (allodynia). Neuroimmune interaction has been considered to play an essential role in rheumatic disease. Neurogenic inflammation, which influences normal central nervous system signaling, leads to insufficient signaling/bioavailability of various cytokines. These central mechanisms play an important role in the increased pain sensitivity following inflammation and are responsible for the development of secondary hyperalgesia in regions beyond the injured tissue. Reduction of pain in rheumatic disease requires familiarity with various pain mechanisms.

Effects of aripiprazole on circadian prolactin secretion related to pharmacogenetics in healthy volunteers

Aripiprazole treatment in schizophrenic patients was previously associated with lower or normalized prolactin levels. Genetic variants in cytochrome P450 (CYP) (CYP2D6), dopamine receptor (DRD2, DRD3) and serotonin receptor (HTR2A, HTR2C) genes were previously associated with antipsychotic-induced hyperprolactinaemia. Our aim was to evaluate whether aripiprazole affects prolactin secretion and its relationship with pharmacogenetics. Thirty-one healthy volunteers receiving a 10-mg single oral dose of aripiprazole were genotyped for 12 polymorphisms in CYP2D6, DRD2, DRD3, HTR2A and HTR2C genes by qPCR. Aripiprazole and dehydro-aripiprazole plasma concentrations were measured by HPLC-MS/MS. Prolactin concentrations of the 31 volunteers taking aripiprazole and 12 volunteers receiving ibuprofen were determined by ELISA. Prolactin concentrations after ibuprofen intake were considered as control, since it is known to cause no effect. Prolactin concentrations were slightly higher in the aripiprazole group compared to the ibuprofen group. All prolactin pharmacokinetic parameters were higher in females than in males. CYP2D6 poor and intermediate metabolizers had notably higher prolactin C_max and AUC_0-12 than normal and ultrarapid metabolizers. The DRD3 rs6280 polymorphism affected prolactin levels: volunteers carrying Ser/Ser genotype had significantly lower prolactin levels than volunteers carrying the Gly allele. Furthermore, HTR2C rs3813929 C/C homozygotes had significantly lower prolactin levels than T allele carriers. Nevertheless, aripiprazole did increase prolactin levels compared to ibuprofen.

Safety and efficacy of aripiprazole for the treatment of pediatric Tourette syndrome and other chronic tic disorders

Tourette syndrome is a childhood-onset chronic tic disorder characterized by multiple motor and vocal tics and often accompanied by specific behavioral symptoms ranging from obsessionality to impulsivity. A considerable proportion of patients report significant impairment in health-related quality of life caused by the severity of their tics and behavioral symptoms and require medical intervention. The most commonly used medications are antidopaminergic agents, which have been consistently shown to be effective for tic control, but are also associated with poor tolerability because of their adverse effects. The newer antipsychotic medication aripiprazole is characterized by a unique mechanism of action (D2 partial agonism), and over the last decade has increasingly been used for the treatment of tics. We conducted a systematic literature review to assess the available evidence on the efficacy and safety of aripiprazole in pediatric patients with Tourette syndrome and other chronic tic disorders (age range: 4–18 years). Our search identified two randomized controlled trials (involving 60 and 61 participants) and ten open-label studies (involving between six and 81 participants). The majority of these studies used two validated clinician-rated instruments (Yale Global Tic Severity Scale and Clinical Global Impression scale) as primary outcome measures. The combined results from randomized controlled trials and open-label studies showed that aripiprazole is an effective, safe, and well-tolerated medication for the treatment of tics. Aripiprazole-related adverse effects (nausea, sedation, and weight gain) were less frequent compared to other antidopaminergic medications used for tic management and, when present, were mostly transient and mild. The reviewed studies were conducted on small samples and had relatively short follow-up periods, thus highlighting a need for further trials to assess the long-term use of aripiprazole in pediatric patients with Tourette syndrome and other chronic tic disorders with measurement of its efficacy using both clinician-rated and self-report scales.

Metabolic syndrome and drug discontinuation in schizophrenia: a randomized trial comparing aripiprazole olanzapine and haloperidol

OBJECTIVE

To determine whether the prescription of aripiprazole, compared with olanzapine and haloperidol, was associated with a lower frequency of metabolic syndrome (MS) and treatment discontinuation at 1 year.

METHOD

Patients were randomly assigned to be treated open-label and according to usual clinical practice with either aripiprazole, olanzapine, or haloperidol and followed up for 1 year.

RESULTS

Three hundred out-patients with persistent schizophrenia were recruited in 35 mental health services. The intention-to-treat (ITT) analysis found no significant differences in the rate of MS between aripiprazole (37%), olanzapine (47%), and haloperidol (42%). Treatment discontinuation for any cause was higher for aripiprazole (52%) than for olanzapine (33%; OR, 0.41; P = 0.004), or haloperidol (37%; OR, 0.51; P = 0.030). No significant difference was found between olanzapine and haloperidol. Time to discontinuation for any cause was longer for olanzapine than for aripiprazole (HR, 0.55; P < 0.001). No significant differences were found between haloperidol and aripiprazole, or between olanzapine and haloperidol.

CONCLUSION

The prescription of aripiprazole did not significantly reduce the rates of MS, but its treatment retention was worse. Aripiprazole cannot be considered the safest and most effective drug for maintenance treatment of schizophrenia in routine care, although it may have a place in antipsychotic therapy.

The Effects of Antipsychotics on Prolactin Levels and Women's Menstruation

Introduction. Typical and atypical antipsychotic agent is currently used for treatment in the majority of patients with psychotic disorders. The aim of this review is to assess antipsychotic induced hyperprolactinaemia and the following menstrual dysfunction that affects fertility, quality of life, and therapeutic compliance of women. Method. For this purpose, Medline, PsychInfo, Cochrane library, and Scopus databases were accessed, with a focus on the publication dates between 1954 and 2012. Research of references was also performed and 78 studies were retrieved and used for the needs of this review. Results. A summary of several antipsychotics as well as frequency rates and data on hyperprolactinaemia and menstrual disorders for different agent is presented. Conclusion. Diverse prevalence rates of hyperprolactinaemia and menstrual abnormalities have been found about each medication among different studies. Menstruation plays an important role for women, thus, understanding, careful assessment, and management of hyperprolactinaemia could enhance their lives, especially when dealing with women that suffer from a psychotic disorder.

Strategies for Transitioning Therapy to Aripiprazole from Other Antipsychotics in Schizophrenia

OBJECTIVE:

To determine the optimal approach for transitioning therapy to aripiprazole from other antipsychotics in schizophrenia and to describe these strategies.

DATA SOURCES:

MEDLINE (January 2000-March 2012) and PubMed (January 2000-March 2012) searches were conducted using the search terms aripiprazole, switch, and switching. Citations from references were reviewed to identify additional primary literature.

STUDY SELECTION AND DATA EXTRACTION:

Articles identified as primary literature were considered for inclusion. Case series, opinion papers, and review articles were also examined. Literature was required to be in English. For evaluation purposes, included articles were randomized trials specifically comparing different switching strategies from an alternative antipsychotic to aripiprazole. Randomized trials and single-arm studies that evaluated the effect of a change to aripiprazole and reported switching methods were also reviewed but not evaluated.

DATA SYNTHESIS:

Aripiprazole, an atypical antipsychotic agent with a unique mechanism of action, causes fewer adverse effects when compared with other atypical antipsychotics. Patients unable to tolerate or unresponsive to their current regimens might benefit from a change to aripiprazole, but the best method for switching is unknown. Four randomized trials were identified that compared the efficacy, safety, and tolerability of at least 2 different switching strategies. The 5 strategies used a combination of immediate or titrated initiation of aripiprazole with immediate or tapered discontinuation of the current antipsychotic. A significant worsening of symptoms in the abrupt discontinuation group when compared with the combined tapered discontinuation groups was seen in 1 trial at week 2; however, all other comparisons yielded no significant differences among switching strategies.

CONCLUSIONS:

Strategies for transitioning therapy to aripiprazole from alternative antipsychotics in schizophrenia have been investigated in randomized trials, but studies have failed to establish a preferred method. Despite the lack of evidence, experts recommend an overlap strategy that includes maintaining the current antipsychotic dosage while titrating to a therapeutic dose of aripiprazole.

Descriptive analyses of the aripiprazole arm in the risperidone long-acting injectable versus quetiapine relapse prevention trial (ConstaTRE)

A recent randomized, open-label, relapse prevention trial (ConstaTRE) compared outcomes with risperidone long-acting injectable (RLAI) versus the oral atypical antipsychotic quetiapine. This study also included a small descriptive arm in which patients could also be randomized to aripiprazole. Results of this exploratory analysis are described here. Clinically stable adults with schizophrenia or schizoaffective disorder previously treated with oral risperidone, olanzapine, or an oral conventional antipsychotic were randomized to RLAI or aripiprazole. Efficacy and tolerability were monitored for up to 24 months. A total of 45 patients were treated with aripiprazole (10-30 mg/day) and 329 patients with RLAI (25-50 mg i.m. every 2 weeks). Relapse occurred in 27.3% (95% CI: 15.0-42.8%) of aripiprazole-treated and 16.5% (95% CI: 12.7-21.0%) of RLAI-treated patients. Kaplan-Meier estimates of mean (standard error) relapse-free period were 313.7 (20.4) days for aripiprazole and 607.1 (11.4) days for RLAI patients. Remission was achieved by 34.1% (95% CI: 20.5-49.9%) of aripiprazole and 51.1% (95% CI: 45.5-56.6%) of RLAI patients. Clinical global impression-change was improved ("minimally improved" to "very much improved") in 26.4% with RLAI and 15.9% with aripiprazole patients. Tolerability was generally good for both treatment groups. Weight gain (7.0% with RLAI vs. 4.4% with aripiprazole), extrapyramidal adverse events (AEs) (10.3% vs. 4.4%), and potentially prolactin-related AEs (4.6% vs. 0%) were more common with RLAI treatment, and gastrointestinal disorders were more common in aripiprazole-treated patients (22.2% vs. 6.1%). Time-to-relapse in stable patients with schizophrenia or schizoaffective disorder was numerically longer in RLAI-treated patients than in aripiprazole-treated patients although not statistically significant. Both treatments were generally well tolerated.

Hyperprolactinemia associated with psychotropics--a review

INTRODUCTION

Different classes of psychotropics can cause hyperprolactinemia to varying degrees. Among antipsychotics, typical agents and risperidone are the most frequent and significant offenders. In this review we discuss the pathophysiology, offending medications, assessment and management of hyperprolactinemia.

METHODS

We did a literature review between 1976 and 2008 using PubMed, MEDLINE, PsychINFO and Cochrane database. Search terms used were prolactin, hyperprolactinemia, psychotropics, antipsychotics, typical antipsychotics, atypical antipsychotics, antidepressants and SSRIs.

RESULTS

Prolactin elevation is more common with antipsychotics than with other classes of drugs. Typical antipsychotics are more prone to cause hyperprolactinemia than atypical agents. Management options include discontinuation of offending medication, switching to another psychotropic, supplementing concurrent hormonal deficiencies and adding a dopamine agonist or aripiprazole.

CONCLUSION

Clinicians need to be alert about the potential for hyperprolactinemia and its manifestations with these medications. Prolactin levels need to be monitored and other causes of hyperprolactinemia ruled out in suspected cases.

WS-50030 [7-{4-[3-(1H-inden-3-yl)propyl]piperazin-1-yl}-1,3-benzoxazol-2(3H)-one]: a novel dopamine D2 receptor partial agonist/serotonin reuptake inhibitor with preclinical antipsychotic-like and antidepressant-like activity

The preclinical characterization of WS-50030 [7-{4-[3-(1H-inden-3-yl)propyl]piperazin-1-yl}-1,3-benzoxazol-2(3H)-one] is described. In vitro binding and functional studies revealed highest affinity to the D(2) receptor (D(2L) K(i), 4.0 nM) and serotonin transporter (K(i), 7.1 nM), potent D(2) partial agonist activity (EC(50), 0.38 nM; E(max), 30%), and complete block of the serotonin transporter (IC(50), 56.4 nM). Consistent with this in vitro profile, WS-50030 (10 mg/kg/day, 21 days) significantly increased extracellular 5-HT in the rat medial prefrontal cortex, short-term WS-50030 treatment blocked apomorphine-induced climbing (ID(50), 0.51 mg/kg) in a dose range that produced minimal catalepsy in mice and induced low levels of contralateral rotation in rats with unilateral substantia nigra 6-hydroxydopamine lesions (10 mg/kg i.p.), a behavioral profile similar to that of the D(2) partial agonist aripiprazole. In a rat model predictive of antipsychotic-like activity, WS-50030 and aripiprazole reduced conditioned avoidance responding by 42 and 55% at 10 mg/kg, respectively. Despite aripiprazole's reported lack of effect on serotonin transporters, long-term treatment with aripiprazole or WS-50030 reversed olfactory bulbectomy-induced hyperactivity at doses that did not reduce activity in sham-operated rats, indicating antidepressant-like activity for both compounds. Despite possessing serotonin reuptake inhibitory activity in addition to D(2) receptor partial agonism, WS-50030 displays activity in preclinical models predictive of antipsychotic- and antidepressant efficacy similar to aripiprazole, suggesting potential efficacy of WS-50030 versus positive and negative symptoms of schizophrenia, comorbid mood symptoms, bipolar disorder, major depressive disorder, and treatment-resistant depression. Furthermore, WS-50030 provides a tool to further explore how combining these mechanisms might differentiate from other antipsychotics or antidepressants.

Immediate versus gradual suspension of previous treatments during switch to aripiprazole: results of a randomized, open label study

The aim of the present work was to investigate possible differences in terms of efficacy and tolerability between different switching options to aripiprazole. 77 subjects were randomly assigned to (1) administration of aripiprazole (10 mg) with simultaneous discontinuation of current antipsychotic; (2) administration of aripiprazole (10 mg) and tapering off current antipsychotic over 4 weeks with half dose after the first 2 weeks; (3) administration of aripiprazole (10 mg) and tapering off current antipsychotic over 6 weeks with half dose after the first 2 weeks. Efficacy assessments included CGI-S, CGI-I, BPRS and SANS. Safety assessments included SAS, BAS and AIMS. Severity of symptoms significantly decreased from baseline over the 12 weeks of treatment. Patients switched to aripiprazole with immediate discontinuation of the previous antipsychotic showed an increase of symptoms' severity at week 1. However, severity of side effects did not overall change significantly during the 12-weeks follow-up. Previous treatment's tapering off strategy for switching patients to aripiprazole could be preferable as compared to abrupt discontinuation, in order to prevent early worsening of symptoms and premature discontinuation of treatment, though this results has to be considered with caution given the limitations of the study.

Aripiprazole differentially affects mesolimbic and nigrostriatal dopaminergic transmission: implications for long-term drug efficacy and low extrapyramidal side-effects

Aripiprazole has been used effectively to treat schizophrenia in the clinic; however, its mechanisms of action are not clear. This study examined how short- and long-term aripiprazole treatment affects dopaminergic transmission in mesolimbic and nigrostriatal pathways. For comparison, the effects of haloperidol and olanzapine treatment were also examined. Aripiprazole significantly increased D2 receptor mRNA expression and decreased tyrosine hydroxylase (TH) mRNA expression in the ventral tegmental area (VTA) after 1- and 12-wk treatment, but had no effect in substantia nigra (SN) and nucleus accumbens (NAc). Aripiprazole also decreased dopamine transporter (DAT) binding density in NAc (for 1- and 12-wk treatment) and VTA (1-wk treatment). In contrast, haloperidol significantly increased D2 receptor binding density and decreased DAT binding density in NAc and caudate putamen (CPu) after 1- and 12-wk treatment, and it also decreases DAT binding in VTA after 12-wk treatment. Olanzapine had less widespread effects, namely an increase in D2 receptor mRNA in VTA after 12-wk treatment and decreased DAT binding in NAc after 1-wk treatment. These results suggest that aripiprazole has selective effects on the mesolimbic dopaminergic pathway. Selectively reducing dopamine synthesis in VTA is a possible therapeutic mechanism for the long-term efficacy of aripiprazole in controlling schizophrenia symptoms with reduced extrapyramidal side-effects.

A randomized, open-label comparison of 2 switching strategies to aripiprazole treatment in patients with schizophrenia: add-on, wait, and tapering of previous antipsychotics versus add-on and simultaneous tapering

Although recent treatment guidelines for schizophrenia recommend that the prior antipsychotic agent should remain stable for at least 2 weeks when aripiprazole is introduced, there is no trial-based evidence to support this strategy. This study was designed to compare this strategy with another conventional one in patients with schizophrenia. We conducted a randomized, 14-week, open-label trial to compare the following 2 switching strategies: (1) add-on of aripiprazole on a current regimen, wait for 4 weeks, and the tapering of prior antipsychotics and (2) add-on of aripiprazole and the simultaneous tapering of prior antipsychotics in patients with schizophrenia. Aripiprazole was initiated at 12 mg/d and then titrated between 12 and 30 mg. The previous antipsychotic medication was reduced biweekly by 25%. Assessments included the Clinical Global Impression Scale Schizophrenia version, the Drug-Induced Extrapyramidal Symptoms Scale, and the Subjective Well-being Under Neuroleptics, Short Version, Japanese Edition. Impressions toward their assigned strategy were also subjectively evaluated at baseline and end point. Fifty-three patients were enrolled, and 48 patients completed this trial. No significant differences were found in changes from the baseline in the total Clinical Global Impression Scale Schizophrenia version severity, Drug-Induced Extrapyramidal Symptoms Scale, and Subjective Well-being Under Neuroleptics, Short Version, Japanese Edition scores throughout the study period between the 2 strategies. Both strategies were judged by subjects to be tolerable and favorable without between-group differences. In conclusion, both strategies were found to be objectively safe and well tolerated. Taken together with similar results from subjective assessments, it would be reasonable to choose either of these 2 strategies in clinical practice based on a patients' preference.