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Query: UMLS:C0036341 (
schizophrenia
)
60,220
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Ziprasidone
(CP-88,059) is a combined 5-HT (serotonin) and dopamine receptor antagonist which exhibits potent effects in preclinical assays predictive of antipsychotic activity. Whereas the compound is a dopamine antagonist in vitro and in vivo, its most potent action is antagonism of 5-HT2A receptors, where its affinity is an order of magnitude greater than that observed for dopamine D2 sites. Laboratory and clinical findings have led to a hypothesis that antagonism of 5-HT2A receptors in the brain limits the undesirable motor side effects associated with dopamine receptor blockade and improves efficacy against the negative symptoms of
schizophrenia
.
Ziprasidone
possesses an in vitro 5-HT2A/dopamine D2 receptor affinity ratio higher than any clinically available antipsychotic agent. In vivo, ziprasidone antagonizes 5-HT2A receptor-induced head twitch with 6-fold higher potency than for blockade of d-amphetamine-induced hyperactivity, a measure of central dopamine D2 receptor antagonism.
Ziprasidone
also has high affinity for the 5-HT1A, 5-HT1D and 5-HT2C receptor subtypes, which may further enhance its therapeutic potential. The prediction of antipsychotic efficacy without severe motor side effects is supported by the relatively weak potency of ziprasidone to produce catalepsy in animals, contrasted with its potent antagonism of conditioned avoidance responding and dopamine agonist-induced locomotor activation and stereotypy. The compound is well tolerated in animals at doses producing effective dopamine antagonism in the brain.
Ziprasidone
should be a valuable addition to the treatment of psychotic disorders.
...
PMID:Ziprasidone (CP-88,059): a new antipsychotic with combined dopamine and serotonin receptor antagonist activity. 756 37
Risperidone and its active metabolite 9-OH-risperidone were compared to reference antipsychotic drugs (haloperidol, pipamperone, fluspirilene, clozapine, zotepine) and compounds under development (olanzapine, seroquel, sertindole, ORG-5222, ziprasidone) for in vitro binding to neurotransmitter receptors in brain tissue and on membranes of recombinant cells expressing cloned human receptors and for in vivo occupancy of neurotransmitter receptors in rat and guinea-pig brain following acute treatment (2 h., s.c.). An ex vivo autoradiography technique was applied to determine the receptor occupancy by the drugs administered in vivo. Of particular interest are the central 5HT2A receptors and D2-type receptors. Predominant 5HT2A receptor antagonism is supposed to add to an atypical profile of the antipsychotics (treatment of the negative symptoms, low incidence of extrapyramidal side effects). D2 antagonism is required the treatment of positive symptoms. A contribution of the new dopamine receptor subtypes D3 and in particular D4 receptors has been proposed. In vitro, all compounds, except the 'typical' antipsychotics haloperidol and fluspirilene, showed higher affinity for 5HT2A than for D2 receptors. Subnanomolar affinity for human 5HT2A receptors was observed for ORG-5222, sertindole, risperidone, 9-OH-risperidone and ziprasidone. Fluspirilene, ORG-5222, haloperidol, ziprasidone, risperidone, 9-OH-risperidone and zotepine displayed nanomolar affinity for human D2 receptors. Sertindole and olanzapine were slightly less potent. Pipamperone, clozapine and seroquel showed 2 orders of magnitude lower D2 affinity in vitro. Clozapine, but even more so pipamperone, displayed higher affinity for D4 than for D2 receptors. For most other compounds, D4 affinity was only slightly lower than their D2 affinity. Seroquel was totally devoid of D4 affinity. None of the compounds had nanomolar affinity for D1 receptors; their affinity for D3 receptors was usually slightly lower than for D2 receptors. In vivo, ORG-5222, risperidone, pipamperone, 9-OH-risperidone, sertindole, olanzapine, zotepine and clozapine maintained a higher potency for occupying 5HT2A than D2 receptors. Risperidone and ORG-5222 had 5HT2A versus D2 potency ratio of about 20. Highest potency for 5HT2A receptor occupancy was observed for ORG-5222 followed by risperidone and olanzapine.
Ziprasidone
exclusively occupied 5HT2A receptors. ORG-5222, haloperidol, fluspirilene and olanzapine showed the highest potency for occupying D2 receptors. No regional selectivity for D2 receptor occupancy in mesolimbic versus nigrostriatal areas was detected for any of the test compounds. Risperidone was conspicuous because of its more gradual occupancy of D2 receptors; none of the other compounds showed this property. The various compounds also displayed high to moderate occupancy of adrenergic alpha 1 receptors, except fluspirilene and ziprasidone. Clozapine, zotepine, ORG-5222 and sertindole occupied even more alpha 1 than D2 receptors. Clozapine showed predominant occupancy of H1 receptors and occupied cholinergic receptors with equivalent potency to D2 receptors. A stronger predominance of 5HT2A versus D2 receptor occupancy combined with a more gradual occupancy of D2 receptors differentiates risperidone and its 9-OH-metabolite from the other antipsychotic compounds in this study. The predominant 5HT2A receptor occupancy probably plays a role in the beneficial action of risperidone on the negative symptoms of
schizophrenia
, whereas maintenance of a moderate occupancy of D2 receptors seems adequate for treating the positive symptoms of
schizophrenia
. A combined 5HT2A and D2 occupancy and the avoidance of D2 receptor overblockade are believed to reduce the risk for extrapyra
...
PMID:Risperidone compared with new and reference antipsychotic drugs: in vitro and in vivo receptor binding. 893 1
Ninety patients with
schizophrenia
or schizoaffective disorder according to DSM-III-R criteria participated in this double-blind, exploratory, dose-ranging trial. After a single-blind washout period of 4 to 7 days, patients were randomly assigned to receive one of four fixed doses of the new antipsychotic, ziprasidone 4 (N = 19), 10 (N = 17), 40 (N = 17), or 160 (N = 20) mg/day or haloperidol 15 mg/day (N = 17) for 4 weeks. A dose-response relationship among ziprasidone groups was established for improvements in Clinical Global Impression Severity (CGI-S) score (p = 0.002) but not in Brief Psychiatric Rating Scale (BPRS) total score (p = 0.08). The intent-to-treat analysis of mean changes from baseline in the BPRS total, BPRS Psychosis core, and CGI-S scores demonstrated that ziprasidone 160 mg/day was comparable with haloperidol in reducing overall psychopathology and positive symptoms and was superior to ziprasidone 4 mg/day. Despite the small sample size and short duration of the trial, the improvement in CGI-S with both ziprasidone 160 mg/day and haloperidol 15 mg/day was statistically significantly greater than with ziprasidone 4 mg/day (p = 0.001 andp = 0.005, respectively). The percentage of patients classified as responders on both the BPRS total (> or = 30% improvement) and CGI-Improvement (score of 1 or 2) scales in the ziprasidone 160 mg/day group was similar to that in the haloperidol group and nonsignificantly greater than that in the ziprasidone 4 mg/day group. On all assessments of clinical efficacy, the improvements associated with ziprasidone 4 mg/day, 10 mg/day, and 40 mg/day were similar. Concomitant benztropine use at any time during the study was less frequent with ziprasidone 160 mg/day (15%) than with haloperidol (53%). Haloperidol was associated with a sustained hyperprolactinemia, unlike ziprasidone, where only transient elevations in prolactin that returned to normal within the dosing interval were observed.
Ziprasidone
was well tolerated, and the incidence of adverse events was similar in all groups. The results of this study suggest that ziprasidone 160 mg/day is as effective as haloperidol 15 mg/day in reducing overall psychopathology and positive symptoms of an acute exacerbation of
schizophrenia
or schizoaffective disorder but has a lower potential to induce extrapyramidal symptoms.
...
PMID:An exploratory haloperidol-controlled dose-finding study of ziprasidone in hospitalized patients with schizophrenia or schizoaffective disorder. 969 Jun 95
A double-blind, placebo-controlled, multicenter study, was performed to evaluate the efficacy and safety of ziprasidone in 139 patients with an acute exacerbation of
schizophrenia
or schizoaffective disorder. Patients were randomized to receive ziprasidone 40 mg/day, 120 mg/day or placebo for 28 days.
Ziprasidone
120 mg/day was significantly more effective than placebo in improving the BPRS total, CGI-S. BPRS depression cluster and BPRS anergia cluster scores (all P < 0.05). Similarly, the percentages of patients classified as responders on the BPRS (> or = 30% reduction) and the CGI improvement (score < or = 2) were significantly greater with ziprasidone 120 mg/day compared with placebo (P < 0.05). The number of patients who experienced an adverse event was similar in all three treatment groups, and discontinuation due to adverse events was rare (five of 91 ziprasidone-treated patients). The most frequently reported adverse events, that were more common in either ziprasidone group than in the placebo group, were dyspepsia, constipation, nausea and abdominal pain. There was a notably low incidence extrapyramidal side-effects (including akathisia) and postural hypotension and no pattern of laboratory abnormalities or apparent weight gain.
Ziprasidone
-treated patients were not clinically different from placebo-treated patients on the Simpson-Angus Rating scale, Barnes Akathisia scale and AIMS assessments. These results indicate that ziprasidone 120 mg/day is effective in the treatment of the positive, negative and affective symptoms of
schizophrenia
and schizoaffective disorder with a very low side-effect burden.
...
PMID:Ziprasidone 40 and 120 mg/day in the acute exacerbation of schizophrenia and schizoaffective disorder: a 4-week placebo-controlled trial. 986 Jan 8
Ziprasidone
is an antipsychotic agent indicated primarily for the treatment of
schizophrenia
. An intramuscular dosage form of ziprasidone was developed using beta-cyclodextrin sulfobutyl ether (SBECD) to solubilize the drug by complexation. Inclusion complexation of ziprasidone mesylate (ZM) with SBECD was studied by circular dichroism (CD) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, Monte Carlo simulations, phase-solubility studies, and counterion titration. The results of the studies indicate that ZM, of which the counterion is not fully dissociated from the drug, forms a 1:1 inclusion complex with SBECD with the benzisothiazole group positioned in the cavity. A mathematical model was developed to calculate stability constants of inclusion complexes for the ion pair (Z+M-:SBECD) and the dissociated ionic form (Z+:SBECD) of ZM; the values were 7892 and 957 M(-1), respectively. The model also allowed the dissociation constants of noncomplexed and complexed ZM to be calculated; the value of the former is 8-fold greater than the value of the latter. These results indicate that the inclusion complex formation of the ion pair is favored over that of the dissociated ionic form of ZM, and that the dissociation of ZM is suppressed by inclusion complexation with SBECD.
...
PMID:Inclusion complexation of ziprasidone mesylate with beta-cyclodextrin sulfobutyl ether. 1018 67
In this double-blind study, patients with an acute exacerbation of
schizophrenia
or schizoaffective disorder were randomized to receive either ziprasidone 80 mg/day (n = 106) or 160 mg/day (n = 104) or placebo (n = 92), for 6 weeks. Both doses of ziprasidone were statistically significantly more effective than placebo in improving the PANSS total, BPRS total, BPRS core items, CGI-S, and PANSS negative subscale scores (p < .05).
Ziprasidone
160 mg/day significantly improved depressive symptoms in patients with clinically significant depression at baseline (MADRS > or = 14, over-all mean 23.5) (p < .05) as compared with placebo. The percentage of patients experiencing adverse events was similar in each treatment group, and resultant discontinuation was rare. The most frequent adverse events associated with ziprasidone were generally mild dyspepsia, nausea, dizziness, and transient somnolence.
Ziprasidone
was shown to have a very low liability for inducing movement disorders and weight gain. The results indicate that ziprasidone is effective and well tolerated in the treatment of the positive, negative, and depressive symptoms of an acute exacerbation of
schizophrenia
or schizoaffective disorder.
...
PMID:Ziprasidone 80 mg/day and 160 mg/day in the acute exacerbation of schizophrenia and schizoaffective disorder: a 6-week placebo-controlled trial. Ziprasidone Study Group. 1019 29
The recent introduction of several antipsychotic medications has raised expectations for better pharmacological management of
schizophrenia
. Although conventional and new neuroleptics (Risperidone, Olanzapine, Seroquel and soon to be released
Ziprasidone
) are generally comparable in terms of efficacy; the new antipsychotic medications possess a better side-effects profile and are overall, much better tolerated. The reintroduction of Clozapine as an effective antipsychotic for treatment refractoriness has also improved management for a segment of the schizophrenic population who failed to respond adequately to other antipsychotic medications. Such increased benefits from new antipsychotic medications come with a higher acquisition cost that has somewhat strained the historically low psychiatric budgets. The question then was whether the expected benefits of the new antipsychotics can offset the high cost of these medications in the long-term. In that context, quality of life assessment has provided a tool for the comparative analysis of new and conventional antipsychotic medications, particularly regarding their impact on functional status and satisfaction. In a recently concluded study, we demonstrated that the new antipsychotic medications are subjectively much better tolerated and have a more favourable impact on quality of life compared with conventional neuroleptics. The ultimate question is whether such favourable benefits can translate in the future into better compliance with medications and improved long-term outcomes.
...
PMID:Quality of life and new antipsychotics in schizophrenia. Are patients better off? 1068 10
Ziprasidone
(5-[2-(4-(1,2,-benzisothiazol-3-yl) piperazin-l-yl] ethyl]-6 -chloro indolin-2-one hydrochloride hydrate) is a novel antipsychotic with a pattern of receptor occupancy and preclinical attributes predictive of broad therapeutic efficacy and a favourable tolerability profile in the treatment of psychotic illness. Clinical trials indicate that ziprasidone is effective against positive, negative and affective symptoms in
schizophrenia
and schizoaffective disorder with minimal motor, cognitive, weight gain, prolactin related, or anticholinergic side effects. In addition, an im. formulation appears to be rapidly effective with significantly less motor side effect liability than haloperidol.
...
PMID:Ziprasidone: comprehensive overview and clinical use of a novel antipsychotic. 1106 Jul 12
The atypical antipsychotics have been shown to have superior efficacy compared with typical antipsychotics such as haloperidol, particularly in the treatment of negative symptoms of
schizophrenia
. Furthermore, they induce less extrapyramidal effects. However, following clinical use, marked bodyweight gain has been frequently observed with some of the atypical antipsychotic drugs. In order to examine and compare the frequency, amount and conditions of bodyweight gain during treatment with atypical antipsychotics, studies concerning bodyweight gain with these agents were identified through a MEDLINE search from 1966 to March 2000. Although comparison is limited by the different designs and recruitment procedures of the reviewed studies, the available data support the notion that the frequency as well as the amount of bodyweight gain is high in patients treated with olanzapine (average bodyweight gain 2.3 kg/month), clozapine (1.7 kg/month), quetiapine (1.8 kg/month), and possibly also zotepine (2.3 kg/month). Moderate changes in bodyweight have been observed in the treatment with risperidone (average bodyweight gain 1.0 kg/month).
Ziprasidone
seems to induce only slight bodyweight changes (0.8 kg/month). Bodyweight gain most frequently occurs in the first 12 weeks of treatment. Patients who were underweight at the beginning of treatment are at highest risk of gaining bodyweight. The underlying pathomechanism still remains largely unclear. The relative receptor affinities of the atypical antipsychotics for histamine H1 receptors as well as the ratio of their affinity for serotonin 5-HT2 and dopamine D2 receptors appear to be the most robust correlate of bodyweight gain. Furthermore, the induction of leptin secretion may have an important impact on bodyweight gain in patients treated with atypical antipsychotics. Although many questions concerning the pathogenesis of bodyweight gain remain unresolved, this adverse effect has to be taken into consideration when prescribing the atypical antipsychotics, particularly in view its affect on compliance during long term treatment and the long term effects of obesity on mortality and morbidity.
...
PMID:Bodyweight gain with atypical antipsychotics. A comparative review. 1173 56
Although the introduction of antipsychotic drugs in 1954 was a breakthrough in the treatment of patients with
schizophrenia
, these agents have a number of adverse effects that limit effectiveness and compliance. The atypical antipsychotic drugs provide an improved tolerability profile, particularly in minimizing extrapyramidal side effects; however, they are associated with significant weight gain, which may be related to growing evidence linking the atypical agents with diabetes and hyperlipidemia.
Ziprasidone
, a new atypical antipsychotic drug, was demonstrated in clinical trials to be more efficacious than placebo and similar in efficacy to haloperidol in the treatment of
schizophrenia
. Like the existing atypical agents, ziprasidone has a rate of extrapyramidal side effects similar to that of placebo and does not cause significant elevations in prolactin levels. In contrast, ziprasidone has a low propensity for causing weight gain. For patients requiring an antipsychotic drug, ziprasidone represents a new treatment option with a limited adverse effect profile.
...
PMID:Ziprasidone, a new atypical antipsychotic drug. 1140 Nov 84
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