piperidines and sertindole

The dose-response relationships of antipsychotic drugs for schizophrenia are not well defined, but such information would be important for decision making by clinicians. The authors sought to fill this gap by conducting dose-response meta-analyses.. A search of multiple electronic databases (through November 2018) was conducted for all placebo-controlled dose-finding studies for 20 second-generation antipsychotic drugs and haloperidol (oral and long-acting injectable, LAI) in people with acute schizophrenia symptoms. Dose-response curves were constructed with random-effects dose-response meta-analyses and a spline model. The outcome measure was total score reduction from baseline on the Positive and Negative Syndrome Scale or the Brief Psychiatric Rating Scale. The authors identified 95% effective doses, explored whether higher or lower doses than the currently licensed ones might be more appropriate, and derived dose equivalencies from the 95% effective doses.. Sixty-eight studies met the inclusion criteria. The 95% effective doses and the doses equivalent to 1 mg of oral risperidone, respectively, were as follows: amisulpride for patients with positive symptoms, 537 mg/day and 85.8 mg; aripiprazole, 11.5 mg/day and 1.8 mg; aripiprazole LAI (lauroxil), 463 mg every 4 weeks and 264 mg; asenapine, 15.0 mg/day and 2.4 mg; brexpiprazole, 3.36 mg/day and 0.54 mg; haloperidol, 6.3 mg/day and 1.01 mg; iloperidone, 20.13 mg/day and 3.2 mg; lurasidone, 147 mg/day and 23.5 mg; olanzapine, 15.2 mg/day and 2.4 mg; olanzapine LAI, 277 mg every 2 weeks and 3.2 mg; paliperidone, 13.4 mg/day and 2.1 mg; paliperidone LAI, 120 mg every 4 weeks and 1.53 mg; quetiapine, 482 mg/day and 77 mg; risperidone, 6.3 mg/day and 1 mg; risperidone LAI, 36.6 mg every 2 weeks and 0.42 mg; sertindole, 22.5 mg/day and 3.6 mg; and ziprasidone, 186 mg/day and 30 mg. For amisulpride and olanzapine, specific data for patients with predominant negative symptoms were available. The authors have made available on their web site a spreadsheet with this method and other updated methods that can be used to estimate dose equivalencies in practice.. In chronic schizophrenia patients with acute exacerbations, doses higher than the identified 95% effective doses may on average not provide more efficacy. For some drugs, higher than currently licensed doses might be tested in further trials, because their dose-response curves did not plateau.

Topics: Acute Disease; Administration, Oral; Antipsychotic Agents; Aripiprazole; Clozapine; Delayed-Action Preparations; Dose-Response Relationship, Drug; Haloperidol; Humans; Imidazoles; Indoles; Isoxazoles; Lurasidone Hydrochloride; Olanzapine; Paliperidone Palmitate; Piperazines; Piperidines; Quetiapine Fumarate; Quinolones; Risperidone; Schizophrenia; Schizophrenic Psychology; Thiazoles; Thiophenes

Serotonin-dopamine antagonists (SDAs) offer the possibility of improved treatment of schizophrenia compared with conventional neuroleptics and have superior safety profiles. Clinical trial data have so far been published for only three SDAs to date, namely, risperidone, sertindole, and olanzapine. Of these, extensive data are available only for risperidone, showing that at doses of 4 to 16 mg/day, it is superior to haloperidol at 10 to 20 mg/day. Furthermore, risperidone, 6 and 16 mg/day, significantly improved negative/symptoms, whereas 20 mg/day of haloperidol was ineffective. Risperidone also appears to cause fewer extrapyrimidal symptoms (EPS) than haloperidol, 10 or 20 mg/day. Similar advantages of risperidone over perphenazine have also been found. A clinical trial of sertindole showed that, at 20 mg/day, it was equivalent to haloperidol, 16 mg/day, and caused fewer EPS. Olanzapine, a chemical derivative of clozapine, has also been shown to be superior to haloperidol (10 to 20 mg/day) at doses of 7.5 to 17.5 mg/day. In addition, at doses of 12.5 to 17.5 mg/day, olanzapine was found to have a significantly superior effect on negative symptoms over haloperidol, 10 to 20 mg/day. Doses of up to 17.5 mg/day of olanzapine also caused fewer EPS than haloperidol, 10 to 20 mg/day. There was no evidence of any leukopenia in patients treated with olanzapine in this small study (N = 335). The low EPS liability of these SDAs, combined with their efficacy, suggests that SDAs should become the mainstay of treatment for schizophrenia.

Topics: Antipsychotic Agents; Benzodiazepines; Clinical Trials as Topic; Dopamine Antagonists; Humans; Imidazoles; Indoles; Isoxazoles; Olanzapine; Piperidines; Pirenzepine; Risperidone; Schizophrenia; Serotonin Antagonists

Cognitive deficits, including an impaired ability to shift perceptual attentional set, belong to the core features of schizophrenia, are associated with prefrontal cortical dysfunctions, and may involve glutamate NMDA receptors. Although phencyclidine disturbs cognitive flexibility, little is known about the effects of ketamine and other NMDA antagonists that differ in receptor subunit selectivity, particularly in the mouse species.. At different times following the administration of ketamine, the NMDA NR2B-subtype specific antagonist Ro 25-6981, or the atypical antipsychotic sertindole, male C57Bl/6J mice were investigated in a modified version of attentional set-shifting task (ASST).. Specific extra-dimensional shift (EDS) deficit was observed in all control mice. As revealed by the increased number of trials, time and errors to reach criterion, ketamine at 10 or 20 mg/kg given 50 min prior to sessions, but not at 10 mg/kg given 3 or 24 h prior to sessions, further worsened the EDS performance. Sertindole (2.5 mg/kg) prevented ketamine-induced cognitive inflexibility, although it did not affect ASST performance when given alone. In contrast to ketamine, Ro 25-6981 at 10 but not 3 mg/kg, reduced the number of trials and errors to criterion, suggesting a facilitation of cognitive flexibility. Finally, as revealed by the number of trials and time to criterion measures, Ro 25-6981 (10 mg/kg) administration to ketamine (10 mg/kg)-pretreated mice inhibited ketamine-induced cognitive inflexibility.. The present study provides an improved and reliable mouse ASST protocol and confirms and extends previous findings demonstrating that NR2B subunit-selective antagonists improve cognitive processes.

Topics: Animals; Attention; Cognition; Discrimination, Psychological; Dose-Response Relationship, Drug; Habituation, Psychophysiologic; Imidazoles; Indoles; Ketamine; Male; Mice; Mice, Inbred C57BL; Phenols; Piperidines; Receptors, N-Methyl-D-Aspartate; Reward; Schizophrenic Psychology; Set, Psychology

This study examined the efficacy of sertindole in comparison with a selective 5-HT(6) and a 5-HT(2A) receptor antagonist to reverse sub-chronic phencyclidine (PCP)-induced cognitive deficits in female rats.. In the first test, adult female hooded Lister rats were trained to perform an operant reversal learning task to 90% criterion. After training, rats were treated with PCP at 2 mg/kg (i.p.) or vehicle twice daily for 7 days, followed by 7 days washout. For the second test, novel object recognition (NOR), a separate batch of rats, had the same sub-chronic PCP dosing regime and washout period. In reversal learning, rats were treated acutely with sertindole, the selective 5-HT(2A) receptor antagonist M100.907 or the selective 5-HT(6) receptor antagonist SB-742457.. The PCP-induced selective reversal learning deficit was significantly improved by sertindole, M100.907 and SB-742457. Sertindole also significantly improved the sub-chronic PCP-induced deficit in NOR, a test of episodic memory following a 1 min and 1 h inter-trial interval. In vivo binding studies showed that the dose-response relationship for sertindole in this study most closely correlates with affinity for 5-HT(6) receptor in vivo binding in striatum, although contribution from binding to 5-HT(2A) receptors in vivo in cortex may also provide an important mechanism.. The efficacies of selective 5-HT(2A) and 5-HT(6) receptor antagonists suggest potential mechanisms mediating the effects of sertindole, which has high affinity for these 5-HT receptor subtypes. The sertindole-induced improvement in cognitive function in this animal model suggests relevance for the management of cognitive deficit symptoms in schizophrenia.

Topics: Animals; Antipsychotic Agents; Cognition Disorders; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Fluorobenzenes; Imidazoles; Indoles; Memory Disorders; Phencyclidine; Piperidines; Quinolines; Rats; Receptor, Serotonin, 5-HT2A; Receptors, Serotonin; Reversal Learning; Schizophrenia; Sulfones

Therapies treating cognitive impairments in schizophrenia especially deficits in executive functioning are not available at present.. The current study evaluated the effect of ampakine CX516 in reversing deficits in executive functioning as represented in two animal models of schizophrenia and assessed by a rodent analog of the intradimensional-extradimensional (ID-ED) attentional set-shifting task. The second generation antipsychotic, sertindole, provided further validation of the schizophrenia-like disease models.. Animals were subjected to (a) sub-chronic or (b) early postnatal phencyclidine (PCP) treatment regimes: (a) Administration of either saline or PCP (5 mg/kg, intraperitonally b.i.d. for 7 days) followed by a 7-day washout period and testing on day 8. (b) On postnatal days (PNDs) 7, 9, and 11, rats were subjected to administration of either saline or PCP (20 mg/kg, subcutaneously (s.c.)) and tested on PNDs 56-95, after reaching adulthood. The single test session required rats to dig for food rewards in a series of discriminations following acute administration of either vehicle, or CX516 (5-40 mg/kg, s.c.), or sertindole (1.25 mg/kg, perorally).. The specific extradimensional deficits produced by sub-chronic or early postnatal PCP treatment were significantly attenuated by sertindole and dose-dependently by CX516.. Findings here further establish PCP treatment as model of executive functioning deficits related to schizophrenia and provide evidence that direct glutamatergic interventions could improve these, when assessed in the ID-ED attentional set-shifting task.

Topics: Animals; Antipsychotic Agents; Attention; Dioxoles; Disease Models, Animal; Dose-Response Relationship, Drug; Imidazoles; Indoles; Male; Phencyclidine; Piperidines; Rats; Schizophrenia

Second-generation antipsychotics have some beneficial effect on cognition. Recent studies, furthermore, indicate differential effects of second-generation antipsychotics on impairment in executive cognitive function.. We evaluated the effect of the second-generation antipsychotic drug, sertindole, on extracellular levels of dopamine (DA), acetylcholine (ACh), and glutamate (Glu) in the rat medial prefrontal cortex (mPFC). Risperidone was studied for comparison. Moreover, selective serotonin 5-HT(2A), 5-HT(2C), and 5-HT(6) receptor antagonists were used, given alone and in combination with the preferential DA D(2) receptor antagonist, haloperidol, to further clarify the action of the two drugs.. Rats were treated acutely with vehicle or drugs, and extracellular levels of neurotransmitters were assessed by microdialysis in freely moving animals.. Sertindole and risperidone significantly increased extracellular levels of DA. Haloperidol; the 5-HT(2A) receptor antagonist, M100907; the 5-HT(2C) receptor antagonist, SB242084; and the 5-HT(6) receptor antagonist, GSK-742457, induced minor increases in levels of DA, but the three latter compounds raised the DA levels notably in combination with haloperidol. Sertindole and risperidone significantly increased the extracellular levels of ACh but only sertindole raised the extracellular levels of Glu. The selective 5-HT(6) receptor antagonist, SB-271046, significantly increased the extracellular levels of Glu.. Sertindole and risperidone markedly increased extracellular levels of DA in mPFC. The built-in 5-HT(2A)/5-HT(2C)/D(2) receptor antagonism of the two drugs might be involved in this action. Both drugs increased the extracellular levels of ACh but only sertindole enhanced Glu levels. The high affinity of sertindole for the 5-HT(6) receptor compared to risperidone may differentiate sertindole from risperidone.

Topics: Acetylcholine; Animals; Antipsychotic Agents; Dopamine; Dopamine D2 Receptor Antagonists; Drug Synergism; Extracellular Space; Fluorobenzenes; Glutamic Acid; Haloperidol; Imidazoles; Indoles; Male; Microdialysis; Piperidines; Prefrontal Cortex; Rats; Rats, Sprague-Dawley; Risperidone; Serotonin 5-HT2 Receptor Antagonists

The effects of acute intravenous administration of several new, atypical antipsychotic drugs (APDs): olanzapine (0.05 and 1.0 mg/kg), sertindole (0.1 and 1.0 mg/kg) and quetiapine (0.25 and 2.5 mg/kg), a selective 5-HT(2A) receptor antagonist, M100907 (0.03 and 0.3 mg/kg), and an alpha(1)-adrenoceptor antagonist, prazosin (0.3 mg/kg), on regional dopamine output were examined in the two subdivisions of the nucleus accumbens (NAC), the core and shell, which seem associated with motor control and limbic functions, respectively, by using in vivo differential normal pulse voltammetry in anaesthetised, pargyline-pretreated rats. Both quetiapine and sertindole, in the two doses used, caused a more pronounced dopamine release in the shell than in the core region of the NAC. In contrast, the low dose of olanzapine increased dopamine output almost to the same extent in both regions, whereas the high dose increased dopamine output to a greater extent in the core. M100907 selectively increased dopamine output in the shell. Also, prazosin significantly increased dopamine output in the shell, but not in the core. The results indicate that both 5-HT(2A) and alpha(1)-adrenoceptor antagonism may play an important role in the preferential effect of atypical APDs on dopamine output in the shell versus the core of the NAC.

Topics: Adrenergic Antagonists; Animals; Antipsychotic Agents; Benzodiazepines; Dibenzothiazepines; Dopamine; Fluorobenzenes; Imidazoles; Indoles; Male; Nucleus Accumbens; Olanzapine; Piperidines; Pirenzepine; Quetiapine Fumarate; Rats; Rats, Sprague-Dawley; Receptor, Serotonin, 5-HT2A; Receptors, Adrenergic, alpha-1; Receptors, Serotonin; Serotonin Antagonists