Pharmacokinetics and bioavailability of benperidol in schizophrenic patients after intravenous and two different kinds of oral application

The Influence of Selected Antipsychotic Drugs on Biochemical Aspects of Alzheimer's Disease

The aim of this study was to assess the potency of selected antipsychotic drugs (haloperidol (HAL), bromperidol (BRMP), benperidol (BNP), penfluridol (PNF), pimozide (PIM), quetiapine (QUET) and promazine (PROM)) on the main pathological hallmarks of Alzheimer's disease (AD). Binary mixtures of donepezil and antipsychotics produce an anti-BuChE effect, which was greater than either compound alone. The combination of rivastigmine and antipsychotic drugs (apart from PNF) enhanced AChE inhibition. The tested antipsychotics (excluding HAL and PNF) significantly reduce the early stage of Aβ aggregation. BRMP, PIM, QUET and PROM were found to substantially inhibit Aβ aggregation after a longer incubation time. A test of human erythrocytes hemolysis showed that short-term incubation of red blood cells (RBCs) with QUET resulted in decreased hemolysis. The antioxidative properties of antipsychotics were also proved in human umbilical vein endothelial cells (HUVEC); all tested drugs were found to significantly increase cell viability. In the case of astrocytes, BNP, PNF, PIM and PROM showed antioxidant potential.

Metabolism of 4-Aminopiperidine Drugs by Cytochrome P450s: Molecular and Quantum Mechanical Insights into Drug Design

4-Aminopiperidines are a variety of therapeutic agents that are extensively metabolized by cytochrome P450s with CYP3A4 as a major isoform catalyzing their N-dealkylation reaction. However, its catalytic mechanism has not been fully elucidated in a molecular interaction level. Here, we applied theoretical approaches including the molecular mechanics-based docking to study the binding patterns and quantum mechanics-based reactivity calculations. They were supported by the experimental human liver microsomal clearance and P450 isoform phenotyping data. Our results herein suggested that the molecular interactions between substrates and CYP3A4 active site residues are essential for the N-dealkylation of 4-aminopiperidines. We also found that the serine 119 residue of CYP3A4 may serve as a key hydrogen-bonding partner to interact with the 4-amino groups of the studied drugs. The reactivity of the side chain α-carbon hydrogens drives the direction of catalysis as well. As a result, structure-based drug design approaches look promising to guide drug discovery programs into the optimized drug metabolism space.

Benperidol for schizophrenia

BACKGROUND

Benperidol is a relatively old antipsychotic drug that has been marketed since 1966. It has been used in Germany for 30 years, but is also available in Belgium, Greece, Italy, the Netherlands and the UK. Benperidol is a butyrophenone antipsychotic, with the highest neuroleptic potency in terms of D2 receptor blockade. Those taking it are therefore reputed to be at high risk of extrapyramidal side effects, but benperidol's unusual profile may render it valuable to subgroups of people with schizophrenia.

OBJECTIVES

To examine the clinical effects and safety of benperidol for those with schizophrenia and schizophrenia-like psychoses.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group's register (November 2004) for this update.

SELECTION CRITERIA

We included all randomised controlled trials that compared benperidol with other treatments for people with schizophrenia, or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We reliably selected studies, quality rated them and extracted data. We independently extracted data but excluded data if loss to follow up was greater than 50%. For dichotomous data, we estimated relative risks (RR), with the 95% confidence intervals (CI). Where possible, we calculated the number needed to treat/harm statistic (NNT/H) and used intention-to-treat analysis.

MAIN RESULTS

The update yielded no further studies for inclusion in the review. We identified only one unpublished poorly randomised controlled trial (N=40, duration 30 days, comparison perphenazine). Although benperidol was inferior to perphenazine (1 RCT, N=40, global state no better or worse RR 8.0 CI 2.1 to 30, NNH 1.4 CI 1 to 2) poor reporting suggests that an overestimate of effect is likely. It was not possible to report other outcomes.

AUTHORS' CONCLUSIONS

Currently, there are insufficient data from randomised trials to assess the clinical effects of benperidol. This compound merits further research interest.