Psychotropic drugs and liver disease: A critical review of pharmacokinetics and liver toxicity

The Effect of Liver and Kidney Disease on the Pharmacokinetics of Clozapine and Sildenafil: A Physiologically Based Pharmacokinetic Modeling

Background and Objectives

Physiologically based pharmacokinetic (PBPK) modeling permits clinical scientists to reduce practical constraints for clinical trials on patients with special diseases. In this study, simulations were carried out to validate the pharmacokinetic parameters of clozapine and sildenafil using Simcyp^® simulator in young male adults and compare the effect of renal or hepatic impairment on the pharmacokinetic parameters of clozapine and sildenafil. Also, the effect of age on pharmacokinetic parameters of both drugs was investigated in healthy population and in patients with renal and hepatic impairment.

Methods

A full PBPK model was built in the simulator for clozapine and sildenafil based on physicochemical properties and observed clinical results. The model used was Advanced, Dissolution, Absorption and Metabolism (ADAM) for both drugs.

Results

The PBPK model adequately predicted the pharmacokinetic parameters of clozapine and sildenafil for the healthy adult population. In the simulation results, the bioavailability of both drugs was remarkably raised in both renal and hepatic impairment in young and elderly populations.

Conclusion

PBPK modeling could be helpful in the investigation and comparison of the pharmacokinetics in populations with specific disease conditions.

Organ-Specific Screening for Protein Damage Using Magnetic Bead Bioreactors and LC-MS/MS

A new 96-well plate methodology for fast, enzyme-multiplexed screening for metabolite-protein adducts was developed. Magnetic beads coated with metabolic enzymes were used to make potentially reactive metabolites that can react with test protein in the wells, followed by sample workup in multiple 96-well filter plates for LC-MS/MS analysis. Incorporation of human microsomes from multiple organs and selected supersomes of single cytochrome P450 (cyt P450) enzymes on the magnetic beads provided a broad spectrum of metabolic enzymes. The reacted protein was then isolated, denatured, reduced, alkylated, and digested, and peptides were collected in a sequence of 96-well filter plates for analysis. Method performance was evaluated by trapping acetaminophen reactive metabolite N-acetyl-p-benzoquinoneimine (NAPQI) with human glutathione S-transferase pi (hGSTP), human serum albumin (HSA), and bovine serum albumin (BSA) as model target proteins. Relative amounts of acetaminophen metabolite and hGSTP adducts were compared with 10 different cyt P450 enzymes. Human liver microsomes and CYP1A2 supersomes showed the highest bioactivation rate for adduct formation, in which all four cysteines of hGSTP reacted with NAPQI. Eight cysteines of HSA and four cysteines of BSA have been detected to react with NAPQI. This method has the potential for fast multienzyme protein adduct screening with high efficiency and accuracy.

Treatment of Delirium in Older Persons: What We Should Not Do!

The presentation of common acute diseases in older age is often referred to as “atypical”. Frequently, the symptoms are neither single nor tissue related. In most cases, the onset of symptoms and diseases is the expression of a diminished reserve with a failure of the body system and imbalance of brain function. Delirium is one of the main devastating and prevalent atypical symptoms and could be considered as a geriatric syndrome. It encompasses an array of neuropsychiatric symptoms and represents a disarrangement of the cerebral function in response to one or more stressors. The most recent definition, reported in the DSM-V, depicts delirium as a clear disturbance in attention and awareness. The deficit is to be developed in a relatively short time period (usually hours or days). The attention disorder must be associated with another cognitive impairment in memory, orientation, language, visual-spatial or perception abilities. For the treatment, it is imperative to remove the potential causes of delirium before prescribing drugs. Even a non-pharmacological approach to reducing the precipitating causes should be identified and planned. When we are forced to approach the pharmacological treatment of hyperactive delirium in older persons, we should select highly cost-effective drugs. High attention should be devoted to the correct balance between improvement of psychiatric symptoms and occurrence of side effects. Clinicians should be guided in the correct choice of drugs following cluster symptoms presentation, excluding drugs that could potentially produce complications rather than advantages. In this brief point-of-view, we propose a novel pharmacological flow-chart of treatment in relation to the basic clusters of diseases of an older patient acutely admitted to the hospital and, in particular, we emphasize “What We Should Not Do!”, with the intention of avoiding possible side effects of drugs used.

Understanding variability in the pharmacokinetics of atypical antipsychotics - focus on clozapine, olanzapine and aripiprazole population models

Antipsychotic medicines are widely used for the management of psychotic symptoms regardless of the underlying diagnosis. Most atypical antipsychotics undergo extensive metabolism prior to excretion. Various factors may influence their pharmacokinetics, particularly elimination, leading to highly variable drug concentrations between individual patients following the same dosing regimen. Population pharmacokinetic approach, based on nonlinear mixed effects modeling, is a useful tool to identify covariates explaining pharmacokinetic variability, as well as to characterize and distinguish unexplained residual and between-subject (interindividual) variability. In addition, this approach allows the use of both sparsely and intensively sampled data. In this paper, we reviewed the pharmacokinetic characteristics of clozapine, olanzapine and aripiprazole, focusing on a population modeling approach. In particular, models based on a nonlinear mixed effects approach performed by NONMEM^® software in order to identify and quantify sources of pharmacokinetic variability are presented. Population models were identified through systematic searches of PubMed and sixteen studies were selected. Some of the factors identified that significantly contribute to variability in elimination among clozapine, olanzapine, and aripiprazole are demographic characteristics, body weight, genetic polymorphism, smoking and in some cases drug interactions. Scientific research based on pharmacometric modeling is useful to further characterize sources of variability and their combined effect.

Transport of Bupropion and its Metabolites by the Model CHO and HEK293 Cell Lines

BACKGROUND

Bupropion (BUP) is widely used as an antidepressant and smoking cessation aid. There are three major pharmacologically active metabolites of BUP, Erythrohydrobupropion (EB), Hydroxybupropion (OHB) and Threohydrobupropion (TB). At present, the mechanisms underlying the overall disposition and systemic clearance of BUP and its metabolites have not been well understood, and the role of transporters has not been studied.

OBJECTIVE

The goal of this study was to investigate whether BUP and its active metabolites are substrates of the major hepatic uptake and efflux transporters.

METHOD

CHO or HEK293 cell lines or plasma membrane vesicles that overexpress OATP1B1, OATP1B3, OATP2B1, OATP4A1, OCT1, BCRP, MRP2 or P-gp were used in cellular or vesicle uptake and inhibition assays. Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) was used to quantify transport activity.

RESULTS

BUP and its major active metabolites were actively transported into the CHO or HEK293 cells overexpressing OATP1B1, OATP1B3 or OATP2B1; however, such cellular active uptake could not be inhibited at all by prototypical inhibitors of any of the OATP transporters. These compounds were not transported by OCT1, BCRP, MRP2 or P-gp either. These results suggest that the major known hepatic transporters likely play a minor role in the overall disposition and systemic clearance of BUP and its active metabolites in humans. We also demonstrated that BUP and its metabolites were not transported by OATP4A1, an uptake transporter on the apical membrane of placental syncytiotrophoblasts, suggesting that OATP4A1 is not responsible for the transfer of BUP and its metabolites from the maternal blood to the fetal compartment across the placental barrier in pregnant women.

CONCLUSION

BUP and metabolites are not substrates of the major hepatic transporters tested and thus these hepatic transporters likely do not play a role in the overall disposition of the drug. Our results also suggest that caution should be taken when using the model CHO and HEK293 cell lines to evaluate potential roles of transporters in drug disposition.

Psychiatric symptoms post intensive care unit admission

A 53-year-old woman was admitted to a tertiary intensive care unit (ICU) with acute respiratory distress syndrome secondary to severe community-acquired pneumonia that necessitated maximum supportive care with venovenous extracorporeal membrane oxygenation. Her medical history included bipolar disorder on quetiapine and sertraline, as well as a previous ICU admission, approximately 2 years prior, for non-cirrhotic hyperammonaemic encephalopathy that was complicated by prolonged post discharge anxiety and post-traumatic stress disorder-like symptoms, consistent with post-intensive-care syndrome. Here, we present a case, and explore the outcomes for a patient who had two separate admissions with life-threatening illnesses, but had distinct differences in the psychological outcomes following each illness.

Hepatic gene expression explains primary drug toxicity in bipolar disorder

In bipolar disorder (BPD), long-term psychotropic drug treatment is often necessary to prevent relapse or recurrence. Nevertheless, adverse drug effects including disturbances in hepatic metabolism are observed and still poorly understood. Here, the association between hepatic gene expression and histopathological changes of the liver was investigated. By the use of microarrays (Affymetrix U133 plus2.0), a genome-wide expression study was performed on BPD patients with psychotropic drug treatment (n = 29) compared to unaffected controls (n = 20) and validated by quantitative real-time PCR. WebGestalt was used to identify over-represented functional pathways of the Reactome database. Association analyses between histopathological changes and differentially expressed genes comprised in the over-represented functional pathways were performed using regression analyses, from which feature-expression heatmaps were drawn. The majority of identified genes were underexpressed and involved in energy supply, metabolism of lipids and proteins, and the innate immune system. Positive associations were found for genes involved in all pathways and degenerative changes. The strongest negative association was observed between genes involved in energy supply and hepatic activity, as well as inflammation. In summary, we found a possible association between gene expression involved in various biological pathways and histopathological changes of the liver in BPD. Further, we found support for the probable primary toxic effect of psychotropic drugs on hepatic injury in BPD. Even if the safety of psychotropic drugs improves, adverse effects especially on hepatic function should not be underestimated.

Aripiprazole-induced Hepatitis: A Case Report

Aripiprazole is an atypical antipsychotic that acts as a partial agonist of dopamine type 2 receptors as well as 5-HT1A receptors. It is used in the treatment of schizophrenia and in type 1 bipolar disorder for mania. Because aripiprazole is well tolerated with few side effects it is used off-label in other psychotic disorders. The prevalence of abnormal liver function tests with antipsychotic use is 32%, with clinically significant effects in 4% of cases. No cases of aripiprazole-induced liver injury have been published. We report a 28-year-old female who presented with non-affective first-episode psychosis and who was treated with aripiprazole. Initially she was medicated with 10 mg per day, with an increase to 20 mg per day on the 12th day of hospitalization. Nine days after she became icteric, with nausea and had a vomiting episode. Laboratory analysis revealed a very high level of alanine aminotransferase, and minor to moderately high levels of aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, and bilirubin. Aripiprazole was tapered and paliperidone was started with the improvement of clinical and laboratory findings.

Valproate for acute mania

BACKGROUND

Bipolar disorder is a severe and common mental disorder where patients experience recurrent symptoms of elevated or irritable mood, depression, or a combination of both. Treatment is usually with psychiatric medication, including mood stabilisers, antidepressants and antipsychotics. Valproate is an effective maintenance treatment for bipolar disorder. However, evidence assessing the efficacy of valproate in the treatment of acute mania is less robust, especially when comparing it to some of the newer antipsychotic agents. This review is an update of a previous Cochrane Review (last published 2003) on the role of valproate in acute mania.

OBJECTIVES

To assess the efficacy and tolerability of valproate for acute manic episodes in bipolar disorder compared to placebo, alternative pharmacological treatments, or a combination pharmacological treatments, as measured by the treatment of symptoms on specific rating scales for individual episodes in paediatric, adolescent and adult populations.

SEARCH METHODS

We searched Ovid MEDLINE (1950- ), Embase (1974- ), PsycINFO (1967- ) and the Cochrane Central Register of Controlled Trials (CENTRAL) to 28 September 2018. We had also conducted an earlier search of these databases in the Cochrane Common Mental Disorders Controlled Trials Register (CCMDCTR) (all years to 6 June 2016). We also searched the World Health Organization (WHO) trials portal (ICTRP) and clinicaltrials.gov in September 2018, to identify any additional unpublished or ongoing studies.

SELECTION CRITERIA

Single- and double-blind, randomised controlled trials comparing valproate with placebo, alternative antimanic treatments, or a combination of pharmacological treatments. We also considered studies where valproate was used as an adjunctive treatment in combination with another agent separately from studies where it was used in monotherapy. We included male and female patients of all ages and ethnicity with bipolar disorder.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and methodological quality assessment. For analysis, we used the odds ratio (OR) for binary efficacy outcomes and the mean difference (MD) or standardised mean difference (SMD) for continuously distributed outcomes.

MAIN RESULTS

Twenty-five trials (3252 participants) compared valproate with either placebo or alternative antimanic treatments to alleviate the symptoms of acute mania. For efficacy, our primary outcome was response rate. For tolerability, our primary outcome was the number of participants with any adverse effect. This meta-analysis included studies focusing on children, adolescents, as well as adults with a range of severity of manic symptoms. The majority of studies focused on adult men and women (aged 18 and above), were conducted in inpatient settings and completed in the US. Five studies in this review focused on children and adolescents (aged 18 and under) so that the review covers an age range from 3 - 82 years. Seven studies contained outpatient participants in some form. Nine studies included data that has been collected outside the US, namely Iran (4 studies), India (3 studies), China (1 study), or across several international countries (1 study).In adults, high-quality evidence found that valproate induces a slightly higher response compared to placebo (45% vs 29%, OR 2.05, 95% CI 1.32 to 3.20; 4 studies, 869 participants). Moderate-quality evidence found there was probably little or no difference in response rates between valproate and lithium (56% vs 62%, OR 0.80, 95% CI 0.48 to 1.35; 3 studies, 356 participants). In adults, low-quality evidence found there may be little or no difference in response rate between valproate and olanzapine (38% vs 44%, OR 0.77, 95% CI 0.48 to 1.25; 2 studies, 667 participants).In the children and adolescent population, the evidence regarding any difference in response rates between valproate and placebo was uncertain (23% vs 22%, OR 1.11, 95% CI 0.51 to 2.38; 1 study, 151 participants, very low-quality evidence). Low-quality evidence found that the response rate of participants receiving valproate may be lower compared to risperidone (23% vs 66%, OR 0.16, 95% CI 0.08 to 0.29; 1 study, 197 participants). The evidence regarding any difference in response rates between valproate and lithium was uncertain (23% vs 34%, OR 0.57, 95% CI 0.31 to 1.07; 1 study, 197 participants, very low-quality evidence).In terms of tolerability in adults, moderate-quality evidence found that there are probably more participants receiving valproate who experienced any adverse events compared to placebo (83% vs 75%, OR 1.63, 95% CI 1.13 to 2.36; 3 studies, 745 participants). Low-quality evidence found there may be little or no difference in tolerability between valproate and lithium (78% vs 86%, OR 0.61, 95% CI 0.25 to 1.50; 2 studies, 164 participants). We did not obtain primary tolerability outcome data on the olanzapine comparison.Within the children and adolescent population, the evidence regarding any difference between valproate or placebo was uncertain (67% vs 60%, OR 1.39, 95% CI 0.71 to 2.71; 1 study, 150 participants, very low-quality evidence). We did not obtain primary tolerability outcome data on the lithium or risperidone comparisons.

AUTHORS' CONCLUSIONS

There is evidence that valproate is an efficacious treatment for acute mania in adults when compared to placebo. By contrast, there is no evidence of a difference in efficacy between valproate and placebo for children and adolescents. Valproate may be less efficacious than olanzapine in adults, and may also be inferior to risperidone as a monotherapy treatment for paediatric mania. Generally, there is uncertain evidence regarding whether valproate causes more or less side effects than the other main antimanic therapies. However, evidence suggests that valproate causes less weight gain and sedation than olanzapine.

Effect of hepatic and renal impairment on the pharmacokinetics of olanzapine and samidorphan given in combination as a bilayer tablet

Background

A combination of olanzapine and samidorphan (OLZ/SAM) is in development to provide the established antipsychotic efficacy of olanzapine while mitigating olanzapine-induced weight gain.

Methods

Two multicenter, open-label, parallel-cohort studies were performed to evaluate the effect of moderate hepatic impairment (Child-Pugh score 7–9 [class B]; study 1) and severe renal impairment (estimated glomerular filtration rate: 15–29 mL/min/1.73 m²; study 2) on the pharmacokinetics, safety, and tolerability of a single dose of OLZ/SAM 5/10 mg.

Results

There was a 1.67-fold increase in area under the plasma concentration-time curve from time 0 to infinity (AUC_0-∞) and a 2.17-fold increase in maximum plasma concentration (C_max) of olanzapine, and a 1.52-fold increase in AUC_0-∞ and a 1.63-fold increase in C_max of samidorphan, in subjects with moderate hepatic impairment compared with healthy control subjects. Compared with healthy control subjects, subjects with severe renal impairment had a 33% and 56% reduction in clearance, a 1.51- and 2.31-fold increase in AUC_0-∞, and a 1.32- and 1.37-fold increase in C_max of olanzapine and samidorphan, respectively.

Conclusion

OLZ/SAM 5/10 mg was generally well tolerated under the conditions of the studies, with a safety profile consistent with that observed in other clinical studies of OLZ/SAM.

Mental health and cognitive function responses to quetiapine in patients with methamphetamine abuse under methadone maintenance treatment

BACKGROUND

Patients with methamphetamine (MA) abuse under methadone maintenance treatment (MMT) are susceptible to several complications including cognitive disturbance and mental health disorder. This trial was designed to determine the impacts of quetiapine administration on cognitive function and mental health scale in patients with MA abuse under MMT.

METHODS

This study was carried out in 60 MA abusers under MMT. Patients were randomly allocated to receive either 100 mg quetiapine (n = 30) or control (n = 30) daily for 8 weeks. Cognitive function and mental health scale were taken at baseline and post-treatment to evaluate relevant variables.

RESULTS

Quetiapine significantly decreased depression (b -3.94; 95% CI, -7.73, -0.16; P = 0.04) and sleep disorder (b -2.18; 95% CI, -2.89, -1.47; P < 0.001). Also, quetiapine administration resulted in a significant reduction in Iowa Gambling Task (b -2.70; 95% CI, -4.69, -0.71; P = 0.009), and significant increases in Verbal Fluency Test (b 3.04; 95% CI, 1.24, 4.85; P = 0.001), Reverse Digit Span (b 2.80; 95% CI, 2.13, 3.47; P = 0.001) compared with the placebo.

CONCLUSION

Overall, taking 100 mg quetiapine daily for 8 weeks by patients MA abuse in MMT had favorable effects on some of cognitive functions and mental health parameters.

Positive effects of systemic sodium benzoate and olanzapine treatment on activities of daily life, spatial learning and working memory in ketamine-induced rat model of schizophrenia

BACKGROUND

Sodium Benzoate (SB) significantly improved positive, negative, and cognitive symptoms as add on treatment in schizophrenia. Olanzapine (Ola), the most effective atypical antipsychotic drug, has been linked to hepatic steatosis, acute kidney injury, reproductive side effects and poor effect on negative symptoms in some patients.

GOALS

is to compare the efficacy and check the safety of long-term monotherapy with SB 0.01 mg/Kg versus Ola on male cognitive, memory, hepatic, renal and testicular functions in rat model of schizophrenia.

METHODS

48 young adult male rats were divided into 6 groups; C: control; O: received Ola; SB: received SB; K: received single IP ketamine (Ket) injection; K+O: received Ola and Ket and K+SB: received SB and Ket. Ola and SB given orally for 3 or 10 weeks for behavioral or serological studies respectively. We measured activities of daily life (ADL), spatial learning and memory in radial arm water maze (RAWM), serum parameters of hepatic, renal and testicular functions.

RESULTS

Both Ola and SB significantly improved hoarding and burrowing, caused significant decrease in time to reach target (TRT), working memory errors (WME) in K+O and K+SB groups compared to K group. Ola caused significant increase in ALT, AST and creatinine and decrease in serum LH, testosterone compared to controls. SB caused significant rise in serum LH, ALT, AST and decrease in protein and albumin compared to both C and O groups.

CONCLUSION

Both Ola and SB improved ADL, cognitive and memory functions. Although SB saved testicular and renal functions, it worsened liver function compared to Ola.

Analysis of psychotropic drug-related deaths in south Osaka

Objective

The aim of this study was to investigate the occurrence of deaths due to psychotropic drugs in south Osaka during a 10-year period and discuss societal factors from a medical viewpoint.

Methods

Psychotropic drug-related deaths were retrospectively investigated based on the forensic postmortem data of 1,746 decedents in 2005-2014, and we excluded cases in which stimulant drugs were detected. Of these, 133 cases (7.6%) were found to be psychotropic drug-related deaths and were analyzed.

Results

Psychotropic drug-related deaths occurred in 78 males (59%; age range, 14-95 years) and 55 females (41%; 20-84 years). The direct cause of death was acute drug intoxication in many cases, and of these, acute combined drug intoxication due to the use of multiple drugs accounted for 76% of the deaths. Most of these victims were found to have gastrointestinal and cardiovascular diseases. Cases of psychotropic drug-related deaths had especially poor medical conditions. In addition, tests were positive for blood alcohol in 23% of the cases.

Conclusion

The descriptive results revealed several factors that may be related to psychotropic drug-related deaths. To prevent drug abuse, several factors were deemed to be important, including improvements in the medical state of an individual, the avoidance of social isolation, and from a medical standpoint, the management of prescription drugs by medical personnel.

Flupirtine drug-induced liver injury in a patient developing acute liver failure

A patient is admitted with complaints of recent onset nausea, discomfort, jaundice and blood tests that reveal severe hepatitis. At the time, she had been taking medication with Hypericum perforatum (St John's wort) for 6 months, and 6 weeks before this event, she took flupirtine maleate. A few days after being admitted, she developed encephalopathy progressing to acute liver failure (ALF) requiring unsuccessful liver transplantation. The patient was ultimately diagnosed with drug-induced liver injury (DILI). In this context, while H. perforatum could interfere with other medication or trigger DILI itself, flupirtine appears to have triggered the DILI, given its liver toxicity capacity. DILI is one of the major ALF causes and can jeopardise patient's life. Accordingly, all efforts to reduce medication potentially hazardous to the liver are recommended.