Drugs, Metabolites, and Lung Accumulating Small Lysosomotropic Molecules: Multiple Targeting Impedes SARS-CoV-2 Infection and Progress to COVID-19.

Lysosomotropism is a biological characteristic of small molecules, independently present of their intrinsic pharmacological effects. Lysosomotropic compounds, in general, affect various targets, such as lipid second messengers originating from lysosomal enzymes promoting endothelial stress response in systemic inflammation; inflammatory messengers, such as IL-6; and cathepsin L-dependent viral entry into host cells. This heterogeneous group of drugs and active metabolites comprise various promising candidates with more favorable drug profiles than initially considered (hydroxy) chloroquine in prophylaxis and treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections/Coronavirus disease 2019 (COVID-19) and cytokine release syndrome (CRS) triggered by bacterial or viral infections. In this hypothesis, we discuss the possible relationships among lysosomotropism, enrichment in lysosomes of pulmonary tissue, SARS-CoV-2 infection, and transition to COVID-19. Moreover, we deduce further suitable approved drugs and active metabolites based with a more favorable drug profile on rational eligibility criteria, including readily available over-the-counter (OTC) drugs. Benefits to patients already receiving lysosomotropic drugs for other pre-existing conditions underline their vital clinical relevance in the current SARS-CoV2/COVID-19 pandemic.

Inhibition of the replication of SARS-CoV-2 in human cells by the FDA-approved drug chlorpromazine.

INTRODUCTION: Urgent action is needed to fight the ongoing coronavirus disease 2019 (COVID-19) pandemic by reducing the number of infected cases, contagiousness and severity. Chlorpromazine (CPZ), an antipsychotic from the phenothiazine group, is known to inhibit clathrin-mediated endocytosis and has antiviral activity against severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1) and Middle East respiratory syndrome coronavirus. The aim of this in-vitro study was to test CPZ against SARS-CoV-2 in monkey and human cells. MATERIALS AND METHODS: Monkey VeroE6 cells and human alveolar basal epithelial A549-ACE2 cells were infected with SARS-CoV-2 in the presence of various concentrations of CPZ. Supernatants were harvested at day 2 and analysed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) for the presence of SARS-CoV-2 RNA. Cell viability was assessed in non-infected cells. RESULTS: CPZ was found to have antiviral activity against SARS-CoV-2 in monkey VeroE6 cells, with a half maximal inhibitory concentration (IC50) of 8.2 µM, half maximal cytotoxic concentration (CC50) of 13.5 µM, and selectivity index (SI) of 1.65. In human A549-ACE2 cells, CPZ was also found to have anti-SARS-CoV-2 activity, with IC50 of 11.3 µM, CC50 of 23.1 µM and SI of 2.04. DISCUSSION: Although the measured SI values are low, the IC50 values measured in vitro may translate to CPZ dosages used in routine clinical practice because of the high biodistribution of CPZ in lungs and saliva. Also, the distribution of CPZ in brain could be of interest for treating or preventing neurological and psychiatric forms of COVID-19. CONCLUSIONS: These preclinical findings support clinical investigation of the repurposing of CPZ, a drug with mild side effects, in the treatment of patients with COVID-19.

[Repurposing of chlorpromazine in COVID-19 treatment: the reCoVery study]. / Repositionnement de la chlorpromazine dans le traitement du COVID-19 : étude reCoVery.

OBJECTIVES: The ongoing COVID-19 pandemic comprises a total of more than 2,350,000 cases and 160,000 deaths. The interest in anti-coronavirus drug development has been limited so far and effective methods to prevent or treat coronavirus infections in humans are still lacking. Urgent action is needed to fight this fatal coronavirus infection by reducing the number of infected people along with the infection contagiousness and severity. Since the beginning of the COVID-19 outbreak several weeks ago, we observe in GHU PARIS Psychiatrie & Neurosciences (Sainte-Anne hospital, Paris, France) a lower prevalence of symptomatic and severe forms of COVID-19 infections in psychiatric patients (∼4%) compared to health care professionals (∼14%). Similar observations have been noted in other psychiatric units in France and abroad. Our hypothesis is that psychiatric patients could be protected from severe forms of COVID-19 by their psychotropic treatments. Chlorpromazine (CPZ) is a phenothiazine derivative widely used in clinical routine in the treatment of acute and chronic psychoses. This first antipsychotic medication has been discovered in 1952 by Jean Delay and Pierre Deniker at Sainte-Anne hospital. In addition, to its antipsychotic effects, several in vitro studies have also demonstrated a CPZ antiviral activity via the inhibition of clathrin-mediated endocytosis. Recently, independent studies revealed that CPZ is an anti-MERS-CoV and an anti-SARS-CoV-1 drug. In comparison to other antiviral drugs, the main advantages of CPZ lie in its biodistribution: (i) preclinical and clinical studies have reported a high CPZ concentration in the lungs (20-200 times higher than in plasma), which is critical because of the respiratory tropism of SARS-CoV-2; (ii) CPZ is highly concentrated in saliva (30-100 times higher than in plasma) and could therefore reduce the contagiousness of COVID-19; (iii) CPZ can cross the blood-brain barrier and could therefore prevent the neurological forms of COVID-19. METHODS: Our hypothesis is that CPZ could decrease the unfavorable evolution of COVID-19 infection in oxygen-requiring patients without the need for intensive care, but also reduce the contagiousness of SARS-CoV-2. At this end, we designed a pilot, phase III, multicenter, single blind, randomized controlled clinical trial. Efficacy of CPZ will be assessed according to clinical, biological and radiological criteria. The main objective is to demonstrate a shorter time to response (TTR) to treatment in the CPZ+standard-of-care (CPZ+SOC) group, compared to the SOC group. Response to treatment is defined by a reduction of at least one level of severity on the WHO-Ordinal Scale for Clinical Improvement (WHO-OSCI). The secondary objectives are to demonstrate in the CPZ+SOC group, compared to the SOC group: (A) superior clinical improvement; (B) a greater decrease in the biological markers of viral attack by SARS-CoV-2 (PCR, viral load); (C) a greater decrease in inflammatory markers (e.g. CRP and lymphopenia); (D) a greater decrease in parenchymal involvement (chest CT) on the seventh day post-randomization; (E) to define the optimal dosage of CPZ and its tolerance; (F) to evaluate the biological parameters of response to treatment, in particular the involvement of inflammatory cytokines. Patient recruitment along with the main and secondary objectives are in line with WHO 2020 COVID-19 guidelines. CONCLUSION: This repositioning of CPZ as an anti-SARS-CoV-2 drug offers an alternative and rapid strategy to alleviate the virus propagation and the infection severity and lethality. This CPZ repositioning strategy also avoids numerous developmental and experimental steps and can save precious time to rapidly establish an anti-COVID-19 therapy with well-known, limited and easy to manage side effects. Indeed, CPZ is an FDA-approved drug with an excellent tolerance profile, prescribed for around 70 years in psychiatry but also in clinical routine in nausea and vomiting of pregnancy, in advanced cancer and also to treat headaches in various neurological conditions. The broad spectrum of CPZ treatment - including antipsychotic, anxiolytic, antiemetic, antiviral, immunomodulatory effects along with inhibition of clathrin-mediated endocytosis and modulation of blood-brain barrier - is in line with the historical French commercial name for CPZ, i.e. LARGACTIL, chosen as a reference to its "LARGe ACTion" properties. The discovery of those CPZ properties, as for many other molecules in psychiatry, is both the result of serendipity and careful clinical observations. Using this approach, the field of mental illness could provide innovative therapeutic approaches to fight SARS-CoV-2.

Anticholinergic Load and Nutritional Status in Older Individuals.

OBJECTIVES: The association between anticholinergic load-based Anticholinergic Risk Scale scores and nutritional status is unclear in Japanese patients. The aim of this study was to establish whether anticholinergic load affects the nutritional status of geriatric patients in convalescent stages. DESIGN: Retrospective longitudinal cohort study. SETTING: Convalescent rehabilitation wards. PARTICIPANTS: Of the 1490 patients aged ≥65 years who were discharged from convalescent rehabilitation wards between July 2010 and October 2018, 908 patients met the eligibility criteria. They were categorized according to the presence or absence of increased anticholinergic load from admission to discharge. MEASUREMENTS: Demographic data, laboratory data, the Functional Independence Measure were analyzed between the groups. The primary outcome was Geriatric Nutritional Risk Index (GNRI) at discharge. Multiple linear regression analysis was performed to analyze the relationship between anticholinergic load and GNRI at discharge. RESULTS: Multiple linear regression analysis after adjusting for confounding factors revealed that anticholinergic load was independently and negatively correlated with GNRI at discharge. Particularly, the use of chlorpromazine, hydroxyzine, haloperidol, metoclopramide, risperidone, etc. increased significantly from admission to discharge. CONCLUSION: Increased anticholinergic load during hospitalization may be a predictor of nutritional status in geriatric patients.

Investigation of metabolite-protein interactions by transient absorption spectroscopy and in silico methods.

Transient absorption spectroscopy in combination with in silico methods has been employed to study the interactions between human serum albumin (HSA) and the anti-psychotic agent chlorpromazine (CPZ) as well as its two demethylated metabolites (MCPZ and DCPZ). Thus, solutions containing CPZ, MCPZ or DCPZ and HSA (molar ligand:protein ratios between 1:0 and 1:3) were submitted to laser flash photolysis and the ΔAmax value at λ = 470 nm, corresponding to the triplet excited state, was monitored. In all cases, the protein-bound ligand exhibited higher ΔAmax values measured after the laser pulse and were also considerably longer-lived than the non-complexed forms. This is in agreement with an enhanced hydrophilicity of the metabolites, due to the replacement of methyl groups with H that led to a lower extent of protein binding. For the three compounds, laser flash photolysis displacement experiments using warfarin or ibuprofen indicated Sudlow site I as the main binding site. Docking and molecular dynamics simulation studies revealed that the binding mode of the two demethylated ligands with HSA would be remarkable different from CPZ, specially for DCPZ, which appears to come from the different ability of their terminal ammonium groups to stablish hydrogen bonding interactions with the negatively charged residues within the protein pocket (Glu153, Glu292) as well as to allocate the methyl groups in an apolar environment. DCPZ would be rotated 180° in relation to CPZ locating the aromatic ring away from the Sudlow site I of HSA.

A sensitive capillary LC-UV method for the simultaneous analysis of olanzapine, chlorpromazine and their FMO-mediated N-oxidation products in brain microdialysates.

A specific and sensitive capillary liquid chromatography-ultraviolet detection (cap-LC-UV) method in combination with a micro-extraction by packed sorbent (MEPS) sample clean-up procedure has been developed and validated for the simultaneous analysis of chlorpromazine, olanzapine and their flavin-containing monooxygenase (FMO) mediated N-oxides in rat brain microdialysates. Chromatographic separation was obtained on an Acclaim Pepmap RP C18 column with an ID of 300µm. An injection volume of 20µL was used to inject the largely aqueous samples and was shown to have no influence on the obtained peak shape of the compounds of interest. Optimal conditions for MEPS extraction were obtained on a mixed-mode M1 (80% C8, 20% SCX) cartridge after diluting microdialysate samples with phosphate buffer pH 2.5 (1:3 v/v). The method was validated and lower limits of quantification (LLOQ) were determined at 0.5nM for all compounds. Linearity was demonstrated between the LLOQ and 1µM for all compounds (R2>0.995). MEPS recoveries were between 92% and 98%, with intra- and interday variabilities below 15%. The applicability of the developed method was successfully demonstrated by analysing rat brain microdialysates. The capillary LC-UV method in combination with MEPS sample treatment provides a simple, sensitive method to quantify all compounds of interest in 45min and can be applied for routine therapeutic monitoring and pharmacokinetic studies of olanzapine, chlorpromazine and their respective N-oxides.

Tales from the war on error: the art and science of curating QSAR data.

Curating the data underlying quantitative structure-activity relationship models is a never-ending struggle. Some curation can now be automated but much cannot, especially where data as complex as those pertaining to molecular absorption, distribution, metabolism, excretion, and toxicity are concerned (vide infra). The authors discuss some particularly challenging problem areas in terms of specific examples involving experimental context, incompleteness of data, confusion of units, problematic nomenclature, tautomerism, and misapplication of automated structure recognition tools.

The in vitro biokinetics of chlorpromazine and diazepam in aggregating rat brain cell cultures after repeated exposure.

Neurotoxic effects of compounds can be tested in vitro using cell systems. One example is aggregating rat brain cell cultures. For the extrapolation of in vitro data to the in vivo situation, it is important to take the biokinetics of the test compound into account. In addition, the exposure in vivo is often for a longer period of time; therefore, it is crucial to incorporate this into in vitro assays as well. In this study, aggregating rat brain cell cultures were exposed to chlorpromazine (CPZ) and diazepam (DZP) for 12-days with repeated exposure. Samples were taken from the stocks, test media, cell culture media and cells at specific time points on the first and last exposure day. These samples were analysed by HPLC-UV. The amount of CPZ in the medium decreased over time, whereas the amount in the cells showed an increase. Accumulation of CPZ in the cells was seen over the 12-day repeated exposure. The amount of DZP in the medium remained stable over time and only up to 2% of DZP added was found in the cells. Different biokinetic behaviour was found for CPZ and DZP. Possible explanations are differences in uptake into the cells or efflux out of the cells. The decrease of CPZ in the medium versus the stable amount of DZP results in differences in exposure concentrations over time, which should be taken into account when interpreting in vitro effect data.

Biokinetics of chlorpromazine in primary rat and human hepatocytes and human HepaRG cells after repeated exposure.

Since drug induced liver injury is difficult to predict in animal models, more representative tests are needed to better evaluate these effects in humans. Existing in vitro systems hold great potential to detect hepatotoxicity of pharmaceuticals. In this study, the in vitro biokinetics of the model hepatotoxicant chlorpromazine (CPZ) were evaluated in three different liver cell systems after repeated exposure in order to incorporate repeated-dose testing into an in vitro assay. Primary rat and human hepatocytes, cultured in sandwich configuration and the human HepaRG cell line were treated daily with CPZ for 14 days. Samples were taken from medium, cells and well plastic at specific time points after the first and last exposure. The samples were analysed by HPLC-UV to determine the amount of CPZ in these samples. Based on cytotoxicity assays, the three models were tested at 1-2 µM CPZ, while the primary rat hepatocytes and the HepaRG cell line were in addition exposed to a higher concentration of 15-20 µM. Overall, the mass balance of CPZ decreased in the course of 24 h, indicating the metabolism of the compound within the cells. The largest decrease in parent compound was seen in the primary cultures; in the HepaRG cell cultures the mass balance only decreased to 50%. CPZ accumulated in the cells during the 14-day repeated exposure. Possible explanations for the accumulation of CPZ are a decrease in metabolism over time, inhibition of efflux transporters or binding to phospholipids. The biokinetics of CPZ differed between the three liver cell models and were influenced by specific cell properties as well as culture conditions. These results support the conclusion that in vitro biokinetics data are necessary to better interpret chemical-induced cytotoxicity data.

Comparison of the anti-dopamine D2 and anti-serotonin 5-HT(2A) activities of chlorpromazine, bromperidol, haloperidol and second-generation antipsychotics parent compounds and metabolites thereof.

Second-generation antipsychotics, which have become the standard drug therapies for schizophrenia, are known to have a serotonin 5-HT(2A) receptor blocking effect in addition to a dopamine D2 receptor blocking effect. However, although chlorpromazine (CPZ) has a 5-HT(2A) receptor blocking effect and has the profile of a second-generation antipsychotic in vitro, it loses this pharmacological profile in vivo. In order to elucidate the differences between the in vivo and in vitro pharmacological characteristics of CPZ, we used a radioreceptor assay to measure the anti-D2 activity and the anti-5-HT(2A) activity of CPZ and five major metabolites of CPZ, and compared the results to the anti-D2 activity and anti-5-HT(2A) activity of risperidone, zotepine, perospirone, the major metabolites of each of these drugs, and olanzapine, bromperidol, and haloperidol. The subjects were 182 patients who had received diagnoses of schizophrenia based on the DSM-IV criteria. The results revealed that CPZ exhibited little anti-5-HT(2A) activity, regardless of the anti-D2 activity level, and that none of the metabolites possessed anti-5-HT(2A) activity. However, both the parent compounds and the metabolites of each of the second-generation antipsychotics possessed both anti-D2 activity and anti-5-HT(2A) activity. This clarified that, unlike second-generation antipsychotics, the reason CPZ loses its second-generation antipsychotic profiles in vivo is because it does not have any metabolites that possess anti-5-HT(2A) activity.

Chlorpromazine bioavailability from a topical gel formulation in volunteers.

BACKGROUND: Symptom management medications are often compounded into topical gel formulations providing an alternative route of administration for hospice and palliative care patients. Though commonly used, transdermal absorption and bioavailability studies of these gel products are lacking. Chlorpromazine was studied because it is FDA approved for treatment of nausea and vomiting and is used off-label for treatment of agitation and delirium. OBJECTIVE: The objective of this study is to determine the transdermal absorption of chlorpromazine PLO gel in healthy adults. METHODS: Twenty-five milligrams of chlorpromazine in PLO gel was applied to 10 subjects' wrists and 100 mg was applied to 1 subject's wrist. Blood draws were completed preapplication and 1, 2, and 4 hours postapplication. This single-center unblinded study recruited healthy adults between 18 and 70 years of age. Participants were not pregnant, did not have an allergy to any component of the study medication, and were not taking a phenothiazine medication. RESULTS: Chlorpromazine was undetected in any of the 11 subjects' blood samples. LIMITATIONS: There is an assumption of equivalent medication absorption in healthy patients and palliative care or hospice patients. CONCLUSION: Rapid relief of symptoms at end of life is essential. Chlorpromazine in PLO gel may not be an effective treatment option since blood levels were undetectable at 1, 2, and 4 hours after topical application.

Las bodas de diamante de la clorpromazina / No disponible

No disponible

Does the medication pattern reflect the CYP2D6 genotype in patients with diagnoses within the schizophrenic spectrum?

BACKGROUND: Cytochrome P450 2D6 enzyme (CYP2D6) is an important metabolic pathway for many antipsychotics. Its genetic polymorphism causes pharmacokinetic variability that might lead to adverse drug reactions or treatment failure unless countered by appropriate dose adjustments or shift to CYP2D6-independent antipsychotics. PURPOSE: To investigate the clinical impact of CYP2D6 genotype in patients with a diagnosis within the schizophrenic spectrum using medication pattern as proxy for therapeutic and side effect. METHODS: The study was conducted in patients genotyped during an inpatient stay (N = 576). Continuous antipsychotic, adjuvant, and anticholinergic drug regimens were registered retrospectively in a cross-sectional manner before genotyping. Antipsychotics were divided into CYP2D6 dependent and independent, and dose equivalents were calculated as chlorpromazine equivalents (CPZEq). RESULTS: Poor metabolizers and ultrarapid metabolizers were treated with significantly higher median CPZEq doses (625.8; inter quartile range [IQR], 460.4-926.7; and 550; IQR, 199.8-1049) than extensive metabolizers (EMs) and intermediate metabolizers (IMs) (384; IQR, 150-698; and 446; IQR, 150-800) (P = 0.018). Logistic regression showed no association between anticholinergic treatment and CYP2D6 genotype or concomitant treatment with CYP2D6 inhibitors (P = 0.79 and P = 0.46, respectively). CONCLUSIONS: Our results indicate that CYP2D6 genotype has no sufficient clinical impact that poor metabolizers and ultrarapid metabolizers are easily clinically identified with.

Chlorpromazine quantification in human plasma by UPLC-electrospray ionization tandem mass spectrometry. Application to a comparative pharmacokinetic study.

In the present study a method to quantify chlorpromazine in human plasma using cyclobenzaprine as the internal standard (IS) is described. The analyte and the IS were extracted from human plasma by a liquid-liquid extraction with diethyl ether/dichloromethane (70/30, v/v) and analyzed by an ultra performance liquid chromatography (UPLC) coupled to an electrospray tandem triple quadrupole mass spectrometer in positive mode (UPLC-ES(+)-MS/MS). Chromatography was performed isocratically on an Aquity UPLC BEH C18 1.7 µm (50 mm × 2.1 mm i.d.) operating at 40°C. The mobile phase was a mixture of 65% water+1% formic acid and 35% of acetonitrile at a flow-rate of 0.5 mL/min. The lowest concentration quantified was 0.5 ng/mL and a linear calibration curve over the range 0.5-200 ng/mL was obtained, showing intra-assay precisions from 2.4 to 5.8%, and inter-assay precisions from 3.6 to 9.9%. The intra-assay accuracies ranged from 96.9 to 102.5%, while the inter-assay accuracies ranged from 94.1 to 100.3%. This analytical method was applied in a relative bioavailability study in order to compare a test chlorpromazine 100 mg simple dose formulation versus a reference in 57 volunteers of both sexes. The study was conducted in an open randomized two-period crossover design and with a fourteen days washout period. Plasma samples were obtained over a 144-h interval. Since the 90% CI for both C(max), AUC(last) and AUC(0-inf) were within the 80-125% interval proposed by the Food and Drug Administration and ANVISA, it was concluded that chlorpromazine 100 mg/dose was bioequivalent to the reference formulation, according to both the rate and extent of absorption.

In vivo 5-HT(6) receptor occupancy by antipsychotic drugs in the rat brain.

The 5-HT(6) receptor subtype is predominantly expressed in the central nervous system, and preclinical evidence suggests that it plays a critical role in the regulation of molecular pathways underlying cognitive function. Patients with schizophrenia show cognitive impairment as a fundamental symptom, and it is proposed that the procognitive properties of some antipsychotics such as olanzapine and clozapine would be, in part, due to the central blockade of 5-HT(6) receptors. In this study, we characterized the brain 5-HT(6) receptor occupancy of olanzapine, clozapine and chlorpromazine in relation to their pharmacokinetic profiles using in vivo [(3)H]GSK215083 binding assay in rat brain. Oral administration of olanzapine (3mg/kg), clozapine (30mg/kg) and chlorpromazine (30mg/kg) produced significant 5-HT(6) receptor occupancy in the brain, inhibiting radioligand binding by 88, 97 and 81%, respectively. The blood concentrations required to achieve significant occupancy were clinically achievable (9.6, 26.9 and 98.6nM for olanzapine, clozapine and chlorpromazine, respectively). This data provides preclinical evidence to support the hypothesis that brain 5-HT(6) antagonism contributes to the procognitive properties of antipsychotic drugs such as olanzapine and clozapine.

Past and present progress in the pharmacologic treatment of schizophrenia.

Despite treatment advances over the past decades, schizophrenia remains one of the most severe psychiatric disorders that is associated with a chronic relapsing course and marked functional impairment in a substantial proportion of patients. In this article, a historical overview of the pharmacologic advances in the treatment of schizophrenia over the past 50 years is presented. This is followed by a review of the current developments in optimizing the treatment and outcomes in patients with schizophrenia. Methodological challenges, potential solutions, and areas of particular need for further research are highlighted. Although treatment goals of response, remission, and recovery have been defined more uniformly, a good "effectiveness" measure mapping onto functional outcomes is still lacking. Moreover, the field must advance in transferring measurement-based approaches from research to clinical practice. There is an ongoing debate regarding whether and which first- or second-generation antipsychotics should be used. However, especially when considering individual adverse effect profiles, the differentiation into first- and second-generation antipsychotics as unified classes cannot be upheld, and a more differentiated view and treatment selection are required. The desired, individualized treatment approach needs to consider current symptoms, comorbid conditions, past therapeutic response, and adverse effects, as well as patient choice and expectations. Acute and long-term goals and effects of medication treatment should be balanced. To date, clozapine is the only evidence-based treatment for refractory patients, and the role of antipsychotic polypharmacy and other augmentation strategies remains unclear, at best. To discover novel treatments with enhanced/broader efficacy and improved tolerability, and to enable personalized treatment, the mechanisms underlying illness development and progression, symptomatic improvement, and side effect development need to be elucidated.

Accumulation and metabolism of drugs and CYP probe substrates in zebrafish larvae.

This study examined the accumulation and metabolism of a number of drugs and commonly used probes for human cytochrome P450s (CYPs) in zebrafish larvae under conditions relevant to pharmacological and toxicological assays. Studies with cisapride, chlorpromazine, verapamil, testosterone, and dextromethorphan showed that the zebrafish larvae catalyze a range of phase 1 (oxidation, N-demethylation, O-de-ethylation, and N-dealkylation) and phase 2 (sulfation and glucuronidation) reactions. Both similarities and differences in the metabolic pathways were observed in zebrafish larvae when compared to mammals. Metabolism of phenacetin to paracetamol and dextromethorphan to dextrorphan (metabolic reactions catalyzed by CYP 1A2 and 2D6 in humans respectively) were observed in the zebrafish larvae. In addition the zebrafish larvae 7 days post fertilization (7 d.p.f.) hydroxylated diclofenac, bupropion, tacrine, and testosterone. Although metabolites of several compounds were detected in zebrafish larvae, in the instances where the metabolite amounts were quantified, the amount of any specific metabolite formed was low, accounting for only a small percentage of the amount of parent compound added. Furthermore, when the concentrations of metabolite present in the zebrafish larvae were compared with the measured level of parent compound, the metabolite concentrations were always much lower than that of parent compound. Overall, for the compounds used in the current study it is unlikely that the quantified metabolites would significantly contribute to the outcome of safety pharmacology or toxicology studies conducted in zebrafish larvae under the paradigms typically used for such investigations.

Hydroxypropylmethylcellulose films for prolonged delivery of the antipsychotic drug chlorpromazine.

OBJECTIVES: The aim of this study was to develop transdermal films based on hydroxypropylmethylcellulose with the purpose of improving transdermal permeation of chlorpromazine hydrochloride, an antipsychotic drug used to alleviate the symptoms and signs of psychosis. METHODS: Hydroxypropylmethylcellulose films were prepared and evaluated for their drug content, film thickness, residual water content and bioadhesive properties. In-vitro permeation experiments were performed in the absence and in the presence of permeation enhancers (oleic acid, polysorbate 80, or both) with the purpose of improving drug availability. Other formulative parameters, such as drug and plasticizer concentration and hydroxypropylmethylcellulose type, were investigated. KEY FINDINGS: Both oleic acid and polysorbate 80 had significant effect on drug permeation with respect to the control formulation. In particular films containing a mixture of oleic acid and polysorbate 80 provided the best enhancement activity for chlorpromazine. Moreover, a decrease in propylene glycol or chlorpromazine content or an increase of hydroxypropylmethylcellulose viscosity provided lower cumulative amounts of drug permeated. CONCLUSIONS: The results obtained confirm that chlorpromazine permeation can be easily modulated by varying the composition of hydroxypropylmethylcellulose-based films. These formulations could serve as candidates for transdermal delivery of antipsychotic drugs.